From: Aleksey Demakov <ademakov@gmail.com>
Date: Fri, 18 Aug 2006 18:14:27 +0000 (+0000)
Subject: fix a problem with the clobber flag being ignored
X-Git-Tag: before.move.to.git~213
X-Git-Url: https://git.unchartedbackwaters.co.uk/w/?a=commitdiff_plain;h=02b95ffc5eb96b220d5b45633116b9e9eb5f6ffb;p=francis%2Flibjit.git

fix a problem with the clobber flag being ignored
---

diff --git a/ChangeLog b/ChangeLog
index ccee029..d12e494 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2006-08-19  Aleksey Demakov  <ademakov@gmail.com>
+
+	* jit/jit-reg-alloc.c (set_regdesc_flags): fix a problem with the
+	clobber	flag being ignored. The problem was introduced by the patch
+	from 2006-06-17.
+
 2006-08-15  Thomas Cort  <linuxgeek@gmail.com>
 	* jit/jit-rules-alpha.c jit/jit-rules-alpha.h jit/jit-rules-alpha.ins
 	Add a TODO() macro to print unimplemented warnings. Fix some 
diff --git a/jit/jit-reg-alloc.c b/jit/jit-reg-alloc.c
index d14ead4..8ea4219 100644
--- a/jit/jit-reg-alloc.c
+++ b/jit/jit-reg-alloc.c
@@ -2165,8 +2165,8 @@ static int
 set_regdesc_flags(jit_gencode_t gen, _jit_regs_t *regs, int index)
 {
   	_jit_regdesc_t *desc;
-	int reg, other_reg;
-	int clobber, stack_start;
+	int reg, other_reg, stack_start;
+	int clobber, clobber_input;
 
 #ifdef JIT_REG_DEBUG
 	printf("set_regdesc_flags(index = %d)\n", index);
@@ -2199,6 +2199,18 @@ set_regdesc_flags(jit_gencode_t gen, _jit_regs_t *regs, int index)
 
 	/* See if the value clobbers the register it is assigned to. */
 	clobber = clobbers_register(gen, regs, index, desc->reg, desc->other_reg);
+	if(jit_reg_is_used(regs->clobber, desc->reg))
+	{
+		clobber_input = 1;
+	}
+	else if(desc->other_reg >= 0 && jit_reg_is_used(regs->clobber, desc->other_reg))
+	{
+		clobber_input = 1;
+	}
+	else
+	{
+		clobber_input = (clobber & CLOBBER_INPUT_VALUE) != 0;
+	}
 	if((clobber & CLOBBER_REG) != 0)
 	{
 		jit_reg_set_used(regs->clobber, desc->reg);
@@ -2235,7 +2247,7 @@ set_regdesc_flags(jit_gencode_t gen, _jit_regs_t *regs, int index)
 				{
 					if(desc->value != regs->descs[0].value)
 					{
-	   					clobber |= CLOBBER_INPUT_VALUE;
+	   					clobber_input = 1;
 					}
 				}
 			}
@@ -2305,7 +2317,7 @@ set_regdesc_flags(jit_gencode_t gen, _jit_regs_t *regs, int index)
 		{
 			if(desc->used)
 			{
-				if(!desc->copy && (clobber & CLOBBER_INPUT_VALUE) != 0)
+				if(!desc->copy && clobber_input)
 				{
 					desc->save = 1;
 					desc->kill = 1;
@@ -2324,7 +2336,7 @@ set_regdesc_flags(jit_gencode_t gen, _jit_regs_t *regs, int index)
 		{
 			if(desc->used)
 			{
-				if((clobber & CLOBBER_INPUT_VALUE) != 0)
+				if(clobber_input)
 				{
 					desc->kill = 1;
 				}