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authorJohn Högberg <[email protected]>2018-09-28 14:08:23 +0200
committerGitHub <[email protected]>2018-09-28 14:08:23 +0200
commit7d941c529dc9db016af30cdace2df089d1648dbf (patch)
treece04f9922931e927ca22d75a2cd0fd4d0d0328eb
parent08ef38b2c9f84ed118e693bff38efa69fc2c7eb8 (diff)
parentafa36d2081927c46a4c3ddceb40276fc7756bb51 (diff)
downloadotp-7d941c529dc9db016af30cdace2df089d1648dbf.tar.gz
otp-7d941c529dc9db016af30cdace2df089d1648dbf.tar.bz2
otp-7d941c529dc9db016af30cdace2df089d1648dbf.zip
Merge pull request #1958 from jhogberg/john/compiler/ssa-bsm-opt
Rewrite BSM optimizations in the new SSA-based intermediate format
-rw-r--r--erts/emulator/beam/beam_load.c1
-rw-r--r--erts/emulator/beam/bs_instrs.tab309
-rw-r--r--erts/emulator/beam/erl_bits.c36
-rw-r--r--erts/emulator/beam/erl_bits.h13
-rw-r--r--erts/emulator/beam/ops.tab104
-rw-r--r--lib/compiler/src/Makefile2
-rw-r--r--lib/compiler/src/beam_bsm.erl719
-rw-r--r--lib/compiler/src/beam_disasm.erl10
-rw-r--r--lib/compiler/src/beam_jump.erl2
-rw-r--r--lib/compiler/src/beam_kernel_to_ssa.erl9
-rw-r--r--lib/compiler/src/beam_ssa.erl89
-rw-r--r--lib/compiler/src/beam_ssa_bsm.erl1027
-rw-r--r--lib/compiler/src/beam_ssa_codegen.erl49
-rw-r--r--lib/compiler/src/beam_ssa_opt.erl117
-rw-r--r--lib/compiler/src/beam_ssa_pre_codegen.erl293
-rw-r--r--lib/compiler/src/beam_ssa_type.erl2
-rw-r--r--lib/compiler/src/beam_utils.erl5
-rw-r--r--lib/compiler/src/beam_validator.erl193
-rw-r--r--lib/compiler/src/compile.erl15
-rw-r--r--lib/compiler/src/compiler.app.src2
-rwxr-xr-xlib/compiler/src/genop.tab18
-rw-r--r--lib/compiler/src/sys_core_bsm.erl250
-rw-r--r--lib/compiler/src/v3_kernel.erl37
-rw-r--r--lib/compiler/test/Makefile15
-rw-r--r--lib/compiler/test/beam_validator_SUITE_data/bad_bin_match.S2
-rw-r--r--lib/compiler/test/beam_validator_SUITE_data/receive_stacked.S6
-rw-r--r--lib/compiler/test/bs_match_SUITE.erl99
-rw-r--r--lib/compiler/test/compile_SUITE.erl5
-rw-r--r--lib/compiler/test/misc_SUITE.erl11
-rw-r--r--lib/compiler/test/test_lib.erl9
-rw-r--r--lib/compiler/test/warnings_SUITE.erl51
-rw-r--r--lib/hipe/doc/src/hipe_app.xml7
-rw-r--r--lib/hipe/test/Makefile1
-rw-r--r--lib/hipe/test/basic_SUITE_data/basic_inline_function.erl73
-rw-r--r--system/doc/efficiency_guide/binaryhandling.xml8
35 files changed, 2178 insertions, 1411 deletions
diff --git a/erts/emulator/beam/beam_load.c b/erts/emulator/beam/beam_load.c
index 50cbb37f3e..c28a5c57e6 100644
--- a/erts/emulator/beam/beam_load.c
+++ b/erts/emulator/beam/beam_load.c
@@ -2868,6 +2868,7 @@ load_code(LoaderState* stp)
break;
case op_bs_put_string_WW:
case op_i_bs_match_string_xfWW:
+ case op_i_bs_match_string_yfWW:
new_string_patch(stp, ci-1);
break;
diff --git a/erts/emulator/beam/bs_instrs.tab b/erts/emulator/beam/bs_instrs.tab
index 61eb02a7a2..2dde70c2e1 100644
--- a/erts/emulator/beam/bs_instrs.tab
+++ b/erts/emulator/beam/bs_instrs.tab
@@ -102,6 +102,7 @@ i_bs_get_binary_all2(Fail, Ms, Live, Unit, Dst) {
LIGHT_SWAPIN;
HEAP_SPACE_VERIFIED(0);
ASSERT(is_value(_result));
+ $REFRESH_GEN_DEST();
$Dst = _result;
} else {
HEAP_SPACE_VERIFIED(0);
@@ -123,6 +124,7 @@ i_bs_get_binary2(Fail, Ms, Live, Sz, Flags, Dst) {
if (is_non_value(_result)) {
$FAIL($Fail);
} else {
+ $REFRESH_GEN_DEST();
$Dst = _result;
}
}
@@ -139,6 +141,7 @@ i_bs_get_binary_imm2(Fail, Ms, Live, Sz, Flags, Dst) {
if (is_non_value(_result)) {
$FAIL($Fail);
} else {
+ $REFRESH_GEN_DEST();
$Dst = _result;
}
}
@@ -161,6 +164,7 @@ i_bs_get_float2(Fail, Ms, Live, Sz, Flags, Dst) {
if (is_non_value(_result)) {
$FAIL($Fail);
} else {
+ $REFRESH_GEN_DEST();
$Dst = _result;
}
}
@@ -724,26 +728,34 @@ bs_start_match.execute(Fail, Live, Slots, Dst) {
$FAIL($Fail);
}
header = *boxed_val(context);
- slots = $Slots;
+
+ /* Reserve a slot for the start position. */
+ slots = $Slots + 1;
live = $Live;
+
if (header_is_bin_matchstate(header)) {
ErlBinMatchState* ms = (ErlBinMatchState *) boxed_val(context);
Uint actual_slots = HEADER_NUM_SLOTS(header);
+
+ /* We're not compatible with contexts created by bs_start_match3. */
+ ASSERT(actual_slots >= 1);
+
ms->save_offset[0] = ms->mb.offset;
- if (actual_slots < slots) {
- ErlBinMatchState* dst;
+ if (ERTS_UNLIKELY(actual_slots < slots)) {
+ ErlBinMatchState* expanded;
Uint live = $Live;
Uint wordsneeded = ERL_BIN_MATCHSTATE_SIZE(slots);
-
$GC_TEST_PRESERVE(wordsneeded, live, context);
ms = (ErlBinMatchState *) boxed_val(context);
- dst = (ErlBinMatchState *) HTOP;
- *dst = *ms;
+ expanded = (ErlBinMatchState *) HTOP;
+ *expanded = *ms;
*HTOP = HEADER_BIN_MATCHSTATE(slots);
HTOP += wordsneeded;
HEAP_SPACE_VERIFIED(0);
- $Dst = make_matchstate(dst);
+ context = make_matchstate(expanded);
+ $REFRESH_GEN_DEST();
}
+ $Dst = context;
} else if (is_binary_header(header)) {
Eterm result;
Uint wordsneeded = ERL_BIN_MATCHSTATE_SIZE(slots);
@@ -758,6 +770,7 @@ bs_start_match.execute(Fail, Live, Slots, Dst) {
if (is_non_value(result)) {
$FAIL($Fail);
}
+ $REFRESH_GEN_DEST();
$Dst = result;
} else {
$FAIL($Fail);
@@ -906,6 +919,7 @@ i_bs_get_integer(Fail, Live, FlagsAndUnit, Ms, Sz, Dst) {
}
wordsneeded = 1+WSIZE(NBYTES((Uint) size));
$GC_TEST_PRESERVE(wordsneeded, $Live, ms);
+ $REFRESH_GEN_DEST();
}
mb = ms_matchbuffer(ms);
LIGHT_SWAPOUT;
@@ -939,6 +953,7 @@ i_bs_get_utf8(Ctx, Fail, Dst) {
if (is_non_value(result)) {
$FAIL($Fail);
}
+ $REFRESH_GEN_DEST();
$Dst = result;
}
@@ -949,6 +964,7 @@ i_bs_get_utf16(Ctx, Fail, Flags, Dst) {
if (is_non_value(result)) {
$FAIL($Fail);
}
+ $REFRESH_GEN_DEST();
$Dst = result;
}
@@ -1029,10 +1045,289 @@ i_bs_match_string(Ctx, Fail, Bits, Ptr) {
i_bs_save2(Src, Slot) {
ErlBinMatchState* _ms = (ErlBinMatchState*) boxed_val((Eterm) $Src);
+ ASSERT(HEADER_NUM_SLOTS(_ms->thing_word) > $Slot);
_ms->save_offset[$Slot] = _ms->mb.offset;
}
i_bs_restore2(Src, Slot) {
ErlBinMatchState* _ms = (ErlBinMatchState*) boxed_val((Eterm) $Src);
+ ASSERT(HEADER_NUM_SLOTS(_ms->thing_word) > $Slot);
_ms->mb.offset = _ms->save_offset[$Slot];
}
+
+bs_get_tail(Src, Dst, Live) {
+ ErlBinMatchBuffer* mb;
+ Uint size, offs;
+ ErlSubBin* sb;
+ Eterm context;
+
+ context = $Src;
+
+ ASSERT(header_is_bin_matchstate(*boxed_val(context)));
+
+ $GC_TEST_PRESERVE(ERL_SUB_BIN_SIZE, $Live, context);
+
+ mb = ms_matchbuffer(context);
+
+ offs = mb->offset;
+ size = mb->size - offs;
+
+ sb = (ErlSubBin *) HTOP;
+ HTOP += ERL_SUB_BIN_SIZE;
+
+ sb->thing_word = HEADER_SUB_BIN;
+ sb->size = BYTE_OFFSET(size);
+ sb->bitsize = BIT_OFFSET(size);
+ sb->offs = BYTE_OFFSET(offs);
+ sb->bitoffs = BIT_OFFSET(offs);
+ sb->is_writable = 0;
+ sb->orig = mb->orig;
+
+ $REFRESH_GEN_DEST();
+ $Dst = make_binary(sb);
+}
+
+
+%if ARCH_64
+
+i_bs_start_match3_gp(Src, Live, Fail, Dst, Pos) {
+ Eterm context, header;
+ Uint position, live;
+
+ context = $Src;
+ live = $Live;
+
+ if (!is_boxed(context)) {
+ $FAIL($Fail);
+ }
+
+ header = *boxed_val(context);
+
+ if (header_is_bin_matchstate(header)) {
+ ErlBinMatchBuffer *mb;
+
+ ASSERT(HEADER_NUM_SLOTS(header) == 0);
+
+ mb = ms_matchbuffer(context);
+ position = mb->offset;
+
+ $Dst = context;
+ } else if (is_binary_header(header)) {
+ ErlBinMatchState *ms;
+
+ $GC_TEST_PRESERVE(ERL_BIN_MATCHSTATE_SIZE(0), live, context);
+ HEAP_TOP(c_p) = HTOP;
+#ifdef DEBUG
+ c_p->stop = E; /* Needed for checking in HeapOnlyAlloc(). */
+#endif
+ ms = erts_bs_start_match_3(c_p, context);
+ HTOP = HEAP_TOP(c_p);
+ HEAP_SPACE_VERIFIED(0);
+
+ if (ms == NULL) {
+ $FAIL($Fail);
+ }
+
+ $REFRESH_GEN_DEST();
+ $Dst = make_matchstate(ms);
+ position = ms->mb.offset;
+ } else {
+ $FAIL($Fail);
+ }
+
+ ASSERT(IS_USMALL(0, position));
+ $Pos = make_small(position);
+}
+
+i_bs_start_match3(Src, Live, Fail, Dst) {
+ Eterm context, header;
+ Uint live;
+
+ context = $Src;
+ live = $Live;
+
+ if (!is_boxed(context)) {
+ $FAIL($Fail);
+ }
+
+ header = *boxed_val(context);
+
+ if (header_is_bin_matchstate(header)) {
+ ASSERT(HEADER_NUM_SLOTS(header) == 0);
+ $Dst = context;
+ } else if (is_binary_header(header)) {
+ ErlBinMatchState *ms;
+
+ $GC_TEST_PRESERVE(ERL_BIN_MATCHSTATE_SIZE(0), live, context);
+ HEAP_TOP(c_p) = HTOP;
+#ifdef DEBUG
+ c_p->stop = E; /* Needed for checking in HeapOnlyAlloc(). */
+#endif
+ ms = erts_bs_start_match_3(c_p, context);
+ HTOP = HEAP_TOP(c_p);
+ HEAP_SPACE_VERIFIED(0);
+
+ if (ms == NULL) {
+ $FAIL($Fail);
+ }
+
+ $REFRESH_GEN_DEST();
+ $Dst = make_matchstate(ms);
+ } else {
+ $FAIL($Fail);
+ }
+}
+
+bs_set_position(Ctx, Pos) {
+ ErlBinMatchBuffer* mb;
+ Eterm context;
+
+ context = $Ctx;
+ ASSERT(header_is_bin_matchstate(*boxed_val(context)));
+
+ mb = ms_matchbuffer(context);
+ mb->offset = unsigned_val($Pos);
+}
+
+i_bs_get_position(Ctx, Dst) {
+ ErlBinMatchBuffer* mb;
+ Eterm context;
+
+ context = $Ctx;
+ ASSERT(header_is_bin_matchstate(*boxed_val(context)));
+
+ mb = ms_matchbuffer(context);
+ $Dst = make_small(mb->offset);
+}
+
+%else
+
+#
+# Unlike their 64-bit counterparts, the 32-bit position instructions operate on
+# an offset from the "base position" of the context because storing raw
+# positions would lead to the creation of far too many bigints.
+#
+# When a match context is reused we check whether its position fits into an
+# immediate, and create a new match context if it does not. This means we only
+# have to allocate stuff roughly once every 16MB rather than every time we
+# match at a position beyond 16MB.
+#
+
+bs_set_position(Ctx, Pos) {
+ Eterm context, position;
+ ErlBinMatchState *ms;
+
+ context = $Ctx;
+ position = $Pos;
+
+ ASSERT(header_is_bin_matchstate(*boxed_val(context)));
+ ms = (ErlBinMatchState*)boxed_val(context);
+
+ if (ERTS_LIKELY(is_small(position))) {
+ ms->mb.offset = ms->save_offset[0] + unsigned_val(position);
+ } else {
+ ASSERT(is_big(position));
+ ms->mb.offset = ms->save_offset[0] + *BIG_V(big_val(position));
+ }
+}
+
+bs_get_position(Ctx, Dst, Live) {
+ ErlBinMatchState *ms;
+ Eterm context;
+ Uint position;
+
+ context = $Ctx;
+
+ ASSERT(header_is_bin_matchstate(*boxed_val(context)));
+ ms = (ErlBinMatchState*)boxed_val(context);
+
+ position = ms->mb.offset - ms->save_offset[0];
+
+ if (ERTS_LIKELY(IS_USMALL(0, position))) {
+ $Dst = make_small(position);
+ } else {
+ Eterm *hp;
+
+ $GC_TEST_PRESERVE(BIG_UINT_HEAP_SIZE, $Live, context);
+
+ hp = HTOP;
+ HTOP += BIG_UINT_HEAP_SIZE;
+
+ *hp = make_pos_bignum_header(1);
+ BIG_DIGIT(hp, 0) = position;
+
+ $REFRESH_GEN_DEST();
+ $Dst = make_big(hp);
+ }
+}
+
+i_bs_start_match3(Src, Live, Fail, Dst) {
+ Eterm context, header;
+ Uint live;
+
+ context = $Src;
+ live = $Live;
+
+ if (!is_boxed(context)) {
+ $FAIL($Fail);
+ }
+
+ header = *boxed_val(context);
+
+ if (header_is_bin_matchstate(header)) {
+ ErlBinMatchState *current_ms;
+ Uint position;
+
+ ASSERT(HEADER_NUM_SLOTS(header) == 1);
+
+ current_ms = (ErlBinMatchState*)boxed_val(context);
+ position = current_ms->mb.offset - current_ms->save_offset[0];
+
+ if (ERTS_LIKELY(IS_USMALL(0, position))) {
+ $Dst = context;
+ } else {
+ ErlBinMatchState *new_ms;
+
+ $GC_TEST_PRESERVE(ERL_BIN_MATCHSTATE_SIZE(1), live, context);
+ current_ms = (ErlBinMatchState*)boxed_val(context);
+
+ new_ms = (ErlBinMatchState*)HTOP;
+ HTOP += ERL_BIN_MATCHSTATE_SIZE(1);
+
+ new_ms->thing_word = HEADER_BIN_MATCHSTATE(1);
+ new_ms->save_offset[0] = current_ms->mb.offset;
+ new_ms->mb = current_ms->mb;
+
+ $REFRESH_GEN_DEST();
+ $Dst = make_matchstate(new_ms);
+ }
+ } else if (is_binary_header(header)) {
+ Eterm result;
+
+ $GC_TEST_PRESERVE(ERL_BIN_MATCHSTATE_SIZE(1), live, context);
+ HEAP_TOP(c_p) = HTOP;
+
+#ifdef DEBUG
+ c_p->stop = E; /* Needed for checking in HeapOnlyAlloc(). */
+#endif
+
+ /* We intentionally use erts_bs_start_match_2 so that we can use
+ * save_offset as a base for all saved positions on this context,
+ * allowing us to avoid bigints for much longer. */
+ result = erts_bs_start_match_2(c_p, context, 1);
+
+ HTOP = HEAP_TOP(c_p);
+ HEAP_SPACE_VERIFIED(0);
+
+ if (is_non_value(result)) {
+ $FAIL($Fail);
+ }
+
+ $REFRESH_GEN_DEST();
+ $Dst = result;
+ } else {
+ $FAIL($Fail);
+ }
+}
+
+%endif
diff --git a/erts/emulator/beam/erl_bits.c b/erts/emulator/beam/erl_bits.c
index 3a16913473..e82c776e70 100644
--- a/erts/emulator/beam/erl_bits.c
+++ b/erts/emulator/beam/erl_bits.c
@@ -144,6 +144,42 @@ erts_bs_start_match_2(Process *p, Eterm Binary, Uint Max)
return make_matchstate(ms);
}
+ErlBinMatchState *erts_bs_start_match_3(Process *p, Eterm Binary)
+{
+ Eterm Orig;
+ Uint offs;
+ Uint* hp;
+ Uint NeededSize;
+ ErlBinMatchState *ms;
+ Uint bitoffs;
+ Uint bitsize;
+ Uint total_bin_size;
+ ProcBin* pb;
+
+ ASSERT(is_binary(Binary));
+ total_bin_size = binary_size(Binary);
+ if ((total_bin_size >> (8*sizeof(Uint)-3)) != 0) {
+ return NULL;
+ }
+
+ NeededSize = ERL_BIN_MATCHSTATE_SIZE(0);
+ hp = HeapOnlyAlloc(p, NeededSize);
+ ms = (ErlBinMatchState *) hp;
+ ERTS_GET_REAL_BIN(Binary, Orig, offs, bitoffs, bitsize);
+ pb = (ProcBin *) boxed_val(Orig);
+ if (pb->thing_word == HEADER_PROC_BIN && pb->flags != 0) {
+ erts_emasculate_writable_binary(pb);
+ }
+
+ ms->thing_word = HEADER_BIN_MATCHSTATE(0);
+ (ms->mb).orig = Orig;
+ (ms->mb).base = binary_bytes(Orig);
+ (ms->mb).offset = 8 * offs + bitoffs;
+ (ms->mb).size = total_bin_size * 8 + (ms->mb).offset + bitsize;
+
+ return ms;
+}
+
#ifdef DEBUG
# define CHECK_MATCH_BUFFER(MB) check_match_buffer(MB)
diff --git a/erts/emulator/beam/erl_bits.h b/erts/emulator/beam/erl_bits.h
index 7beef5cfda..50d353e1fa 100644
--- a/erts/emulator/beam/erl_bits.h
+++ b/erts/emulator/beam/erl_bits.h
@@ -73,12 +73,16 @@ struct erl_bits_state {
typedef struct erl_bin_match_struct{
Eterm thing_word;
ErlBinMatchBuffer mb; /* Present match buffer */
- Eterm save_offset[1]; /* Saved offsets */
+ Eterm save_offset[1]; /* Saved offsets, only valid for contexts
+ * created through bs_start_match2. */
} ErlBinMatchState;
-#define ERL_BIN_MATCHSTATE_SIZE(_Max) ((sizeof(ErlBinMatchState) + (_Max)*sizeof(Eterm))/sizeof(Eterm))
-#define HEADER_BIN_MATCHSTATE(_Max) _make_header(ERL_BIN_MATCHSTATE_SIZE((_Max))-1, _TAG_HEADER_BIN_MATCHSTATE)
-#define HEADER_NUM_SLOTS(hdr) (header_arity(hdr)-sizeof(ErlBinMatchState)/sizeof(Eterm)+1)
+#define ERL_BIN_MATCHSTATE_SIZE(_Max) \
+ ((offsetof(ErlBinMatchState, save_offset) + (_Max)*sizeof(Eterm))/sizeof(Eterm))
+#define HEADER_BIN_MATCHSTATE(_Max) \
+ _make_header(ERL_BIN_MATCHSTATE_SIZE((_Max)) - 1, _TAG_HEADER_BIN_MATCHSTATE)
+#define HEADER_NUM_SLOTS(hdr) \
+ (header_arity(hdr) - (offsetof(ErlBinMatchState, save_offset) / sizeof(Eterm)) + 1)
#define make_matchstate(_Ms) make_boxed((Eterm*)(_Ms))
#define ms_matchbuffer(_Ms) &(((ErlBinMatchState*) boxed_val(_Ms))->mb)
@@ -144,6 +148,7 @@ void erts_bits_destroy_state(ERL_BITS_PROTO_0);
*/
Eterm erts_bs_start_match_2(Process *p, Eterm Bin, Uint Max);
+ErlBinMatchState *erts_bs_start_match_3(Process *p, Eterm Bin);
Eterm erts_bs_get_integer_2(Process *p, Uint num_bits, unsigned flags, ErlBinMatchBuffer* mb);
Eterm erts_bs_get_binary_2(Process *p, Uint num_bits, unsigned flags, ErlBinMatchBuffer* mb);
Eterm erts_bs_get_float_2(Process *p, Uint num_bits, unsigned flags, ErlBinMatchBuffer* mb);
diff --git a/erts/emulator/beam/ops.tab b/erts/emulator/beam/ops.tab
index d859c4bb24..349034e8ac 100644
--- a/erts/emulator/beam/ops.tab
+++ b/erts/emulator/beam/ops.tab
@@ -1089,21 +1089,21 @@ func_info M F A => i_func_info u M F A
%warm
bs_start_match2 Fail=f ica X Y D => jump Fail
bs_start_match2 Fail Bin X Y D => i_bs_start_match2 Bin Fail X Y D
-i_bs_start_match2 xy f t t x
+i_bs_start_match2 xy f t t d
bs_save2 Reg Index => gen_bs_save(Reg, Index)
-i_bs_save2 x t
+i_bs_save2 xy t
bs_restore2 Reg Index => gen_bs_restore(Reg, Index)
-i_bs_restore2 x t
+i_bs_restore2 xy t
# Matching integers
bs_match_string Fail Ms Bits Val => i_bs_match_string Ms Fail Bits Val
-i_bs_match_string x f W W
+i_bs_match_string xy f W W
# Fetching integers from binaries.
-bs_get_integer2 Fail=f Ms=x Live=u Sz=sq Unit=u Flags=u Dst=d => \
+bs_get_integer2 Fail=f Ms=xy Live=u Sz=sq Unit=u Flags=u Dst=d => \
gen_get_integer2(Fail, Ms, Live, Sz, Unit, Flags, Dst)
i_bs_get_integer_small_imm Ms Bits Fail Flags Y=y => \
@@ -1112,50 +1112,50 @@ i_bs_get_integer_small_imm Ms Bits Fail Flags Y=y => \
i_bs_get_integer_imm Ms Bits Live Fail Flags Y=y => \
i_bs_get_integer_imm Ms Bits Live Fail Flags x | move x Y
-i_bs_get_integer_small_imm x W f? t x
-i_bs_get_integer_imm x W t f? t x
-i_bs_get_integer f? t t x s xy
-i_bs_get_integer_8 x f? xy
-i_bs_get_integer_16 x f? xy
+i_bs_get_integer_small_imm xy W f? t x
+i_bs_get_integer_imm xy W t f? t x
+i_bs_get_integer f? t t xy s d
+i_bs_get_integer_8 xy f? d
+i_bs_get_integer_16 xy f? d
%if ARCH_64
-i_bs_get_integer_32 x f? xy
+i_bs_get_integer_32 xy f? d
%endif
# Fetching binaries from binaries.
-bs_get_binary2 Fail=f Ms=x Live=u Sz=sq Unit=u Flags=u Dst=d => \
+bs_get_binary2 Fail=f Ms=xy Live=u Sz=sq Unit=u Flags=u Dst=d => \
gen_get_binary2(Fail, Ms, Live, Sz, Unit, Flags, Dst)
-i_bs_get_binary_imm2 f? x t W t xy
-i_bs_get_binary2 f x t? s t xy
-i_bs_get_binary_all2 f? x t t xy
-i_bs_get_binary_all_reuse x f? t
+i_bs_get_binary_imm2 f? xy t W t d
+i_bs_get_binary2 f xy t? s t d
+i_bs_get_binary_all2 f? xy t t d
+i_bs_get_binary_all_reuse xy f? t
# Fetching float from binaries.
-bs_get_float2 Fail=f Ms=x Live=u Sz=s Unit=u Flags=u Dst=d => \
+bs_get_float2 Fail=f Ms=xy Live=u Sz=s Unit=u Flags=u Dst=d => \
gen_get_float2(Fail, Ms, Live, Sz, Unit, Flags, Dst)
bs_get_float2 Fail=f Ms=x Live=u Sz=q Unit=u Flags=u Dst=d => jump Fail
-i_bs_get_float2 f? x t s t xy
+i_bs_get_float2 f? xy t s t d
# Miscellanous
-bs_skip_bits2 Fail=f Ms=x Sz=sq Unit=u Flags=u => \
+bs_skip_bits2 Fail=f Ms=xy Sz=sq Unit=u Flags=u => \
gen_skip_bits2(Fail, Ms, Sz, Unit, Flags)
-i_bs_skip_bits_imm2 f? x W
-i_bs_skip_bits2 f? x xy t
-i_bs_skip_bits_all2 f? x t
+i_bs_skip_bits_imm2 f? xy W
+i_bs_skip_bits2 f? xy xy t
+i_bs_skip_bits_all2 f? xy t
-bs_test_tail2 Fail=f Ms=x Bits=u==0 => bs_test_zero_tail2 Fail Ms
-bs_test_tail2 Fail=f Ms=x Bits=u => bs_test_tail_imm2 Fail Ms Bits
-bs_test_zero_tail2 f? x
-bs_test_tail_imm2 f? x W
+bs_test_tail2 Fail=f Ms=xy Bits=u==0 => bs_test_zero_tail2 Fail Ms
+bs_test_tail2 Fail=f Ms=xy Bits=u => bs_test_tail_imm2 Fail Ms Bits
+bs_test_zero_tail2 f? xy
+bs_test_tail_imm2 f? xy W
bs_test_unit F Ms Unit=u==8 => bs_test_unit8 F Ms
-bs_test_unit f? x t
-bs_test_unit8 f? x
+bs_test_unit f? xy t
+bs_test_unit8 f? xy
# An y register operand for bs_context_to_binary is rare,
# but can happen because of inlining.
@@ -1167,23 +1167,55 @@ bs_context_to_binary Y=y => move Y x | bs_context_to_binary x
bs_context_to_binary x
+# Gets a bitstring from the tail of a context.
+bs_get_tail xy d t
+
+# New bs_start_match variant for contexts with external position storage.
+#
+# bs_get/set_position is used to save positions into registers instead of
+# "slots" in the context itself, which lets us continue matching even after
+# we've passed it off to another function.
+
+%if ARCH_64
+bs_start_match3 Fail Bin Live Ctx | bs_get_position Ctx Pos=x Ignored => \
+ i_bs_start_match3_gp Bin Live Fail Ctx Pos
+i_bs_start_match3_gp xy t f d x
+%endif
+
+bs_start_match3 Fail=f ica Live Dst => jump Fail
+bs_start_match3 Fail Bin Live Dst => i_bs_start_match3 Bin Live Fail Dst
+
+i_bs_start_match3 xy t f d
+
+# Match context position instructions. 64-bit assumes that all positions can
+# fit into an unsigned small.
+
+%if ARCH_64
+ bs_get_position Src Dst Live => i_bs_get_position Src Dst
+ i_bs_get_position xy xy
+ bs_set_position xy xy
+%else
+ bs_get_position xy d t?
+ bs_set_position xy xy
+%endif
+
#
# Utf8/utf16/utf32 support. (R12B-5)
#
-bs_get_utf8 Fail=f Ms=x u u Dst=d => i_bs_get_utf8 Ms Fail Dst
-i_bs_get_utf8 x f? xy
+bs_get_utf8 Fail=f Ms=xy u u Dst=d => i_bs_get_utf8 Ms Fail Dst
+i_bs_get_utf8 xy f? d
-bs_skip_utf8 Fail=f Ms=x u u => i_bs_get_utf8 Ms Fail x
+bs_skip_utf8 Fail=f Ms=xy u u => i_bs_get_utf8 Ms Fail x
-bs_get_utf16 Fail=f Ms=x u Flags=u Dst=d => i_bs_get_utf16 Ms Fail Flags Dst
-bs_skip_utf16 Fail=f Ms=x u Flags=u => i_bs_get_utf16 Ms Fail Flags x
+bs_get_utf16 Fail=f Ms=xy u Flags=u Dst=d => i_bs_get_utf16 Ms Fail Flags Dst
+bs_skip_utf16 Fail=f Ms=xy u Flags=u => i_bs_get_utf16 Ms Fail Flags x
-i_bs_get_utf16 x f? t xy
+i_bs_get_utf16 xy f? t d
-bs_get_utf32 Fail=f Ms=x Live=u Flags=u Dst=d => \
+bs_get_utf32 Fail=f Ms=xy Live=u Flags=u Dst=d => \
bs_get_integer2 Fail Ms Live i=32 u=1 Flags Dst | \
i_bs_validate_unicode_retract Fail Dst Ms
-bs_skip_utf32 Fail=f Ms=x Live=u Flags=u => \
+bs_skip_utf32 Fail=f Ms=xy Live=u Flags=u => \
bs_get_integer2 Fail Ms Live i=32 u=1 Flags x | \
i_bs_validate_unicode_retract Fail x Ms
diff --git a/lib/compiler/src/Makefile b/lib/compiler/src/Makefile
index 522523726b..26ae6566e6 100644
--- a/lib/compiler/src/Makefile
+++ b/lib/compiler/src/Makefile
@@ -50,7 +50,6 @@ MODULES = \
beam_asm \
beam_block \
beam_bs \
- beam_bsm \
beam_clean \
beam_dict \
beam_disasm \
@@ -61,6 +60,7 @@ MODULES = \
beam_opcodes \
beam_peep \
beam_ssa \
+ beam_ssa_bsm \
beam_ssa_codegen \
beam_ssa_dead \
beam_ssa_lint \
diff --git a/lib/compiler/src/beam_bsm.erl b/lib/compiler/src/beam_bsm.erl
deleted file mode 100644
index abc6e96c85..0000000000
--- a/lib/compiler/src/beam_bsm.erl
+++ /dev/null
@@ -1,719 +0,0 @@
-%%
-%% %CopyrightBegin%
-%%
-%% Copyright Ericsson AB 2007-2018. All Rights Reserved.
-%%
-%% Licensed under the Apache License, Version 2.0 (the "License");
-%% you may not use this file except in compliance with the License.
-%% You may obtain a copy of the License at
-%%
-%% http://www.apache.org/licenses/LICENSE-2.0
-%%
-%% Unless required by applicable law or agreed to in writing, software
-%% distributed under the License is distributed on an "AS IS" BASIS,
-%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-%% See the License for the specific language governing permissions and
-%% limitations under the License.
-%%
-%% %CopyrightEnd%
-%%
-
--module(beam_bsm).
--export([module/2,format_error/1]).
-
--import(lists, [member/2,foldl/3,reverse/1,sort/1,all/2]).
-
-%%%
-%%% We optimize bit syntax matching where the tail end of a binary is
-%%% matched out and immediately passed on to a bs_start_match2 instruction,
-%%% such as in this code sequence:
-%%%
-%%% func_info ...
-%%% L1 test bs_start_match2 {f,...} {x,0} Live SavePositions {x,0}
-%%% . . .
-%%% test bs_get_binary2 {f,...} {x,0} all 1 Flags {x,0}
-%%% . . .
-%%% call_only 2 L1
-%%%
-%%% The sequence can be optimized simply by removing the bs_get_binary2
-%%% instruction. Another example:
-%%%
-%%% func_info ...
-%%% L1 test bs_start_match2 {f,...} {x,0} Live SavePositions {x,0}
-%%% . . .
-%%% test bs_get_binary2 {f,...} {x,0} all 8 Flags {x,1}
-%%% . . .
-%%% move {x,1} {x,0}
-%%% call_only 2 L1
-%%%
-%%% In this case, the bs_get_binary2 instruction must be replaced by
-%%%
-%%% test bs_unit {x,1} 8
-%%%
-%%% to ensure that the match fail if the length of the binary in bits
-%%% is not evenly divisible by 8.
-%%%
-%%% Note that the bs_start_match2 instruction doesn't need to be in the same
-%%% function as the caller. It can be in the beginning of any function, or
-%%% follow the bs_get_binary2 instruction in the same function. The important
-%%% thing is that the match context register is not copied or built into
-%%% data structures or passed to BIFs.
-%%%
-
--type label() :: beam_asm:label().
--type func_info() :: {beam_asm:reg(),boolean()}.
-
--record(btb,
- {f :: gb_trees:tree(label(), func_info()),
- index :: beam_utils:code_index(), %{Label,Code} index (for liveness).
- ok_br=gb_sets:empty() :: gb_sets:set(label()), %Labels that are OK.
- must_not_save=false :: boolean(), %Must not save position when
- % optimizing (reaches
- % bs_context_to_binary).
- must_save=false :: boolean() %Must save position when optimizing.
- }).
-
-
--spec module(beam_utils:module_code(), [compile:option()]) ->
- {'ok',beam_utils:module_code()}.
-
-module({Mod,Exp,Attr,Fs0,Lc}, Opts) ->
- FIndex = btb_index(Fs0),
- Fs = [function(F, FIndex) || F <- Fs0],
- Code = {Mod,Exp,Attr,Fs,Lc},
- case proplists:get_bool(bin_opt_info, Opts) of
- true ->
- {ok,Code,collect_warnings(Fs)};
- false ->
- {ok,Code}
- end.
-
--spec format_error('bin_opt' | {'no_bin_opt', term()}) -> nonempty_string().
-
-format_error(bin_opt) ->
- "OPTIMIZED: creation of sub binary delayed";
-format_error({no_bin_opt,Reason}) ->
- lists:flatten(["NOT OPTIMIZED: "|format_error_1(Reason)]).
-
-%%%
-%%% Local functions.
-%%%
-
-function({function,Name,Arity,Entry,Is}, FIndex) ->
- try
- Index = beam_utils:index_labels(Is),
- D = #btb{f=FIndex,index=Index},
- {function,Name,Arity,Entry,btb_opt_1(Is, D, [])}
- catch
- Class:Error:Stack ->
- io:fwrite("Function: ~w/~w\n", [Name,Arity]),
- erlang:raise(Class, Error, Stack)
- end.
-
-btb_opt_1([{test,bs_get_binary2,F,_,[Reg,{atom,all},U,Fs],Reg}=I0|Is], D, Acc0) ->
- case btb_reaches_match(Is, [Reg], D) of
- {error,Reason} ->
- Comment = btb_comment_no_opt(Reason, Fs),
- btb_opt_1(Is, D, [Comment,I0|Acc0]);
- {ok,MustSave} ->
- Comment = btb_comment_opt(Fs),
- Acc1 = btb_gen_save(MustSave, Reg, [Comment|Acc0]),
- Acc = case U of
- 1 -> Acc1;
- _ -> [{test,bs_test_unit,F,[Reg,U]}|Acc1]
- end,
- btb_opt_1(Is, D, Acc)
- end;
-btb_opt_1([{test,bs_get_binary2,F,_,[Ctx,{atom,all},U,Fs],Dst}=I0|Is0], D, Acc0) ->
- case btb_reaches_match(Is0, [Ctx,Dst], D) of
- {error,Reason} ->
- Comment = btb_comment_no_opt(Reason, Fs),
- btb_opt_1(Is0, D, [Comment,I0|Acc0]);
- {ok,MustSave} when U =:= 1 ->
- Comment = btb_comment_opt(Fs),
- Acc = btb_gen_save(MustSave, Ctx, [Comment|Acc0]),
- Is = prepend_move(Ctx, Dst, Is0),
- btb_opt_1(Is, D, Acc);
- {ok,MustSave} ->
- Comment = btb_comment_opt(Fs),
- Acc1 = btb_gen_save(MustSave, Ctx, [Comment|Acc0]),
- Acc = [{test,bs_test_unit,F,[Ctx,U]}|Acc1],
- Is = prepend_move(Ctx, Dst, Is0),
- btb_opt_1(Is, D, Acc)
- end;
-btb_opt_1([I|Is], D, Acc) ->
- %%io:format("~p\n", [I]),
- btb_opt_1(Is, D, [I|Acc]);
-btb_opt_1([], _, Acc) ->
- reverse(Acc).
-
-btb_gen_save(true, Reg, Acc) ->
- [{bs_save2,Reg,{atom,start}}|Acc];
-btb_gen_save(false, _, Acc) -> Acc.
-
-prepend_move(Ctx, Dst, [{block,Bl0}|Is]) ->
- Bl = [{set,[Dst],[Ctx],move}|Bl0],
- [{block,Bl}|Is];
-prepend_move(Ctx, Dst, Is) ->
- [{move,Ctx,Dst}|Is].
-
-%% btb_reaches_match([Instruction], [Register], D) ->
-%% {ok,MustSave}|{error,Reason}
-%%
-%% The list of Registers should be a list of registers referencing a
-%% match context. The Register may contain one element if the
-%% bs_get_binary2 instruction looks like
-%%
-%% test bs_get_binary2 {f,...} Ctx all _ _ Ctx
-%%
-%% or two elements if the instruction looks like
-%%
-%% test bs_get_binary2 {f,...} Ctx all _ _ Dst
-%%
-%% This function determines whether the bs_get_binary2 instruction
-%% can be omitted (retaining the match context instead of creating
-%% a sub binary).
-%%
-%% The rule is that the match context ultimately must end up at a
-%% bs_start_match2 instruction and nowhere else. That it, it must not
-%% be passed to BIFs, or copied or put into data structures. There
-%% must only be one copy alive when the match context reaches the
-%% bs_start_match2 instruction.
-%%
-%% At a branch, we must follow all branches and make sure that the above
-%% rule is followed (or that the branch kills the match context).
-%%
-%% The MustSave return value will be true if control may end up at
-%% bs_context_to_binary instruction. Since that instruction uses the
-%% saved start position, we must use "bs_save2 Ctx start" to
-%% update the saved start position. An additional complication is that
-%% "bs_save2 Ctx start" must not be used if Dst and Ctx are
-%% different registers and both registers may be passed to
-%% a bs_context_to_binary instruction.
-%%
-
-btb_reaches_match(Is, RegList, D) ->
- try
- Regs = btb_regs_from_list(RegList),
- #btb{must_not_save=MustNotSave,must_save=MustSave} =
- btb_reaches_match_1(Is, Regs, D),
- case MustNotSave andalso MustSave of
- true -> btb_error(must_and_must_not_save);
- false -> {ok,MustSave}
- end
- catch
- throw:{error,_}=Error -> Error
- end.
-
-btb_reaches_match_1(Is, Regs, D) ->
- case btb_are_registers_empty(Regs) of
- false ->
- btb_reaches_match_2(Is, Regs, D);
- true ->
- %% The context was killed, which is OK.
- D
- end.
-
-btb_reaches_match_2([{block,Bl}|Is], Regs0, D) ->
- Regs = btb_reaches_match_block(Bl, Regs0),
- btb_reaches_match_1(Is, Regs, D);
-btb_reaches_match_2([{call,Arity,{f,Lbl}}|Is], Regs0, D) ->
- case is_tail_call(Is) of
- true ->
- Regs1 = btb_kill_not_live(Arity, Regs0),
- Regs = btb_kill_yregs(Regs1),
- btb_tail_call(Lbl, Regs, D);
- false ->
- btb_call(Arity, Lbl, Regs0, Is, D)
- end;
-btb_reaches_match_2([{apply,Arity}|Is], Regs, D) ->
- btb_call(Arity+2, apply, Regs, Is, D);
-btb_reaches_match_2([{call_fun,Live}=I|Is], Regs, D) ->
- btb_ensure_not_used([{x,Live}], I, Regs),
- btb_call(Live, I, Regs, Is, D);
-btb_reaches_match_2([{make_fun2,_,_,_,Live}|Is], Regs, D) ->
- btb_call(Live, make_fun2, Regs, Is, D);
-btb_reaches_match_2([{call_ext,Arity,Func}=I|Is], Regs0, D) ->
- %% Allow us scanning beyond the call in case the match
- %% context is saved on the stack.
- case beam_jump:is_exit_instruction(I) of
- false ->
- btb_call(Arity, Func, Regs0, Is, D);
- true ->
- Regs = btb_kill_not_live(Arity, Regs0),
- btb_tail_call(Func, Regs, D)
- end;
-btb_reaches_match_2([{kill,Y}|Is], Regs, D) ->
- btb_reaches_match_1(Is, btb_kill([Y], Regs), D);
-btb_reaches_match_2([{deallocate,_}|Is], Regs0, D) ->
- Regs = btb_kill_yregs(Regs0),
- btb_reaches_match_1(Is, Regs, D);
-btb_reaches_match_2([return=I|_], Regs0, D) ->
- btb_ensure_not_used([{x,0}], I, Regs0),
- D;
-btb_reaches_match_2([{gc_bif,_,{f,F},Live,Ss,Dst}=I|Is], Regs0, D0) ->
- btb_ensure_not_used(Ss, I, Regs0),
- Regs1 = btb_kill_not_live(Live, Regs0),
- Regs = btb_kill([Dst], Regs1),
- D = btb_follow_branch(F, Regs, D0),
- btb_reaches_match_1(Is, Regs, D);
-btb_reaches_match_2([{bif,_,{f,F},Ss,Dst}=I|Is], Regs0, D0) ->
- btb_ensure_not_used(Ss, I, Regs0),
- Regs = btb_kill([Dst], Regs0),
- D = btb_follow_branch(F, Regs, D0),
- btb_reaches_match_1(Is, Regs, D);
-btb_reaches_match_2([{get_map_elements,{f,F},Src,{list,Ls}}=I|Is], Regs0, D0) ->
- {Ss,Ds} = beam_utils:split_even(Ls),
- btb_ensure_not_used([Src|Ss], I, Regs0),
- Regs = btb_kill(Ds, Regs0),
- D = btb_follow_branch(F, Regs, D0),
- btb_reaches_match_1(Is, Regs, D);
-btb_reaches_match_2([{test,bs_start_match2,{f,F},Live,[Ctx,_],Ctx}=I|Is],
- Regs0, D0) ->
- CtxRegs = btb_context_regs(Regs0),
- case member(Ctx, CtxRegs) of
- false ->
- %% This bs_start_match2 instruction does not use "our"
- %% match state. Therefore we can continue the search
- %% for another bs_start_match2 instruction.
- D = btb_follow_branch(F, Regs0, D0),
- Regs = btb_kill_not_live(Live, Regs0),
- btb_reaches_match_2(Is, Regs, D);
- true ->
- %% OK. This instruction will use "our" match state,
- %% but we must make sure that all other copies of the
- %% match state are killed in the code that follows
- %% the instruction. (We know that the fail branch cannot
- %% be taken in this case.)
- OtherCtxRegs = CtxRegs -- [Ctx],
- case btb_are_all_unused(OtherCtxRegs, Is, D0) of
- false -> btb_error({OtherCtxRegs,not_all_unused_after,I});
- true -> D0
- end
- end;
-btb_reaches_match_2([{test,bs_start_match2,{f,F},Live,[Bin,_],Ctx}|Is],
- Regs0, D0) ->
- CtxRegs = btb_context_regs(Regs0),
- case member(Bin, CtxRegs) orelse member(Ctx, CtxRegs) of
- false ->
- %% This bs_start_match2 does not reference any copy of the
- %% match state. Therefore it can safely be passed on the
- %% way to another (perhaps more suitable) bs_start_match2
- %% instruction.
- D = btb_follow_branch(F, Regs0, D0),
- Regs = btb_kill_not_live(Live, Regs0),
- btb_reaches_match_2(Is, Regs, D);
- true ->
- %% This variant of the bs_start_match2 instruction does
- %% not accept a match state as source.
- btb_error(unsuitable_bs_start_match)
- end;
-btb_reaches_match_2([{test,_,{f,F},Ss}=I|Is], Regs, D0) ->
- btb_ensure_not_used(Ss, I, Regs),
- D1 = btb_follow_branch(F, Regs, D0),
- D = case Is of
- [{bs_context_to_binary,_}|_] ->
- %% bs_context_to_binary following a test instruction
- %% probably needs the current position to be saved as
- %% the new start position, but we can't be sure.
- %% Therefore, conservatively disable the optimization
- %% (instead of forcing a saving of the position).
- D1#btb{must_save=true,must_not_save=true};
- _ ->
- D1
- end,
- btb_reaches_match_1(Is, Regs, D);
-btb_reaches_match_2([{test,_,{f,F},_,Ss,_}=I|Is], Regs, D0) ->
- btb_ensure_not_used(Ss, I, Regs),
- D = btb_follow_branch(F, Regs, D0),
- btb_reaches_match_1(Is, Regs, D);
-btb_reaches_match_2([{select,_,Src,{f,F},Conds}=I|Is], Regs, D0) ->
- btb_ensure_not_used([Src], I, Regs),
- D1 = btb_follow_branch(F, Regs, D0),
- D = btb_follow_branches(Conds, Regs, D1),
- btb_reaches_match_1(Is, Regs, D);
-btb_reaches_match_2([{jump,{f,Lbl}}|_], Regs, #btb{index=Li}=D) ->
- Is = fetch_code_at(Lbl, Li),
- btb_reaches_match_2(Is, Regs, D);
-btb_reaches_match_2([{label,_}|Is], Regs, D) ->
- btb_reaches_match_2(Is, Regs, D);
-btb_reaches_match_2([{bs_init,{f,0},_,_,Ss,Dst}=I|Is], Regs, D) ->
- btb_ensure_not_used(Ss, I, Regs),
- btb_reaches_match_1(Is, btb_kill([Dst], Regs), D);
-btb_reaches_match_2([{bs_put,{f,0},_,Ss}=I|Is], Regs, D) ->
- btb_ensure_not_used(Ss, I, Regs),
- btb_reaches_match_1(Is, Regs, D);
-btb_reaches_match_2([{bs_restore2,Src,_}=I|Is], Regs0, D) ->
- case btb_contains_context(Src, Regs0) of
- false ->
- btb_reaches_match_1(Is, Regs0, D);
- true ->
- %% Check that all other copies of the context registers
- %% are unused by the following instructions.
- Regs = btb_kill([Src], Regs0),
- CtxRegs = btb_context_regs(Regs),
- case btb_are_all_unused(CtxRegs, Is, D) of
- false -> btb_error({CtxRegs,not_all_unused_after,I});
- true -> D#btb{must_not_save=true}
- end
- end;
-btb_reaches_match_2([{bs_context_to_binary,Src}=I|Is], Regs0, D) ->
- case btb_contains_context(Src, Regs0) of
- false ->
- btb_reaches_match_1(Is, Regs0, D);
- true ->
- %% Check that all other copies of the context registers
- %% are unused by the following instructions.
- Regs = btb_kill([Src], Regs0),
- CtxRegs = btb_context_regs(Regs),
- case btb_are_all_unused(CtxRegs, Is, D) of
- false -> btb_error({CtxRegs,not_all_unused_after,I});
- true -> D#btb{must_not_save=true}
- end
- end;
-btb_reaches_match_2([{badmatch,Src}=I|_], Regs, D) ->
- btb_ensure_not_used([Src], I, Regs),
- D;
-btb_reaches_match_2([{case_end,Src}=I|_], Regs, D) ->
- btb_ensure_not_used([Src], I, Regs),
- D;
-btb_reaches_match_2([if_end|_], _Regs, D) ->
- D;
-btb_reaches_match_2([{func_info,_,_,Arity}=I|_], Regs0, D) ->
- Regs = btb_kill_yregs(btb_kill_not_live(Arity, Regs0)),
- case btb_context_regs(Regs) of
- [] -> D;
- _ -> {binary_used_in,I}
- end;
-btb_reaches_match_2([{line,_}|Is], Regs, D) ->
- btb_reaches_match_1(Is, Regs, D);
-btb_reaches_match_2([I|_], Regs, _) ->
- btb_error({btb_context_regs(Regs),I,not_handled}).
-
-is_tail_call([{deallocate,_}|_]) -> true;
-is_tail_call([return|_]) -> true;
-is_tail_call(_) -> false.
-
-btb_call(Arity, Lbl, Regs0, Is, D0) ->
- Regs = btb_kill_not_live(Arity, Regs0),
- case btb_are_x_registers_empty(Regs) of
- false ->
- %% There is a match context in one of the x registers.
- %% First handle the call as if it were a tail call.
- D = btb_tail_call(Lbl, Regs, D0),
-
- %% No problem so far (the called function can handle a
- %% match context). Now we must make sure that we don't
- %% have any copies of the match context tucked away in an
- %% y register.
- RegList = btb_context_regs(Regs),
- case [R || {y,_}=R <- RegList] of
- [] ->
- D;
- [_|_] ->
- btb_error({multiple_uses,RegList})
- end;
- true ->
- %% No match context in any x register. It could have been
- %% saved to an y register, so continue to scan the code following
- %% the call.
- btb_reaches_match_1(Is, Regs, D0)
- end.
-
-btb_tail_call(Lbl, Regs, #btb{f=Ftree,must_save=MustSave0}=D) ->
- %% Ignore any y registers here.
- case [R || {x,_}=R <- btb_context_regs(Regs)] of
- [] ->
- D;
- [{x,_}=Reg] ->
- case gb_trees:lookup(Lbl, Ftree) of
- {value,{Reg,MustSave}} ->
- D#btb{must_save=MustSave0 or MustSave};
- _ when is_integer(Lbl) ->
- btb_error({{label,Lbl},no_suitable_bs_start_match});
- _ ->
- btb_error({binary_used_in,Lbl})
- end;
- [_|_] when not is_integer(Lbl) ->
- btb_error({binary_used_in,Lbl});
- [_|_]=RegList ->
- btb_error({multiple_uses,RegList})
- end.
-
-%% btb_follow_branches([Cond], Regs, D) -> D'
-%% Recursively follow all the branches.
-
-btb_follow_branches([{f,Lbl}|T], Regs, D0) ->
- D = btb_follow_branch(Lbl, Regs, D0),
- btb_follow_branches(T, Regs, D);
-btb_follow_branches([_|T], Regs, D) ->
- btb_follow_branches(T, Regs, D);
-btb_follow_branches([], _, D) -> D.
-
-%% btb_follow_branch(Lbl, Regs, D) -> D'
-%% Recursively follow the branch.
-
-btb_follow_branch(0, _Regs, D) -> D;
-btb_follow_branch(Lbl, Regs, #btb{ok_br=Br0,index=Li}=D) ->
- Key = {Lbl,Regs},
- case gb_sets:is_member(Key, Br0) of
- true ->
- %% We have already followed this branch and it was OK.
- D;
- false ->
- %% New branch. Try it.
- Is = fetch_code_at(Lbl, Li),
- #btb{ok_br=Br,must_not_save=MustNotSave,must_save=MustSave} =
- btb_reaches_match_1(Is, Regs, D),
-
- %% Since we got back, this branch is OK.
- D#btb{ok_br=gb_sets:insert(Key, Br),must_not_save=MustNotSave,
- must_save=MustSave}
- end.
-
-btb_reaches_match_block([{set,Ds,Ss,{alloc,Live,_}}=I|Is], Regs0) ->
- %% An allocation instruction or a GC bif. We'll kill all registers
- %% if any copy of the context is used as the source to the BIF.
- btb_ensure_not_used(Ss, I, Regs0),
- Regs1 = btb_kill_not_live(Live, Regs0),
- Regs = btb_kill(Ds, Regs1),
- btb_reaches_match_block(Is, Regs);
-btb_reaches_match_block([{set,[Dst]=Ds,[Src],move}|Is], Regs0) ->
- Regs1 = btb_kill(Ds, Regs0),
- Regs = case btb_contains_context(Src, Regs1) of
- false -> Regs1;
- true -> btb_set_context(Dst, Regs1)
- end,
- btb_reaches_match_block(Is, Regs);
-btb_reaches_match_block([{set,Ds,Ss,_}=I|Is], Regs0) ->
- btb_ensure_not_used(Ss, I, Regs0),
- Regs = btb_kill(Ds, Regs0),
- btb_reaches_match_block(Is, Regs);
-btb_reaches_match_block([], Regs) ->
- Regs.
-
-%% btb_are_all_killed([Register], [Instruction], D) -> true|false
-%% Test whether all of the register are unused in the instruction stream.
-
-btb_are_all_unused(RegList, Is, #btb{index=Li}) ->
- all(fun(R) ->
- beam_utils:is_not_used(R, Is, Li)
- end, RegList).
-
-%% btp_regs_from_list([Register]) -> RegisterSet.
-%% Create a register set from a list of registers.
-
-btb_regs_from_list(L) ->
- foldl(fun(R, Regs) ->
- btb_set_context(R, Regs)
- end, {0,0}, L).
-
-%% btb_set_context(Register, RegisterSet) -> RegisterSet'
-%% Update RegisterSet to indicate that Register contains the matching context.
-
-btb_set_context({x,N}, {Xregs,Yregs}) ->
- {Xregs bor (1 bsl N),Yregs};
-btb_set_context({y,N}, {Xregs,Yregs}) ->
- {Xregs,Yregs bor (1 bsl N)}.
-
-%% btb_ensure_not_used([Register], Instruction, RegisterSet) -> ok
-%% If any register in RegisterSet (the register(s) known to contain
-%% the match context) is used in the list of registers, generate an error.
-
-btb_ensure_not_used(Rs, I, Regs) ->
- case lists:any(fun(R) -> btb_contains_context(R, Regs) end, Rs) of
- true -> btb_error({binary_used_in,I});
- false -> ok
- end.
-
-%% btb_kill([Register], RegisterSet) -> RegisterSet'
-%% Kill all registers mentioned in the list of registers.
-
-btb_kill([{x,N}|Rs], {Xregs,Yregs}) ->
- btb_kill(Rs, {Xregs band (bnot (1 bsl N)),Yregs});
-btb_kill([{y,N}|Rs], {Xregs,Yregs}) ->
- btb_kill(Rs, {Xregs,Yregs band (bnot (1 bsl N))});
-btb_kill([{fr,_}|Rs], Regs) ->
- btb_kill(Rs, Regs);
-btb_kill([], Regs) -> Regs.
-
-%% btb_kill_not_live(Live, RegisterSet) -> RegisterSet'
-%% Kill all registers indicated not live by Live.
-
-btb_kill_not_live(Live, {Xregs,Yregs}) ->
- {Xregs band ((1 bsl Live)-1),Yregs}.
-
-%% btb_kill(Regs0) -> Regs
-%% Kill all y registers.
-
-btb_kill_yregs({Xregs,_}) -> {Xregs,0}.
-
-%% btb_are_registers_empty(RegisterSet) -> true|false
-%% Test whether the register set is empty.
-
-btb_are_registers_empty({0,0}) -> true;
-btb_are_registers_empty({_,_}) -> false.
-
-%% btb_are_x_registers_empty(Regs) -> true|false
-%% Test whether the x registers are empty.
-
-btb_are_x_registers_empty({0,_}) -> true;
-btb_are_x_registers_empty({_,_}) -> false.
-
-%% btb_contains_context(Register, RegisterSet) -> true|false
-%% Test whether Register contains the context.
-
-btb_contains_context({x,N}, {Regs,_}) -> Regs band (1 bsl N) =/= 0;
-btb_contains_context({y,N}, {_,Regs}) -> Regs band (1 bsl N) =/= 0;
-btb_contains_context(_, _) -> false.
-
-%% btb_context_regs(RegisterSet) -> [Register]
-%% Convert the register set to an explicit list of registers.
-btb_context_regs({Xregs,Yregs}) ->
- btb_context_regs_1(Xregs, 0, x, btb_context_regs_1(Yregs, 0, y, [])).
-
-btb_context_regs_1(0, _, _, Acc) ->
- Acc;
-btb_context_regs_1(Regs, N, Tag, Acc) when (Regs band 1) =:= 1 ->
- btb_context_regs_1(Regs bsr 1, N+1, Tag, [{Tag,N}|Acc]);
-btb_context_regs_1(Regs, N, Tag, Acc) ->
- btb_context_regs_1(Regs bsr 1, N+1, Tag, Acc).
-
-%% btb_index([Function]) -> GbTree({EntryLabel,{Register,MustSave}})
-%% Build an index of functions that accept a match context instead of
-%% a binary. MustSave is true if the function may pass the match
-%% context to the bs_context_to_binary instruction (in which case
-%% the current position in the binary must have saved into the
-%% start position using "bs_save_2 Ctx start").
-
-btb_index(Fs) ->
- btb_index_1(Fs, []).
-
-btb_index_1([{function,_,_,Entry,Is0}|Fs], Acc0) ->
- Is = drop_to_label(Is0, Entry),
- Acc = btb_index_2(Is, Entry, false, Acc0),
- btb_index_1(Fs, Acc);
-btb_index_1([], Acc) -> gb_trees:from_orddict(sort(Acc)).
-
-btb_index_2([{test,bs_start_match2,{f,_},_,[Reg,_],Reg}|_],
- Entry, MustSave, Acc) ->
- [{Entry,{Reg,MustSave}}|Acc];
-btb_index_2(Is0, Entry, _, Acc) ->
- try btb_index_find_start_match(Is0) of
- Is -> btb_index_2(Is, Entry, true, Acc)
- catch
- throw:none -> Acc
- end.
-
-drop_to_label([{label,L}|Is], L) -> Is;
-drop_to_label([_|Is], L) -> drop_to_label(Is, L).
-
-btb_index_find_start_match([{test,_,{f,F},_},{bs_context_to_binary,_}|Is]) ->
- btb_index_find_label(Is, F);
-btb_index_find_start_match(_) ->
- throw(none).
-
-btb_index_find_label([{label,L}|Is], L) -> Is;
-btb_index_find_label([_|Is], L) -> btb_index_find_label(Is, L).
-
-btb_error(Error) ->
- throw({error,Error}).
-
-fetch_code_at(Lbl, Li) ->
- case beam_utils:code_at(Lbl, Li) of
- Is when is_list(Is) -> Is
- end.
-
-%%%
-%%% Compilation information warnings.
-%%%
-
-btb_comment_opt({field_flags,[{anno,A}|_]}) ->
- {'%',{bin_opt,A}};
-btb_comment_opt(_) ->
- {'%',{bin_opt,[]}}.
-
-btb_comment_no_opt(Reason, {field_flags,[{anno,A}|_]}) ->
- {'%',{no_bin_opt,Reason,A}};
-btb_comment_no_opt(Reason, _) ->
- {'%',{no_bin_opt,Reason,[]}}.
-
-collect_warnings(Fs) ->
- D = warning_index_functions(Fs),
- foldl(fun(F, A) -> collect_warnings_fun(F, D, A) end, [], Fs).
-
-collect_warnings_fun({function,_,_,_,Is}, D, A) ->
- collect_warnings_instr(Is, D, A).
-
-collect_warnings_instr([{'%',{bin_opt,Where}}|Is], D, Acc0) ->
- Acc = add_warning(bin_opt, Where, Acc0),
- collect_warnings_instr(Is, D, Acc);
-collect_warnings_instr([{'%',{no_bin_opt,Reason0,Where}}|Is], D, Acc0) ->
- Reason = warning_translate_label(Reason0, D),
- Acc = add_warning({no_bin_opt,Reason}, Where, Acc0),
- collect_warnings_instr(Is, D, Acc);
-collect_warnings_instr([_|Is], D, Acc) ->
- collect_warnings_instr(Is, D, Acc);
-collect_warnings_instr([], _, Acc) -> Acc.
-
-add_warning(Term, Anno, Ws) ->
- Line = get_line(Anno),
- File = get_file(Anno),
- [{File,[{Line,?MODULE,Term}]}|Ws].
-
-warning_translate_label(Term, D) when is_tuple(Term) ->
- case element(1, Term) of
- {label,F} ->
- FA = gb_trees:get(F, D),
- setelement(1, Term, FA);
- _ -> Term
- end;
-warning_translate_label(Term, _) -> Term.
-
-get_line([Line|_]) when is_integer(Line) -> Line;
-get_line([_|T]) -> get_line(T);
-get_line([]) -> none.
-
-get_file([{file,File}|_]) -> File;
-get_file([_|T]) -> get_file(T);
-get_file([]) -> "no_file". % should not happen
-
-warning_index_functions(Fs) ->
- D = [{Entry,{F,A}} || {function,F,A,Entry,_} <- Fs],
- gb_trees:from_orddict(sort(D)).
-
-format_error_1({binary_used_in,{extfunc,M,F,A}}) ->
- [io_lib:format("sub binary used by ~p:~p/~p", [M,F,A])|
- case {M,F,A} of
- {erlang,split_binary,2} ->
- "; SUGGEST using binary matching instead of split_binary/2";
- _ ->
- ""
- end];
-format_error_1({binary_used_in,_}) ->
- "sub binary is used or returned";
-format_error_1({multiple_uses,_}) ->
- "sub binary is matched or used in more than one place";
-format_error_1(unsuitable_bs_start_match) ->
- "the binary matching instruction that follows in the same function "
- "have problems that prevent delayed sub binary optimization "
- "(probably indicated by INFO warnings)";
-format_error_1({{F,A},no_suitable_bs_start_match}) ->
- io_lib:format("called function ~p/~p does not begin with a suitable "
- "binary matching instruction", [F,A]);
-format_error_1(must_and_must_not_save) ->
- "different control paths use different positions in the binary";
-format_error_1({_,I,not_handled}) ->
- case I of
- {'catch',_,_} ->
- "the compiler currently does not attempt the delayed sub binary "
- "optimization when catch is used";
- {'try',_,_} ->
- "the compiler currently does not attempt the delayed sub binary "
- "optimization when try/catch is used";
- _ ->
- io_lib:format("compiler limitation: instruction ~p prevents "
- "delayed sub binary optimization", [I])
- end;
-format_error_1(Term) ->
- io_lib:format("~w", [Term]).
diff --git a/lib/compiler/src/beam_disasm.erl b/lib/compiler/src/beam_disasm.erl
index d0be39f520..7d048716e4 100644
--- a/lib/compiler/src/beam_disasm.erl
+++ b/lib/compiler/src/beam_disasm.erl
@@ -1105,6 +1105,16 @@ resolve_inst({get_hd,[Src,Dst]},_,_,_) ->
resolve_inst({get_tl,[Src,Dst]},_,_,_) ->
{get_tl,Src,Dst};
+%% OTP 22
+resolve_inst({bs_start_match3,[Fail,Bin,Live,Dst]},_,_,_) ->
+ {bs_start_match3,Fail,Bin,Live,Dst};
+resolve_inst({bs_get_tail,[Src,Dst,Live]},_,_,_) ->
+ {bs_get_tail,Src,Dst,Live};
+resolve_inst({bs_get_position,[Src,Dst,Live]},_,_,_) ->
+ {bs_get_position,Src,Dst,Live};
+resolve_inst({bs_set_position,[Src,Dst]},_,_,_) ->
+ {bs_set_position,Src,Dst};
+
%%
%% OTP 22.
%%
diff --git a/lib/compiler/src/beam_jump.erl b/lib/compiler/src/beam_jump.erl
index 6d0a8db2dc..fbff4cfd79 100644
--- a/lib/compiler/src/beam_jump.erl
+++ b/lib/compiler/src/beam_jump.erl
@@ -367,8 +367,6 @@ extract_seq([{line,_}=Line|Is], Acc) ->
extract_seq(Is, [Line|Acc]);
extract_seq([{block,_}=Bl|Is], Acc) ->
extract_seq_1(Is, [Bl|Acc]);
-extract_seq([{bs_context_to_binary,_}=I|Is], Acc) ->
- extract_seq_1(Is, [I|Acc]);
extract_seq([{label,_}|_]=Is, Acc) ->
extract_seq_1(Is, Acc);
extract_seq(_, _) -> no.
diff --git a/lib/compiler/src/beam_kernel_to_ssa.erl b/lib/compiler/src/beam_kernel_to_ssa.erl
index c55a57ab32..d6e675ae72 100644
--- a/lib/compiler/src/beam_kernel_to_ssa.erl
+++ b/lib/compiler/src/beam_kernel_to_ssa.erl
@@ -276,12 +276,11 @@ select_nil(#k_val_clause{val=#k_nil{},body=B}, V, Tf, Vf, St0) ->
{Is ++ Bis,St}.
select_binary(#k_val_clause{val=#k_binary{segs=#k_var{name=Ctx0}},body=B},
- #k_var{anno=Anno0}=Src, Tf, Vf, St0) ->
- Anno = #{reuse_for_context=>member(reuse_for_context, Anno0)},
+ #k_var{}=Src, Tf, Vf, St0) ->
{Ctx,St1} = new_ssa_var(Ctx0, St0),
{Bis0,St2} = match_cg(B, Vf, St1),
{TestIs,St} = make_cond_branch(succeeded, [Ctx], Tf, St2),
- Bis1 = [#b_set{anno=Anno,op=bs_start_match,dst=Ctx,
+ Bis1 = [#b_set{op=bs_start_match,dst=Ctx,
args=[ssa_arg(Src, St)]}] ++ TestIs ++ Bis0,
Bis = finish_bs_matching(Bis1),
{Bis,St}.
@@ -708,10 +707,6 @@ bif_cg(#k_bif{op=#k_remote{mod=#k_atom{val=erlang},name=#k_atom{val=Name}},
%% internal_cg(Bif, [Arg], [Ret], Le, State) ->
%% {[Ainstr],State}.
-internal_cg(bs_context_to_binary, [Src0], [], _Le, St) ->
- Src = ssa_arg(Src0, St),
- Set = #b_set{op=context_to_binary,args=[Src]},
- {[Set],St};
internal_cg(dsetelement, [Index0,Tuple0,New0], _Rs, _Le, St) ->
[New,Tuple,#b_literal{val=Index1}] = ssa_args([New0,Tuple0,Index0], St),
Index = #b_literal{val=Index1-1},
diff --git a/lib/compiler/src/beam_ssa.erl b/lib/compiler/src/beam_ssa.erl
index 9d10d4aec3..1a2e759965 100644
--- a/lib/compiler/src/beam_ssa.erl
+++ b/lib/compiler/src/beam_ssa.erl
@@ -20,12 +20,15 @@
%% Purpose: Type definitions and utilities for the SSA format.
-module(beam_ssa).
--export([add_anno/3,get_anno/2,
- clobbers_xregs/1,def/2,def_used/2,dominators/1,
+-export([add_anno/3,get_anno/2,get_anno/3,
+ clobbers_xregs/1,def/2,def_used/2,
+ definitions/1,
+ dominators/1,
flatmapfold_instrs_rpo/4,
fold_po/3,fold_po/4,fold_rpo/3,fold_rpo/4,
fold_instrs_rpo/4,
linearize/1,
+ mapfold_blocks_rpo/4,
mapfold_instrs_rpo/4,
normalize/1,
no_side_effect/1,
@@ -35,14 +38,17 @@
split_blocks/3,
successors/1,successors/2,
trim_unreachable/1,
- update_phi_labels/4,used/1]).
+ update_phi_labels/4,used/1,
+ uses/1,uses/2]).
-export_type([b_module/0,b_function/0,b_blk/0,b_set/0,
b_ret/0,b_br/0,b_switch/0,terminator/0,
b_var/0,b_literal/0,b_remote/0,b_local/0,
value/0,argument/0,label/0,
var_name/0,var_base/0,literal_value/0,
- op/0,anno/0,block_map/0]).
+ op/0,anno/0,block_map/0,dominator_map/0,
+ rename_map/0,rename_proplist/0,usage_map/0,
+ definition_map/0]).
-include("beam_ssa.hrl").
@@ -56,6 +62,9 @@
-type b_switch() :: #b_switch{}.
-type terminator() :: b_br() | b_ret() | b_switch().
+-type construct() :: b_module() | b_function() | b_blk() | b_set() |
+ terminator().
+
-type b_var() :: #b_var{}.
-type b_literal() :: #b_literal{}.
-type b_remote() :: #b_remote{}.
@@ -76,6 +85,11 @@
-type anno() :: #{atom() := any()}.
-type block_map() :: #{label():=b_blk()}.
+-type dominator_map() :: #{label():=ordsets:ordset(label())}.
+-type usage_map() :: #{b_var():=[{label(),b_set() | terminator()}]}.
+-type definition_map() :: #{b_var():=b_set()}.
+-type rename_map() :: #{b_var():=value()}.
+-type rename_proplist() :: [{b_var(),value()}].
%% Note: By default, dialyzer will collapse this type to atom().
%% To avoid the collapsing, change the value of SET_LIMIT to 50 in the
@@ -84,7 +98,7 @@
-type prim_op() :: 'bs_add' | 'bs_extract' | 'bs_init' | 'bs_init_writable' |
'bs_match' | 'bs_put' | 'bs_start_match' | 'bs_test_tail' |
'bs_utf16_size' | 'bs_utf8_size' | 'build_stacktrace' |
- 'call' | 'catch_end' | 'context_to_binary' |
+ 'call' | 'catch_end' |
'extract' |
'get_hd' | 'get_map_element' | 'get_tl' | 'get_tuple_element' |
'has_map_field' |
@@ -103,14 +117,14 @@
%% Primops only used internally during code generation.
-type cg_prim_op() :: 'bs_get' | 'bs_match_string' | 'bs_restore' | 'bs_skip' |
-'copy' | 'put_tuple_arity' | 'put_tuple_element'.
+ 'copy' | 'put_tuple_arity' | 'put_tuple_element'.
-import(lists, [foldl/3,keyfind/3,mapfoldl/3,member/2,reverse/1]).
-spec add_anno(Key, Value, Construct) -> Construct when
Key :: atom(),
Value :: any(),
- Construct :: b_function() | b_blk() | b_set() | terminator().
+ Construct :: construct().
add_anno(Key, Val, #b_function{anno=Anno}=Bl) ->
Bl#b_function{anno=Anno#{Key=>Val}};
@@ -125,11 +139,17 @@ add_anno(Key, Val, #b_ret{anno=Anno}=Bl) ->
add_anno(Key, Val, #b_switch{anno=Anno}=Bl) ->
Bl#b_switch{anno=Anno#{Key=>Val}}.
--spec get_anno(atom(), b_blk()|b_set()|terminator()) -> any().
+-spec get_anno(atom(), construct()) -> any().
get_anno(Key, Construct) ->
maps:get(Key, get_anno(Construct)).
+-spec get_anno(atom(), construct(),any()) -> any().
+
+get_anno(Key, Construct, Default) ->
+ maps:get(Key, get_anno(Construct), Default).
+
+get_anno(#b_function{anno=Anno}) -> Anno;
get_anno(#b_blk{anno=Anno}) -> Anno;
get_anno(#b_set{anno=Anno}) -> Anno;
get_anno(#b_br{anno=Anno}) -> Anno;
@@ -169,6 +189,7 @@ no_side_effect(#b_set{op=Op}) ->
bs_match -> true;
bs_start_match -> true;
bs_test_tail -> true;
+ bs_get_tail -> true;
bs_put -> true;
extract -> true;
get_hd -> true;
@@ -306,7 +327,7 @@ def_used(Ls, Blocks) ->
-spec dominators(Blocks) -> Result when
Blocks :: block_map(),
- Result :: #{label():=ordsets:ordset(label())}.
+ Result :: dominator_map().
dominators(Blocks) ->
Preds = predecessors(Blocks),
@@ -327,6 +348,26 @@ fold_instrs_rpo(Fun, From, Acc0, Blocks) ->
Top = rpo(From, Blocks),
fold_instrs_rpo_1(Top, Fun, Blocks, Acc0).
+%% Like mapfold_instrs_rpo but at the block level to support lookahead and
+%% scope-dependent transformations.
+-spec mapfold_blocks_rpo(Fun, From, Acc, Blocks) -> Result when
+ Fun :: fun((label(), b_blk(), any()) -> {b_blk(), any()}),
+ From :: [label()],
+ Acc :: any(),
+ Blocks :: block_map(),
+ Result :: {block_map(), any()}.
+mapfold_blocks_rpo(Fun, From, Acc, Blocks) ->
+ Successors = rpo(From, Blocks),
+ foldl(fun(Lbl, A) ->
+ mapfold_blocks_rpo_1(Fun, Lbl, A)
+ end, {Blocks, Acc}, Successors).
+
+mapfold_blocks_rpo_1(Fun, Lbl, {Blocks0, Acc0}) ->
+ Block0 = maps:get(Lbl, Blocks0),
+ {Block, Acc} = Fun(Lbl, Block0, Acc0),
+ Blocks = maps:put(Lbl, Block, Blocks0),
+ {Blocks, Acc}.
+
-spec mapfold_instrs_rpo(Fun, From, Acc0, Blocks0) -> {Blocks,Acc} when
Fun :: fun((b_blk()|terminator(), any()) -> any()),
From :: [label()],
@@ -442,7 +483,7 @@ rpo(From, Blocks) ->
Ls.
-spec rename_vars(Rename, [label()], block_map()) -> block_map() when
- Rename :: [{var_name(),value()}] | #{var_name():=value()}.
+ Rename :: rename_map() | rename_proplist().
rename_vars(Rename, From, Blocks) when is_list(Rename) ->
rename_vars(maps:from_list(Rename), From, Blocks);
@@ -535,6 +576,34 @@ used(#b_switch{arg=#b_var{}=V}) ->
[V];
used(_) -> [].
+-spec definitions(Blocks :: block_map()) -> definition_map().
+definitions(Blocks) ->
+ beam_ssa:fold_instrs_rpo(fun(#b_set{ dst = Var }=I, Acc) ->
+ maps:put(Var, I, Acc);
+ (_Terminator, Acc) ->
+ Acc
+ end, [0], #{}, Blocks).
+
+-spec uses(Blocks :: block_map()) -> usage_map().
+uses(Blocks) ->
+ uses([0], Blocks).
+
+-spec uses(From, Blocks) -> usage_map() when
+ From :: [label()],
+ Blocks :: block_map().
+uses(From, Blocks) ->
+ beam_ssa:fold_rpo(fun fold_uses_block/3, From, #{}, Blocks).
+
+fold_uses_block(Lbl, #b_blk{is=Is,last=Last}, UseMap0) ->
+ F = fun(I, UseMap) ->
+ foldl(fun(Var, Acc) ->
+ Uses0 = maps:get(Var, Acc, []),
+ Uses = [{Lbl, I} | Uses0],
+ maps:put(Var, Uses, Acc)
+ end, UseMap, beam_ssa:used(I))
+ end,
+ F(Last, foldl(F, UseMap0, Is)).
+
%%%
%%% Internal functions.
%%%
diff --git a/lib/compiler/src/beam_ssa_bsm.erl b/lib/compiler/src/beam_ssa_bsm.erl
new file mode 100644
index 0000000000..2efeb6b5b6
--- /dev/null
+++ b/lib/compiler/src/beam_ssa_bsm.erl
@@ -0,0 +1,1027 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2018. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%% http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+
+%%%
+%%% This pass optimizes bit syntax matching, and is centered around the concept
+%%% of "match context reuse" which is best explained through example. To put it
+%%% shortly we attempt to turn this:
+%%%
+%%% <<0,B/bits>> = A,
+%%% <<1,C/bits>> = B,
+%%% <<D,_/bits>> = C,
+%%% D.
+%%%
+%%% ... Into this:
+%%%
+%%% <<0,1,D,_/bits>>=A,
+%%% D.
+%%%
+%%% Which is much faster as it avoids the creation of intermediate terms. This
+%%% is especially noticeable in loops where such garbage is generated on each
+%%% iteration.
+%%%
+%%% The optimization itself is very simple and can be applied whenever there's
+%%% matching on the tail end of a binary; instead of creating a new binary and
+%%% starting a new match context on it, we reuse the match context used to
+%%% extract the tail and avoid the creation of both objects.
+%%%
+%%% The catch is that a match context isn't a proper type and nothing outside
+%%% of bit syntax match operations can handle them. We therefore need to make
+%%% sure that they never "leak" into other instructions, and most of the pass
+%%% revolves around getting around that limitation.
+%%%
+%%% Unlike most other passes we look at the whole module so we can combine
+%%% matches across function boundaries, greatly increasing the performance of
+%%% complex matches and loops.
+%%%
+
+-module(beam_ssa_bsm).
+
+-export([module/2, format_error/1]).
+
+-include("beam_ssa.hrl").
+
+-import(lists, [member/2, reverse/1, splitwith/2, map/2, foldl/3, mapfoldl/3,
+ nth/2, max/1, unzip/1]).
+
+-spec format_error(term()) -> nonempty_string().
+
+format_error(OptInfo) ->
+ format_opt_info(OptInfo).
+
+-spec module(Module, Options) -> Result when
+ Module :: beam_ssa:b_module(),
+ Options :: [compile:option()],
+ Result :: {ok, beam_ssa:b_module(), list()}.
+
+-define(PASS(N), {N,fun N/1}).
+
+module(#b_module{body=Fs0}=Module, Opts) ->
+ ModInfo = analyze_module(Module),
+
+ %% combine_matches is repeated after accept_context_args as the control
+ %% flow changes can enable further optimizations, as in the example below:
+ %%
+ %% a(<<0,X/binary>>) -> a(X);
+ %% a(A) when bit_size(A) =:= 52 -> bar;
+ %% a(<<1,X/binary>>) -> X. %% Match context will be reused here when
+ %% %% when repeated.
+
+ {Fs, _} = compile:run_sub_passes(
+ [?PASS(combine_matches),
+ ?PASS(accept_context_args),
+ ?PASS(combine_matches),
+ ?PASS(allow_context_passthrough),
+ ?PASS(skip_outgoing_tail_extraction),
+ ?PASS(annotate_context_parameters)],
+ {Fs0, ModInfo}),
+
+ Ws = case proplists:get_bool(bin_opt_info, Opts) of
+ true -> collect_opt_info(Fs);
+ false -> []
+ end,
+
+ {ok, Module#b_module{body=Fs}, Ws}.
+
+-type module_info() :: #{ func_id() => func_info() }.
+
+-type func_id() :: {Name :: atom(), Arity :: non_neg_integer()}.
+
+-type func_info() :: #{ has_bsm_ops => boolean(),
+ parameters => [#b_var{}],
+ parameter_info => #{ #b_var{} => param_info() } }.
+
+-type param_info() :: suitable_for_reuse |
+ {Problem :: atom(), Where :: term()}.
+
+-spec analyze_module(#b_module{}) -> module_info().
+
+analyze_module(#b_module{body=Fs}) ->
+ foldl(fun(#b_function{args=Parameters}=F, I) ->
+ FuncInfo = #{ has_bsm_ops => has_bsm_ops(F),
+ parameters => Parameters,
+ parameter_info => #{} },
+ FuncId = get_fa(F),
+ I#{ FuncId => FuncInfo }
+ end, #{}, Fs).
+
+has_bsm_ops(#b_function{bs=Blocks}) ->
+ hbo_blocks(maps:to_list(Blocks)).
+
+hbo_blocks([{_,#b_blk{is=Is}} | Blocks]) ->
+ case hbo_is(Is) of
+ false -> hbo_blocks(Blocks);
+ true -> true
+ end;
+hbo_blocks([]) ->
+ false.
+
+hbo_is([#b_set{op=bs_start_match} | _]) -> true;
+hbo_is([_I | Is]) -> hbo_is(Is);
+hbo_is([]) -> false.
+
+%% Checks whether it's legal to make a call with the given argument as a match
+%% context, returning the param_info() of the relevant parameter.
+-spec check_context_call(#b_set{}, Arg, CtxChain, ModInfo) -> param_info() when
+ Arg :: #b_var{},
+ CtxChain :: [#b_var{}],
+ ModInfo :: module_info().
+check_context_call(#b_set{args=Args}, Arg, CtxChain, ModInfo) ->
+ Aliases = [Arg | CtxChain],
+ ccc_1(Args, Arg, Aliases, ModInfo).
+
+ccc_1([#b_local{}=Call | Args], Ctx, Aliases, ModInfo) ->
+ %% Matching operations assume that their context isn't aliased (as in
+ %% pointer aliasing), so we must reject calls whose arguments contain more
+ %% than one reference to the context.
+ %%
+ %% TODO: Try to fall back to passing binaries in these cases. Partial reuse
+ %% is better than nothing.
+ UseCount = foldl(fun(Arg, C) ->
+ case member(Arg, Aliases) of
+ true -> C + 1;
+ false -> C
+ end
+ end, 0, Args),
+ if
+ UseCount =:= 1 ->
+ #b_local{name=#b_literal{val=Name},arity=Arity} = Call,
+ Callee = {Name, Arity},
+
+ ParamInfo = funcinfo_get(Callee, parameter_info, ModInfo),
+ Parameters = funcinfo_get(Callee, parameters, ModInfo),
+ Parameter = nth(1 + arg_index(Ctx, Args), Parameters),
+
+ case maps:find(Parameter, ParamInfo) of
+ {ok, suitable_for_reuse} ->
+ suitable_for_reuse;
+ {ok, Other} ->
+ {unsuitable_call, {Call, Other}};
+ error ->
+ {no_match_on_entry, Call}
+ end;
+ UseCount > 1 ->
+ {multiple_uses_in_call, Call}
+ end;
+ccc_1([#b_remote{}=Call | _Args], _Ctx, _CtxChain, _ModInfo) ->
+ {remote_call, Call};
+ccc_1([Fun | _Args], _Ctx, _CtxChain, _ModInfo) ->
+ %% TODO: It may be possible to support this in the future for locally
+ %% defined funs, including ones with free variables.
+ {fun_call, Fun}.
+
+%% Returns the index of Var in Args.
+arg_index(Var, Args) -> arg_index_1(Var, Args, 0).
+
+arg_index_1(Var, [Var | _Args], Index) -> Index;
+arg_index_1(Var, [_Arg | Args], Index) -> arg_index_1(Var, Args, Index + 1).
+
+is_tail_binary(#b_set{op=bs_match,args=[#b_literal{val=binary} | Rest]}) ->
+ member(#b_literal{val=all}, Rest);
+is_tail_binary(#b_set{op=bs_get_tail}) ->
+ true;
+is_tail_binary(_) ->
+ false.
+
+is_tail_binary(#b_var{}=Var, Defs) ->
+ case find_match_definition(Var, Defs) of
+ {ok, Def} -> is_tail_binary(Def);
+ _ -> false
+ end;
+is_tail_binary(_Literal, _Defs) ->
+ false.
+
+assert_match_context(#b_var{}=Var, Defs) ->
+ case maps:find(Var, Defs) of
+ {ok, #b_set{op=bs_match,args=[_,#b_var{}=Ctx|_]}} ->
+ assert_match_context(Ctx, Defs);
+ {ok, #b_set{op=bs_start_match}} ->
+ ok
+ end.
+
+find_match_definition(#b_var{}=Var, Defs) ->
+ case maps:find(Var, Defs) of
+ {ok, #b_set{op=bs_extract,args=[Ctx]}} -> maps:find(Ctx, Defs);
+ {ok, #b_set{op=bs_get_tail}=Def} -> {ok, Def};
+ _ -> error
+ end.
+
+%% Returns a list of all contexts that were used to extract Var.
+context_chain_of(#b_var{}=Var, Defs) ->
+ case maps:find(Var, Defs) of
+ {ok, #b_set{op=bs_match,args=[_,#b_var{}=Ctx|_]}} ->
+ [Ctx | context_chain_of(Ctx, Defs)];
+ {ok, #b_set{op=bs_get_tail,args=[Ctx]}} ->
+ [Ctx | context_chain_of(Ctx, Defs)];
+ {ok, #b_set{op=bs_extract,args=[Ctx]}} ->
+ [Ctx | context_chain_of(Ctx, Defs)];
+ _ ->
+ []
+ end.
+
+%% Grabs the match context used to produce the given variable.
+match_context_of(#b_var{}=Var, Defs) ->
+ Ctx = match_context_of_1(Var, Defs),
+ assert_match_context(Ctx, Defs),
+ Ctx.
+
+match_context_of_1(Var, Defs) ->
+ case maps:get(Var, Defs) of
+ #b_set{op=bs_extract,args=[#b_var{}=Ctx0]} ->
+ #b_set{op=bs_match,
+ args=[_,#b_var{}=Ctx|_]} = maps:get(Ctx0, Defs),
+ Ctx;
+ #b_set{op=bs_get_tail,args=[#b_var{}=Ctx]} ->
+ Ctx
+ end.
+
+funcinfo_get(#b_function{}=F, Attribute, ModInfo) ->
+ funcinfo_get(get_fa(F), Attribute, ModInfo);
+funcinfo_get({_,_}=Key, Attribute, ModInfo) ->
+ FuncInfo = maps:get(Key, ModInfo),
+ maps:get(Attribute, FuncInfo).
+
+funcinfo_set(#b_function{}=F, Attribute, Value, ModInfo) ->
+ funcinfo_set(get_fa(F), Attribute, Value, ModInfo);
+funcinfo_set(Key, Attribute, Value, ModInfo) ->
+ FuncInfo = maps:put(Attribute, Value, maps:get(Key, ModInfo, #{})),
+ maps:put(Key, FuncInfo, ModInfo).
+
+get_fa(#b_function{ anno = Anno }) ->
+ {_,Name,Arity} = maps:get(func_info, Anno),
+ {Name,Arity}.
+
+%% Replaces matched-out binaries with aliases that are lazily converted to
+%% binary form when used, allowing us to keep the "match path" free of binary
+%% creation.
+
+-spec alias_matched_binaries(Blocks, Counter, AliasMap) -> Result when
+ Blocks :: beam_ssa:block_map(),
+ Counter :: non_neg_integer(),
+ AliasMap :: match_alias_map(),
+ Result :: {Blocks, Counter}.
+
+-type match_alias_map() ::
+ #{ Binary :: #b_var{} =>
+ { %% Replace all uses of Binary with an alias after this
+ %% label.
+ AliasAfter :: beam_ssa:label(),
+ %% The match context whose tail is equal to Binary.
+ Context :: #b_var{} } }.
+
+%% Keeps track of the promotions we need to insert. They're partially keyed by
+%% location because they may not be valid on all execution paths and we may
+%% need to add redundant promotions in some cases.
+-type promotion_map() ::
+ #{ { PromoteAt :: beam_ssa:label(),
+ Variable :: #b_var{} } =>
+ Instruction :: #b_set{} }.
+
+-record(amb, { dominators :: beam_ssa:dominator_map(),
+ match_aliases :: match_alias_map(),
+ cnt :: non_neg_integer(),
+ promotions = #{} :: promotion_map() }).
+
+alias_matched_binaries(Blocks0, Counter, AliasMap) when AliasMap =/= #{} ->
+ State0 = #amb{ dominators = beam_ssa:dominators(Blocks0),
+ match_aliases = AliasMap,
+ cnt = Counter },
+ {Blocks, State} = beam_ssa:mapfold_blocks_rpo(fun amb_1/3, [0], State0,
+ Blocks0),
+ {amb_insert_promotions(Blocks, State), State#amb.cnt};
+alias_matched_binaries(Blocks, Counter, _AliasMap) ->
+ {Blocks, Counter}.
+
+amb_1(Lbl, #b_blk{is=Is0,last=Last0}=Block, State0) ->
+ {Is, State1} = mapfoldl(fun(I, State) ->
+ amb_assign_set(I, Lbl, State)
+ end, State0, Is0),
+ {Last, State} = amb_assign_last(Last0, Lbl, State1),
+ {Block#b_blk{is=Is,last=Last}, State}.
+
+amb_assign_set(#b_set{op=phi,args=Args0}=I, _Lbl, State0) ->
+ %% Phi node aliases are relative to their source block, not their
+ %% containing block.
+ {Args, State} =
+ mapfoldl(fun({Arg0, Lbl}, Acc) ->
+ {Arg, State} = amb_get_alias(Arg0, Lbl, Acc),
+ {{Arg, Lbl}, State}
+ end, State0, Args0),
+ {I#b_set{args=Args}, State};
+amb_assign_set(#b_set{args=Args0}=I, Lbl, State0) ->
+ {Args, State} = mapfoldl(fun(Arg0, Acc) ->
+ amb_get_alias(Arg0, Lbl, Acc)
+ end, State0, Args0),
+ {I#b_set{args=Args}, State}.
+
+amb_assign_last(#b_ret{arg=Arg0}=T, Lbl, State0) ->
+ {Arg, State} = amb_get_alias(Arg0, Lbl, State0),
+ {T#b_ret{arg=Arg}, State};
+amb_assign_last(#b_switch{arg=Arg0}=T, Lbl, State0) ->
+ {Arg, State} = amb_get_alias(Arg0, Lbl, State0),
+ {T#b_switch{arg=Arg}, State};
+amb_assign_last(#b_br{bool=Arg0}=T, Lbl, State0) ->
+ {Arg, State} = amb_get_alias(Arg0, Lbl, State0),
+ {T#b_br{bool=Arg}, State}.
+
+amb_get_alias(#b_var{}=Arg, Lbl, State) ->
+ case maps:find(Arg, State#amb.match_aliases) of
+ {ok, {AliasAfter, Context}} ->
+ %% Our context may not have been created yet, so we skip assigning
+ %% an alias unless the given block is among our dominators.
+ Dominators = maps:get(Lbl, State#amb.dominators),
+ case ordsets:is_element(AliasAfter, Dominators) of
+ true -> amb_create_alias(Arg, Context, Lbl, State);
+ false -> {Arg, State}
+ end;
+ error ->
+ {Arg, State}
+ end;
+amb_get_alias(Arg, _Lbl, State) ->
+ {Arg, State}.
+
+amb_create_alias(#b_var{}=Arg0, Context, Lbl, State0) ->
+ Dominators = maps:get(Lbl, State0#amb.dominators),
+ Promotions0 = State0#amb.promotions,
+
+ PrevPromotions =
+ [maps:get({Dom, Arg0}, Promotions0)
+ || Dom <- Dominators, is_map_key({Dom, Arg0}, Promotions0)],
+
+ case PrevPromotions of
+ [_|_] ->
+ %% We've already created an alias prior to this block, so we'll
+ %% grab the most recent one to minimize stack use.
+
+ #b_set{dst=Alias} = max(PrevPromotions),
+ {Alias, State0};
+ [] ->
+ %% If we haven't created an alias we need to do so now. The
+ %% promotion will be inserted later by amb_insert_promotions/2.
+
+ Counter = State0#amb.cnt,
+ Alias = #b_var{name={'@ssa_bsm_alias', Counter}},
+ Promotion = #b_set{op=bs_get_tail,dst=Alias,args=[Context]},
+
+ Promotions = maps:put({Lbl, Arg0}, Promotion, Promotions0),
+ State = State0#amb{ promotions=Promotions, cnt=Counter+1 },
+
+ {Alias, State}
+ end.
+
+amb_insert_promotions(Blocks0, State) ->
+ F = fun({Lbl, #b_var{}}, Promotion, Blocks) ->
+ Block = maps:get(Lbl, Blocks),
+
+ Alias = Promotion#b_set.dst,
+ {Before, After} = splitwith(fun(#b_set{args=Args}) ->
+ not member(Alias, Args)
+ end, Block#b_blk.is),
+ Is = Before ++ [Promotion | After],
+
+ maps:put(Lbl, Block#b_blk{is=Is}, Blocks)
+ end,
+ maps:fold(F, Blocks0, State#amb.promotions).
+
+%%%
+%%% Subpasses
+%%%
+
+%% Removes superflous chained bs_start_match instructions in the same
+%% function. When matching on an extracted tail binary, or on a binary we've
+%% already matched on, we reuse the original match context.
+%%
+%% This pass runs first since it makes subsequent optimizations more effective
+%% by removing spots where promotion would be required.
+
+-type prior_match_map() ::
+ #{ Binary :: #b_var{} =>
+ [{ %% The context and success label of a previous
+ %% bs_start_match made on this binary.
+ ValidAfter :: beam_ssa:label(),
+ Context :: #b_var{} }] }.
+
+-record(cm, { definitions :: beam_ssa:definition_map(),
+ dominators :: beam_ssa:dominator_map(),
+ blocks :: beam_ssa:block_map(),
+ match_aliases = #{} :: match_alias_map(),
+ prior_matches = #{} :: prior_match_map(),
+ renames = #{} :: beam_ssa:rename_map() }).
+
+combine_matches({Fs0, ModInfo}) ->
+ Fs = map(fun(F) -> combine_matches(F, ModInfo) end, Fs0),
+ {Fs, ModInfo}.
+
+combine_matches(#b_function{bs=Blocks0,cnt=Counter0}=F, ModInfo) ->
+ case funcinfo_get(F, has_bsm_ops, ModInfo) of
+ true ->
+ {Blocks1, State} =
+ beam_ssa:mapfold_blocks_rpo(
+ fun(Lbl, #b_blk{is=Is0}=Block0, State0) ->
+ {Is, State} = cm_1(Is0, [], Lbl, State0),
+ {Block0#b_blk{is=Is}, State}
+ end, [0],
+ #cm{ definitions = beam_ssa:definitions(Blocks0),
+ dominators = beam_ssa:dominators(Blocks0),
+ blocks = Blocks0 },
+ Blocks0),
+
+ Blocks2 = beam_ssa:rename_vars(State#cm.renames, [0], Blocks1),
+
+ {Blocks, Counter} = alias_matched_binaries(Blocks2, Counter0,
+ State#cm.match_aliases),
+
+ F#b_function{ bs=Blocks, cnt=Counter };
+ false ->
+ F
+ end.
+
+cm_1([#b_set{ op=bs_start_match,
+ dst=Ctx,
+ args=[Src] },
+ #b_set{ op=succeeded,
+ dst=Bool,
+ args=[Ctx] }]=MatchSeq, Acc0, Lbl, State0) ->
+ Acc = reverse(Acc0),
+ case is_tail_binary(Src, State0#cm.definitions) of
+ true -> cm_combine_tail(Src, Ctx, Bool, Acc, State0);
+ false -> cm_handle_priors(Src, Ctx, Bool, Acc, MatchSeq, Lbl, State0)
+ end;
+cm_1([I | Is], Acc, Lbl, State) ->
+ cm_1(Is, [I | Acc], Lbl, State);
+cm_1([], Acc, _Lbl, State) ->
+ {reverse(Acc), State}.
+
+%% If we're dominated by at least one match on the same source, we can reuse
+%% the context created by that match.
+cm_handle_priors(Src, DstCtx, Bool, Acc, MatchSeq, Lbl, State0) ->
+ PriorCtxs = case maps:find(Src, State0#cm.prior_matches) of
+ {ok, Priors} ->
+ %% We've seen other match contexts on this source, but
+ %% we can only consider the ones whose success path
+ %% dominate us.
+ Dominators = maps:get(Lbl, State0#cm.dominators, []),
+ [Ctx || {ValidAfter, Ctx} <- Priors,
+ ordsets:is_element(ValidAfter, Dominators)];
+ error ->
+ []
+ end,
+ case PriorCtxs of
+ [Ctx|_] ->
+ Renames0 = State0#cm.renames,
+ Renames = Renames0#{ Bool => #b_literal{val=true}, DstCtx => Ctx },
+ {Acc, State0#cm{ renames = Renames }};
+ [] ->
+ %% Since we lack a prior match, we need to register this one in
+ %% case we dominate another.
+ State = cm_register_prior(Src, DstCtx, Lbl, State0),
+ {Acc ++ MatchSeq, State}
+ end.
+
+cm_register_prior(Src, DstCtx, Lbl, State) ->
+ Block = maps:get(Lbl, State#cm.blocks),
+ #b_br{succ=ValidAfter} = Block#b_blk.last,
+
+ Priors0 = maps:get(Src, State#cm.prior_matches, []),
+ Priors = [{ValidAfter, DstCtx} | Priors0],
+
+ PriorMatches = maps:put(Src, Priors, State#cm.prior_matches),
+ State#cm{ prior_matches = PriorMatches }.
+
+cm_combine_tail(Src, DstCtx, Bool, Acc, State0) ->
+ SrcCtx = match_context_of(Src, State0#cm.definitions),
+
+ %% We replace the source with a context alias as it normally won't be used
+ %% on the happy path after being matched, and the added cost of conversion
+ %% is negligible if it is.
+ Aliases = maps:put(Src, {0, SrcCtx}, State0#cm.match_aliases),
+
+ Renames0 = State0#cm.renames,
+ Renames = Renames0#{ Bool => #b_literal{val=true}, DstCtx => SrcCtx },
+
+ State = State0#cm{ match_aliases = Aliases, renames = Renames },
+
+ {Acc, State}.
+
+%% Lets functions accept match contexts as arguments. The parameter must be
+%% unused before the bs_start_match instruction, and it must be matched in the
+%% first block.
+
+-record(aca, { unused_parameters :: ordsets:ordset(#b_var{}),
+ counter :: non_neg_integer(),
+ parameter_info = #{} :: #{ #b_var{} => param_info() },
+ match_aliases = #{} :: match_alias_map() }).
+
+accept_context_args({Fs, ModInfo}) ->
+ mapfoldl(fun accept_context_args/2, ModInfo, Fs).
+
+accept_context_args(#b_function{bs=Blocks0}=F, ModInfo0) ->
+ case funcinfo_get(F, has_bsm_ops, ModInfo0) of
+ true ->
+ Parameters = ordsets:from_list(funcinfo_get(F, parameters, ModInfo0)),
+ State0 = #aca{ unused_parameters = Parameters,
+ counter = F#b_function.cnt },
+
+ {Blocks1, State} = aca_1(Blocks0, State0),
+ {Blocks, Counter} = alias_matched_binaries(Blocks1,
+ State#aca.counter,
+ State#aca.match_aliases),
+
+ ModInfo = funcinfo_set(F, parameter_info, State#aca.parameter_info,
+ ModInfo0),
+
+ {F#b_function{bs=Blocks,cnt=Counter}, ModInfo};
+ false ->
+ {F, ModInfo0}
+ end.
+
+aca_1(Blocks, State) ->
+ %% We only handle block 0 as we don't yet support starting a match after a
+ %% test. This is generally good enough as the sys_core_bsm pass makes the
+ %% match instruction come first if possible, and it's rare for a function
+ %% to binary-match several parameters at once.
+ EntryBlock = maps:get(0, Blocks),
+ aca_enable_reuse(EntryBlock#b_blk.is, EntryBlock, Blocks, [], State).
+
+aca_enable_reuse([#b_set{op=bs_start_match,args=[Src]}=I0 | Rest],
+ EntryBlock, Blocks0, Acc, State0) ->
+ case aca_is_reuse_safe(Src, State0) of
+ true ->
+ {I, Last, Blocks1, State} =
+ aca_reuse_context(I0, EntryBlock, Blocks0, State0),
+
+ Is = reverse([I|Acc]) ++ Rest,
+ Blocks = maps:put(0, EntryBlock#b_blk{is=Is,last=Last}, Blocks1),
+
+ {Blocks, State};
+ false ->
+ {Blocks0, State0}
+ end;
+aca_enable_reuse([I | Is], EntryBlock, Blocks, Acc, State0) ->
+ UnusedParams0 = State0#aca.unused_parameters,
+ case ordsets:intersection(UnusedParams0, beam_ssa:used(I)) of
+ [] ->
+ aca_enable_reuse(Is, EntryBlock, Blocks, [I | Acc], State0);
+ PrematureUses ->
+ UnusedParams = ordsets:subtract(UnusedParams0, PrematureUses),
+
+ %% Mark the offending parameters as unsuitable for context reuse.
+ ParamInfo = foldl(fun(A, Ps) ->
+ maps:put(A, {used_before_match, I}, Ps)
+ end, State0#aca.parameter_info, PrematureUses),
+
+ State = State0#aca{ unused_parameters = UnusedParams,
+ parameter_info = ParamInfo },
+ aca_enable_reuse(Is, EntryBlock, Blocks, [I | Acc], State)
+ end;
+aca_enable_reuse([], _EntryBlock, Blocks, _Acc, State) ->
+ {Blocks, State}.
+
+aca_is_reuse_safe(Src, State) ->
+ %% Context reuse is unsafe unless all uses are dominated by the start_match
+ %% instruction. Since we only process block 0 it's enough to check if
+ %% they're unused so far.
+ ordsets:is_element(Src, State#aca.unused_parameters).
+
+aca_reuse_context(#b_set{dst=Dst, args=[Src]}=I0, Block, Blocks0, State0) ->
+ %% When matching fails on a reused context it needs to be converted back
+ %% to a binary. We only need to do this on the success path since it can't
+ %% be a context on the type failure path, but it's very common for these
+ %% to converge which requires special handling.
+ {State1, Last, Blocks} =
+ aca_handle_convergence(Src, State0, Block#b_blk.last, Blocks0),
+
+ Aliases = maps:put(Src, {Last#b_br.succ, Dst}, State1#aca.match_aliases),
+ ParamInfo = maps:put(Src, suitable_for_reuse, State1#aca.parameter_info),
+
+ State = State1#aca{ match_aliases = Aliases,
+ parameter_info = ParamInfo },
+
+ I = beam_ssa:add_anno(accepts_match_contexts, true, I0),
+
+ {I, Last, Blocks, State}.
+
+aca_handle_convergence(Src, State0, Last0, Blocks0) ->
+ #b_br{fail=Fail0,succ=Succ0} = Last0,
+
+ SuccPath = beam_ssa:rpo([Succ0], Blocks0),
+ FailPath = beam_ssa:rpo([Fail0], Blocks0),
+
+ %% The promotion logic in alias_matched_binaries breaks down if the source
+ %% is used after the fail/success paths converge, as we have no way to tell
+ %% whether the source is a match context or something else past that point.
+ %%
+ %% We could handle this through clever insertion of phi nodes but it's
+ %% far simpler to copy either branch in its entirety. It doesn't matter
+ %% which one as long as they become disjoint.
+ ConvergedPaths = ordsets:intersection(
+ ordsets:from_list(SuccPath),
+ ordsets:from_list(FailPath)),
+
+ case maps:is_key(Src, beam_ssa:uses(ConvergedPaths, Blocks0)) of
+ true ->
+ case shortest(SuccPath, FailPath) of
+ left ->
+ {Succ, Blocks, Counter} =
+ aca_copy_successors(Succ0, Blocks0, State0#aca.counter),
+ State = State0#aca{ counter = Counter },
+ {State, Last0#b_br{succ=Succ}, Blocks};
+ right ->
+ {Fail, Blocks, Counter} =
+ aca_copy_successors(Fail0, Blocks0, State0#aca.counter),
+ State = State0#aca{ counter = Counter },
+ {State, Last0#b_br{fail=Fail}, Blocks}
+ end;
+ false ->
+ {State0, Last0, Blocks0}
+ end.
+
+shortest([_|As], [_|Bs]) -> shortest(As, Bs);
+shortest([], _) -> left;
+shortest(_, []) -> right.
+
+%% Copies all successor blocks of Lbl, returning the label to the entry block
+%% of this copy. Since the copied blocks aren't referenced anywhere else, they
+%% are all guaranteed to be dominated by Lbl.
+aca_copy_successors(Lbl0, Blocks0, Counter0) ->
+ %% Building the block rename map up front greatly simplifies phi node
+ %% handling.
+ Path = beam_ssa:rpo([Lbl0], Blocks0),
+ {BRs, Counter1} = aca_cs_build_brs(Path, Counter0, #{}),
+ {Blocks, Counter} = aca_cs_1(Path, Blocks0, Counter1, #{}, BRs, #{}),
+ Lbl = maps:get(Lbl0, BRs),
+ {Lbl, Blocks, Counter}.
+
+aca_cs_build_brs([Lbl | Path], Counter0, Acc) ->
+ aca_cs_build_brs(Path, Counter0 + 1, maps:put(Lbl, Counter0, Acc));
+aca_cs_build_brs([], Counter, Acc) ->
+ {Acc, Counter}.
+
+aca_cs_1([Lbl0 | Path], Blocks, Counter0, VRs0, BRs, Acc0) ->
+ Block0 = maps:get(Lbl0, Blocks),
+ Lbl = maps:get(Lbl0, BRs),
+ {VRs, Block, Counter} = aca_cs_block(Block0, Counter0, VRs0, BRs),
+ Acc = maps:put(Lbl, Block, Acc0),
+ aca_cs_1(Path, Blocks, Counter, VRs, BRs, Acc);
+aca_cs_1([], Blocks, Counter, _VRs, _BRs, Acc) ->
+ {maps:merge(Blocks, Acc), Counter}.
+
+aca_cs_block(#b_blk{is=Is0,last=Last0}=Block0, Counter0, VRs0, BRs) ->
+ {VRs, Is, Counter} = aca_cs_is(Is0, Counter0, VRs0, BRs, []),
+ Last = aca_cs_last(Last0, VRs, BRs),
+ Block = Block0#b_blk{is=Is,last=Last},
+ {VRs, Block, Counter}.
+
+aca_cs_is([#b_set{op=Op,
+ dst=Dst0,
+ args=Args0}=I0 | Is],
+ Counter0, VRs0, BRs, Acc) ->
+ Args = case Op of
+ phi -> aca_cs_args_phi(Args0, VRs0, BRs);
+ _ -> aca_cs_args(Args0, VRs0)
+ end,
+ Counter = Counter0 + 1,
+ Dst = #b_var{name={'@ssa_bsm_aca',Counter}},
+ I = I0#b_set{dst=Dst,args=Args},
+ VRs = maps:put(Dst0, Dst, VRs0),
+ aca_cs_is(Is, Counter, VRs, BRs, [I | Acc]);
+aca_cs_is([], Counter, VRs, _BRs, Acc) ->
+ {VRs, reverse(Acc), Counter}.
+
+aca_cs_last(#b_switch{arg=Arg0,list=Switch0,fail=Fail0}=Sw, VRs, BRs) ->
+ Switch = [{Literal, maps:get(Lbl, BRs)} || {Literal, Lbl} <- Switch0],
+ Sw#b_switch{arg=aca_cs_arg(Arg0, VRs),
+ fail=maps:get(Fail0, BRs),
+ list=Switch};
+aca_cs_last(#b_br{bool=Arg0,succ=Succ0,fail=Fail0}=Br, VRs, BRs) ->
+ Br#b_br{bool=aca_cs_arg(Arg0, VRs),
+ succ=maps:get(Succ0, BRs),
+ fail=maps:get(Fail0, BRs)};
+aca_cs_last(#b_ret{arg=Arg0}=Ret, VRs, _BRs) ->
+ Ret#b_ret{arg=aca_cs_arg(Arg0, VRs)}.
+
+aca_cs_args_phi([{Arg, Lbl} | Args], VRs, BRs) ->
+ case BRs of
+ #{ Lbl := New } ->
+ [{aca_cs_arg(Arg, VRs), New} | aca_cs_args_phi(Args, VRs, BRs)];
+ #{} ->
+ aca_cs_args_phi(Args, VRs, BRs)
+ end;
+aca_cs_args_phi([], _VRs, _BRs) ->
+ [].
+
+aca_cs_args([Arg | Args], VRs) ->
+ [aca_cs_arg(Arg, VRs) | aca_cs_args(Args, VRs)];
+aca_cs_args([], _VRs) ->
+ [].
+
+aca_cs_arg(Arg, VRs) ->
+ case VRs of
+ #{ Arg := New } -> New;
+ #{} -> Arg
+ end.
+
+%% Allows contexts to pass through "wrapper functions" where the context is
+%% passed directly to a function that accepts match contexts (including other
+%% wrappers).
+%%
+%% This does not alter the function in any way, it only changes parameter info
+%% so that skip_outgoing_tail_extraction is aware that it's safe to pass
+%% contexts to us.
+
+allow_context_passthrough({Fs, ModInfo0}) ->
+ ModInfo =
+ acp_forward_params([{F, beam_ssa:uses(F#b_function.bs)} || F <- Fs],
+ ModInfo0),
+ {Fs, ModInfo}.
+
+acp_forward_params(FsUses, ModInfo0) ->
+ F = fun({#b_function{args=Parameters}=Func, UseMap}, ModInfo) ->
+ ParamInfo =
+ foldl(fun(Param, ParamInfo) ->
+ Uses = maps:get(Param, UseMap, []),
+ acp_1(Param, Uses, ModInfo, ParamInfo)
+ end,
+ funcinfo_get(Func, parameter_info, ModInfo),
+ Parameters),
+ funcinfo_set(Func, parameter_info, ParamInfo, ModInfo)
+ end,
+ %% Allowing context passthrough on one function may make it possible to
+ %% enable it on another, so it needs to be repeated for maximum effect.
+ case foldl(F, ModInfo0, FsUses) of
+ ModInfo0 -> ModInfo0;
+ Changed -> acp_forward_params(FsUses, Changed)
+ end.
+
+%% We have no way to know if an argument is a context, so it's only safe to
+%% forward them if they're passed exactly once in the first block. Any other
+%% uses are unsafe, including function_clause errors.
+acp_1(Param, [{0, #b_set{op=call}=I}], ModInfo, ParamInfo) ->
+ %% We don't need to provide a context chain as our callers make sure that
+ %% multiple arguments never reference the same context.
+ case check_context_call(I, Param, [], ModInfo) of
+ {no_match_on_entry, _} -> ParamInfo;
+ Other -> maps:put(Param, Other, ParamInfo)
+ end;
+acp_1(_Param, _Uses, _ModInfo, ParamInfo) ->
+ ParamInfo.
+
+%% This is conceptually similar to combine_matches but operates across
+%% functions. Whenever a tail binary is passed to a parameter that accepts
+%% match contexts we'll pass the context instead, improving performance by
+%% avoiding the creation of a new match context in the callee.
+%%
+%% We also create an alias to delay extraction until it's needed as an actual
+%% binary, which is often rare on the happy path. The cost of being wrong is
+%% negligible (`bs_test_unit + bs_get_tail` vs `bs_get_binary`) so we're
+%% applying it unconditionally to keep things simple.
+
+-record(sote, { definitions :: beam_ssa:definition_map(),
+ mod_info :: module_info(),
+ match_aliases = #{} :: match_alias_map() }).
+
+skip_outgoing_tail_extraction({Fs0, ModInfo}) ->
+ Fs = map(fun(F) -> skip_outgoing_tail_extraction(F, ModInfo) end, Fs0),
+ {Fs, ModInfo}.
+
+skip_outgoing_tail_extraction(#b_function{bs=Blocks0}=F, ModInfo) ->
+ case funcinfo_get(F, has_bsm_ops, ModInfo) of
+ true ->
+ State0 = #sote{ definitions = beam_ssa:definitions(Blocks0),
+ mod_info = ModInfo },
+
+ {Blocks1, State} = beam_ssa:mapfold_instrs_rpo(
+ fun sote_rewrite_calls/2, [0], State0, Blocks0),
+
+ {Blocks, Counter} = alias_matched_binaries(Blocks1,
+ F#b_function.cnt,
+ State#sote.match_aliases),
+
+ F#b_function{bs=Blocks,cnt=Counter};
+ false ->
+ F
+ end.
+
+sote_rewrite_calls(#b_set{op=call,args=Args}=Call, State) ->
+ sote_rewrite_call(Call, Args, [], State);
+sote_rewrite_calls(I, State) ->
+ {I, State}.
+
+sote_rewrite_call(Call, [], ArgsOut, State) ->
+ {Call#b_set{args=reverse(ArgsOut)}, State};
+sote_rewrite_call(Call0, [Arg | ArgsIn], ArgsOut, State0) ->
+ case is_tail_binary(Arg, State0#sote.definitions) of
+ true ->
+ CtxChain = context_chain_of(Arg, State0#sote.definitions),
+ case check_context_call(Call0, Arg, CtxChain, State0#sote.mod_info) of
+ suitable_for_reuse ->
+ Ctx = match_context_of(Arg, State0#sote.definitions),
+
+ MatchAliases0 = State0#sote.match_aliases,
+ MatchAliases = maps:put(Arg, {0, Ctx}, MatchAliases0),
+ State = State0#sote{ match_aliases = MatchAliases },
+
+ Call = beam_ssa:add_anno(bsm_info, context_reused, Call0),
+ sote_rewrite_call(Call, ArgsIn, [Ctx | ArgsOut], State);
+ Other ->
+ Call = beam_ssa:add_anno(bsm_info, Other, Call0),
+ sote_rewrite_call(Call, ArgsIn, [Arg | ArgsOut], State0)
+ end;
+ false ->
+ sote_rewrite_call(Call0, ArgsIn, [Arg | ArgsOut], State0)
+ end.
+
+%% Adds parameter_type_info annotations to help the validator determine whether
+%% our optimizations were safe.
+
+annotate_context_parameters({Fs, ModInfo}) ->
+ mapfoldl(fun annotate_context_parameters/2, ModInfo, Fs).
+
+annotate_context_parameters(F, ModInfo) ->
+ ParamInfo = funcinfo_get(F, parameter_info, ModInfo),
+ TypeAnno0 = beam_ssa:get_anno(parameter_type_info, F, #{}),
+ TypeAnno = maps:fold(fun(K, _V, Acc) when is_map_key(K, Acc) ->
+ %% Assertion.
+ error(conflicting_parameter_types);
+ (K, suitable_for_reuse, Acc) ->
+ Acc#{ K => match_context };
+ (_K, _V, Acc) ->
+ Acc
+ end, TypeAnno0, ParamInfo),
+ {beam_ssa:add_anno(parameter_type_info, TypeAnno, F), ModInfo}.
+
+%%%
+%%% +bin_opt_info
+%%%
+
+collect_opt_info(Fs) ->
+ foldl(fun(#b_function{bs=Blocks}=F, Acc0) ->
+ UseMap = beam_ssa:uses(Blocks),
+ Where = beam_ssa:get_anno(location, F, []),
+ beam_ssa:fold_instrs_rpo(
+ fun(I, Acc) ->
+ collect_opt_info_1(I, Where, UseMap, Acc)
+ end, [0], Acc0, Blocks)
+ end, [], Fs).
+
+collect_opt_info_1(#b_set{op=Op,anno=Anno,dst=Dst}=I, Where, UseMap, Acc0) ->
+ case is_tail_binary(I) of
+ true when Op =:= bs_match ->
+ %% The uses include when the context is passed raw, so we discard
+ %% everything but the bs_extract instruction to limit warnings to
+ %% unoptimized uses.
+ Uses0 = maps:get(Dst, UseMap, []),
+ case [E || {_, #b_set{op=bs_extract}=E} <- Uses0] of
+ [Use] -> add_unopt_binary_info(Use, false, Where, UseMap, Acc0);
+ [] -> Acc0
+ end;
+ true ->
+ %% Add a warning for each use. Note that we don't do anything
+ %% special if unused as a later pass will remove this instruction
+ %% anyway.
+ Uses = maps:get(Dst, UseMap, []),
+ foldl(fun({_Lbl, Use}, Acc) ->
+ add_unopt_binary_info(Use, false, Where, UseMap, Acc)
+ end, Acc0, Uses);
+ false ->
+ add_opt_info(Anno, Where, Acc0)
+ end;
+collect_opt_info_1(#b_ret{anno=Anno}, Where, _UseMap, Acc) ->
+ add_opt_info(Anno, Where, Acc);
+collect_opt_info_1(_I, _Where, _Uses, Acc) ->
+ Acc.
+
+add_opt_info(Anno, Where, Acc) ->
+ case maps:find(bsm_info, Anno) of
+ {ok, Term} -> [make_warning(Term, Anno, Where) | Acc];
+ error -> Acc
+ end.
+
+%% When an alias is promoted we need to figure out where it goes to ignore
+%% warnings for compiler-generated things, and provide more useful warnings in
+%% general.
+%%
+%% We track whether the binary has been used to build another term because it
+%% can be helpful when there's no line information.
+
+add_unopt_binary_info(#b_set{op=Follow,dst=Dst}, _Nested, Where, UseMap, Acc0)
+ when Follow =:= put_tuple;
+ Follow =:= put_list;
+ Follow =:= put_map ->
+ %% Term-building instructions.
+ {_, Uses} = unzip(maps:get(Dst, UseMap, [])),
+ foldl(fun(Use, Acc) ->
+ add_unopt_binary_info(Use, true, Where, UseMap, Acc)
+ end, Acc0, Uses);
+add_unopt_binary_info(#b_set{op=Follow,dst=Dst}, Nested, Where, UseMap, Acc0)
+ when Follow =:= bs_extract;
+ Follow =:= phi ->
+ %% Non-building instructions that need to be followed.
+ {_, Uses} = unzip(maps:get(Dst, UseMap, [])),
+ foldl(fun(Use, Acc) ->
+ add_unopt_binary_info(Use, Nested, Where, UseMap, Acc)
+ end, Acc0, Uses);
+add_unopt_binary_info(#b_set{op=call,
+ args=[#b_remote{mod=#b_literal{val=erlang},
+ name=#b_literal{val=error}} |
+ _Ignored]},
+ _Nested, _Where, _UseMap, Acc) ->
+ %% There's no nice way to tell compiler-generated exceptions apart from
+ %% user ones so we ignore them all. I doubt anyone cares.
+ Acc;
+add_unopt_binary_info(#b_switch{anno=Anno}=I, Nested, Where, _UseMap, Acc) ->
+ [make_promotion_warning(I, Nested, Anno, Where) | Acc];
+add_unopt_binary_info(#b_set{anno=Anno}=I, Nested, Where, _UseMap, Acc) ->
+ [make_promotion_warning(I, Nested, Anno, Where) | Acc];
+add_unopt_binary_info(#b_ret{anno=Anno}=I, Nested, Where, _UseMap, Acc) ->
+ [make_promotion_warning(I, Nested, Anno, Where) | Acc];
+add_unopt_binary_info(#b_br{anno=Anno}=I, Nested, Where, _UseMap, Acc) ->
+ [make_promotion_warning(I, Nested, Anno, Where) | Acc].
+
+make_promotion_warning(I, Nested, Anno, Where) ->
+ make_warning({binary_created, I, Nested}, Anno, Where).
+
+make_warning(Term, Anno, Where) ->
+ {File, Line} = maps:get(location, Anno, Where),
+ {File,[{Line,?MODULE,Term}]}.
+
+format_opt_info(context_reused) ->
+ "OPTIMIZED: match context reused";
+format_opt_info({binary_created, _, _}=Promotion) ->
+ io_lib:format("BINARY CREATED: ~s", [format_opt_info_1(Promotion)]);
+format_opt_info(Other) ->
+ io_lib:format("NOT OPTIMIZED: ~s", [format_opt_info_1(Other)]).
+
+format_opt_info_1({binary_created, #b_set{op=call,args=[Call|_]}, false}) ->
+ io_lib:format("binary is used in call to ~s which doesn't support "
+ "context reuse", [format_call(Call)]);
+format_opt_info_1({binary_created, #b_set{op=call,args=[Call|_]}, true}) ->
+ io_lib:format("binary is used in term passed to ~s",
+ [format_call(Call)]);
+format_opt_info_1({binary_created, #b_set{op={bif, BIF},args=Args}, false}) ->
+ io_lib:format("binary is used in ~p/~p which doesn't support context "
+ "reuse", [BIF, length(Args)]);
+format_opt_info_1({binary_created, #b_set{op={bif, BIF},args=Args}, true}) ->
+ io_lib:format("binary is used in term passed to ~p/~p",
+ [BIF, length(Args)]);
+format_opt_info_1({binary_created, #b_set{op=Op}, false}) ->
+ io_lib:format("binary is used in '~p' which doesn't support context "
+ "reuse", [Op]);
+format_opt_info_1({binary_created, #b_set{op=Op}, true}) ->
+ io_lib:format("binary is used in term passed to '~p'", [Op]);
+format_opt_info_1({binary_created, #b_ret{}, false}) ->
+ io_lib:format("binary is returned from the function", []);
+format_opt_info_1({binary_created, #b_ret{}, true}) ->
+ io_lib:format("binary is used in a term that is returned from the "
+ "function", []);
+format_opt_info_1({unsuitable_call, {Call, Inner}}) ->
+ io_lib:format("binary used in call to ~s, where ~s",
+ [format_call(Call), format_opt_info_1(Inner)]);
+format_opt_info_1({remote_call, Call}) ->
+ io_lib:format("binary is used in remote call to ~s", [format_call(Call)]);
+format_opt_info_1({fun_call, Call}) ->
+ io_lib:format("binary is used in fun call (~s)",
+ [format_call(Call)]);
+format_opt_info_1({multiple_uses_in_call, Call}) ->
+ io_lib:format("binary is passed as multiple arguments to ~s",
+ [format_call(Call)]);
+format_opt_info_1({no_match_on_entry, Call}) ->
+ io_lib:format("binary is used in call to ~s which does not begin with a "
+ "suitable binary match", [format_call(Call)]);
+format_opt_info_1({used_before_match, #b_set{op=call,args=[Call|_]}}) ->
+ io_lib:format("binary is used in call to ~s before being matched",
+ [format_call(Call)]);
+format_opt_info_1({used_before_match, #b_set{op={bif, BIF},args=Args}}) ->
+ io_lib:format("binary is used in ~p/~p before being matched",
+ [BIF, length(Args)]);
+format_opt_info_1({used_before_match, #b_set{op=phi}}) ->
+ io_lib:format("binary is returned from an expression before being "
+ "matched", []);
+format_opt_info_1({used_before_match, #b_set{op=Op}}) ->
+ io_lib:format("binary is used in '~p' before being matched",[Op]);
+format_opt_info_1(Term) ->
+ io_lib:format("~w", [Term]).
+
+format_call(#b_local{name=#b_literal{val=F},arity=A}) ->
+ io_lib:format("~p/~p", [F, A]);
+format_call(#b_remote{mod=#b_literal{val=M},name=#b_literal{val=F},arity=A}) ->
+ io_lib:format("~p:~p/~p", [M, F, A]);
+format_call(Fun) ->
+ io_lib:format("~p", [Fun]).
diff --git a/lib/compiler/src/beam_ssa_codegen.erl b/lib/compiler/src/beam_ssa_codegen.erl
index 5085c950b5..1c7563faa0 100644
--- a/lib/compiler/src/beam_ssa_codegen.erl
+++ b/lib/compiler/src/beam_ssa_codegen.erl
@@ -108,7 +108,8 @@ module(#b_module{name=Mod,exports=Es,attributes=Attrs,body=Fs}, _Opts) ->
-type ssa_register() :: xreg() | yreg() | {'fr',reg_num()} | {'z',reg_num()}.
functions(Forms, AtomMod) ->
- mapfoldl(fun (F, St) -> function(F, AtomMod, St) end, #cg{lcount=1}, Forms).
+ mapfoldl(fun (F, St) -> function(F, AtomMod, St) end,
+ #cg{lcount=1}, Forms).
function(#b_function{anno=Anno,bs=Blocks}, AtomMod, St0) ->
#{func_info:={_,Name,Arity}} = Anno,
@@ -125,8 +126,9 @@ function(#b_function{anno=Anno,bs=Blocks}, AtomMod, St0) ->
ultimate_fail=Ult},
{Body,St} = cg_fun(Blocks, St5),
Asm = [{label,Fi},line(Anno),
- {func_info,AtomMod,{atom,Name},Arity}] ++ Body ++
- [{label,Ult},if_end],
+ {func_info,AtomMod,{atom,Name},Arity}] ++
+ add_parameter_annos(Body, Anno) ++
+ [{label,Ult},if_end],
Func = {function,Name,Arity,Entry,Asm},
{Func,St}
catch
@@ -150,6 +152,17 @@ assert_badarg_block(Blocks) ->
ok
end.
+add_parameter_annos([{label, _}=Entry | Body], Anno) ->
+ ParamInfo = maps:get(parameter_type_info, Anno, #{}),
+ Annos = maps:fold(
+ fun(K, V, Acc) when is_map_key(K, ParamInfo) ->
+ TypeInfo = maps:get(K, ParamInfo),
+ [{'%', {type_info, V, TypeInfo}} | Acc];
+ (_K, _V, Acc) ->
+ Acc
+ end, [], maps:get(registers, Anno)),
+ [Entry | Annos] ++ Body.
+
cg_fun(Blocks, St0) ->
Linear0 = linearize(Blocks),
St = collect_catch_labels(Linear0, St0),
@@ -315,12 +328,15 @@ classify_heap_need(Name, _Args) ->
classify_heap_need(bs_add) -> gc;
classify_heap_need(bs_get) -> gc;
+classify_heap_need(bs_get_tail) -> gc;
classify_heap_need(bs_init) -> gc;
classify_heap_need(bs_init_writable) -> gc;
classify_heap_need(bs_match_string) -> gc;
classify_heap_need(bs_put) -> neutral;
classify_heap_need(bs_restore) -> neutral;
classify_heap_need(bs_save) -> neutral;
+classify_heap_need(bs_get_position) -> gc;
+classify_heap_need(bs_set_position) -> neutral;
classify_heap_need(bs_skip) -> gc;
classify_heap_need(bs_start_match) -> neutral;
classify_heap_need(bs_test_tail) -> neutral;
@@ -329,7 +345,6 @@ classify_heap_need(bs_utf8_size) -> neutral;
classify_heap_need(build_stacktrace) -> gc;
classify_heap_need(call) -> gc;
classify_heap_need(catch_end) -> gc;
-classify_heap_need(context_to_binary) -> gc;
classify_heap_need(copy) -> neutral;
classify_heap_need(extract) -> gc;
classify_heap_need(get_hd) -> neutral;
@@ -695,6 +710,8 @@ need_live_anno(Op) ->
{bif,_} -> true;
bs_get -> true;
bs_init -> true;
+ bs_get_position -> true;
+ bs_get_tail -> true;
bs_start_match -> true;
bs_skip -> true;
call -> true;
@@ -794,6 +811,8 @@ def_successors([], _, DefMap) -> DefMap.
need_y_init(#cg_set{anno=#{clobbers:=Clobbers}}) -> Clobbers;
need_y_init(#cg_set{op=bs_get}) -> true;
+need_y_init(#cg_set{op=bs_get_position}) -> true;
+need_y_init(#cg_set{op=bs_get_tail}) -> true;
need_y_init(#cg_set{op=bs_init}) -> true;
need_y_init(#cg_set{op=bs_skip,args=[#b_literal{val=Type}|_]}) ->
case Type of
@@ -1042,12 +1061,18 @@ cg_block([#cg_set{op=bs_init,dst=Dst0,args=Args0,anno=Anno}=I,
end;
cg_block([#cg_set{anno=Anno,op=bs_start_match,dst=Ctx0,args=[Bin0]}=I,
#cg_set{op=succeeded,dst=Bool}], {Bool,Fail}, St) ->
- #{num_slots:=Slots} = Anno,
[Dst,Bin1] = beam_args([Ctx0,Bin0], St),
{Bin,Pre} = force_reg(Bin1, Dst),
Live = get_live(I),
- Is = Pre ++ [{test,bs_start_match2,Fail,Live,[Bin,Slots],Dst}],
- {Is,St};
+ %% num_slots is only set when using the old instructions.
+ case maps:find(num_slots, Anno) of
+ {ok, Slots} ->
+ Is = Pre ++ [{test,bs_start_match2,Fail,Live,[Bin,Slots],Dst}],
+ {Is,St};
+ error ->
+ Is = Pre ++ [{test,bs_start_match3,Fail,Live,[Bin],Dst}],
+ {Is,St}
+ end;
cg_block([#cg_set{op=bs_get}=Set,
#cg_set{op=succeeded,dst=Bool}], {Bool,Fail}, St) ->
{cg_bs_get(Fail, Set, St),St};
@@ -1344,6 +1369,12 @@ build_apply(Arity, none, Dst) ->
cg_instr(put_map, [{atom,assoc},SrcMap|Ss], Dst, Set) ->
Live = get_live(Set),
[{put_map_assoc,{f,0},SrcMap,Dst,Live,{list,Ss}}];
+cg_instr(bs_get_tail, [Src], Dst, Set) ->
+ Live = get_live(Set),
+ [{bs_get_tail,Src,Dst,Live}];
+cg_instr(bs_get_position, [Ctx], Dst, Set) ->
+ Live = get_live(Set),
+ [{bs_get_position,Ctx,Dst,Live}];
cg_instr(Op, Args, Dst, _Set) ->
cg_instr(Op, Args, Dst).
@@ -1359,10 +1390,10 @@ cg_instr(bs_restore, [Ctx,Slot], _Dst) ->
cg_instr(bs_save, [Ctx,Slot], _Dst) ->
{integer,N} = Slot,
[{bs_save2,Ctx,N}];
+cg_instr(bs_set_position, [Ctx,Pos], _Dst) ->
+ [{bs_set_position,Ctx,Pos}];
cg_instr(build_stacktrace, Args, Dst) ->
setup_args(Args) ++ [build_stacktrace|copy({x,0}, Dst)];
-cg_instr(context_to_binary, [Src], _Dst) ->
- [{bs_context_to_binary,Src}];
cg_instr(set_tuple_element=Op, [New,Tuple,{integer,Index}], _Dst) ->
[{Op,New,Tuple,Index}];
cg_instr({float,clearerror}, [], _Dst) ->
diff --git a/lib/compiler/src/beam_ssa_opt.erl b/lib/compiler/src/beam_ssa_opt.erl
index 89cfbd7a84..ac2d943fef 100644
--- a/lib/compiler/src/beam_ssa_opt.erl
+++ b/lib/compiler/src/beam_ssa_opt.erl
@@ -66,13 +66,15 @@ passes(Opts0) ->
?PASS(ssa_opt_live), %Second time.
?PASS(ssa_opt_bsm),
+ ?PASS(ssa_opt_bsm_units),
?PASS(ssa_opt_bsm_shortcut),
?PASS(ssa_opt_misc),
?PASS(ssa_opt_tuple_size),
?PASS(ssa_opt_sw),
?PASS(ssa_opt_blockify),
?PASS(ssa_opt_sink),
- ?PASS(ssa_opt_merge_blocks)],
+ ?PASS(ssa_opt_merge_blocks),
+ ?PASS(ssa_opt_trim_unreachable)],
Negations = [{list_to_atom("no_"++atom_to_list(N)),N} ||
{N,_} <- Ps],
Opts = proplists:substitute_negations(Negations, Opts0),
@@ -112,6 +114,9 @@ ssa_opt_type(#st{ssa=Linear,args=Args}=St) ->
ssa_opt_blockify(#st{ssa=Linear}=St) ->
St#st{ssa=maps:from_list(Linear)}.
+ssa_opt_trim_unreachable(#st{ssa=Blocks}=St) ->
+ St#st{ssa=beam_ssa:trim_unreachable(Blocks)}.
+
%%%
%%% Split blocks before certain instructions to enable more optimizations.
%%%
@@ -1002,6 +1007,110 @@ bsm_shortcut([{L,#b_blk{is=Is,last=Last0}=Blk}|Bs], PosMap) ->
bsm_shortcut([], _PosMap) -> [].
%%%
+%%% Eliminate redundant bs_test_unit2 instructions.
+%%%
+
+ssa_opt_bsm_units(#st{ssa=Linear}=St) ->
+ St#st{ssa=bsm_units(Linear, #{})}.
+
+bsm_units([{L,#b_blk{last=#b_br{succ=Succ,fail=Fail}}=Block0} | Bs], UnitMaps0) ->
+ UnitsIn = maps:get(L, UnitMaps0, #{}),
+ {Block, UnitsOut} = bsm_units_skip(Block0, UnitsIn),
+ UnitMaps1 = bsm_units_join(Succ, UnitsOut, UnitMaps0),
+ UnitMaps = bsm_units_join(Fail, UnitsIn, UnitMaps1),
+ [{L, Block} | bsm_units(Bs, UnitMaps)];
+bsm_units([{L,#b_blk{last=#b_switch{fail=Fail,list=Switch}}=Block} | Bs], UnitMaps0) ->
+ UnitsIn = maps:get(L, UnitMaps0, #{}),
+ Labels = [Fail | [Lbl || {_Arg, Lbl} <- Switch]],
+ UnitMaps = foldl(fun(Lbl, UnitMaps) ->
+ bsm_units_join(Lbl, UnitsIn, UnitMaps)
+ end, UnitMaps0, Labels),
+ [{L, Block} | bsm_units(Bs, UnitMaps)];
+bsm_units([{L, Block} | Bs], UnitMaps) ->
+ [{L, Block} | bsm_units(Bs, UnitMaps)];
+bsm_units([], _UnitMaps) ->
+ [].
+
+bsm_units_skip(Block, Units) ->
+ bsm_units_skip_1(Block#b_blk.is, Block, Units).
+
+bsm_units_skip_1([#b_set{op=bs_start_match,dst=New}|_], Block, Units) ->
+ %% We bail early since there can't be more than one match per block.
+ {Block, Units#{ New => 1 }};
+bsm_units_skip_1([#b_set{op=bs_match,
+ dst=New,
+ args=[#b_literal{val=skip},
+ Ctx,
+ #b_literal{val=binary},
+ _Flags,
+ #b_literal{val=all},
+ #b_literal{val=OpUnit}]}=Skip | Test],
+ Block0, Units) ->
+ [#b_set{op=succeeded,dst=Bool,args=[New]}] = Test, %Assertion.
+ #b_br{bool=Bool} = Last0 = Block0#b_blk.last, %Assertion.
+ CtxUnit = maps:get(Ctx, Units),
+ if
+ CtxUnit rem OpUnit =:= 0 ->
+ Is = takewhile(fun(I) -> I =/= Skip end, Block0#b_blk.is),
+ Last = Last0#b_br{bool=#b_literal{val=true}},
+ Block = Block0#b_blk{is=Is,last=Last},
+ {Block, Units#{ New => CtxUnit }};
+ CtxUnit rem OpUnit =/= 0 ->
+ {Block0, Units#{ New => OpUnit, Ctx => OpUnit }}
+ end;
+bsm_units_skip_1([#b_set{op=bs_match,dst=New,args=Args}|_], Block, Units) ->
+ [_,Ctx|_] = Args,
+ CtxUnit = maps:get(Ctx, Units),
+ OpUnit = bsm_op_unit(Args),
+ {Block, Units#{ New => gcd(OpUnit, CtxUnit) }};
+bsm_units_skip_1([_I | Is], Block, Units) ->
+ bsm_units_skip_1(Is, Block, Units);
+bsm_units_skip_1([], Block, Units) ->
+ {Block, Units}.
+
+bsm_op_unit([_,_,_,Size,#b_literal{val=U}]) ->
+ case Size of
+ #b_literal{val=Sz} when is_integer(Sz) -> Sz*U;
+ _ -> U
+ end;
+bsm_op_unit([#b_literal{val=string},_,#b_literal{val=String}]) ->
+ bit_size(String);
+bsm_op_unit([#b_literal{val=utf8}|_]) ->
+ 8;
+bsm_op_unit([#b_literal{val=utf16}|_]) ->
+ 16;
+bsm_op_unit([#b_literal{val=utf32}|_]) ->
+ 32;
+bsm_op_unit(_) ->
+ 1.
+
+%% Several paths can lead to the same match instruction and the inferred units
+%% may differ between them, so we can only keep the information that is common
+%% to all paths.
+bsm_units_join(Lbl, MapA, UnitMaps0) when is_map_key(Lbl, UnitMaps0) ->
+ MapB = maps:get(Lbl, UnitMaps0),
+ Merged = if
+ map_size(MapB) =< map_size(MapA) ->
+ bsm_units_join_1(maps:keys(MapB), MapA, MapB);
+ map_size(MapB) > map_size(MapA) ->
+ bsm_units_join_1(maps:keys(MapA), MapB, MapA)
+ end,
+ maps:put(Lbl, Merged, UnitMaps0);
+bsm_units_join(Lbl, MapA, UnitMaps0) when MapA =/= #{} ->
+ maps:put(Lbl, MapA, UnitMaps0);
+bsm_units_join(_Lbl, _MapA, UnitMaps0) ->
+ UnitMaps0.
+
+bsm_units_join_1([Key | Keys], Left, Right) when is_map_key(Key, Left) ->
+ UnitA = maps:get(Key, Left),
+ UnitB = maps:get(Key, Right),
+ bsm_units_join_1(Keys, Left, maps:put(Key, gcd(UnitA, UnitB), Right));
+bsm_units_join_1([Key | Keys], Left, Right) ->
+ bsm_units_join_1(Keys, Left, maps:remove(Key, Right));
+bsm_units_join_1([], _MapA, Right) ->
+ Right.
+
+%%%
%%% Miscellanous optimizations in execution order.
%%%
@@ -1618,6 +1727,12 @@ insert_def_is([], _V, Def) ->
%%% Common utilities.
%%%
+gcd(A, B) ->
+ case A rem B of
+ 0 -> B;
+ X -> gcd(B, X)
+ end.
+
rel2fam(S0) ->
S1 = sofs:relation(S0),
S = sofs:rel2fam(S1),
diff --git a/lib/compiler/src/beam_ssa_pre_codegen.erl b/lib/compiler/src/beam_ssa_pre_codegen.erl
index ca3b792ed6..36137ef046 100644
--- a/lib/compiler/src/beam_ssa_pre_codegen.erl
+++ b/lib/compiler/src/beam_ssa_pre_codegen.erl
@@ -78,15 +78,14 @@
{'ok',beam_ssa:b_module()}.
module(#b_module{body=Fs0}=Module, Opts) ->
- FixTuples = proplists:get_bool(no_put_tuple2, Opts),
- ExtraAnnos = proplists:get_bool(dprecg, Opts),
- Ps = passes(FixTuples, ExtraAnnos),
- Fs = functions(Fs0, Ps),
+ UseBSM3 = not proplists:get_bool(no_bsm3, Opts),
+ Ps = passes(Opts),
+ Fs = functions(Fs0, Ps, UseBSM3),
{ok,Module#b_module{body=Fs}}.
-functions([F|Fs], Ps) ->
- [function(F, Ps)|functions(Fs, Ps)];
-functions([], _Ps) -> [].
+functions([F|Fs], Ps, UseBSM3) ->
+ [function(F, Ps, UseBSM3)|functions(Fs, Ps, UseBSM3)];
+functions([], _Ps, _UseBSM3) -> [].
-type b_var() :: beam_ssa:b_var().
-type var_name() :: beam_ssa:var_name().
@@ -104,16 +103,18 @@ functions([], _Ps) -> [].
-record(st, {ssa :: beam_ssa:block_map(),
args :: [b_var()],
cnt :: beam_ssa:label(),
+ use_bsm3 :: boolean(),
frames=[] :: [beam_ssa:label()],
intervals=[] :: [{b_var(),[range()]}],
- aliases=[] :: [{b_var(),b_var()}],
res=[] :: [{b_var(),reservation()}] | #{b_var():=reservation()},
regs=#{} :: #{b_var():=ssa_register()},
extra_annos=[] :: [{atom(),term()}]
}).
-define(PASS(N), {N,fun N/1}).
-passes(FixTuples, ExtraAnnos) ->
+passes(Opts) ->
+ AddPrecgAnnos = proplists:get_bool(dprecg, Opts),
+ FixTuples = proplists:get_bool(no_put_tuple2, Opts),
Ps = [?PASS(assert_no_critical_edges),
%% Preliminaries.
@@ -138,27 +139,25 @@ passes(FixTuples, ExtraAnnos) ->
%% Calculate live intervals.
?PASS(number_instructions),
?PASS(live_intervals),
- ?PASS(remove_unsuitable_aliases),
?PASS(reserve_regs),
- ?PASS(merge_intervals),
%% If needed for a .precg file, save the live intervals
%% so they can be included in an annotation.
- case ExtraAnnos of
+ case AddPrecgAnnos of
false -> ignore;
true -> ?PASS(save_live_intervals)
end,
%% Allocate registers.
?PASS(linear_scan),
- ?PASS(fix_aliased_regs),
?PASS(frame_size),
?PASS(turn_yregs)],
[P || P <- Ps, P =/= ignore].
-function(#b_function{anno=Anno,args=Args,bs=Blocks0,cnt=Count0}=F0, Ps) ->
+function(#b_function{anno=Anno,args=Args,bs=Blocks0,cnt=Count0}=F0,
+ Ps, UseBSM3) ->
try
- St0 = #st{ssa=Blocks0,args=Args,cnt=Count0},
+ St0 = #st{ssa=Blocks0,args=Args,use_bsm3=UseBSM3,cnt=Count0},
St = compile:run_sub_passes(Ps, St0),
#st{ssa=Blocks,cnt=Count,regs=Regs,extra_annos=ExtraAnnos} = St,
F1 = add_extra_annos(F0, ExtraAnnos),
@@ -174,14 +173,6 @@ function(#b_function{anno=Anno,args=Args,bs=Blocks0,cnt=Count0}=F0, Ps) ->
save_live_intervals(#st{intervals=Intervals}=St) ->
St#st{extra_annos=[{live_intervals,Intervals}]}.
-fix_aliased_regs(#st{aliases=Aliases,regs=Regs}=St) ->
- St#st{regs=fix_aliased_regs(Aliases, Regs)}.
-
-fix_aliased_regs([{Alias,V}|Aliases], Regs) ->
- #{V:=Reg} = Regs,
- fix_aliased_regs(Aliases, Regs#{Alias=>Reg});
-fix_aliased_regs([], Regs) -> Regs.
-
%% Add extra annotations when a .precg listing file is being produced.
add_extra_annos(F, Annos) ->
foldl(fun({Name,Value}, Acc) ->
@@ -214,7 +205,7 @@ assert_no_ces(_, _, Blocks) -> Blocks.
%% * Combine bs_match and bs_extract instructions to bs_get
%% instructions.
-fix_bs(#st{ssa=Blocks,cnt=Count0}=St) ->
+fix_bs(#st{ssa=Blocks,cnt=Count0,use_bsm3=UseBSM3}=St) ->
F = fun(#b_set{op=bs_start_match,dst=Dst}, A) ->
%% Mark the root of the match context list.
[{Dst,{context,Dst}}|A];
@@ -232,8 +223,13 @@ fix_bs(#st{ssa=Blocks,cnt=Count0}=St) ->
CtxChain = maps:from_list(M),
Linear0 = beam_ssa:linearize(Blocks),
- %% Insert bs_save / bs_restore instructions where needed.
- {Linear1,Count} = bs_save_restore(Linear0, CtxChain, Count0),
+ %% Insert position instructions where needed.
+ {Linear1,Count} = case UseBSM3 of
+ true ->
+ bs_pos_bsm3(Linear0, CtxChain, Count0);
+ false ->
+ bs_pos_bsm2(Linear0, CtxChain, Count0)
+ end,
%% Rename instructions.
Linear = bs_instrs(Linear1, CtxChain, []),
@@ -241,10 +237,54 @@ fix_bs(#st{ssa=Blocks,cnt=Count0}=St) ->
St#st{ssa=maps:from_list(Linear),cnt=Count}
end.
+%% Insert bs_get_position and bs_set_position instructions as needed.
+bs_pos_bsm3(Linear0, CtxChain, Count0) ->
+ Rs0 = bs_restores(Linear0, CtxChain, #{}, #{}),
+ Rs = maps:values(Rs0),
+ S0 = sofs:relation(Rs, [{context,save_point}]),
+ S1 = sofs:relation_to_family(S0),
+ S = sofs:to_external(S1),
+
+ {SavePoints,Count1} = make_bs_pos_dict(S, Count0, []),
+ {Gets,Count2} = make_bs_setpos_map(Rs, SavePoints, Count1, []),
+ {Sets,Count} = make_bs_getpos_map(maps:to_list(Rs0), SavePoints, Count2, []),
+
+ %% Now insert all saves and restores.
+ {bs_insert_bsm3(Linear0, Gets, Sets, SavePoints),Count}.
+
+make_bs_setpos_map([{Ctx,Save}=Ps|T], SavePoints, Count, Acc) ->
+ SavePoint = get_savepoint(Ps, SavePoints),
+ I = #b_set{op=bs_get_position,dst=SavePoint,args=[Ctx]},
+ make_bs_setpos_map(T, SavePoints, Count+1, [{Save,I}|Acc]);
+make_bs_setpos_map([], _, Count, Acc) ->
+ {maps:from_list(Acc),Count}.
+
+make_bs_getpos_map([{Bef,{Ctx,_}=Ps}|T], SavePoints, Count, Acc) ->
+ Ignored = #b_var{name={'@ssa_ignored',Count}},
+ Args = [Ctx, get_savepoint(Ps, SavePoints)],
+ I = #b_set{op=bs_set_position,dst=Ignored,args=Args},
+ make_bs_getpos_map(T, SavePoints, Count+1, [{Bef,I}|Acc]);
+make_bs_getpos_map([], _, Count, Acc) ->
+ {maps:from_list(Acc),Count}.
+
+get_savepoint({_,_}=Ps, SavePoints) ->
+ Name = {'@ssa_bs_position', maps:get(Ps, SavePoints)},
+ #b_var{name=Name}.
-%% Insert bs_save and bs_restore instructions as needed.
+make_bs_pos_dict([{Ctx,Pts}|T], Count0, Acc0) ->
+ {Acc, Count} = make_bs_pos_dict_1(Pts, Ctx, Count0, Acc0),
+ make_bs_pos_dict(T, Count, Acc);
+make_bs_pos_dict([], Count, Acc) ->
+ {maps:from_list(Acc), Count}.
-bs_save_restore(Linear0, CtxChain, Count0) ->
+make_bs_pos_dict_1([H|T], Ctx, I, Acc) ->
+ make_bs_pos_dict_1(T, Ctx, I+1, [{{Ctx,H},I}|Acc]);
+make_bs_pos_dict_1([], Ctx, I, Acc) ->
+ {[{Ctx,I}|Acc], I}.
+
+%% As bs_position but without OTP-22 instructions. This is only used when
+%% cross-compiling to older versions.
+bs_pos_bsm2(Linear0, CtxChain, Count0) ->
Rs0 = bs_restores(Linear0, CtxChain, #{}, #{}),
Rs = maps:values(Rs0),
S0 = sofs:relation(Rs, [{context,save_point}]),
@@ -255,7 +295,7 @@ bs_save_restore(Linear0, CtxChain, Count0) ->
{Restores,Count} = make_restore_map(maps:to_list(Rs0), Slots, Count1, []),
%% Now insert all saves and restores.
- {bs_insert(Linear0, Saves, Restores, Slots),Count}.
+ {bs_insert_bsm2(Linear0, Saves, Restores, Slots),Count}.
make_save_map([{Ctx,Save}=Ps|T], Slots, Count, Acc) ->
Ignored = #b_var{name={'@ssa_ignored',Count}},
@@ -308,8 +348,7 @@ bs_restores([], _, _, Rs) -> Rs.
bs_update_successors(#b_br{succ=Succ,fail=Fail}, SPos, FPos, D) ->
join_positions([{Succ,SPos},{Fail,FPos}], D);
-bs_update_successors(#b_switch{fail=Fail,list=List}, SPos, FPos, D) ->
- SPos = FPos, %Assertion.
+bs_update_successors(#b_switch{fail=Fail,list=List}, SPos, _FPos, D) ->
Update = [{L,SPos} || {_,L} <- List] ++ [{Fail,SPos}],
join_positions(Update, D);
bs_update_successors(#b_ret{}, _, _, D) -> D.
@@ -388,10 +427,19 @@ bs_restores_is([#b_set{op=bs_extract,args=[FromPos|_]}|Is],
Start = bs_subst_ctx(FromPos, CtxChain),
#{Start:=FromPos} = PosMap, %Assertion.
bs_restores_is(Is, CtxChain, PosMap, Rs);
+bs_restores_is([#b_set{op=call,dst=Dst,args=Args}|Is],
+ CtxChain, PosMap0, Rs0) ->
+ {Rs,PosMap1} = bs_restore_args(Args, PosMap0, CtxChain, Dst, Rs0),
+ PosMap = bs_invalidate_pos(Args, PosMap1, CtxChain),
+ bs_restores_is(Is, CtxChain, PosMap, Rs);
+bs_restores_is([#b_set{op=landingpad}|Is], CtxChain, PosMap0, Rs) ->
+ %% We can land here from any point, so all positions are invalid.
+ PosMap = maps:map(fun(_Start,_Pos) -> unknown end, PosMap0),
+ bs_restores_is(Is, CtxChain, PosMap, Rs);
bs_restores_is([#b_set{op=Op,dst=Dst,args=Args}|Is],
CtxChain, PosMap0, Rs0)
when Op =:= bs_test_tail;
- Op =:= call ->
+ Op =:= bs_get_tail ->
{Rs,PosMap} = bs_restore_args(Args, PosMap0, CtxChain, Dst, Rs0),
bs_restores_is(Is, CtxChain, PosMap, Rs);
bs_restores_is([_|Is], CtxChain, PosMap, Rs) ->
@@ -399,7 +447,6 @@ bs_restores_is([_|Is], CtxChain, PosMap, Rs) ->
bs_restores_is([], _CtxChain, PosMap, Rs) ->
{PosMap,Rs}.
-
bs_match_type(#b_set{args=[#b_literal{val=skip},_Ctx,
#b_literal{val=binary},_Flags,
#b_literal{val=all},#b_literal{val=U}]}) ->
@@ -410,6 +457,23 @@ bs_match_type(#b_set{args=[#b_literal{val=skip},_Ctx,
bs_match_type(_) ->
plain.
+%% Call instructions leave the match position in an undefined state,
+%% requiring us to invalidate each affected argument.
+bs_invalidate_pos([#b_var{}=Arg|Args], PosMap0, CtxChain) ->
+ Start = bs_subst_ctx(Arg, CtxChain),
+ case PosMap0 of
+ #{Start:=_} ->
+ PosMap = PosMap0#{Start:=unknown},
+ bs_invalidate_pos(Args, PosMap, CtxChain);
+ #{} ->
+ %% Not a match context.
+ bs_invalidate_pos(Args, PosMap0, CtxChain)
+ end;
+bs_invalidate_pos([_|Args], PosMap, CtxChain) ->
+ bs_invalidate_pos(Args, PosMap, CtxChain);
+bs_invalidate_pos([], PosMap, _CtxChain) ->
+ PosMap.
+
bs_restore_args([#b_var{}=Arg|Args], PosMap0, CtxChain, Dst, Rs0) ->
Start = bs_subst_ctx(Arg, CtxChain),
case PosMap0 of
@@ -432,33 +496,45 @@ bs_restore_args([], PosMap, _CtxChain, _Dst, Rs) ->
%% Insert all bs_save and bs_restore instructions.
-bs_insert([{L,#b_blk{is=Is0}=Blk}|Bs0], Saves, Restores, Slots) ->
- Is = bs_insert_is_1(Is0, Restores, Slots),
+bs_insert_bsm3(Blocks, Saves, Restores, SavePoints) ->
+ bs_insert_1(Blocks, Saves, Restores, SavePoints, fun(I) -> I end).
+
+bs_insert_bsm2(Blocks, Saves, Restores, SavePoints) ->
+ %% The old instructions require bs_start_match to be annotated with the
+ %% number of position slots it needs.
+ bs_insert_1(Blocks, Saves, Restores, SavePoints,
+ fun(#b_set{op=bs_start_match,dst=Dst}=I0) ->
+ NumSlots = case SavePoints of
+ #{Dst:=NumSlots0} -> NumSlots0;
+ #{} -> 0
+ end,
+ beam_ssa:add_anno(num_slots, NumSlots, I0);
+ (I) ->
+ I
+ end).
+
+bs_insert_1([{L,#b_blk{is=Is0}=Blk}|Bs0], Saves, Restores, Slots, XFrm) ->
+ Is = bs_insert_is_1(Is0, Restores, Slots, XFrm),
Bs = bs_insert_saves(Is, Bs0, Saves),
- [{L,Blk#b_blk{is=Is}}|bs_insert(Bs, Saves, Restores, Slots)];
-bs_insert([], _, _, _) -> [].
+ [{L,Blk#b_blk{is=Is}}|bs_insert_1(Bs, Saves, Restores, Slots, XFrm)];
+bs_insert_1([], _, _, _, _) -> [].
-bs_insert_is_1([#b_set{op=Op,dst=Dst}=I0|Is], Restores, Slots) ->
+bs_insert_is_1([#b_set{op=Op,dst=Dst}=I0|Is], Restores, SavePoints, XFrm) ->
+ I = XFrm(I0),
if
Op =:= bs_test_tail;
+ Op =:= bs_get_tail;
Op =:= bs_match;
Op =:= call ->
Rs = case Restores of
#{Dst:=R} -> [R];
#{} -> []
end,
- Rs ++ [I0|bs_insert_is_1(Is, Restores, Slots)];
- Op =:= bs_start_match ->
- NumSlots = case Slots of
- #{Dst:=NumSlots0} -> NumSlots0;
- #{} -> 0
- end,
- I = beam_ssa:add_anno(num_slots, NumSlots, I0),
- [I|bs_insert_is_1(Is, Restores, Slots)];
+ Rs ++ [I|bs_insert_is_1(Is, Restores, SavePoints, XFrm)];
true ->
- [I0|bs_insert_is_1(Is, Restores, Slots)]
+ [I|bs_insert_is_1(Is, Restores, SavePoints, XFrm)]
end;
-bs_insert_is_1([], _, _) -> [].
+bs_insert_is_1([], _, _, _) -> [].
bs_insert_saves([#b_set{dst=Dst}|Is], Bs, Saves) ->
case Saves of
@@ -504,6 +580,8 @@ bs_instrs_is([#b_set{op=Op,args=Args0}=I0|Is], CtxChain, Acc) ->
I1#b_set{op=bs_skip,args=[Type,Ctx|As]};
{bs_match,[#b_literal{val=string},Ctx|As]} ->
I1#b_set{op=bs_match_string,args=[Ctx|As]};
+ {bs_get_tail,[Ctx|As]} ->
+ I1#b_set{op=bs_get_tail,args=[Ctx|As]};
{_,_} ->
I1
end,
@@ -1520,10 +1598,10 @@ live_intervals(#st{args=Args,ssa=Blocks}=St) ->
Vars0 = [{V,{0,1}} || #b_var{}=V <- Args],
F = fun(L, _, A) -> live_interval_blk(L, Blocks, A) end,
LiveMap0 = #{},
- Acc0 = {[],[],LiveMap0},
- {Vars,Aliases,_} = beam_ssa:fold_po(F, Acc0, Blocks),
+ Acc0 = {[],LiveMap0},
+ {Vars,_} = beam_ssa:fold_po(F, Acc0, Blocks),
Intervals = merge_ranges(rel2fam(Vars0++Vars)),
- St#st{intervals=Intervals,aliases=Aliases}.
+ St#st{intervals=Intervals}.
merge_ranges([{V,Rs}|T]) ->
[{V,merge_ranges_1(Rs)}|merge_ranges(T)];
@@ -1535,7 +1613,7 @@ merge_ranges_1([R|Rs]) ->
[R|merge_ranges_1(Rs)];
merge_ranges_1([]) -> [].
-live_interval_blk(L, Blocks, {Vars0,Aliases0,LiveMap0}) ->
+live_interval_blk(L, Blocks, {Vars0,LiveMap0}) ->
Live0 = [],
Successors = beam_ssa:successors(L, Blocks),
Live1 = update_successors(Successors, L, Blocks, LiveMap0, Live0),
@@ -1547,8 +1625,7 @@ live_interval_blk(L, Blocks, {Vars0,Aliases0,LiveMap0}) ->
%% Determine used and defined variables in this block.
FirstNumber = first_number(Is, Last),
- {UseDef0,Aliases} = live_interval_blk_1([Last|reverse(Is)],
- FirstNumber, Aliases0, Use),
+ UseDef0 = live_interval_blk_1([Last|reverse(Is)], FirstNumber, Use),
UseDef = rel2fam(UseDef0),
%% Update what is live at the beginning of this block and
@@ -1561,7 +1638,7 @@ live_interval_blk(L, Blocks, {Vars0,Aliases0,LiveMap0}) ->
%% Construct the ranges for this block.
Vars = make_block_ranges(UseDef, FirstNumber, Vars0),
- {Vars,Aliases,LiveMap}.
+ {Vars,LiveMap}.
make_block_ranges([{V,[{def,Def}]}|Vs], First, Acc) ->
make_block_ranges(Vs, First, [{V,{Def,Def}}|Acc]);
@@ -1573,25 +1650,17 @@ make_block_ranges([{V,[{use,_}|_]=Uses}|Vs], First, Acc) ->
make_block_ranges(Vs, First, [{V,{First,Last}}|Acc]);
make_block_ranges([], _, Acc) -> Acc.
-live_interval_blk_1([#b_set{op=phi,dst=Dst}|Is],
- FirstNumber, Aliases, Acc0) ->
+live_interval_blk_1([#b_set{op=phi,dst=Dst}|Is], FirstNumber, Acc0) ->
Acc = [{Dst,{def,FirstNumber}}|Acc0],
- live_interval_blk_1(Is, FirstNumber, Aliases, Acc);
-live_interval_blk_1([#b_set{op=bs_start_match}=I|Is], FirstNumber,
- Aliases0, Acc0) ->
+ live_interval_blk_1(Is, FirstNumber, Acc);
+live_interval_blk_1([#b_set{op=bs_start_match}=I|Is],
+ FirstNumber, Acc0) ->
N = beam_ssa:get_anno(n, I),
#b_set{dst=Dst} = I,
Acc1 = [{Dst,{def,N}}|Acc0],
- Aliases = case beam_ssa:get_anno(reuse_for_context, I) of
- true ->
- #b_set{args=[Src]} = I,
- [{Dst,Src}|Aliases0];
- false ->
- Aliases0
- end,
Acc = [{V,{use,N}} || V <- beam_ssa:used(I)] ++ Acc1,
- live_interval_blk_1(Is, FirstNumber, Aliases, Acc);
-live_interval_blk_1([I|Is], FirstNumber, Aliases, Acc0) ->
+ live_interval_blk_1(Is, FirstNumber, Acc);
+live_interval_blk_1([I|Is], FirstNumber, Acc0) ->
N = beam_ssa:get_anno(n, I),
Acc1 = case I of
#b_set{dst=Dst} ->
@@ -1601,9 +1670,9 @@ live_interval_blk_1([I|Is], FirstNumber, Aliases, Acc0) ->
end,
Used = beam_ssa:used(I),
Acc = [{V,{use,N}} || V <- Used] ++ Acc1,
- live_interval_blk_1(Is, FirstNumber, Aliases, Acc);
-live_interval_blk_1([], _FirstNumber, Aliases, Acc) ->
- {Acc,Aliases}.
+ live_interval_blk_1(Is, FirstNumber, Acc);
+live_interval_blk_1([], _FirstNumber, Acc) ->
+ Acc.
%% first_number([#b_set{}]) -> InstructionNumber.
%% Return the number for the first instruction for the block.
@@ -1865,10 +1934,10 @@ reserve_zreg([#b_set{op={bif,tuple_size},dst=Dst}],
reserve_zreg_1(Dst, ShortLived, A);
reserve_zreg([#b_set{op=Op,dst=Dst}|Is], Last, ShortLived, A0) ->
IsZReg = case Op of
- context_to_binary -> true;
bs_match_string -> true;
- bs_restore -> true;
bs_save -> true;
+ bs_restore -> true;
+ bs_set_position -> true;
{float,clearerror} -> true;
kill_try_tag -> true;
landingpad -> true;
@@ -2040,82 +2109,6 @@ res_xregs_prune(Xs, Used, Res) ->
maps:filter(fun(_, {x,X}) -> X < NumSafe end, Xs).
%%%
-%%% Remove unsuitable aliases.
-%%%
-%%% If a binary is matched more than once, we must not put the
-%%% the match context in the same register as the binary to
-%%% avoid the following situation:
-%%%
-%%% {test,bs_start_match2,{f,3},1,[{x,0},0],{x,0}}.
-%%% .
-%%% .
-%%% .
-%%% {test,bs_start_match2,{f,6},1,[{x,0},0],{x,1}}. %% ILLEGAL!
-%%%
-%%% The second instruction is illegal because a match context source
-%%% is only allowed if source and destination registers are identical.
-%%%
-
-remove_unsuitable_aliases(#st{aliases=[_|_]=Aliases0,ssa=Blocks}=St) ->
- R = rem_unsuitable(maps:values(Blocks)),
- Unsuitable0 = [V || {V,[_,_|_]} <- rel2fam(R)],
- Unsuitable = gb_sets:from_list(Unsuitable0),
- Aliases =[P || {_,V}=P <- Aliases0,
- not gb_sets:is_member(V, Unsuitable)],
- St#st{aliases=Aliases};
-remove_unsuitable_aliases(#st{aliases=[]}=St) -> St.
-
-rem_unsuitable([#b_blk{is=Is}|Bs]) ->
- Vs = [{Var,Dst} ||
- #b_set{op=bs_start_match,dst=Dst,
- args=[#b_var{}=Var]} <- Is],
- Vs ++ rem_unsuitable(Bs);
-rem_unsuitable([]) -> [].
-
-%%%
-%%% Merge intervals.
-%%%
-
-merge_intervals(#st{aliases=Aliases0,intervals=Intervals0,
- res=Reserved}=St) ->
- Aliases1 = [A || A <- Aliases0,
- is_suitable_alias(A, Reserved)],
- case Aliases1 of
- [] ->
- St#st{aliases=Aliases1};
- [_|_] ->
- Intervals1 = maps:from_list(Intervals0),
- {Intervals,Aliases} =
- merge_intervals_1(Aliases1, Intervals1, []),
- St#st{aliases=Aliases,intervals=Intervals}
- end.
-
-merge_intervals_1([{Alias,V}|Vs], Intervals0, Acc) ->
- #{Alias:=Int1,V:=Int2} = Intervals0,
- Int3 = lists:merge(Int1, Int2),
- Int = merge_intervals_2(Int3),
- Intervals1 = maps:remove(Alias, Intervals0),
- Intervals = Intervals1#{V:=Int},
- merge_intervals_1(Vs, Intervals, [{Alias,V}|Acc]);
-merge_intervals_1([], Intervals, Acc) ->
- {maps:to_list(Intervals),Acc}.
-
-merge_intervals_2([{A1,B1},{A2,B2}|Is]) when A2 =< B1 ->
- merge_intervals_2([{min(A1, A2),max(B1, B2)}|Is]);
-merge_intervals_2([{_A1,B1}=R|[{A2,_B2}|_]=Is]) when B1 < A2 ->
- [R|merge_intervals_2(Is)];
-merge_intervals_2([_]=Is) -> Is.
-
-is_suitable_alias({V1,V2}, Reserved) ->
- #{V1:=Res1,V2:=Res2} = Reserved,
- case {Res1,Res2} of
- {x,x} -> true;
- {x,{x,_}} -> true;
- {{x,_},x} -> true;
- {_,_} -> false
- end.
-
-%%%
%%% Register allocation using linear scan.
%%%
diff --git a/lib/compiler/src/beam_ssa_type.erl b/lib/compiler/src/beam_ssa_type.erl
index 5ccc9c371b..18e6e73a46 100644
--- a/lib/compiler/src/beam_ssa_type.erl
+++ b/lib/compiler/src/beam_ssa_type.erl
@@ -486,6 +486,8 @@ type(bs_extract, [Ctx], Ts, _Ds) ->
Type;
type(bs_match, Args, _Ts, _Ds) ->
#t_bs_match{type=bs_match_type(Args)};
+type(bs_get_tail, _Args, _Ts, _Ds) ->
+ {binary, 1};
type(call, [#b_remote{mod=#b_literal{val=Mod},
name=#b_literal{val=Name}}|Args], Ts, _Ds) ->
case {Mod,Name,Args} of
diff --git a/lib/compiler/src/beam_utils.erl b/lib/compiler/src/beam_utils.erl
index 686d314c2d..626e041ea0 100644
--- a/lib/compiler/src/beam_utils.erl
+++ b/lib/compiler/src/beam_utils.erl
@@ -458,11 +458,6 @@ check_liveness(R, [{get_tuple_element,S,_,D}|Is], St) ->
D -> {killed,St};
_ -> check_liveness(R, Is, St)
end;
-check_liveness(R, [{bs_context_to_binary,S}|Is], St) ->
- case R of
- S -> {used,St};
- _ -> check_liveness(R, Is, St)
- end;
check_liveness(R, [{loop_rec,{f,_},{x,0}}|_], St) ->
case R of
{x,_} ->
diff --git a/lib/compiler/src/beam_validator.erl b/lib/compiler/src/beam_validator.erl
index e76b097500..ca065295d6 100644
--- a/lib/compiler/src/beam_validator.erl
+++ b/lib/compiler/src/beam_validator.erl
@@ -90,33 +90,30 @@ format_error(Error) ->
%% format as used in the compiler and in .S files.
validate(Module, Fs) ->
- Ft = index_bs_start_match(Fs, []),
+ Ft = index_parameter_types(Fs, []),
validate_0(Module, Fs, Ft).
-index_bs_start_match([{function,_,_,Entry,Code0}|Fs], Acc0) ->
+index_parameter_types([{function,_,_,Entry,Code0}|Fs], Acc0) ->
Code = dropwhile(fun({label,L}) when L =:= Entry -> false;
(_) -> true
end, Code0),
case Code of
[{label,Entry}|Is] ->
- Acc = index_bs_start_match_1(Is, Entry, Acc0),
- index_bs_start_match(Fs, Acc);
+ Acc = index_parameter_types_1(Is, Entry, Acc0),
+ index_parameter_types(Fs, Acc);
_ ->
%% Something serious is wrong. Ignore it for now.
%% It will be detected and diagnosed later.
- index_bs_start_match(Fs, Acc0)
+ index_parameter_types(Fs, Acc0)
end;
-index_bs_start_match([], Acc) ->
+index_parameter_types([], Acc) ->
gb_trees:from_orddict(lists:sort(Acc)).
-index_bs_start_match_1([{test,bs_start_match2,_,_,_,_}=I|_], Entry, Acc) ->
- [{Entry,[I]}|Acc];
-index_bs_start_match_1([{test,_,{f,F},_},{bs_context_to_binary,_}|Is0], Entry, Acc) ->
- [{label,F}|Is] = dropwhile(fun({label,L}) when L =:= F -> false;
- (_) -> true
- end, Is0),
- index_bs_start_match_1(Is, Entry, Acc);
-index_bs_start_match_1(_, _, Acc) -> Acc.
+index_parameter_types_1([{'%', {type_info, Reg, Type}} | Is], Entry, Acc) ->
+ Key = {Entry, Reg},
+ index_parameter_types_1(Is, Entry, [{Key, Type} | Acc]);
+index_parameter_types_1(_, _, Acc) ->
+ Acc.
validate_0(_Module, [], _) -> [];
validate_0(Module, [{function,Name,Ar,Entry,Code}|Fs], Ft) ->
@@ -289,17 +286,21 @@ valfun_1({try_case_end,Src}, Vst) ->
assert_term(Src, Vst),
kill_state(Vst);
%% Instructions that cannot cause exceptions
-valfun_1({bs_context_to_binary,Ctx}, #vst{current=#st{x=Xs}}=Vst) ->
- case Ctx of
- {Tag,X} when Tag =:= x; Tag =:= y ->
- Type = case gb_trees:lookup(X, Xs) of
- {value,#ms{}} -> term;
- _ -> get_term_type(Ctx, Vst)
- end,
- set_type_reg(Type, Ctx, Vst);
- _ ->
- error({bad_source,Ctx})
- end;
+valfun_1({bs_get_tail,Ctx,Dst,Live}, Vst0) ->
+ verify_live(Live, Vst0),
+ verify_y_init(Vst0),
+ Vst = prune_x_regs(Live, Vst0),
+ #vst{current=#st{x=Xs,y=Ys}} = Vst,
+ {Reg, Tree} = case Ctx of
+ {x,X} -> {X, Xs};
+ {y,Y} -> {Y, Ys};
+ _ -> error({bad_source,Ctx})
+ end,
+ Type = case gb_trees:lookup(Reg, Tree) of
+ {value,#ms{}} -> propagate_fragility(term, [Ctx], Vst);
+ _ -> error({bad_context,Reg})
+ end,
+ set_type_reg(Type, Dst, Vst);
valfun_1(bs_init_writable=I, Vst) ->
call(I, 1, Vst);
valfun_1(build_stacktrace=I, Vst) ->
@@ -385,6 +386,25 @@ valfun_1(remove_message, Vst) ->
%% The message term is no longer fragile. It can be used
%% without restrictions.
remove_fragility(Vst);
+valfun_1({'%', {type_info, Reg, Info0}}, Vst0) ->
+ %% Explicit type information inserted by optimization passes to indicate
+ %% that Reg has a certain type, so that we can accept cross-function type
+ %% optimizations.
+ %%
+ %% At the moment we only allow this when narrowing from 'term' which is
+ %% what to expect with function parameters, but in theory any narrowing
+ %% conversion should be legal.
+ case get_move_term_type(Reg, Vst0) of
+ term ->
+ Type0 = case Info0 of
+ match_context -> #ms{};
+ _ -> Info0
+ end,
+ Type = propagate_fragility(Type0, [Reg], Vst0),
+ set_type_reg(Type, Reg, Vst0);
+ _ ->
+ error(bad_type_info)
+ end;
valfun_1({'%',_}, Vst) ->
Vst;
valfun_1({line,_}, Vst) ->
@@ -676,32 +696,44 @@ valfun_4({select_tuple_arity,Tuple,{f,Fail},{list,Choices}}, Vst) ->
branch_state(Fail, Vst)));
%% New bit syntax matching instructions.
-valfun_4({test,bs_start_match2,{f,Fail},Live,[Ctx,NeedSlots],Ctx}, Vst0) ->
- %% If source and destination registers are the same, match state
- %% is OK as input.
- CtxType = get_move_term_type(Ctx, Vst0),
+valfun_4({test,bs_start_match3,{f,Fail},Live,[Src],Dst}, Vst0) ->
+ %% Match states are always okay as input.
+ SrcType = get_move_term_type(Src, Vst0),
+ DstType = propagate_fragility(bsm_match_state(), [Src], Vst0),
verify_live(Live, Vst0),
verify_y_init(Vst0),
Vst1 = prune_x_regs(Live, Vst0),
- BranchVst = case CtxType of
- #ms{} ->
- %% The failure branch will never be taken when Ctx
- %% is a match context. Therefore, the type for Ctx
- %% at the failure label must not be match_context
- %% (or we could reject legal code).
- set_type_reg(term, Ctx, Vst1);
- _ ->
- Vst1
- end,
+ BranchVst = case SrcType of
+ #ms{} ->
+ %% The failure branch will never be taken when Src is a
+ %% match context. Therefore, the type for Src at the
+ %% failure label must not be match_context (or we could
+ %% reject legal code).
+ set_type_reg(term, Src, Vst1);
+ _ ->
+ Vst1
+ end,
Vst = branch_state(Fail, BranchVst),
- set_type_reg(bsm_match_state(NeedSlots), Ctx, Vst);
+ set_type_reg(DstType, Dst, Vst);
valfun_4({test,bs_start_match2,{f,Fail},Live,[Src,Slots],Dst}, Vst0) ->
- assert_term(Src, Vst0),
+ %% Match states are always okay as input.
+ SrcType = get_move_term_type(Src, Vst0),
+ DstType = propagate_fragility(bsm_match_state(Slots), [Src], Vst0),
verify_live(Live, Vst0),
verify_y_init(Vst0),
Vst1 = prune_x_regs(Live, Vst0),
- Vst = branch_state(Fail, Vst1),
- set_type_reg(bsm_match_state(Slots), Src, Dst, Vst);
+ BranchVst = case SrcType of
+ #ms{} ->
+ %% The failure branch will never be taken when Src is a
+ %% match context. Therefore, the type for Src at the
+ %% failure label must not be match_context (or we could
+ %% reject legal code).
+ set_type_reg(term, Src, Vst1);
+ _ ->
+ Vst1
+ end,
+ Vst = branch_state(Fail, BranchVst),
+ set_type_reg(DstType, Dst, Vst);
valfun_4({test,bs_match_string,{f,Fail},[Ctx,_,_]}, Vst) ->
bsm_validate_context(Ctx, Vst),
branch_state(Fail, Vst);
@@ -738,6 +770,16 @@ valfun_4({bs_save2,Ctx,SavePoint}, Vst) ->
bsm_save(Ctx, SavePoint, Vst);
valfun_4({bs_restore2,Ctx,SavePoint}, Vst) ->
bsm_restore(Ctx, SavePoint, Vst);
+valfun_4({bs_get_position, Ctx, Dst, Live}, Vst0) ->
+ bsm_validate_context(Ctx, Vst0),
+ verify_live(Live, Vst0),
+ verify_y_init(Vst0),
+ Vst = prune_x_regs(Live, Vst0),
+ set_type_reg(bs_position, Dst, Vst);
+valfun_4({bs_set_position, Ctx, Pos}, Vst) ->
+ bsm_validate_context(Ctx, Vst),
+ assert_type(bs_position, Pos, Vst),
+ Vst;
%% Other test instructions.
valfun_4({test,is_float,{f,Lbl},[Float]}, Vst) ->
@@ -999,26 +1041,12 @@ verify_call_args_1(N, Vst) ->
verify_call_args_1(X, Vst).
verify_local_call(Lbl, Live, Vst) ->
- case all_ms_in_x_regs(Live, Vst) of
- [{R,Ctx}] ->
- %% Verify that there is a suitable bs_start_match2 instruction.
- verify_call_match_context(Lbl, R, Vst),
-
- %% Since the callee has consumed the match context,
- %% there must be no additional copies in Y registers.
- #ms{id=Id} = Ctx,
- case ms_in_y_regs(Id, Vst) of
- [] ->
- ok;
- [_|_]=Ys ->
- error({multiple_match_contexts,[R|Ys]})
- end;
- [_,_|_]=Xs0 ->
- Xs = [R || {R,_} <- Xs0],
- error({multiple_match_contexts,Xs});
- [] ->
- ok
- end.
+ F = fun({R, _Ctx}) ->
+ verify_call_match_context(Lbl, R, Vst)
+ end,
+ MsRegs = all_ms_in_x_regs(Live, Vst),
+ verify_no_ms_aliases(MsRegs),
+ foreach(F, MsRegs).
all_ms_in_x_regs(0, _Vst) ->
[];
@@ -1026,24 +1054,26 @@ all_ms_in_x_regs(Live0, Vst) ->
Live = Live0 - 1,
R = {x,Live},
case get_move_term_type(R, Vst) of
- #ms{}=M ->
- [{R,M}|all_ms_in_x_regs(Live, Vst)];
- _ ->
- all_ms_in_x_regs(Live, Vst)
+ #ms{}=M -> [{R,M} | all_ms_in_x_regs(Live, Vst)];
+ _ -> all_ms_in_x_regs(Live, Vst)
end.
-ms_in_y_regs(Id, #vst{current=#st{y=Ys0}}) ->
- Ys = gb_trees:to_list(Ys0),
- [{y,Y} || {Y,#ms{id=OtherId}} <- Ys, OtherId =:= Id].
+%% Verifies that the same match context isn't present twice.
+verify_no_ms_aliases(MsRegs) ->
+ CtxIds = [Id || {_, #ms{id=Id}} <- MsRegs],
+ UniqueCtxIds = ordsets:from_list(CtxIds),
+ if
+ length(UniqueCtxIds) < length(CtxIds) ->
+ error({multiple_match_contexts, MsRegs});
+ length(UniqueCtxIds) =:= length(CtxIds) ->
+ ok
+ end.
+%% Verifies that the target label accepts match contexts in the given register.
verify_call_match_context(Lbl, Ctx, #vst{ft=Ft}) ->
- case gb_trees:lookup(Lbl, Ft) of
- none ->
- error(no_bs_start_match2);
- {value,[{test,bs_start_match2,_,_,[Ctx,_],Ctx}|_]} ->
- ok;
- {value,[{test,bs_start_match2,_,_,_,_}=I|_]} ->
- error({unsuitable_bs_start_match2,I})
+ case gb_trees:lookup({Lbl, Ctx}, Ft) of
+ {value, match_context} -> ok;
+ none -> error(no_bs_start_match2)
end.
allocate(Zero, Stk, Heap, Live, #vst{current=#st{numy=none}}=Vst0) ->
@@ -1212,6 +1242,8 @@ assert_unique_map_keys([_,_|_]=Ls) ->
%%% New binary matching instructions.
%%%
+bsm_match_state() ->
+ #ms{}.
bsm_match_state(Slots) ->
#ms{slots=Slots}.
@@ -1225,6 +1257,12 @@ bsm_get_context({x,X}=Reg, #vst{current=#st{x=Xs}}=_Vst) when is_integer(X) ->
{value,{fragile,#ms{}=Ctx}} -> Ctx;
_ -> error({no_bsm_context,Reg})
end;
+bsm_get_context({y,Y}=Reg, #vst{current=#st{y=Ys}}=_Vst) when is_integer(Y) ->
+ case gb_trees:lookup(Y, Ys) of
+ {value,#ms{}=Ctx} -> Ctx;
+ {value,{fragile,#ms{}=Ctx}} -> Ctx;
+ _ -> error({no_bsm_context,Reg})
+ end;
bsm_get_context(Reg, _) -> error({bad_source,Reg}).
bsm_save(Reg, {atom,start}, Vst) ->
@@ -1255,6 +1293,7 @@ bsm_restore(Reg, SavePoint, Vst) ->
_ -> error({illegal_restore,SavePoint,range})
end.
+
select_val_branches(Src, Choices, Vst) ->
Infer = infer_types(Src, Vst),
select_val_branches_1(Choices, Infer, Vst).
diff --git a/lib/compiler/src/compile.erl b/lib/compiler/src/compile.erl
index 74ad864163..d894694c79 100644
--- a/lib/compiler/src/compile.erl
+++ b/lib/compiler/src/compile.erl
@@ -248,6 +248,9 @@ expand_opt(report, Os) ->
[report_errors,report_warnings|Os];
expand_opt(return, Os) ->
[return_errors,return_warnings|Os];
+expand_opt(no_bsm3, Os) ->
+ %% The new bsm pass requires bsm3 instructions.
+ [no_bsm3,no_bsm_opt|Os];
expand_opt(r16, Os) ->
expand_opt_before_21(Os);
expand_opt(r17, Os) ->
@@ -259,13 +262,14 @@ expand_opt(r19, Os) ->
expand_opt(r20, Os) ->
expand_opt_before_21(Os);
expand_opt(r21, Os) ->
- [no_put_tuple2|Os];
+ [no_put_tuple2 | expand_opt(no_bsm3, Os)];
expand_opt({debug_info_key,_}=O, Os) ->
[encrypt_debug_info,O|Os];
expand_opt(O, Os) -> [O|Os].
expand_opt_before_21(Os) ->
- [no_put_tuple2,no_get_hd_tl,no_ssa_opt_record,no_utf8_atoms|Os].
+ [no_put_tuple2, no_get_hd_tl, no_ssa_opt_record,
+ no_utf8_atoms | expand_opt(no_bsm3, Os)].
%% format_error(ErrorDescriptor) -> string()
@@ -816,6 +820,9 @@ kernel_passes() ->
{pass,beam_kernel_to_ssa},
{iff,dssa,{listing,"ssa"}},
{iff,ssalint,{pass,beam_ssa_lint}},
+ {unless,no_bsm_opt,{pass,beam_ssa_bsm}},
+ {iff,dssabsm,{listing,"ssabsm"}},
+ {iff,ssalint,{pass,beam_ssa_lint}},
{unless,no_ssa_opt,{pass,beam_ssa_opt}},
{iff,dssaopt,{listing,"ssaopt"}},
{iff,ssalint,{pass,beam_ssa_lint}},
@@ -847,8 +854,6 @@ asm_passes() ->
{iff,dpeep,{listing,"peep"}},
{pass,beam_clean},
{iff,dclean,{listing,"clean"}},
- {unless,no_bsm_opt,{pass,beam_bsm}},
- {iff,dbsm,{listing,"bsm"}},
{unless,no_stack_trimming,{pass,beam_trim}},
{iff,dtrim,{listing,"trim"}},
{pass,beam_flatten}]},
@@ -2030,7 +2035,6 @@ pre_load() ->
beam_asm,
beam_block,
beam_bs,
- beam_bsm,
beam_clean,
beam_dict,
beam_except,
@@ -2040,6 +2044,7 @@ pre_load() ->
beam_opcodes,
beam_peep,
beam_ssa,
+ beam_ssa_bsm,
beam_ssa_codegen,
beam_ssa_dead,
beam_ssa_opt,
diff --git a/lib/compiler/src/compiler.app.src b/lib/compiler/src/compiler.app.src
index bb281376ef..7b802fdd62 100644
--- a/lib/compiler/src/compiler.app.src
+++ b/lib/compiler/src/compiler.app.src
@@ -25,7 +25,6 @@
beam_asm,
beam_block,
beam_bs,
- beam_bsm,
beam_clean,
beam_dict,
beam_disasm,
@@ -37,6 +36,7 @@
beam_opcodes,
beam_peep,
beam_ssa,
+ beam_ssa_bsm,
beam_ssa_codegen,
beam_ssa_dead,
beam_ssa_lint,
diff --git a/lib/compiler/src/genop.tab b/lib/compiler/src/genop.tab
index 8e34e3e291..86590fad87 100755
--- a/lib/compiler/src/genop.tab
+++ b/lib/compiler/src/genop.tab
@@ -574,7 +574,25 @@ BEAM_FORMAT_NUMBER=0
## put it into the register Tail.
163: get_tl/2
+# OTP 22
+
## @spec put_tuple2 Destination Elements
## @doc Build a tuple with the elements in the list Elements and put it
## put into register Destination.
164: put_tuple2/2
+
+## @spec bs_get_tail Ctx Dst Live
+## @doc Sets Dst to the tail of Ctx at the current position
+165: bs_get_tail/3
+
+## @spec bs_start_match3 Fail Bin Live Dst
+## @doc Starts a binary match sequence
+166: bs_start_match3/4
+
+## @spec bs_get_position Ctx Dst Live
+## @doc Sets Dst to the current position of Ctx
+167: bs_get_position/3
+
+## @spec bs_set_positon Ctx Pos
+## @doc Sets the current position of Ctx to Pos
+168: bs_set_position/2
diff --git a/lib/compiler/src/sys_core_bsm.erl b/lib/compiler/src/sys_core_bsm.erl
index d7b26c3a56..685e807e65 100644
--- a/lib/compiler/src/sys_core_bsm.erl
+++ b/lib/compiler/src/sys_core_bsm.erl
@@ -24,161 +24,52 @@
-export([module/2,format_error/1]).
-include("core_parse.hrl").
--import(lists, [member/2,reverse/1,usort/1]).
-spec module(cerl:c_module(), [compile:option()]) -> {'ok', cerl:c_module()}.
-module(#c_module{defs=Ds0}=Mod, Opts) ->
- {Ds,Ws0} = function(Ds0, [], []),
- case member(bin_opt_info, Opts) of
- false ->
- {ok,Mod#c_module{defs=Ds}};
- true ->
- Ws1 = [make_warning(Where, What) || {Where,What} <- Ws0],
- Ws = usort(Ws1),
- {ok,Mod#c_module{defs=Ds},Ws}
- end.
+module(#c_module{defs=Ds}=Mod, _Opts) ->
+ {ok,Mod#c_module{defs=function(Ds)}}.
-function([{#c_var{name={F,Arity}}=Name,B0}|Fs], FsAcc, Ws0) ->
- try cerl_trees:mapfold(fun bsm_an/2, Ws0, B0) of
- {B,Ws} ->
- function(Fs, [{Name,B}|FsAcc], Ws)
+function([{#c_var{name={F,Arity}}=Name,B0}|Fs]) ->
+ try cerl_trees:map(fun bsm_reorder/1, B0) of
+ B -> [{Name,B} | function(Fs)]
catch
Class:Error:Stack ->
- io:fwrite("Function: ~w/~w\n", [F,Arity]),
- erlang:raise(Class, Error, Stack)
+ io:fwrite("Function: ~w/~w\n", [F,Arity]),
+ erlang:raise(Class, Error, Stack)
end;
-function([], Fs, Ws) ->
- {reverse(Fs),Ws}.
+function([]) ->
+ [].
-type error() :: atom().
-spec format_error(error()) -> nonempty_string().
-format_error(bin_opt_alias) ->
- "INFO: the '=' operator will prevent delayed sub binary optimization";
-format_error(bin_partition) ->
- "INFO: matching non-variables after a previous clause matching a variable "
- "will prevent delayed sub binary optimization";
-format_error(bin_var_used) ->
- "INFO: using a matched out sub binary will prevent "
- "delayed sub binary optimization";
-format_error(orig_bin_var_used_in_guard) ->
- "INFO: using the original binary variable in a guard will prevent "
- "delayed sub binary optimization";
-format_error(bin_var_used_in_guard) ->
- "INFO: using a matched out sub binary in a guard will prevent "
- "delayed sub binary optimization".
-
+format_error(_) -> error(badarg).
-%%%
-%%% Annotate bit syntax matching to faciliate optimization in further passes.
-%%%
+%%% Reorder bit syntax matching to faciliate optimization in further passes.
-bsm_an(Core0, Ws0) ->
- case bsm_an(Core0) of
- {ok,Core} ->
- {Core,Ws0};
- {ok,Core,W} ->
- {Core,[W|Ws0]}
- end.
+bsm_reorder(#c_case{arg=#c_var{}=V}=Case) ->
+ bsm_reorder_1([V], Case);
+bsm_reorder(#c_case{arg=#c_values{es=Es}}=Case) ->
+ bsm_reorder_1(Es, Case);
+bsm_reorder(Core) ->
+ Core.
-bsm_an(#c_case{arg=#c_var{}=V}=Case) ->
- bsm_an_1([V], Case);
-bsm_an(#c_case{arg=#c_values{es=Es}}=Case) ->
- bsm_an_1(Es, Case);
-bsm_an(Other) ->
- {ok,Other}.
-
-bsm_an_1(Vs0, #c_case{clauses=Cs0}=Case) ->
+bsm_reorder_1(Vs0, #c_case{clauses=Cs0}=Case) ->
case bsm_leftmost(Cs0) of
- none ->
- {ok,Case};
- 1 ->
- bsm_an_2(Vs0, Cs0, Case);
- Pos ->
- Vs = move_from_col(Pos, Vs0),
- Cs = [C#c_clause{pats=move_from_col(Pos, Ps)} ||
- #c_clause{pats=Ps}=C <- Cs0],
- bsm_an_2(Vs, Cs, Case)
- end.
-
-bsm_an_2(Vs, Cs, Case) ->
- try
- bsm_ensure_no_partition(Cs),
- {ok,bsm_do_an(Vs, Cs, Case)}
- catch
- throw:{problem,Where,What} ->
- {ok,Case,{Where,What}}
+ Pos when Pos > 0, Pos =/= none ->
+ Vs = core_lib:make_values(move_from_col(Pos, Vs0)),
+ Cs = [C#c_clause{pats=move_from_col(Pos, Ps)}
+ || #c_clause{pats=Ps}=C <- Cs0],
+ Case#c_case{arg=Vs,clauses=Cs};
+ _ ->
+ Case
end.
move_from_col(Pos, L) ->
{First,[Col|Rest]} = lists:split(Pos - 1, L),
[Col|First] ++ Rest.
-bsm_do_an([#c_var{name=Vname}=V0|Vs0], Cs0, Case) ->
- Cs = bsm_do_an_var(Vname, Cs0),
- V = bsm_annotate_for_reuse(V0),
- Vs = core_lib:make_values([V|Vs0]),
- Case#c_case{arg=Vs,clauses=Cs};
-bsm_do_an(_Vs, _Cs, Case) -> Case.
-
-bsm_do_an_var(V, [#c_clause{pats=[P|_],guard=G,body=B0}=C0|Cs]) ->
- case P of
- #c_var{name=VarName} ->
- case core_lib:is_var_used(V, G) of
- true -> bsm_problem(C0, orig_bin_var_used_in_guard);
- false -> ok
- end,
- case core_lib:is_var_used(VarName, G) of
- true -> bsm_problem(C0, bin_var_used_in_guard);
- false -> ok
- end,
- B1 = bsm_maybe_ctx_to_binary(VarName, B0),
- B = bsm_maybe_ctx_to_binary(V, B1),
- C = C0#c_clause{body=B},
- [C|bsm_do_an_var(V, Cs)];
- #c_alias{} ->
- case bsm_could_match_binary(P) of
- false ->
- [C0|bsm_do_an_var(V, Cs)];
- true ->
- bsm_problem(C0, bin_opt_alias)
- end;
- _ ->
- case bsm_could_match_binary(P) andalso bsm_is_var_used(V, G, B0) of
- false ->
- [C0|bsm_do_an_var(V, Cs)];
- true ->
- bsm_problem(C0, bin_var_used)
- end
- end;
-bsm_do_an_var(_, []) -> [].
-
-bsm_annotate_for_reuse(#c_var{anno=Anno}=Var) ->
- Var#c_var{anno=[reuse_for_context|Anno]}.
-
-bsm_is_var_used(V, G, B) ->
- core_lib:is_var_used(V, G) orelse core_lib:is_var_used(V, B).
-
-bsm_maybe_ctx_to_binary(V, B) ->
- case core_lib:is_var_used(V, B) andalso not previous_ctx_to_binary(V, B) of
- false ->
- B;
- true ->
- #c_seq{arg=#c_primop{name=#c_literal{val=bs_context_to_binary},
- args=[#c_var{name=V}]},
- body=B}
- end.
-
-previous_ctx_to_binary(V, Core) ->
- case Core of
- #c_seq{arg=#c_primop{name=#c_literal{val=bs_context_to_binary},
- args=[#c_var{name=V}]}} ->
- true;
- _ ->
- false
- end.
-
%% bsm_leftmost(Cs) -> none | ArgumentNumber
%% Find the leftmost argument that matches a nonempty binary.
%% Return either 'none' or the argument number (1-N).
@@ -200,94 +91,3 @@ bsm_leftmost_2([_|Ps], Cs, N, Pos) ->
bsm_leftmost_2(Ps, Cs, N+1, Pos);
bsm_leftmost_2([], Cs, _, Pos) ->
bsm_leftmost_1(Cs, Pos).
-
-%% bsm_ensure_no_partition(Cs) -> ok (exception if problem)
-%% There must only be a single bs_start_match2 instruction if we
-%% are to reuse the binary variable for the match context.
-%%
-%% To make sure that there is only a single bs_start_match2
-%% instruction, we will check for partitions such as:
-%%
-%% foo(<<...>>) -> ...
-%% foo(<Variable>) when ... -> ...
-%% foo(<Non-variable pattern>) ->
-%%
-%% If there is such partition, we reject the optimization.
-
-bsm_ensure_no_partition(Cs) ->
- bsm_ensure_no_partition_1(Cs, before).
-
-%% Loop through each clause.
-bsm_ensure_no_partition_1([#c_clause{pats=Ps,guard=G}|Cs], State0) ->
- State = bsm_ensure_no_partition_2(Ps, G, State0),
- case State of
- 'after' ->
- bsm_ensure_no_partition_after(Cs);
- _ ->
- ok
- end,
- bsm_ensure_no_partition_1(Cs, State);
-bsm_ensure_no_partition_1([], _) -> ok.
-
-bsm_ensure_no_partition_2([#c_binary{}|_], _, _State) ->
- within;
-bsm_ensure_no_partition_2([#c_alias{}=Alias|_], N, State) ->
- %% Retrieve the real pattern that the alias refers to and check that.
- P = bsm_real_pattern(Alias),
- bsm_ensure_no_partition_2([P], N, State);
-bsm_ensure_no_partition_2([_|_], _, before=State) ->
- %% No binary matching yet - therefore no partition.
- State;
-bsm_ensure_no_partition_2([P|_], _, State) ->
- case bsm_could_match_binary(P) of
- false ->
- State;
- true ->
- %% The pattern P *may* match a binary, so we must update the state.
- %% (P must be a variable.)
- 'after'
- end.
-
-bsm_ensure_no_partition_after([#c_clause{pats=Ps}=C|Cs]) ->
- case Ps of
- [#c_var{}|_] ->
- bsm_ensure_no_partition_after(Cs);
- _ ->
- bsm_problem(C, bin_partition)
- end;
-bsm_ensure_no_partition_after([]) -> ok.
-
-bsm_could_match_binary(#c_alias{pat=P}) -> bsm_could_match_binary(P);
-bsm_could_match_binary(#c_cons{}) -> false;
-bsm_could_match_binary(#c_tuple{}) -> false;
-bsm_could_match_binary(#c_literal{val=Lit}) -> is_bitstring(Lit);
-bsm_could_match_binary(_) -> true.
-
-bsm_real_pattern(#c_alias{pat=P}) -> bsm_real_pattern(P);
-bsm_real_pattern(P) -> P.
-
-bsm_problem(Where, What) ->
- throw({problem,Where,What}).
-
-make_warning(Core, Term) ->
- case should_suppress_warning(Core) of
- true ->
- ok;
- false ->
- Anno = cerl:get_ann(Core),
- Line = get_line(Anno),
- File = get_file(Anno),
- {File,[{Line,?MODULE,Term}]}
- end.
-
-should_suppress_warning(Core) ->
- Ann = cerl:get_ann(Core),
- member(compiler_generated, Ann).
-
-get_line([Line|_]) when is_integer(Line) -> Line;
-get_line([_|T]) -> get_line(T);
-get_line([]) -> none.
-
-get_file([{file,File}|_]) -> File;
-get_file([_|T]) -> get_file(T);
-get_file([]) -> "no_file". % should not happen
diff --git a/lib/compiler/src/v3_kernel.erl b/lib/compiler/src/v3_kernel.erl
index fe8e252e5a..f7ca66b1da 100644
--- a/lib/compiler/src/v3_kernel.erl
+++ b/lib/compiler/src/v3_kernel.erl
@@ -82,8 +82,7 @@
-export([module/2,format_error/1]).
-import(lists, [map/2,foldl/3,foldr/3,mapfoldl/3,splitwith/2,member/2,
- keymember/3,keyfind/3,partition/2,droplast/1,last/1,sort/1,
- reverse/1]).
+ keyfind/3,partition/2,droplast/1,last/1,sort/1,reverse/1]).
-import(ordsets, [add_element/2,del_element/2,union/2,union/1,subtract/2]).
-import(cerl, [c_tuple/1]).
@@ -1416,7 +1415,6 @@ is_remote_bif(_, _, _) -> false.
%% called for effect only.
bif_vals(dsetelement, 3) -> 0;
-bif_vals(bs_context_to_binary, 1) -> 0;
bif_vals(_, _) -> 1.
bif_vals(_, _, _) -> 1.
@@ -2337,8 +2335,7 @@ uexpr(#k_bif{anno=A,op=Op,args=As}=Bif, {break,Rs}, St0) ->
{Brs,St1} = bif_returns(Op, Rs, St0),
{Bif#k_bif{anno=#k{us=Used,ns=lit_list_vars(Brs),a=A},ret=Brs},
Used,St1};
-uexpr(#k_match{anno=A,vars=Vs0,body=B0}, Br, St0) ->
- Vs = handle_reuse_annos(Vs0, St0),
+uexpr(#k_match{anno=A,vars=Vs,body=B0}, Br, St0) ->
Rs = break_rets(Br),
{B1,Bu,St1} = umatch(B0, Br, St0),
case is_in_guard(St1) of
@@ -2441,33 +2438,6 @@ make_fdef(Anno, Name, Arity, Vs, Body) ->
vars=Vs,body=Body,ret=[]},
#k_fdef{anno=Anno,func=Name,arity=Arity,vars=Vs,body=Match}.
-
-%% handle_reuse_annos([#k_var{}], State) -> State.
-%% In general, it is only safe to reuse a variable for a match context
-%% if the original value of the variable will no longer be needed.
-%%
-%% If a variable has been bound in an outer letrec and is therefore
-%% free in the current function, the variable may still be used.
-%% We don't bother to check whether the variable is actually used,
-%% but simply clears the 'reuse_for_context' annotation for any variable
-%% that is free.
-handle_reuse_annos(Vs, St) ->
- [handle_reuse_anno(V, St) || V <- Vs].
-
-handle_reuse_anno(#k_var{anno=A}=V, St) ->
- case member(reuse_for_context, A) of
- false -> V;
- true -> handle_reuse_anno_1(V, St)
- end.
-
-handle_reuse_anno_1(#k_var{anno=Anno,name=Vname}=V, #kern{ff={F,A}}=St) ->
- FreeVs = get_free(F, A, St),
- case keymember(Vname, #k_var.name, FreeVs) of
- true -> V#k_var{anno=Anno--[reuse_for_context]};
- false -> V
- end;
-handle_reuse_anno_1(V, _St) -> V.
-
%% get_free(Name, Arity, State) -> [Free].
%% store_free(Name, Arity, [Free], State) -> State.
@@ -2511,8 +2481,7 @@ umatch(#k_alt{anno=A,first=F0,then=T0}, Br, St0) ->
Used = union(Fu, Tu),
{#k_alt{anno=#k{us=Used,ns=[],a=A},first=F1,then=T1},
Used,St2};
-umatch(#k_select{anno=A,var=V0,types=Ts0}, Br, St0) ->
- V = handle_reuse_anno(V0, St0),
+umatch(#k_select{anno=A,var=V,types=Ts0}, Br, St0) ->
{Ts1,Tus,St1} = umatch_list(Ts0, Br, St0),
Used = case member(no_usage, get_kanno(V)) of
true -> Tus;
diff --git a/lib/compiler/test/Makefile b/lib/compiler/test/Makefile
index 2a5004aa4c..e56594f344 100644
--- a/lib/compiler/test/Makefile
+++ b/lib/compiler/test/Makefile
@@ -97,6 +97,9 @@ INLINE= \
receive \
record
+R21= \
+ bs_match
+
CORE_MODULES = \
lfe_andor_SUITE \
lfe_guard_SUITE
@@ -107,6 +110,8 @@ POST_OPT_MODULES= $(NO_OPT:%=%_post_opt_SUITE)
POST_OPT_ERL_FILES= $(POST_OPT_MODULES:%=%.erl)
INLINE_MODULES= $(INLINE:%=%_inline_SUITE)
INLINE_ERL_FILES= $(INLINE_MODULES:%=%.erl)
+R21_MODULES= $(R21:%=%_r21_SUITE)
+R21_ERL_FILES= $(R21_MODULES:%=%.erl)
ERL_FILES= $(MODULES:%=%.erl)
CORE_FILES= $(CORE_MODULES:%=%.core)
@@ -135,7 +140,8 @@ EBIN = .
# Targets
# ----------------------------------------------------
-make_emakefile: $(NO_OPT_ERL_FILES) $(POST_OPT_ERL_FILES) $(INLINE_ERL_FILES)
+make_emakefile: $(NO_OPT_ERL_FILES) $(POST_OPT_ERL_FILES) \
+ $(INLINE_ERL_FILES) $(R21_ERL_FILES)
$(ERL_TOP)/make/make_emakefile $(ERL_COMPILE_FLAGS) -o$(EBIN) $(MODULES) \
> $(EMAKEFILE)
$(ERL_TOP)/make/make_emakefile +no_copt +no_postopt \
@@ -145,6 +151,8 @@ make_emakefile: $(NO_OPT_ERL_FILES) $(POST_OPT_ERL_FILES) $(INLINE_ERL_FILES)
-o$(EBIN) $(POST_OPT_MODULES) >> $(EMAKEFILE)
$(ERL_TOP)/make/make_emakefile +inline $(ERL_COMPILE_FLAGS) \
-o$(EBIN) $(INLINE_MODULES) >> $(EMAKEFILE)
+ $(ERL_TOP)/make/make_emakefile +r21 $(ERL_COMPILE_FLAGS) \
+ -o$(EBIN) $(R21_MODULES) >> $(EMAKEFILE)
$(ERL_TOP)/make/make_emakefile +from_core $(ERL_COMPILE_FLAGS) \
-o$(EBIN) $(CORE_MODULES) >> $(EMAKEFILE)
@@ -171,6 +179,9 @@ docs:
%_inline_SUITE.erl: %_SUITE.erl
sed -e 's;-module($(basename $<));-module($(basename $@));' $< > $@
+%_r21_SUITE.erl: %_SUITE.erl
+ sed -e 's;-module($(basename $<));-module($(basename $@));' $< > $@
+
# ----------------------------------------------------
# Release Target
# ----------------------------------------------------
@@ -183,7 +194,7 @@ release_tests_spec: make_emakefile
$(INSTALL_DATA) compiler.spec compiler.cover \
$(EMAKEFILE) $(ERL_FILES) "$(RELSYSDIR)"
$(INSTALL_DATA) $(NO_OPT_ERL_FILES) $(POST_OPT_ERL_FILES) \
- $(INLINE_ERL_FILES) "$(RELSYSDIR)"
+ $(INLINE_ERL_FILES) $(R21_ERL_FILES) "$(RELSYSDIR)"
$(INSTALL_DATA) $(CORE_FILES) "$(RELSYSDIR)"
for file in $(ERL_DUMMY_FILES); do \
module=`basename $$file .erl`; \
diff --git a/lib/compiler/test/beam_validator_SUITE_data/bad_bin_match.S b/lib/compiler/test/beam_validator_SUITE_data/bad_bin_match.S
index a60ca1e89a..c7610971f1 100644
--- a/lib/compiler/test/beam_validator_SUITE_data/bad_bin_match.S
+++ b/lib/compiler/test/beam_validator_SUITE_data/bad_bin_match.S
@@ -11,5 +11,5 @@
{label,1}.
{func_info,{atom,t},{atom,t},1}.
{label,2}.
- {test,bs_start_match2,{f,1},1,[{x,0},0],{x,0}}.
+ {test,bs_start_match3,{f,1},1,[{x,0}],{x,0}}.
return.
diff --git a/lib/compiler/test/beam_validator_SUITE_data/receive_stacked.S b/lib/compiler/test/beam_validator_SUITE_data/receive_stacked.S
index cca052a9c4..5b974119c6 100644
--- a/lib/compiler/test/beam_validator_SUITE_data/receive_stacked.S
+++ b/lib/compiler/test/beam_validator_SUITE_data/receive_stacked.S
@@ -172,7 +172,7 @@
{allocate_zero,1,0}.
{label,28}.
{loop_rec,{f,30},{x,0}}.
- {test,bs_start_match2,{f,29},1,[{x,0},0],{x,0}}.
+ {test,bs_start_match3,{f,29},1,[{x,0}],{x,0}}.
{test,bs_get_integer2,
{f,29},
1,
@@ -219,7 +219,7 @@
{allocate_zero,1,0}.
{label,33}.
{loop_rec,{f,35},{x,0}}.
- {test,bs_start_match2,{f,34},1,[{x,0},0],{x,0}}.
+ {test,bs_start_match3,{f,34},1,[{x,0}],{x,0}}.
{test,bs_get_integer2,
{f,34},
1,
@@ -262,7 +262,7 @@
{allocate_zero,1,0}.
{label,38}.
{loop_rec,{f,40},{x,0}}.
- {test,bs_start_match2,{f,39},1,[{x,0},0],{x,1}}.
+ {test,bs_start_match3,{f,39},1,[{x,0}],{x,1}}.
{test,bs_get_integer2,
{f,39},
2,
diff --git a/lib/compiler/test/bs_match_SUITE.erl b/lib/compiler/test/bs_match_SUITE.erl
index b4277f0705..e654979a96 100644
--- a/lib/compiler/test/bs_match_SUITE.erl
+++ b/lib/compiler/test/bs_match_SUITE.erl
@@ -40,7 +40,9 @@
map_and_binary/1,unsafe_branch_caching/1,
bad_literals/1,good_literals/1,constant_propagation/1,
parse_xml/1,get_payload/1,escape/1,num_slots_different/1,
- beam_bsm/1,guard/1,is_ascii/1,non_opt_eq/1,erl_689/1]).
+ beam_bsm/1,guard/1,is_ascii/1,non_opt_eq/1,
+ expression_before_match/1,erl_689/1,restore_on_call/1,
+ restore_after_catch/1,matches_on_parameter/1,big_positions/1]).
-export([coverage_id/1,coverage_external_ignore/2]).
@@ -56,7 +58,7 @@ all() ->
[{group,p}].
groups() ->
- [{p,[parallel],
+ [{p,[],
[size_shadow,int_float,otp_5269,null_fields,wiger,
bin_tail,save_restore,
partitioned_bs_match,function_clause,unit,
@@ -72,7 +74,9 @@ groups() ->
map_and_binary,unsafe_branch_caching,
bad_literals,good_literals,constant_propagation,parse_xml,
get_payload,escape,num_slots_different,
- beam_bsm,guard,is_ascii,non_opt_eq,erl_689]}].
+ beam_bsm,guard,is_ascii,non_opt_eq,
+ expression_before_match,erl_689,restore_on_call,
+ matches_on_parameter,big_positions]}].
init_per_suite(Config) ->
@@ -1764,4 +1768,93 @@ do_erl_689_2(_, <<Length, Data/binary>>) ->
check(F, R) ->
R = F().
+%% Make sure that an expression that comes between function start and a match
+%% expression passes validation.
+expression_before_match(Config) when is_list(Config) ->
+ <<_,R/binary>> = id(<<0,1,2,3>>),
+ {1, <<2,3>>} = expression_before_match_1(R),
+ ok.
+
+expression_before_match_1(R) ->
+ A = id(1),
+ case R of
+ <<1,Bar/binary>> -> {A, Bar};
+ <<>> -> {A, baz}
+ end.
+
+%% Make sure that context positions are updated on calls.
+restore_on_call(Config) when is_list(Config) ->
+ ok = restore_on_call_1(<<0, 1, 2>>).
+
+restore_on_call_1(<<0, Rest/binary>>) ->
+ <<2>> = restore_on_call_2(Rest),
+ <<2>> = restore_on_call_2(Rest), %% {badmatch, <<>>} on missing restore.
+ ok.
+
+restore_on_call_2(<<1, Rest/binary>>) -> Rest;
+restore_on_call_2(Other) -> Other.
+
+%% 'catch' must invalidate positions.
+restore_after_catch(Config) when is_list(Config) ->
+ <<0, 1>> = restore_after_catch_1(<<0, 1>>),
+ ok.
+
+restore_after_catch_1(<<A/binary>>) ->
+ try throw_after_byte(A) of
+ _ -> impossible
+ catch
+ throw:_Any ->
+ %% Will equal <<1>> if the bug is present.
+ A
+ end.
+
+throw_after_byte(<<_,_/binary>>) ->
+ throw(away).
+
+matches_on_parameter(Config) when is_list(Config) ->
+ %% This improves coverage for matching on "naked" parameters.
+ {<<"urka">>, <<"a">>} = matches_on_parameter_1(<<"gurka">>),
+ ok = (catch matches_on_parameter_2(<<"10001110101">>, 0)).
+
+matches_on_parameter_1(Bin) ->
+ <<"g", A/binary>> = Bin,
+ <<_,_,"rk", B/binary>> = Bin,
+ {A, B}.
+
+matches_on_parameter_2(Bin, Offset) ->
+ <<_:Offset, Bit:1, Rest/bits>> = Bin,
+ case bit_size(Rest) of
+ 0 -> throw(ok);
+ _ -> [Bit | matches_on_parameter_2(Bin, Offset + 1)]
+ end.
+
+big_positions(Config) when is_list(Config) ->
+ %% This provides coverage for when match context positions no longer fit
+ %% into an immediate on 32-bit platforms.
+
+ A = <<0:((1 bsl 27) - 8), $A, 1:1, "gurka", $A>>,
+ B = <<0:((1 bsl 27) - 8), $B, "hello", $B>>,
+
+ {a,$A} = bp_start_match(A),
+ {b,$B} = bp_start_match(B),
+ {a,$A} = bp_getpos(A),
+ {b,$B} = bp_getpos(B),
+
+ ok.
+
+%% After the first iteration the context's position will no longer fit into an
+%% immediate. To improve performance the bs_start_match3 instruction will
+%% return a new context with an updated base position so that we won't have to
+%% resort to using bigints.
+bp_start_match(<<_:(1 bsl 27),T/bits>>) -> bp_start_match(T);
+bp_start_match(<<1:1,"gurka",A>>) -> {a,A};
+bp_start_match(<<"hello",B>>) -> {b,B}.
+
+%% This is a corner case where the above didn't work perfectly; if the position
+%% was _just_ small enough to fit into an immediate when bs_start_match3 was
+%% hit, but too large at bs_get_position, then it must be saved as a bigint.
+bp_getpos(<<_:((1 bsl 27) - 8),T/bits>>) -> bp_getpos(T);
+bp_getpos(<<A,1:1,"gurka",A>>) -> {a,A};
+bp_getpos(<<B,"hello",B>>) -> {b,B}.
+
id(I) -> I.
diff --git a/lib/compiler/test/compile_SUITE.erl b/lib/compiler/test/compile_SUITE.erl
index 38bc928f85..b79b4171d3 100644
--- a/lib/compiler/test/compile_SUITE.erl
+++ b/lib/compiler/test/compile_SUITE.erl
@@ -1481,7 +1481,10 @@ bc_options(Config) ->
132 = highest_opcode(DataDir, small,
[no_put_tuple2,no_get_hd_tl,no_ssa_opt_record,
- no_ssa_opt_float,no_line_info]),
+ no_ssa_opt_float,no_line_info,no_bsm3]),
+
+ 153 = highest_opcode(DataDir, small, [r20]),
+ 153 = highest_opcode(DataDir, small, [r21]),
136 = highest_opcode(DataDir, big, [no_put_tuple2,no_get_hd_tl,
no_ssa_opt_record,no_line_info]),
diff --git a/lib/compiler/test/misc_SUITE.erl b/lib/compiler/test/misc_SUITE.erl
index 4c2d0116c9..c9acda2b6d 100644
--- a/lib/compiler/test/misc_SUITE.erl
+++ b/lib/compiler/test/misc_SUITE.erl
@@ -254,17 +254,6 @@ silly_coverage(Config) when is_list(Config) ->
2},
expect_error(fun() -> beam_peep:module(PeepInput, []) end),
- %% beam_bsm. This is tricky. Our function must be sane enough to not crash
- %% btb_index/1, but must crash the main optimization pass.
- BsmInput = {?MODULE,[{foo,0}],[],
- [{function,foo,0,2,
- [{label,1},
- {func_info,{atom,?MODULE},{atom,foo},0},
- {label,2},
- {test,bs_get_binary2,{f,99},0,[{x,0},{atom,all},1,[]],{x,0}},
- {block,[a|b]}]}],0},
- expect_error(fun() -> beam_bsm:module(BsmInput, []) end),
-
BeamZInput = {?MODULE,[{foo,0}],[],
[{function,foo,0,2,
[{label,1},
diff --git a/lib/compiler/test/test_lib.erl b/lib/compiler/test/test_lib.erl
index c6baa611ec..4502f5b68a 100644
--- a/lib/compiler/test/test_lib.erl
+++ b/lib/compiler/test/test_lib.erl
@@ -78,6 +78,9 @@ opt_opts(Mod) ->
(no_stack_trimming) -> true;
(debug_info) -> true;
(inline) -> true;
+ (no_put_tuple2) -> true;
+ (no_bsm3) -> true;
+ (no_bsm_opt) -> true;
(_) -> false
end, Opts).
@@ -89,8 +92,9 @@ get_data_dir(Config) ->
Data0 = proplists:get_value(data_dir, Config),
Opts = [{return,list}],
Data1 = re:replace(Data0, "_no_opt_SUITE", "_SUITE", Opts),
- Data = re:replace(Data1, "_post_opt_SUITE", "_SUITE", Opts),
- re:replace(Data, "_inline_SUITE", "_SUITE", Opts).
+ Data2 = re:replace(Data1, "_post_opt_SUITE", "_SUITE", Opts),
+ Data = re:replace(Data2, "_inline_SUITE", "_SUITE", Opts),
+ re:replace(Data, "_r21_SUITE", "_SUITE", Opts).
is_cloned_mod(Mod) ->
is_cloned_mod_1(atom_to_list(Mod)).
@@ -100,6 +104,7 @@ is_cloned_mod(Mod) ->
is_cloned_mod_1("no_opt_SUITE") -> true;
is_cloned_mod_1("post_opt_SUITE") -> true;
is_cloned_mod_1("inline_SUITE") -> true;
+is_cloned_mod_1("21_SUITE") -> true;
is_cloned_mod_1([_|T]) -> is_cloned_mod_1(T);
is_cloned_mod_1([]) -> false.
diff --git a/lib/compiler/test/warnings_SUITE.erl b/lib/compiler/test/warnings_SUITE.erl
index 33d55996ad..1f39348998 100644
--- a/lib/compiler/test/warnings_SUITE.erl
+++ b/lib/compiler/test/warnings_SUITE.erl
@@ -522,25 +522,43 @@ bin_opt_info(Config) when is_list(Config) ->
<<>> -> ok
end.
+ %% We use a tail in a BIF instruction, remote call, function
+ %% return, and an optimizable tail call for better coverage.
+ t2(<<A,B,T/bytes>>) ->
+ if
+ A > B -> t2(T);
+ A =< B -> T
+ end;
+ t2(<<_,T/bytes>>) when byte_size(T) < 4 ->
+ foo;
t2(<<_,T/bytes>>) ->
- split_binary(T, 4).
+ split_binary(T, 4).
">>,
- Ts1 = [{bsm1,
- Code,
- [bin_opt_info],
- {warnings,
- [{4,sys_core_bsm,orig_bin_var_used_in_guard},
- {5,beam_bsm,{no_bin_opt,{{t1,1},no_suitable_bs_start_match}}},
- {9,beam_bsm,{no_bin_opt,
- {binary_used_in,{extfunc,erlang,split_binary,2}}}} ]}}],
- [] = run(Config, Ts1),
+
+ Ws = (catch run_test(Config, Code, [bin_opt_info])),
+
+ %% This is an inexact match since the pass reports exact instructions as
+ %% part of the warnings, which may include annotations that vary from run
+ %% to run.
+ {warnings,
+ [{5,beam_ssa_bsm,{unsuitable_call,
+ {{b_local,{b_literal,t1},1},
+ {used_before_match,
+ {b_set,_,_,{bif,byte_size},[_]}}}}},
+ {5,beam_ssa_bsm,{binary_created,_,_}},
+ {11,beam_ssa_bsm,{binary_created,_,_}}, %% A =< B -> T
+ {13,beam_ssa_bsm,context_reused}, %% A > B -> t2(T);
+ {16,beam_ssa_bsm,{binary_created,_,_}}, %% when byte_size(T) < 4 ->
+ {19,beam_ssa_bsm,{remote_call,
+ {b_remote,
+ {b_literal,erlang},
+ {b_literal,split_binary},2}}},
+ {19,beam_ssa_bsm,{binary_created,_,_}} %% split_binary(T, 4)
+ ]} = Ws,
%% For coverage: don't give the bin_opt_info option.
- Ts2 = [{bsm2,
- Code,
- [],
- []}],
- [] = run(Config, Ts2),
+ [] = (catch run_test(Config, Code, [])),
+
ok.
bin_construction(Config) when is_list(Config) ->
@@ -746,7 +764,7 @@ maps_bin_opt_info(Config) when is_list(Config) ->
M.
">>,
[bin_opt_info],
- {warnings,[{2,beam_bsm,bin_opt}]}}],
+ {warnings,[{3,beam_ssa_bsm,context_reused}]}}],
[] = run(Config, Ts),
ok.
@@ -969,7 +987,6 @@ run(Config, Tests) ->
end,
lists:foldl(F, [], Tests).
-
%% Compiles a test module and returns the list of errors and warnings.
run_test(Conf, Test0, Warnings) ->
diff --git a/lib/hipe/doc/src/hipe_app.xml b/lib/hipe/doc/src/hipe_app.xml
index 99759a2f2c..480290cd9e 100644
--- a/lib/hipe/doc/src/hipe_app.xml
+++ b/lib/hipe/doc/src/hipe_app.xml
@@ -62,6 +62,13 @@
and the runtime system that have limited or no support for HiPE compiled modules.
</p>
<taglist>
+ <tag>Binary matching</tag>
+ <item><p>The HiPE compiler will crash on modules containing binary
+ matching unless they have been compiled with the <c>+no_bsm3</c> flag.
+ Note that this will disable all related optimizations done by the BEAM
+ compiler.</p>
+ </item>
+
<tag>Stack traces</tag>
<item><p>Stack traces returned from <seealso marker="erts:erlang#get_stacktrace/0">
<c>erlang:get_stacktrace/0</c></seealso> or as part of <c>'EXIT'</c> terms
diff --git a/lib/hipe/test/Makefile b/lib/hipe/test/Makefile
index efeb0887ab..3650cda663 100644
--- a/lib/hipe/test/Makefile
+++ b/lib/hipe/test/Makefile
@@ -13,7 +13,6 @@ MODULES= \
# .erl files for these modules are automatically generated
GEN_MODULES= \
basic_SUITE \
- bs_SUITE \
maps_SUITE \
sanity_SUITE
diff --git a/lib/hipe/test/basic_SUITE_data/basic_inline_function.erl b/lib/hipe/test/basic_SUITE_data/basic_inline_function.erl
deleted file mode 100644
index 4c08064670..0000000000
--- a/lib/hipe/test/basic_SUITE_data/basic_inline_function.erl
+++ /dev/null
@@ -1,73 +0,0 @@
-%%% -*- erlang-indent-level: 2 -*-
-%%%-------------------------------------------------------------------
-%%% Author: Kostis Sagonas
-%%%
-%%% Contains tests that depend on the compiler inliner being turned on.
-%%%-------------------------------------------------------------------
--module(basic_inline_function).
-
--export([test/0]).
-
--compile({inline, [{to_objects, 3}]}).
-
-test() ->
- ok = test_inline_match(),
- ok.
-
-%%--------------------------------------------------------------------
-
-test_inline_match() ->
- bad_object = test1(a, {binary, foo, set}, c),
- bad_object = test2(a, {binary, foo, set}, c),
- bad_object = test3(a, {binary, foo, set}, c),
- ok.
-
-%% Inlined
-test1(KeysObjs, C, Ts) ->
- case catch to_objects(KeysObjs, C, Ts) of
- {'EXIT', _} ->
- bad_object;
- ok ->
- ok
- end.
-
-%% "Inlined" by hand
-test2(KeysObjs, C, _Ts) ->
- case catch (case C of
- {binary, _, set} ->
- <<_ObjSz0:32, _T/binary>> = KeysObjs;
- _ -> ok
- end) of
- {'EXIT', _} ->
- bad_object;
- ok ->
- ok
- end.
-
-%% Not inlined
-test3(KeysObjs, C, Ts) ->
- case catch fto_objects(KeysObjs, C, Ts) of
- {'EXIT', _} ->
- bad_object;
- ok ->
- ok
- end.
-
-%% Inlined.
-to_objects(Bin, {binary, _, set}, _Ts) ->
- <<_ObjSz0:32, _T/binary>> = Bin,
- ok;
-to_objects(<<_ObjSz0:32, _T/binary>> ,_, _) ->
- ok;
-to_objects(_Bin, _, _Ts) ->
- ok.
-
-%% Not Inlined.
-fto_objects(Bin, {binary, _, set}, _Ts) ->
- <<_ObjSz0:32, _T/binary>> = Bin,
- ok;
-fto_objects(<<_ObjSz0:32, _T/binary>> ,_,_) ->
- ok;
-fto_objects(_Bin, _, _Ts) ->
- ok.
-
diff --git a/system/doc/efficiency_guide/binaryhandling.xml b/system/doc/efficiency_guide/binaryhandling.xml
index b500329ef9..d92da17390 100644
--- a/system/doc/efficiency_guide/binaryhandling.xml
+++ b/system/doc/efficiency_guide/binaryhandling.xml
@@ -384,8 +384,8 @@ export ERL_COMPILER_OPTIONS=bin_opt_info]]></code>
<p>The warnings look as follows:</p>
<code type="erl"><![CDATA[
-./efficiency_guide.erl:60: Warning: NOT OPTIMIZED: sub binary is used or returned
-./efficiency_guide.erl:62: Warning: OPTIMIZED: creation of sub binary delayed]]></code>
+./efficiency_guide.erl:60: Warning: NOT OPTIMIZED: binary is returned from the function
+./efficiency_guide.erl:62: Warning: OPTIMIZED: match context reused]]></code>
<p>To make it clearer exactly what code the warnings refer to, the
warnings in the following examples are inserted as comments
@@ -393,10 +393,10 @@ export ERL_COMPILER_OPTIONS=bin_opt_info]]></code>
<code type="erl"><![CDATA[
after_zero(<<0,T/binary>>) ->
- %% NOT OPTIMIZED: sub binary is used or returned
+ %% BINARY CREATED: binary is returned from the function
T;
after_zero(<<_,T/binary>>) ->
- %% OPTIMIZED: creation of sub binary delayed
+ %% OPTIMIZED: match context reused
after_zero(T);
after_zero(<<>>) ->
<<>>.]]></code>