Josh Bleecher Snyder
54dbab5221
cmd/compile: optimize TrailingZeros(8|16) on amd64
...
Introduce Ctz8 and Ctz16 ops and provide optimized lowerings for them.
amd64 only for this CL, although it wouldn't surprise me
if other architectures also admit of optimized lowerings.
name old time/op new time/op delta
TrailingZeros8-8 1.33ns ± 6% 0.84ns ± 3% -36.90% (p=0.000 n=20+20)
TrailingZeros16-8 1.26ns ± 5% 0.84ns ± 5% -33.50% (p=0.000 n=20+18)
Code:
func f8(x uint8) { z = bits.TrailingZeros8(x) }
func f16(x uint16) { z = bits.TrailingZeros16(x) }
Before:
"".f8 STEXT nosplit size=34 args=0x8 locals=0x0
0x0000 00000 (x.go:7) TEXT "".f8(SB), NOSPLIT, $0-8
0x0000 00000 (x.go:7) FUNCDATA $0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
0x0000 00000 (x.go:7) FUNCDATA $1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
0x0000 00000 (x.go:7) MOVBLZX "".x+8(SP), AX
0x0005 00005 (x.go:7) MOVBLZX AL, AX
0x0008 00008 (x.go:7) BTSQ $8, AX
0x000d 00013 (x.go:7) BSFQ AX, AX
0x0011 00017 (x.go:7) MOVL $64, CX
0x0016 00022 (x.go:7) CMOVQEQ CX, AX
0x001a 00026 (x.go:7) MOVQ AX, "".z(SB)
0x0021 00033 (x.go:7) RET
"".f16 STEXT nosplit size=34 args=0x8 locals=0x0
0x0000 00000 (x.go:8) TEXT "".f16(SB), NOSPLIT, $0-8
0x0000 00000 (x.go:8) FUNCDATA $0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
0x0000 00000 (x.go:8) FUNCDATA $1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
0x0000 00000 (x.go:8) MOVWLZX "".x+8(SP), AX
0x0005 00005 (x.go:8) MOVWLZX AX, AX
0x0008 00008 (x.go:8) BTSQ $16, AX
0x000d 00013 (x.go:8) BSFQ AX, AX
0x0011 00017 (x.go:8) MOVL $64, CX
0x0016 00022 (x.go:8) CMOVQEQ CX, AX
0x001a 00026 (x.go:8) MOVQ AX, "".z(SB)
0x0021 00033 (x.go:8) RET
After:
"".f8 STEXT nosplit size=20 args=0x8 locals=0x0
0x0000 00000 (x.go:7) TEXT "".f8(SB), NOSPLIT, $0-8
0x0000 00000 (x.go:7) FUNCDATA $0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
0x0000 00000 (x.go:7) FUNCDATA $1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
0x0000 00000 (x.go:7) MOVBLZX "".x+8(SP), AX
0x0005 00005 (x.go:7) BTSL $8, AX
0x0009 00009 (x.go:7) BSFL AX, AX
0x000c 00012 (x.go:7) MOVQ AX, "".z(SB)
0x0013 00019 (x.go:7) RET
"".f16 STEXT nosplit size=20 args=0x8 locals=0x0
0x0000 00000 (x.go:8) TEXT "".f16(SB), NOSPLIT, $0-8
0x0000 00000 (x.go:8) FUNCDATA $0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
0x0000 00000 (x.go:8) FUNCDATA $1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
0x0000 00000 (x.go:8) MOVWLZX "".x+8(SP), AX
0x0005 00005 (x.go:8) BTSL $16, AX
0x0009 00009 (x.go:8) BSFL AX, AX
0x000c 00012 (x.go:8) MOVQ AX, "".z(SB)
0x0013 00019 (x.go:8) RET
Change-Id: I0551e357348de2b724737d569afd6ac9f5c3aa11
Reviewed-on: https://go-review.googlesource.com/108940
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Keith Randall <khr@golang.org>
2018-04-25 21:33:52 +00:00
Giovanni Bajo
79112707bb
cmd/compile: add patterns for bit set/clear/complement on amd64
...
This patch completes implementation of BT(Q|L), and adds support
for BT(S|R|C)(Q|L).
Example of code changes from time.(*Time).addSec:
if t.wall&hasMonotonic != 0 {
0x1073465 488b08 MOVQ 0(AX), CX
0x1073468 4889ca MOVQ CX, DX
0x107346b 48c1e93f SHRQ $0x3f, CX
0x107346f 48c1e13f SHLQ $0x3f, CX
0x1073473 48f7c1ffffffff TESTQ $-0x1, CX
0x107347a 746b JE 0x10734e7
if t.wall&hasMonotonic != 0 {
0x1073435 488b08 MOVQ 0(AX), CX
0x1073438 480fbae13f BTQ $0x3f, CX
0x107343d 7363 JAE 0x10734a2
Another example:
t.wall = t.wall&nsecMask | uint64(dsec)<<nsecShift | hasMonotonic
0x10734c8 4881e1ffffff3f ANDQ $0x3fffffff, CX
0x10734cf 48c1e61e SHLQ $0x1e, SI
0x10734d3 4809ce ORQ CX, SI
0x10734d6 48b90000000000000080 MOVQ $0x8000000000000000, CX
0x10734e0 4809f1 ORQ SI, CX
0x10734e3 488908 MOVQ CX, 0(AX)
t.wall = t.wall&nsecMask | uint64(dsec)<<nsecShift | hasMonotonic
0x107348b 4881e2ffffff3f ANDQ $0x3fffffff, DX
0x1073492 48c1e61e SHLQ $0x1e, SI
0x1073496 4809f2 ORQ SI, DX
0x1073499 480fbaea3f BTSQ $0x3f, DX
0x107349e 488910 MOVQ DX, 0(AX)
Go1 benchmarks seem unaffected, and I would be surprised
otherwise:
name old time/op new time/op delta
BinaryTree17-4 2.64s ± 4% 2.56s ± 9% -2.92% (p=0.008 n=9+9)
Fannkuch11-4 2.90s ± 1% 2.95s ± 3% +1.76% (p=0.010 n=10+9)
FmtFprintfEmpty-4 35.3ns ± 1% 34.5ns ± 2% -2.34% (p=0.004 n=9+8)
FmtFprintfString-4 57.0ns ± 1% 58.4ns ± 5% +2.52% (p=0.029 n=9+10)
FmtFprintfInt-4 59.8ns ± 3% 59.8ns ± 6% ~ (p=0.565 n=10+10)
FmtFprintfIntInt-4 93.9ns ± 3% 91.2ns ± 5% -2.94% (p=0.014 n=10+9)
FmtFprintfPrefixedInt-4 107ns ± 6% 104ns ± 6% ~ (p=0.099 n=10+10)
FmtFprintfFloat-4 187ns ± 3% 188ns ± 3% ~ (p=0.505 n=10+9)
FmtManyArgs-4 410ns ± 1% 415ns ± 6% ~ (p=0.649 n=8+10)
GobDecode-4 5.30ms ± 3% 5.27ms ± 3% ~ (p=0.436 n=10+10)
GobEncode-4 4.62ms ± 5% 4.47ms ± 2% -3.24% (p=0.001 n=9+10)
Gzip-4 197ms ± 4% 193ms ± 3% ~ (p=0.123 n=10+10)
Gunzip-4 30.4ms ± 3% 30.1ms ± 3% ~ (p=0.481 n=10+10)
HTTPClientServer-4 76.3µs ± 1% 76.0µs ± 1% ~ (p=0.236 n=8+9)
JSONEncode-4 10.5ms ± 9% 10.3ms ± 3% ~ (p=0.280 n=10+10)
JSONDecode-4 42.3ms ±10% 41.3ms ± 2% ~ (p=0.053 n=9+10)
Mandelbrot200-4 3.80ms ± 2% 3.72ms ± 2% -2.15% (p=0.001 n=9+10)
GoParse-4 2.88ms ±10% 2.81ms ± 2% ~ (p=0.247 n=10+10)
RegexpMatchEasy0_32-4 69.5ns ± 4% 68.6ns ± 2% ~ (p=0.171 n=10+10)
RegexpMatchEasy0_1K-4 165ns ± 3% 162ns ± 3% ~ (p=0.137 n=10+10)
RegexpMatchEasy1_32-4 65.7ns ± 6% 64.4ns ± 2% -2.02% (p=0.037 n=10+10)
RegexpMatchEasy1_1K-4 278ns ± 2% 279ns ± 3% ~ (p=0.991 n=8+9)
RegexpMatchMedium_32-4 99.3ns ± 3% 98.5ns ± 4% ~ (p=0.457 n=10+9)
RegexpMatchMedium_1K-4 30.1µs ± 1% 30.4µs ± 2% ~ (p=0.173 n=8+10)
RegexpMatchHard_32-4 1.40µs ± 2% 1.41µs ± 4% ~ (p=0.565 n=10+10)
RegexpMatchHard_1K-4 42.5µs ± 1% 41.5µs ± 3% -2.13% (p=0.002 n=8+9)
Revcomp-4 332ms ± 4% 328ms ± 5% ~ (p=0.720 n=9+10)
Template-4 48.3ms ± 2% 49.6ms ± 3% +2.56% (p=0.002 n=8+10)
TimeParse-4 252ns ± 2% 249ns ± 3% ~ (p=0.116 n=9+10)
TimeFormat-4 262ns ± 4% 252ns ± 3% -4.01% (p=0.000 n=9+10)
name old speed new speed delta
GobDecode-4 145MB/s ± 3% 146MB/s ± 3% ~ (p=0.436 n=10+10)
GobEncode-4 166MB/s ± 5% 172MB/s ± 2% +3.28% (p=0.001 n=9+10)
Gzip-4 98.6MB/s ± 4% 100.4MB/s ± 3% ~ (p=0.123 n=10+10)
Gunzip-4 639MB/s ± 3% 645MB/s ± 3% ~ (p=0.481 n=10+10)
JSONEncode-4 185MB/s ± 8% 189MB/s ± 3% ~ (p=0.280 n=10+10)
JSONDecode-4 46.0MB/s ± 9% 47.0MB/s ± 2% +2.21% (p=0.046 n=9+10)
GoParse-4 20.1MB/s ± 9% 20.6MB/s ± 2% ~ (p=0.239 n=10+10)
RegexpMatchEasy0_32-4 460MB/s ± 4% 467MB/s ± 2% ~ (p=0.165 n=10+10)
RegexpMatchEasy0_1K-4 6.19GB/s ± 3% 6.28GB/s ± 3% ~ (p=0.165 n=10+10)
RegexpMatchEasy1_32-4 487MB/s ± 5% 497MB/s ± 2% +2.00% (p=0.043 n=10+10)
RegexpMatchEasy1_1K-4 3.67GB/s ± 2% 3.67GB/s ± 3% ~ (p=0.963 n=8+9)
RegexpMatchMedium_32-4 10.1MB/s ± 3% 10.1MB/s ± 4% ~ (p=0.435 n=10+9)
RegexpMatchMedium_1K-4 34.0MB/s ± 1% 33.7MB/s ± 2% ~ (p=0.173 n=8+10)
RegexpMatchHard_32-4 22.9MB/s ± 2% 22.7MB/s ± 4% ~ (p=0.565 n=10+10)
RegexpMatchHard_1K-4 24.0MB/s ± 3% 24.7MB/s ± 3% +2.64% (p=0.001 n=9+9)
Revcomp-4 766MB/s ± 4% 775MB/s ± 5% ~ (p=0.720 n=9+10)
Template-4 40.2MB/s ± 2% 39.2MB/s ± 3% -2.47% (p=0.002 n=8+10)
The rules match ~1800 times during all.bash.
Fixes #18943
Change-Id: I64be1ada34e89c486dfd935bf429b35652117ed4
Reviewed-on: https://go-review.googlesource.com/94766
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-24 02:38:50 +00:00
Alberto Donizetti
cde34780b7
test/codegen: port math/bits.RotateLeft tests to codegen
...
Only RotateLeft{64,32} were tested, and just for ppc64. This CL adds
tests for RotateLeft{64,32,16,8} on arm64 and amd64/386, for the cases
where the calls are actually instrinsified.
RotateLeft tests (the last ones for math/bits functions) are deleted
from asm_test.
This CL also adds a space between the "//" and the arch name in the
comments, to uniform this file to the style used in all the other
files.
Change-Id: Ifc2a27261d70bcc294b4ec64490d8367f62d2b89
Reviewed-on: https://go-review.googlesource.com/99596
Reviewed-by: Giovanni Bajo <rasky@develer.com>
2018-03-09 10:53:38 +00:00
