Commit 2219f0c2 by Oleg Endo

re PR target/51244 ([SH] Inefficient conditional branch and code around T bit)

gcc/
	PR target/51244
	* config/sh/sh.md (*mov_t_msb_neg): Convert split into insn_and_split.

From-SVN: r219062
parent 28547098
2014-12-24 Oleg Endo <olegendo@gcc.gnu.org>
PR target/51244
* config/sh/sh.md (*mov_t_msb_neg): Convert split into insn_and_split.
2014-12-24 Uros Bizjak <ubizjak@gmail.com>
* gengtype.h (xasprintf): Remove declaration.
......@@ -11601,8 +11601,8 @@ label:
(set (match_dup 0) (xor:SI (match_dup 0) (const_int 1)))])
;; Use negc to store the T bit in a MSB of a reg in the following way:
;; T = 1: 0x80000000 -> reg
;; T = 0: 0x7FFFFFFF -> reg
;; T = 0: 0x80000000 -> reg
;; T = 1: 0x7FFFFFFF -> reg
;; This works because 0 - 0x80000000 = 0x80000000.
;;
;; This insn must not match again after it has been split into the constant
......@@ -11635,27 +11635,27 @@ label:
"negc %1,%0"
[(set_attr "type" "arith")])
;; These are essentially the same as above, but with the inverted T bit.
;; Combine recognizes the split patterns, but does not take them sometimes
;; if the T_REG clobber is specified. Instead it tries to split out the
;; T bit negation. Since these splits are supposed to be taken only by
;; combine, it will see the T_REG clobber of the *mov_t_msb_neg insn, so this
;; should be fine.
(define_split
(define_insn_and_split "*mov_t_msb_neg"
[(set (match_operand:SI 0 "arith_reg_dest")
(plus:SI (match_operand 1 "negt_reg_operand")
(const_int 2147483647)))] ;; 0x7fffffff
"TARGET_SH1 && can_create_pseudo_p ()"
(const_int 2147483647))) ;; 0x7fffffff
(clobber (reg:SI T_REG))]
"TARGET_SH1"
"#"
"&& can_create_pseudo_p ()"
[(parallel [(set (match_dup 0)
(minus:SI (const_int -2147483648) (reg:SI T_REG)))
(clobber (reg:SI T_REG))])])
(define_split
(define_insn_and_split "*mov_t_msb_neg"
[(set (match_operand:SI 0 "arith_reg_dest")
(if_then_else:SI (match_operand 1 "t_reg_operand")
(const_int 2147483647) ;; 0x7fffffff
(const_int -2147483648)))] ;; 0x80000000
"TARGET_SH1 && can_create_pseudo_p ()"
(const_int -2147483648))) ;; 0x80000000
(clobber (reg:SI T_REG))]
"TARGET_SH1"
"#"
"&& can_create_pseudo_p ()"
[(parallel [(set (match_dup 0)
(minus:SI (const_int -2147483648) (reg:SI T_REG)))
(clobber (reg:SI T_REG))])])
......
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