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| author | Junchen Li <junchen.li@arm.com> | 2020-07-10 11:39:23 +0800 |
|---|---|---|
| committer | Keith Randall <khr@golang.org> | 2020-08-17 20:06:35 +0000 |
| commit | e30fbe3757d09a22988835835c41233df7c6cd00 (patch) | |
| tree | e53cc3bf90165f2b72d849ba58045f7472d1d80a /test/codegen | |
| parent | 1a3558341860357c2400e37773e5076bb3a51628 (diff) | |
| download | go-e30fbe3757d09a22988835835c41233df7c6cd00.tar.gz go-e30fbe3757d09a22988835835c41233df7c6cd00.zip | |
cmd/compile: optimize unsigned comparisons to 0
There are some architecture-independent rules in #21439, since an
unsigned integer >= 0 is always true and < 0 is always false. This CL
adds these optimizations to generic rules.
Updates #21439
Change-Id: Iec7e3040b761ecb1e60908f764815fdd9bc62495
Reviewed-on: https://go-review.googlesource.com/c/go/+/246617
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Diffstat (limited to 'test/codegen')
| -rw-r--r-- | test/codegen/comparisons.go | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/test/codegen/comparisons.go b/test/codegen/comparisons.go index 90808573c2..f3c15538a8 100644 --- a/test/codegen/comparisons.go +++ b/test/codegen/comparisons.go @@ -407,3 +407,20 @@ func CmpToZero_ex5(e, f int32, u uint32) int { } return 0 } +func UintLtZero(a uint8, b uint16, c uint32, d uint64) int { + // amd64: -`(TESTB|TESTW|TESTL|TESTQ|JCC|JCS)` + // arm64: -`(CMPW|CMP|BHS|BLO)` + if a < 0 || b < 0 || c < 0 || d < 0 { + return 1 + } + return 0 +} + +func UintGeqZero(a uint8, b uint16, c uint32, d uint64) int { + // amd64: -`(TESTB|TESTW|TESTL|TESTQ|JCS|JCC)` + // arm64: -`(CMPW|CMP|BLO|BHS)` + if a >= 0 || b >= 0 || c >= 0 || d >= 0 { + return 1 + } + return 0 +} |