From: epetrich <epetrich@4a8a32a2-be11-0410-ad9d-d568d2c75423>
Date: Thu, 30 Oct 2003 05:42:53 +0000 (+0000)
Subject: Fixed a number of problems revealed by bug #827883.
X-Git-Url: https://git.gag.com/?a=commitdiff_plain;h=30244100339d65c90eb0f45a7c3be6fbc9805f30;p=fw%2Fsdcc

Fixed a number of problems revealed by bug #827883.
* src/SDCCloop.c (loopInvariants): Spill location of the
result operand should be recomputed if extracted from
a loop. Also, don't extract assignments of an iTemp
from a literal.
* src/SDCCast.c (isConformingBody): loop reversal should
not occur if the control variable is involved with a
relational operator.


git-svn-id: https://sdcc.svn.sourceforge.net/svnroot/sdcc/trunk/sdcc@2967 4a8a32a2-be11-0410-ad9d-d568d2c75423
---

diff --git a/ChangeLog b/ChangeLog
index df792fe5..7ebc3ad7 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2003-10-30 Erik Petrich <epetrich@ivorytower.norman.ok.us>
+
+	Fixed a number of problems revealed by bug #827883.
+	* src/SDCCloop.c (loopInvariants): Spill location of the
+	result operand should be recomputed if extracted from
+	a loop. Also, don't extract assignments of an iTemp
+	from a literal.
+	* src/SDCCast.c (isConformingBody): loop reversal should
+	not occur if the control variable is involved with a
+	relational operator.
+
 2003-10-28 Bernhard Held <bernhard@bernhardheld.de>
 
 	* .version: bumped to 2.3.6 to reflect the big improvements
diff --git a/src/SDCCast.c b/src/SDCCast.c
index 7db25f4f..c0d2787a 100644
--- a/src/SDCCast.c
+++ b/src/SDCCast.c
@@ -1682,6 +1682,14 @@ isConformingBody (ast * pbody, symbol * sym, ast * body)
     case '?':
     case ':':
     case SIZEOF:		/* evaluate wihout code generation */
+      
+      if (IS_AST_SYM_VALUE (pbody->left) &&
+	  isSymbolEqual (AST_SYMBOL (pbody->left), sym))
+	return FALSE;
+
+      if (IS_AST_SYM_VALUE (pbody->right) &&
+	  isSymbolEqual (AST_SYMBOL (pbody->right), sym))
+	return FALSE;
 
       return isConformingBody (pbody->left, sym, body) &&
 	isConformingBody (pbody->right, sym, body);
diff --git a/src/SDCCloop.c b/src/SDCCloop.c
index 783fd3d9..1ff5e2cd 100644
--- a/src/SDCCloop.c
+++ b/src/SDCCloop.c
@@ -464,6 +464,13 @@ loopInvariants (region * theLoop, eBBlock ** ebbs, int count)
 
 	  if (SKIP_IC (ic) || POINTER_SET (ic) || ic->op == IFX)
 	    continue;
+	  
+	  /* iTemp assignment from a literal may be invariant, but it
+	     will needlessly increase register pressure if the
+	     iCode(s) that use this iTemp are not also invariant */
+	  if (ic->op=='=' && IS_ITEMP (IC_RESULT (ic))
+	      && IS_OP_LITERAL (IC_RIGHT (ic)))
+	    continue;
 
 	  /* if result is volatile then skip */
 	  if (IC_RESULT (ic) &&
@@ -507,7 +514,8 @@ loopInvariants (region * theLoop, eBBlock ** ebbs, int count)
 	      applyToSet (theLoop->regBlocks, hasNonPtrUse, IC_LEFT (ic)))
 	    continue;
 
-	  /* if both the left & right are invariants : then check that */
+
+          /* if both the left & right are invariants : then check that */
 	  /* this definition exists in the out definition of all the  */
 	  /* blocks, this will ensure that this is not assigned any   */
 	  /* other value in the loop , and not used in this block     */
@@ -518,7 +526,7 @@ loopInvariants (region * theLoop, eBBlock ** ebbs, int count)
 	      eBBlock *sBlock;
 	      set *lSet = setFromSet (theLoop->regBlocks);
 
-	      /* if this block does not dominate all exists */
+	      /* if this block does not dominate all exits */
 	      /* make sure this defintion is not used anywhere else */
 	      if (!domsAllExits)
 		{
@@ -567,7 +575,9 @@ loopInvariants (region * theLoop, eBBlock ** ebbs, int count)
 	      /* now we know it is a true invariant */
 	      /* remove it from the insts chain & put */
 	      /* in the invariant set                */
-	      OP_SYMBOL (IC_RESULT (ic))->isinvariant = 1;
+	      
+              OP_SYMBOL (IC_RESULT (ic))->isinvariant = 1;
+              SPIL_LOC (IC_RESULT (ic)) = NULL;
 	      remiCodeFromeBBlock (lBlock, ic);
 
 	      /* maintain the data flow */