Change the calling convention for BIFs

The current calling convention for BIFs makes it necessary to
handle each arity specially, since each argument for the BIF
also becomes an argument for the C function implementing the BIF,
which makes it hard to allow BIFs with any number of arguments.

Change the calling convention for BIFs, so that BIF arguments are
passed in an array to the C function implementing the BIF.

1 files changed, 35 insertions, 72 deletions

diff --git a/erts/emulator/beam/beam_emu.c b/erts/emulator/beam/beam_emu.c
index dd4bf6be07..537a94ce29 100644
--- a/erts/emulator/beam/beam_emu.c
+++ b/erts/emulator/beam/beam_emu.c
@@ -2209,16 +2209,16 @@ void process_main(void)
 
  OpCase(bif1_fbsd):
     {
-	Eterm (*bf)(Process*, Eterm);
-	Eterm arg;
+	Eterm (*bf)(Process*, Eterm*);
+	Eterm tmp_reg[1];
 	Eterm result;
 
-	GetArg1(2, arg);
+	GetArg1(2, tmp_reg[0]);
 	bf = (BifFunction) Arg(1);
 	c_p->fcalls = FCALLS;
 	PROCESS_MAIN_CHK_LOCKS(c_p);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	result = (*bf)(c_p, arg);
+	result = (*bf)(c_p, tmp_reg);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
 	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
 	PROCESS_MAIN_CHK_LOCKS(c_p);
@@ -2237,17 +2237,17 @@ void process_main(void)
 
  OpCase(bif1_body_bsd):
     {
-	Eterm (*bf)(Process*, Eterm);
+	Eterm (*bf)(Process*, Eterm*);
 
-	Eterm arg;
+	Eterm tmp_reg[1];
 	Eterm result;
 
-	GetArg1(1, arg);
+	GetArg1(1, tmp_reg[0]);
 	bf = (BifFunction) Arg(0);
 	c_p->fcalls = FCALLS;
 	PROCESS_MAIN_CHK_LOCKS(c_p);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	result = (*bf)(c_p, arg);
+	result = (*bf)(c_p, tmp_reg);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
 	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
 	PROCESS_MAIN_CHK_LOCKS(c_p);
@@ -2256,7 +2256,7 @@ void process_main(void)
 	if (is_value(result)) {
 	    StoreBifResult(2, result);
 	}
-	reg[0] = arg;
+	reg[0] = tmp_reg[0];
 	SWAPOUT;
 	I = handle_error(c_p, I, reg, bf);
 	goto post_error_handling;
@@ -2380,14 +2380,15 @@ void process_main(void)
   */
  OpCase(i_bif2_fbd):
     {
-	Eterm (*bf)(Process*, Eterm, Eterm);
+	Eterm tmp_reg[2] = {tmp_arg1, tmp_arg2};
+	Eterm (*bf)(Process*, Eterm*);
 	Eterm result;
 
 	bf = (BifFunction) Arg(1);
 	c_p->fcalls = FCALLS;
 	PROCESS_MAIN_CHK_LOCKS(c_p);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	result = (*bf)(c_p, tmp_arg1, tmp_arg2);
+	result = (*bf)(c_p, tmp_reg);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
 	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
 	PROCESS_MAIN_CHK_LOCKS(c_p);
@@ -2405,13 +2406,14 @@ void process_main(void)
   */
  OpCase(i_bif2_body_bd):
     {
-	Eterm (*bf)(Process*, Eterm, Eterm);
+	Eterm tmp_reg[2] = {tmp_arg1, tmp_arg2};
+	Eterm (*bf)(Process*, Eterm*);
 	Eterm result;
 
 	bf = (BifFunction) Arg(0);
 	PROCESS_MAIN_CHK_LOCKS(c_p);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	result = (*bf)(c_p, tmp_arg1, tmp_arg2);
+	result = (*bf)(c_p, tmp_reg);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
 	ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
 	PROCESS_MAIN_CHK_LOCKS(c_p);
@@ -2433,7 +2435,7 @@ void process_main(void)
      */
  OpCase(call_bif0_e):
     {
-	Eterm (*bf)(Process*, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
+	Eterm (*bf)(Process*, Eterm*, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
 
 	PRE_BIF_SWAPOUT(c_p);
 	c_p->fcalls = FCALLS - 1;
@@ -2442,7 +2444,7 @@ void process_main(void)
 	}
 
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	r(0) = (*bf)(c_p, I);
+	r(0) = (*bf)(c_p, reg, I);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(r(0)));
 	ERTS_HOLE_CHECK(c_p);
 	POST_BIF_GC_SWAPIN_0(c_p, r(0));
@@ -2466,7 +2468,7 @@ void process_main(void)
 
  OpCase(call_bif1_e):
     {
-	Eterm (*bf)(Process*, Eterm, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
+	Eterm (*bf)(Process*, Eterm*, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
 	Eterm result;
 	BeamInstr *next;
 
@@ -2477,7 +2479,8 @@ void process_main(void)
 	PreFetch(1, next);
 	PRE_BIF_SWAPOUT(c_p);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	result = (*bf)(c_p, r(0), I);
+	reg[0] = r(0);
+	result = (*bf)(c_p, reg, I);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
 	ERTS_HOLE_CHECK(c_p);
 	POST_BIF_GC_SWAPIN(c_p, result, reg, 1);
@@ -2501,7 +2504,7 @@ void process_main(void)
 
  OpCase(call_bif2_e):
     {
-	Eterm (*bf)(Process*, Eterm, Eterm, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
+	Eterm (*bf)(Process*, Eterm*, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
 	Eterm result;
 	BeamInstr *next;
 
@@ -2514,7 +2517,8 @@ void process_main(void)
 	CHECK_TERM(r(0));
 	CHECK_TERM(x(1));
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	result = (*bf)(c_p, r(0), x(1), I);
+	reg[0] = r(0);
+	result = (*bf)(c_p, reg, I);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
 	ERTS_HOLE_CHECK(c_p);
 	POST_BIF_GC_SWAPIN(c_p, result, reg, 2);
@@ -2538,7 +2542,7 @@ void process_main(void)
 
  OpCase(call_bif3_e):
     {
-	Eterm (*bf)(Process*, Eterm, Eterm, Eterm, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
+	Eterm (*bf)(Process*, Eterm*, BeamInstr*) = GET_BIF_ADDRESS(Arg(0));
 	Eterm result;
 	BeamInstr *next;
 
@@ -2549,7 +2553,8 @@ void process_main(void)
 	}
 	PreFetch(1, next);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-	result = (*bf)(c_p, r(0), x(1), x(2), I);
+	reg[0] = r(0);
+	result = (*bf)(c_p, reg, I);
 	ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(result));
 	ERTS_HOLE_CHECK(c_p);
 	POST_BIF_GC_SWAPIN(c_p, result, reg, 3);
@@ -3326,64 +3331,23 @@ void process_main(void)
 	    ASSERT(bif_nif_arity <= 3);
 	    ERTS_SMP_UNREQ_PROC_MAIN_LOCK(c_p);
 	    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-	    switch (bif_nif_arity) {
-	    case 3:
-		{
-		    Eterm (*bf)(Process*, Eterm, Eterm, Eterm, BeamInstr*) = vbf;
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-		    nif_bif_result = (*bf)(c_p, r(0), x(1), x(2), I);
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p) ||
-			   is_non_value(nif_bif_result));
-		    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-		    PROCESS_MAIN_CHK_LOCKS(c_p);
-		}
-		break;
-	    case 2:
-		{
-		    Eterm (*bf)(Process*, Eterm, Eterm, BeamInstr*) = vbf;
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-		    nif_bif_result = (*bf)(c_p, r(0), x(1), I);
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p) ||
-			   is_non_value(nif_bif_result));
-		    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-		    PROCESS_MAIN_CHK_LOCKS(c_p);
-		}
-		break;
-	    case 1:
-		{
-		    Eterm (*bf)(Process*, Eterm, BeamInstr*) = vbf;
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-		    nif_bif_result = (*bf)(c_p, r(0), I);
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p) ||
-			   is_non_value(nif_bif_result));
-		    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-		    PROCESS_MAIN_CHK_LOCKS(c_p);
-		}
-		break;
-	    case 0:
-		{
-		    Eterm (*bf)(Process*, BeamInstr*) = vbf;
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p));
-		    nif_bif_result = (*bf)(c_p, I);
-		    ASSERT(!ERTS_PROC_IS_EXITING(c_p) ||
-			   is_non_value(nif_bif_result));
-		    ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
-		    PROCESS_MAIN_CHK_LOCKS(c_p);
-		    break;
-		}
-	    default:
-		erl_exit(1, "apply_bif: invalid arity: %u\n",
-			 bif_nif_arity);
+	    reg[0] = r(0);
+	    {
+		Eterm (*bf)(Process*, Eterm*, BeamInstr*) = vbf;
+		ASSERT(!ERTS_PROC_IS_EXITING(c_p));
+		nif_bif_result = (*bf)(c_p, reg, I);
+		ASSERT(!ERTS_PROC_IS_EXITING(c_p) ||
+		       is_non_value(nif_bif_result));
+		ERTS_VERIFY_UNUSED_TEMP_ALLOC(c_p);
+		PROCESS_MAIN_CHK_LOCKS(c_p);
 	    }
 
 	apply_bif_or_nif_epilogue:
 	    ERTS_SMP_REQ_PROC_MAIN_LOCK(c_p);
 	    ERTS_HOLE_CHECK(c_p);
 	    if (c_p->mbuf) {
-		reg[0] = r(0);
 		nif_bif_result = erts_gc_after_bif_call(c_p, nif_bif_result,
 						  reg, bif_nif_arity);
-		r(0) = reg[0];
 	    }
 	    SWAPIN;  /* There might have been a garbage collection. */
 	    FCALLS = c_p->fcalls;
@@ -3404,7 +3368,6 @@ void process_main(void)
 		}
 		Dispatch();
 	    }
-	    reg[0] = r(0);
 	    I = handle_error(c_p, c_p->cp, reg, vbf);
 	    goto post_error_handling;
 	}