cmd/compile: optimize ARMv7 code
"AND $0xffff0000, Rx" will be encoded to 12 bytes.
1. MOVWload from the constant pool to Rtmp
2. AND Rtmp, Rx
3. a 4-byte item in the constant pool
It can be simplified to 8 bytes on ARMv7, since ARMv7 has
"MOVW $imm-16, Rx".
1. MOVW $0xffff, Rtmp
2. BIC Rtmp, Rx
The above optimization also applies to BICconst, ADDconst and
SUBconst.
1. The total size of pkg/android_arm (excluding cmd/compile)
decreases about 2KB.
2. The go1 benchmark shows no regression, exlcuding noise.
name old time/op new time/op delta
BinaryTree17-4 25.5s ± 1% 25.2s ± 1% -0.85% (p=0.000 n=30+30)
Fannkuch11-4 13.3s ± 0% 13.3s ± 0% +0.16% (p=0.000 n=24+25)
FmtFprintfEmpty-4 397ns ± 0% 394ns ± 0% -0.64% (p=0.000 n=30+30)
FmtFprintfString-4 679ns ± 0% 678ns ± 0% ~ (p=0.093 n=30+29)
FmtFprintfInt-4 708ns ± 0% 707ns ± 0% -0.19% (p=0.000 n=27+28)
FmtFprintfIntInt-4 1.05µs ± 0% 1.05µs ± 0% -0.07% (p=0.001 n=18+30)
FmtFprintfPrefixedInt-4 1.16µs ± 0% 1.15µs ± 0% -0.41% (p=0.000 n=29+30)
FmtFprintfFloat-4 2.26µs ± 0% 2.23µs ± 1% -1.40% (p=0.000 n=30+30)
FmtManyArgs-4 3.96µs ± 0% 3.95µs ± 0% -0.29% (p=0.000 n=29+30)
GobDecode-4 52.9ms ± 2% 53.4ms ± 2% +0.92% (p=0.004 n=28+30)
GobEncode-4 49.7ms ± 2% 49.8ms ± 2% ~ (p=0.890 n=30+26)
Gzip-4 2.61s ± 0% 2.60s ± 0% -0.36% (p=0.000 n=29+29)
Gunzip-4 312ms ± 0% 311ms ± 0% -0.13% (p=0.000 n=30+28)
HTTPClientServer-4 1.02ms ± 8% 1.00ms ± 7% ~ (p=0.224 n=29+26)
JSONEncode-4 125ms ± 1% 124ms ± 3% -1.05% (p=0.000 n=25+30)
JSONDecode-4 432ms ± 1% 436ms ± 2% ~ (p=0.277 n=26+30)
Mandelbrot200-4 18.4ms ± 0% 18.4ms ± 0% +0.02% (p=0.001 n=28+25)
GoParse-4 22.4ms ± 1% 22.3ms ± 1% -0.41% (p=0.000 n=28+28)
RegexpMatchEasy0_32-4 697ns ± 0% 706ns ± 0% +1.23% (p=0.000 n=19+30)
RegexpMatchEasy0_1K-4 4.27µs ± 0% 4.26µs ± 0% -0.06% (p=0.000 n=30+30)
RegexpMatchEasy1_32-4 741ns ± 0% 735ns ± 0% -0.86% (p=0.000 n=26+30)
RegexpMatchEasy1_1K-4 5.49µs ± 0% 5.49µs ± 0% -0.03% (p=0.023 n=25+30)
RegexpMatchMedium_32-4 1.05µs ± 2% 1.04µs ± 2% ~ (p=0.893 n=30+30)
RegexpMatchMedium_1K-4 261µs ± 0% 261µs ± 0% -0.11% (p=0.000 n=29+30)
RegexpMatchHard_32-4 14.9µs ± 0% 14.9µs ± 0% -0.36% (p=0.000 n=23+29)
RegexpMatchHard_1K-4 446µs ± 0% 445µs ± 0% -0.17% (p=0.000 n=30+29)
Revcomp-4 41.6ms ± 1% 41.7ms ± 1% +0.27% (p=0.040 n=28+30)
Template-4 531ms ± 0% 532ms ± 1% ~ (p=0.059 n=30+30)
TimeParse-4 3.40µs ± 0% 3.33µs ± 0% -2.02% (p=0.000 n=30+30)
TimeFormat-4 6.14µs ± 0% 6.11µs ± 0% -0.45% (p=0.000 n=27+29)
[Geo mean] 384µs 383µs -0.27%
name old speed new speed delta
GobDecode-4 14.5MB/s ± 2% 14.4MB/s ± 2% -0.90% (p=0.005 n=28+30)
GobEncode-4 15.4MB/s ± 2% 15.4MB/s ± 2% ~ (p=0.741 n=30+25)
Gzip-4 7.44MB/s ± 0% 7.47MB/s ± 1% +0.37% (p=0.000 n=25+30)
Gunzip-4 62.3MB/s ± 0% 62.4MB/s ± 0% +0.13% (p=0.000 n=30+28)
JSONEncode-4 15.5MB/s ± 1% 15.6MB/s ± 3% +1.07% (p=0.000 n=25+30)
JSONDecode-4 4.48MB/s ± 0% 4.46MB/s ± 2% ~ (p=0.655 n=23+30)
GoParse-4 2.58MB/s ± 1% 2.59MB/s ± 1% +0.42% (p=0.000 n=28+29)
RegexpMatchEasy0_32-4 45.9MB/s ± 0% 45.3MB/s ± 0% -1.23% (p=0.000 n=28+30)
RegexpMatchEasy0_1K-4 240MB/s ± 0% 240MB/s ± 0% +0.07% (p=0.000 n=30+30)
RegexpMatchEasy1_32-4 43.2MB/s ± 0% 43.5MB/s ± 0% +0.85% (p=0.000 n=30+28)
RegexpMatchEasy1_1K-4 186MB/s ± 0% 186MB/s ± 0% +0.03% (p=0.026 n=25+30)
RegexpMatchMedium_32-4 955kB/s ± 2% 960kB/s ± 2% ~ (p=0.084 n=30+30)
RegexpMatchMedium_1K-4 3.92MB/s ± 0% 3.93MB/s ± 0% +0.14% (p=0.000 n=29+30)
RegexpMatchHard_32-4 2.14MB/s ± 0% 2.15MB/s ± 0% +0.31% (p=0.000 n=30+26)
RegexpMatchHard_1K-4 2.30MB/s ± 0% 2.30MB/s ± 0% ~ (all equal)
Revcomp-4 61.1MB/s ± 1% 60.9MB/s ± 1% -0.27% (p=0.039 n=28+30)
Template-4 3.66MB/s ± 0% 3.65MB/s ± 1% -0.14% (p=0.045 n=30+30)
[Geo mean] 12.8MB/s 12.8MB/s +0.04%
Change-Id: I02370e2584b4c041fddd324c97628fd6f0c12183
Reviewed-on: https://go-review.googlesource.com/123179
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>