http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56547
Oleg Endo <olegendo at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2013-05-16
Component|target |tree-optimization
Ever confirmed|0 |1
--- Comment #1 from Oleg Endo <olegendo at gcc dot gnu.org> ---
This looks like a tree optimization issue.
In tree-ssa-math-ops.c, the function 'convert_mult_to_fma' bails out in the
first for-each at:
if (!is_gimple_assign (use_stmt))
return false;
Apart from that, it still might be a good idea to put the SH fmac combine
patterns back, which I removed when adding support for the FMA patterns.
The following should do.
Index: gcc/config/sh/sh.md
===================================================================
--- gcc/config/sh/sh.md (revision 198802)
+++ gcc/config/sh/sh.md (working copy)
@@ -12285,6 +12285,29 @@
"fmac.s %1, %2, %0"
[(set_attr "type" "fparith_media")])
+;; For some cases such as 'a * b + a' the FMA pattern is not generated by
+;; previous transformations. If FMA is generally allowed, let the combine
+;; pass utilize it.
+(define_insn "*fmasf4"
+ [(set (match_operand:SF 0 "fp_arith_reg_operand" "=f")
+ (plus:SF (mult:SF (match_operand:SF 1 "fp_arith_reg_operand" "%w")
+ (match_operand:SF 2 "fp_arith_reg_operand" "f"))
+ (match_operand:SF 3 "arith_reg_operand" "0")))
+ (use (match_operand:PSI 4 "fpscr_operand" "c"))]
+ "TARGET_SH2E && flag_fp_contract_mode != FP_CONTRACT_OFF"
+ "fmac %1,%2,%0"
+ [(set_attr "type" "fp")
+ (set_attr "fp_mode" "single")])
+
+(define_insn "*fmasf4_media"
+ [(set (match_operand:SF 0 "fp_arith_reg_operand" "=f")
+ (plus:SF (mult:SF (match_operand:SF 1 "fp_arith_reg_operand" "%f")
+ (match_operand:SF 2 "fp_arith_reg_operand" "f"))
+ (match_operand:SF 3 "fp_arith_reg_operand" "0")))]
+ "TARGET_SHMEDIA_FPU && flag_fp_contract_mode != FP_CONTRACT_OFF"
+ "fmac.s %1, %2, %0"
+ [(set_attr "type" "fparith_media")])
+
(define_expand "divsf3"
[(set (match_operand:SF 0 "arith_reg_operand" "")
(div:SF (match_operand:SF 1 "arith_reg_operand" "")
