Store pointers to heap data in 32-bit words

Store Erlang terms in 32-bit entities on the heap, expanding the
pointers to 64-bit when needed. This works because all terms are stored
on addresses in the 32-bit address range (the 32 most significant bits
of pointers to term data are always 0).

Introduce a new datatype called UWord (along with its companion SWord),
which is an integer having the exact same size as the machine word
(a void *), but might be larger than Eterm/Uint.

Store code as machine words, as the instructions are pointers to
executable code which might reside outside the 32-bit address range.

Continuation pointers are stored on the 32-bit stack and hence must
point to addresses in the low range, which means that loaded beam code
much be placed in the low 32-bit address range (but, as said earlier,
the instructions themselves are full words).

No Erlang term data can be stored on C stacks (enforced by an
earlier commit).

This version gives a prompt, but test cases still fail (and dump core).

The loader (and emulator loop) has instruction packing disabled.

The main issues has been in rewriting loader and actual virtual
machine. Subsystems (like distribution) does not work yet.

1 files changed, 55 insertions, 17 deletions

diff --git a/erts/emulator/beam/erl_alloc.c b/erts/emulator/beam/erl_alloc.c
index 4403a19f4a..9c5210fed6 100644
--- a/erts/emulator/beam/erl_alloc.c
+++ b/erts/emulator/beam/erl_alloc.c
@@ -220,7 +220,7 @@ set_default_ll_alloc_opts(struct au_init *ip)
     ip->init.util.ramv		= 0;
     ip->init.util.mmsbc		= 0;
     ip->init.util.mmmbc		= 0;
-    ip->init.util.sbct		= ~((Uint) 0);
+    ip->init.util.sbct		= ~((UWord) 0);
     ip->init.util.name_prefix	= "ll_";
     ip->init.util.alloc_no	= ERTS_ALC_A_LONG_LIVED;
 #ifndef SMALL_MEMORY
@@ -394,7 +394,7 @@ static void init_thr_ix(int static_ixs);
 void
 erts_alloc_init(int *argc, char **argv, ErtsAllocInitOpts *eaiop)
 {
-    Uint extra_block_size = 0;
+    UWord extra_block_size = 0;
     int i;
     erts_alc_hndl_args_init_t init = {
 	0,
@@ -542,7 +542,6 @@ erts_alloc_init(int *argc, char **argv, ErtsAllocInitOpts *eaiop)
 
     sys_alloc_opt(SYS_ALLOC_OPT_TRIM_THRESHOLD, init.trim_threshold);
     sys_alloc_opt(SYS_ALLOC_OPT_TOP_PAD, init.top_pad);
-
     if (erts_allctrs_info[ERTS_FIX_CORE_ALLOCATOR].enabled)
 	erts_fix_core_allocator_ix = ERTS_FIX_CORE_ALLOCATOR;
     else
@@ -719,8 +718,8 @@ start_au_allocator(ErtsAlcType_t alctr_n,
 		     init->init.util.name_prefix);
 	tspec->allctr = (Allctr_t **) states;
 	states = ((char *) states) + sizeof(Allctr_t *) * (tspec->size + 1);
-	states = ((((Uint) states) & ERTS_CACHE_LINE_MASK)
-		  ? (void *) ((((Uint) states) & ~ERTS_CACHE_LINE_MASK)
+	states = ((((UWord) states) & ERTS_CACHE_LINE_MASK)
+		  ? (void *) ((((UWord) states) & ~ERTS_CACHE_LINE_MASK)
 			      + ERTS_CACHE_LINE_SIZE)
 		  : (void *) states);
 	tspec->allctr[0] = init->thr_spec > 0 ? (Allctr_t *) state : (Allctr_t *) NULL;
@@ -2948,9 +2947,9 @@ unsigned long erts_alc_test(unsigned long op,
 #endif
 
 
-#define FENCE_SZ		(3*sizeof(Uint))
+#define FENCE_SZ		(3*sizeof(UWord))
 
-#ifdef ARCH_64
+#if defined(ARCH_64)
 #define FENCE_PATTERN 0xABCDEF97ABCDEF97
 #else
 #define FENCE_PATTERN 0xABCDEF97
@@ -2960,7 +2959,7 @@ unsigned long erts_alc_test(unsigned long op,
 #define TYPE_PATTERN_SHIFT 16
 
 #define FIXED_FENCE_PATTERN_MASK \
-  (~((Uint) (TYPE_PATTERN_MASK << TYPE_PATTERN_SHIFT)))
+  (~((UWord) (TYPE_PATTERN_MASK << TYPE_PATTERN_SHIFT)))
 #define FIXED_FENCE_PATTERN \
   (FENCE_PATTERN & FIXED_FENCE_PATTERN_MASK)
 
@@ -2971,21 +2970,60 @@ unsigned long erts_alc_test(unsigned long op,
   (((P) >> TYPE_PATTERN_SHIFT) & TYPE_PATTERN_MASK)
 
 
+#ifdef  ERTS_ALLOC_UTIL_HARD_DEBUG
+static void *check_memory_fence(void *ptr, Uint *size, ErtsAlcType_t n, int func);
+
+void check_allocated_block( Uint type, void *blk)
+{
+    Uint dummy;
+    check_memory_fence(blk, &dummy, ERTS_ALC_T2N(type), ERTS_ALC_O_FREE);
+}
+
+void check_allocators(void)
+{
+    int i;
+    if (!erts_initialized)
+	return;
+    for (i = ERTS_ALC_A_MIN; i <= ERTS_ALC_A_MAX; ++i) {
+	if (erts_allctrs_info[i].alloc_util) {
+	    ErtsAllocatorFunctions_t *real_af = (ErtsAllocatorFunctions_t *) erts_allctrs[i].extra;
+	    Allctr_t *allctr = real_af->extra;
+	    Carrier_t *ct;
+#ifdef USE_THREADS
+	if (allctr->thread_safe)
+	    erts_mtx_lock(&allctr->mutex);
+#endif
+
+	    if (allctr->check_mbc) {
+		for (ct = allctr->mbc_list.first; ct; ct = ct->next) {
+		    fprintf(stderr,"Checking allocator %d\r\n",i);
+		    allctr->check_mbc(allctr,ct);
+		}
+	    }
+#ifdef USE_THREADS
+	if (allctr->thread_safe)
+	    erts_mtx_unlock(&allctr->mutex);
+#endif
+	}
+    }
+}
+#endif
+
 static void *
 set_memory_fence(void *ptr, Uint sz, ErtsAlcType_t n)
 {
-    Uint *ui_ptr;
-    Uint pattern;
+    UWord *ui_ptr;
+    UWord pattern;
 
     if (!ptr)
 	return NULL;
 
-    ui_ptr = (Uint *) ptr;
+    ui_ptr = (UWord *) ptr;
     pattern = MK_PATTERN(n);
     
     *(ui_ptr++) = sz;
     *(ui_ptr++) = pattern;
-    memcpy((void *) (((char *) ui_ptr)+sz), (void *) &pattern, sizeof(Uint));
+    memcpy((void *) (((char *) ui_ptr)+sz), (void *) &pattern, sizeof(UWord));
 
     return (void *) ui_ptr;
 }
@@ -2995,14 +3033,14 @@ check_memory_fence(void *ptr, Uint *size, ErtsAlcType_t n, int func)
 {
     Uint sz;
     Uint found_type;
-    Uint pre_pattern;
-    Uint post_pattern;
-    Uint *ui_ptr;
+    UWord pre_pattern;
+    UWord post_pattern;
+    UWord *ui_ptr;
 
     if (!ptr)
 	return NULL;
 
-    ui_ptr = (Uint *) ptr;
+    ui_ptr = (UWord *) ptr;
     pre_pattern = *(--ui_ptr);
     *size = sz = *(--ui_ptr);
 
@@ -3015,7 +3053,7 @@ check_memory_fence(void *ptr, Uint *size, ErtsAlcType_t n, int func)
 		     (unsigned long) ptr);
     }
 
-    memcpy((void *) &post_pattern, (void *) (((char *)ptr)+sz), sizeof(Uint));
+    memcpy((void *) &post_pattern, (void *) (((char *)ptr)+sz), sizeof(UWord));
 
     if (post_pattern != MK_PATTERN(n)
 	|| pre_pattern != post_pattern) {