Merge lp:~uweigand/gcc-linaro/lp-685352 into lp:gcc-linaro/4.5

[Ulrich Weigand]

Fix LP #685352 by backporting mainline fix for PR rtl-optimization/47299.

=== modified file 'ChangeLog.linaro'
--- ChangeLog.linaro	2011-01-13 18:18:11 +0000
+++ ChangeLog.linaro	2011-01-18 19:24:33 +0000
@@ -1,3 +1,23 @@
[phone]  Ulrich Weigand  <[e-mail]>
+
+	LP: #685352
+	Backport from mainline:
+
+	2011-01-18  Jakub Jelinek  <[e-mail]>
+
+	gcc/
+	PR rtl-optimization/47299
+	* expr.c (expand_expr_real_2) <case WIDEN_MULT_EXPR>: Don't use
+	subtarget.  Use normal multiplication if both operands are
+	constants.
+	* expmed.c (expand_widening_mult): Don't try to optimize constant
+	multiplication if op0 has VOIDmode.  Convert op1 constant to mode
+	before using it.
+
+	gcc/testsuite/
+	PR rtl-optimization/47299
+	* gcc.c-torture/execute/pr47299.c: New test.
+
 2011-01-13  Andrew Stubbs  <[e-mail]>
 
 	gcc/

=== modified file 'gcc/expmed.c'
--- gcc/expmed.c	2010-11-04 12:43:52 +0000
+++ gcc/expmed.c	2011-01-18 19:24:33 +0000
@@ -3355,12 +3355,17 @@
 		      int unsignedp, optab this_optab)
 {
   bool speed = optimize_insn_for_speed_p ();
+  rtx cop1;
 
   if (CONST_INT_P (op1)
-      && (INTVAL (op1) >= 0
+      && GET_MODE (op0) != VOIDmode
+      && (cop1 = convert_modes (mode, GET_MODE (op0), op1,
+				this_optab == umul_widen_optab))
+      && CONST_INT_P (cop1)
+      && (INTVAL (cop1) >= 0
 	  || GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT))
     {
-      HOST_WIDE_INT coeff = INTVAL (op1);
+      HOST_WIDE_INT coeff = INTVAL (cop1);
       int max_cost;
       enum mult_variant variant;
       struct algorithm algorithm;

=== modified file 'gcc/expr.c'
--- gcc/expr.c	2010-12-10 15:34:19 +0000
+++ gcc/expr.c	2011-01-18 19:24:33 +0000
@@ -7621,10 +7621,10 @@
 	      if (optab_handler (this_optab, mode)->insn_code != CODE_FOR_nothing)
 		{
 		  if (TYPE_UNSIGNED (TREE_TYPE (treeop0)))
-		    expand_operands (treeop0, treeop1, subtarget, &op0, &op1,
+		    expand_operands (treeop0, treeop1, NULL_RTX, &op0, &op1,
 				     EXPAND_NORMAL);
 		  else
-		    expand_operands (treeop0, treeop1, subtarget, &op1, &op0,
+		    expand_operands (treeop0, treeop1, NULL_RTX, &op1, &op0,
 				     EXPAND_NORMAL);
 		  goto binop3;
 		}
@@ -7642,7 +7642,8 @@
 	  optab other_optab = zextend_p ? smul_widen_optab : umul_widen_optab;
 	  this_optab = zextend_p ? umul_widen_optab : smul_widen_optab;
 
-	  if (mode == GET_MODE_2XWIDER_MODE (innermode))
+	  if (mode == GET_MODE_2XWIDER_MODE (innermode)
+	      && TREE_CODE (treeop0) != INTEGER_CST)
 	    {
 	      if (optab_handler (this_optab, mode)->insn_code != CODE_FOR_nothing)
 		{

=== added file 'gcc/testsuite/gcc.c-torture/execute/pr47299.c'
--- gcc/testsuite/gcc.c-torture/execute/pr47299.c	1970-01-01 00:00:00 +0000
+++ gcc/testsuite/gcc.c-torture/execute/pr47299.c	2011-01-18 19:24:33 +0000
@@ -0,0 +1,17 @@
+/* PR rtl-optimization/47299 */
+
+extern void abort (void);
+
+__attribute__ ((noinline, noclone)) unsigned short
+foo (unsigned char x)
+{
+  return x * 255;
+}
+
+int
+main ()
+{
+  if (foo (0x40) != 0x3fc0)
+    abort ();
+  return 0;
+}