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[PATCH 3/6] rs6000: Don't use zero_extract in the bswap:HI splitter
- From: Segher Boessenkool <segher at kernel dot crashing dot org>
- To: gcc-patches at gcc dot gnu dot org
- Cc: dje dot gcc at gmail dot com, Segher Boessenkool <segher at kernel dot crashing dot org>
- Date: Sun, 10 May 2015 09:13:52 -0700
- Subject: [PATCH 3/6] rs6000: Don't use zero_extract in the bswap:HI splitter
- Authentication-results: sourceware.org; auth=none
- References: <cover dot 1431268134 dot git dot segher at kernel dot crashing dot org>
- References: <cover dot 1431268134 dot git dot segher at kernel dot crashing dot org>
The next patch removes the zero_extract insn this splits to. Write
it as (and (lshiftrt ... instead.
Okay for trunk?
Segher
2015-05-10 Segher Boessenkool <segher@kernel.crashing.org>
* config/rs6000/rs6000.md (define_split for bswaphi): Don't use
zero_extract.
---
gcc/config/rs6000/rs6000.md | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
index acf890c..4bd16ee 100644
--- a/gcc/config/rs6000/rs6000.md
+++ b/gcc/config/rs6000/rs6000.md
@@ -2184,17 +2184,15 @@ (define_insn "bswaphi2_internal"
[(set_attr "length" "4,4,12")
(set_attr "type" "load,store,*")])
-;; We are always BITS_BIG_ENDIAN, so the (const_int 16) below is
-;; correct for -mlittle as well as -mbig.
(define_split
[(set (match_operand:HI 0 "gpc_reg_operand" "")
(bswap:HI (match_operand:HI 1 "gpc_reg_operand" "")))
(clobber (match_operand:SI 2 "gpc_reg_operand" ""))]
"reload_completed"
[(set (match_dup 3)
- (zero_extract:SI (match_dup 4)
- (const_int 8)
- (const_int 16)))
+ (and:SI (lshiftrt:SI (match_dup 4)
+ (const_int 8))
+ (const_int 255)))
(set (match_dup 2)
(and:SI (ashift:SI (match_dup 4)
(const_int 8))
--
1.8.1.4