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(sne): Modified to use negc instead of xor.

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(sne+1): New define_split for new sne pattern.

From-SVN: r13848
This commit is contained in:
Jim Wilson 1997-04-10 15:39:01 -07:00
parent f3cd53755b
commit 8bca10f462
1 changed files with 33 additions and 4 deletions
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37
gcc/config/sh/sh.md
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@ -2287,12 +2287,41 @@
""
"operands[1] = prepare_scc_operands (GEU);")
;; sne moves the complement of the T reg to DEST like this:
;; cmp/eq ...
;; mov #-1,temp
;; negc temp,dest
;; This is better than xoring compare result with 1 because it does
;; not require r0 and further, the -1 may be CSE-ed or lifted out of a
;; loop.
(define_expand "sne"
[(set (match_operand:SI 0 "arith_reg_operand" "")
(match_dup 1))
(set (match_dup 0) (xor:SI (match_dup 0) (const_int 1)))]
[(set (match_dup 2) (const_int -1))
(parallel [(set (match_operand:SI 0 "arith_reg_operand" "")
(neg:SI (plus:SI (match_dup 1)
(match_dup 2))))
(set (reg:SI 18)
(ne:SI (ior:SI (match_dup 1) (match_dup 2))
(const_int 0)))])]
""
"operands[1] = prepare_scc_operands (EQ);")
"
{
operands[1] = prepare_scc_operands (EQ);
operands[2] = gen_reg_rtx (SImode);
}")
;; Recognize mov #-1/negc/neg sequence, and change it to movt/add #-1.
;; This prevents a regression that occured when we switched from xor to
;; mov/neg for sne.
(define_split
[(set (match_operand:SI 0 "arith_reg_operand" "")
(plus:SI (reg:SI 18)
(const_int -1)))]
""
[(set (match_dup 0) (eq:SI (reg:SI 18) (const_int 1)))
(set (match_dup 0) (plus:SI (match_dup 0) (const_int -1)))]
"")
;; -------------------------------------------------------------------------
;; Instructions to cope with inline literal tables