optabs.c (expand_binop): Attempt to reuse pseudos for duplicate non-volatile…

optabs.c (expand_binop): Attempt to reuse pseudos for duplicate non-volatile operands of binary operations.


	* optabs.c (expand_binop): Attempt to reuse pseudos for duplicate
	non-volatile operands of binary operations.
	(prepare_cmp_insn): Likewise.

From-SVN: r67417

gcc/ChangeLog

 2003-06-03  Roger Sayle  <roger@eyesopen.com>
 
+	* optabs.c (expand_binop): Attempt to reuse pseudos for duplicate
+	non-volatile operands of binary operations.
+	(prepare_cmp_insn): Likewise.
+
+2003-06-03  Roger Sayle  <roger@eyesopen.com>
+
 	* varasm.c (force_const_mem): Handle alignment of constants not
 	representable as a type in the front-end language.
 

gcc/optabs.c

@@ -700,8 +700,17 @@ expand_binop (mode, binoptab, op0, op1, target, unsignedp, methods)
 
   if (flag_force_mem)
     {
-      op0 = force_not_mem (op0);
-      op1 = force_not_mem (op1);
+      /* Load duplicate non-volatile operands once.  */
+      if (rtx_equal_p (op0, op1) && ! volatile_refs_p (op0))
+	{
+	  op0 = force_not_mem (op0);
+	  op1 = op0;
+	}
+      else
+	{
+	  op0 = force_not_mem (op0);
+	  op1 = force_not_mem (op1);
+	}
     }
 
   /* If subtracting an integer constant, convert this into an addition of
@@ -3587,8 +3596,17 @@ prepare_cmp_insn (px, py, pcomparison, size, pmode, punsignedp, purpose)
 
   if (mode != BLKmode && flag_force_mem)
     {
-      x = force_not_mem (x);
-      y = force_not_mem (y);
+      /* Load duplicate non-volatile operands once.  */
+      if (rtx_equal_p (x, y) && ! volatile_refs_p (x))
+	{
+	  x = force_not_mem (x);
+	  y = x;
+	}
+      else
+	{
+	  x = force_not_mem (x);
+	  y = force_not_mem (y);
+	}
     }
 
   /* If we are inside an appropriately-short loop and one operand is an