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| author | Ben Shi <powerman1st@163.com> | 2019-08-02 02:20:38 +0000 |
|---|---|---|
| committer | Brad Fitzpatrick <bradfitz@golang.org> | 2019-08-28 15:41:58 +0000 |
| commit | 3cfd003a8a89c6662b4b63d837a8cfae95e6762a (patch) | |
| tree | 6df2765928100a13e6e1f01d8335c1e865f08ac6 /test/codegen/mathbits.go | |
| parent | c683ab8128e3d26a9894f315793b32fb80e4b5b3 (diff) | |
| download | go-3cfd003a8a89c6662b4b63d837a8cfae95e6762a.tar.xz | |
cmd/compile: optimize ARM's math.bits.RotateLeft32
This CL optimizes math.bits.RotateLeft32 to inline
"MOVW Rx@>Ry, Rd" on ARM.
The benchmark results of math/bits show some improvements.
name old time/op new time/op delta
RotateLeft-4 9.42ns ± 0% 6.91ns ± 0% -26.66% (p=0.000 n=40+33)
RotateLeft8-4 8.79ns ± 0% 8.79ns ± 0% -0.04% (p=0.000 n=40+31)
RotateLeft16-4 8.79ns ± 0% 8.79ns ± 0% -0.04% (p=0.000 n=40+32)
RotateLeft32-4 8.16ns ± 0% 7.54ns ± 0% -7.68% (p=0.000 n=40+40)
RotateLeft64-4 15.7ns ± 0% 15.7ns ± 0% ~ (all equal)
updates #31265
Change-Id: I77bc1c2c702d5323fc7cad5264a8e2d5666bf712
Reviewed-on: https://go-review.googlesource.com/c/go/+/188697
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Diffstat (limited to 'test/codegen/mathbits.go')
| -rw-r--r-- | test/codegen/mathbits.go | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/test/codegen/mathbits.go b/test/codegen/mathbits.go index 0d94bd1bc8..ea90e3a50e 100644 --- a/test/codegen/mathbits.go +++ b/test/codegen/mathbits.go @@ -208,6 +208,7 @@ func RotateLeft64(n uint64) uint64 { func RotateLeft32(n uint32) uint32 { // amd64:"ROLL" 386:"ROLL" + // arm:`MOVW\tR[0-9]+@>[$]23` // arm64:"RORW" // ppc64:"ROTLW" // ppc64le:"ROTLW" @@ -244,6 +245,7 @@ func RotateLeftVariable64(n uint64, m int) uint64 { } func RotateLeftVariable32(n uint32, m int) uint32 { + // arm:`MOVW\tR[0-9]+@>R[0-9]+` // amd64:"ROLL" // arm64:"RORW" // ppc64:"ROTLW" |