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| author | ruinan <ruinan.sun@arm.com> | 2022-07-13 09:00:57 +0000 |
|---|---|---|
| committer | Gopher Robot <gobot@golang.org> | 2022-09-02 17:46:31 +0000 |
| commit | 121344ac338ef21d87eee4f64a60d0ae8a7f6fe3 (patch) | |
| tree | a01377bbbb4aa9f6c8401eee8277412d8062d249 /test/codegen/mathbits.go | |
| parent | f45c2d7e47e6dcfb69876092037257562813cc37 (diff) | |
| download | go-121344ac338ef21d87eee4f64a60d0ae8a7f6fe3.tar.xz | |
cmd/compile: optimize RotateLeft8/16 on arm64
This CL optimizes RotateLeft8/16 on arm64.
For 16 bits, we form a 32 bits register by duplicating two 16 bits
registers, then use RORW instruction to do the rotate shift.
For 8 bits, we just use LSR and LSL instead of RORW because the code is
simpler.
Benchmark Old ThisCL delta
RotateLeft8-46 2.16 ns/op 1.73 ns/op -19.70%
RotateLeft16-46 2.16 ns/op 1.54 ns/op -28.53%
Change-Id: I09cde4383d12e31876a57f8cdfd3bb4f324fadb0
Reviewed-on: https://go-review.googlesource.com/c/go/+/420976
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
Diffstat (limited to 'test/codegen/mathbits.go')
| -rw-r--r-- | test/codegen/mathbits.go | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/test/codegen/mathbits.go b/test/codegen/mathbits.go index 9c643647ee..0620766f5a 100644 --- a/test/codegen/mathbits.go +++ b/test/codegen/mathbits.go @@ -258,14 +258,16 @@ func RotateLeft32(n uint32) uint32 { return bits.RotateLeft32(n, 9) } -func RotateLeft16(n uint16) uint16 { +func RotateLeft16(n uint16, s int) uint16 { // amd64:"ROLW" 386:"ROLW" - return bits.RotateLeft16(n, 5) + // arm64:"RORW",-"CSEL" + return bits.RotateLeft16(n, s) } -func RotateLeft8(n uint8) uint8 { +func RotateLeft8(n uint8, s int) uint8 { // amd64:"ROLB" 386:"ROLB" - return bits.RotateLeft8(n, 5) + // arm64:"LSL","LSR",-"CSEL" + return bits.RotateLeft8(n, s) } func RotateLeftVariable(n uint, m int) uint { |