From: Andi Kleen <a...@linux.intel.com>
The peephole that removes the code to compute a tristate for cmpstrnsi
when only a boolean jump is needed never triggers in my tests. Just
remove it.
gcc/:
2014-09-27 Andi Kleen <a...@linux.intel.com>
* config/i386/i386.md: Remove peepholes for cmpstrn*.
---
gcc/config/i386/i386.md | 77 -------------------------------------------------
1 file changed, 77 deletions(-)
diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
index 004302d..98df8e1 100644
--- a/gcc/config/i386/i386.md
+++ b/gcc/config/i386/i386.md
@@ -16297,83 +16297,6 @@
(const_string "0")
(const_string "*")))
(set_attr "prefix_rep" "1")])
-
-;; Peephole optimizations to clean up after cmpstrn*. This should be
-;; handled in combine, but it is not currently up to the task.
-;; When used for their truth value, the cmpstrn* expanders generate
-;; code like this:
-;;
-;; repz cmpsb
-;; seta %al
-;; setb %dl
-;; cmpb %al, %dl
-;; jcc label
-;;
-;; The intermediate three instructions are unnecessary.
-
-;; This one handles cmpstrn*_nz_1...
-(define_peephole2
- [(parallel[
- (set (reg:CC FLAGS_REG)
- (compare:CC (mem:BLK (match_operand 4 "register_operand"))
- (mem:BLK (match_operand 5 "register_operand"))))
- (use (match_operand 6 "register_operand"))
- (use (match_operand:SI 3 "immediate_operand"))
- (clobber (match_operand 0 "register_operand"))
- (clobber (match_operand 1 "register_operand"))
- (clobber (match_operand 2 "register_operand"))])
- (set (match_operand:QI 7 "register_operand")
- (gtu:QI (reg:CC FLAGS_REG) (const_int 0)))
- (set (match_operand:QI 8 "register_operand")
- (ltu:QI (reg:CC FLAGS_REG) (const_int 0)))
- (set (reg FLAGS_REG)
- (compare (match_dup 7) (match_dup 8)))
- ]
- "peep2_reg_dead_p (4, operands[7]) && peep2_reg_dead_p (4, operands[8])"
- [(parallel[
- (set (reg:CC FLAGS_REG)
- (compare:CC (mem:BLK (match_dup 4))
- (mem:BLK (match_dup 5))))
- (use (match_dup 6))
- (use (match_dup 3))
- (clobber (match_dup 0))
- (clobber (match_dup 1))
- (clobber (match_dup 2))])])
-
-;; ...and this one handles cmpstrn*_1.
-(define_peephole2
- [(parallel[
- (set (reg:CC FLAGS_REG)
- (if_then_else:CC (ne (match_operand 6 "register_operand")
- (const_int 0))
- (compare:CC (mem:BLK (match_operand 4 "register_operand"))
- (mem:BLK (match_operand 5 "register_operand")))
- (const_int 0)))
- (use (match_operand:SI 3 "immediate_operand"))
- (use (reg:CC FLAGS_REG))
- (clobber (match_operand 0 "register_operand"))
- (clobber (match_operand 1 "register_operand"))
- (clobber (match_operand 2 "register_operand"))])
- (set (match_operand:QI 7 "register_operand")
- (gtu:QI (reg:CC FLAGS_REG) (const_int 0)))
- (set (match_operand:QI 8 "register_operand")
- (ltu:QI (reg:CC FLAGS_REG) (const_int 0)))
- (set (reg FLAGS_REG)
- (compare (match_dup 7) (match_dup 8)))
- ]
- "peep2_reg_dead_p (4, operands[7]) && peep2_reg_dead_p (4, operands[8])"
- [(parallel[
- (set (reg:CC FLAGS_REG)
- (if_then_else:CC (ne (match_dup 6)
- (const_int 0))
- (compare:CC (mem:BLK (match_dup 4))
- (mem:BLK (match_dup 5)))
- (const_int 0)))
- (use (match_dup 3))
- (use (reg:CC FLAGS_REG))
- (clobber (match_dup 0))
- (clobber (match_dup 1))
- (clobber (match_dup 2))])])
;; Conditional move instructions.
--
2.1.1
