Is it ok to commit backported patch from trunk below to gcc 4.6 as long as
bootstrap and tests pass (ongoing)? This is one of the patches that is
significant enough a bug for recent AMD and Intel hardware.
2011-06-29 Harsha Jagasia <harsha.jaga...@amd.com>
Backport from mainline
2011-05-31 Alexandre Oliva <aol...@redhat.com>
* config/i386/i386.c (ix86_rtx_costs): Drop NEG from sub for FMA.
* config/i386/sse.md: Add n to negated FMA pattern names.
Index: config/i386/sse.md
===================================================================
--- config/i386/sse.md (revision 175646)
+++ config/i386/sse.md (working copy)
@@ -2130,7 +2130,7 @@ (define_insn "*fma_fmsub_<mode>"
[(set_attr "type" "ssemuladd")
(set_attr "mode" "<MODE>")])
-(define_insn "*fma_fmadd_<mode>"
+(define_insn "*fma_fnmadd_<mode>"
[(set (match_operand:FMAMODE 0 "register_operand" "=x,x,x")
(fma:FMAMODE
(neg:FMAMODE
@@ -2145,7 +2145,7 @@ (define_insn "*fma_fmadd_<mode>"
[(set_attr "type" "ssemuladd")
(set_attr "mode" "<MODE>")])
-(define_insn "*fma_fmsub_<mode>"
+(define_insn "*fma_fnmsub_<mode>"
[(set (match_operand:FMAMODE 0 "register_operand" "=x,x,x")
(fma:FMAMODE
(neg:FMAMODE
Index: config/i386/i386.c
===================================================================
--- config/i386/i386.c (revision 175646)
+++ config/i386/i386.c (working copy)
@@ -29081,12 +29081,12 @@ ix86_rtx_costs (rtx x, int code, int out
/* Negate in op0 or op2 is free: FMS, FNMA, FNMS. */
sub = XEXP (x, 0);
if (GET_CODE (sub) == NEG)
- sub = XEXP (x, 0);
+ sub = XEXP (sub, 0);
*total += rtx_cost (sub, FMA, speed);
sub = XEXP (x, 2);
if (GET_CODE (sub) == NEG)
- sub = XEXP (x, 0);
+ sub = XEXP (sub, 0);
*total += rtx_cost (sub, FMA, speed);
return true;
}
