This patch improves address combine for x32 by forcing the memory memory
operand of PLUS operation into register. Tested on Linux/x86-64 with
-mx32. OK for trunk?
Thanks.
H.J.
---
2011-10-03 H.J. Lu <hongjiu...@intel.com>
PR target/50603
* config/i386/i386.c (ix86_fixup_binary_operands): Force the
memory operand of PLUS operation into register for x32.
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 9b079af..922f691 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -15713,6 +15713,16 @@ ix86_fixup_binary_operands (enum rtx_code code, enum
machine_mode mode,
else
src2 = force_reg (mode, src2);
}
+ else
+ {
+ /* Improve address combine in x32 mode. */
+ if (TARGET_X32
+ && code == PLUS
+ && !MEM_P (dst)
+ && !MEM_P (src1)
+ && MEM_P (src2) )
+ src2 = force_reg (mode, src2);
+ }
/* If the destination is memory, and we do not have matching source
operands, do things in registers. */
