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| author | Cuong Manh Le <cuong.manhle.vn@gmail.com> | 2020-10-24 10:40:09 +0700 |
|---|---|---|
| committer | Cuong Manh Le <cuong.manhle.vn@gmail.com> | 2020-10-27 03:11:45 +0000 |
| commit | a19cf510af8182751fefc16ce962f91fe17c1e1b (patch) | |
| tree | 20e7b93b381a5ce33e088748be8a90fd04e06462 /test | |
| parent | fb7134e4e3a45fee4ab662ef0d467ef864c23e2e (diff) | |
| download | go-a19cf510af8182751fefc16ce962f91fe17c1e1b.tar.gz go-a19cf510af8182751fefc16ce962f91fe17c1e1b.zip | |
cmd/compile: defer lowering OANDNOT until SSA
Currently, "x &^ y" gets rewriten into "x & ^y" during walk. It adds
unnecessary complexity to other parts, which must aware about this.
Instead, we can just implement "&^" in the conversion to SSA, so "&^"
can be handled like other binary operators.
However, this CL does not pass toolstash-check. It seems that implements
"&^" in the conversion to SSA causes registers allocation change.
With the parent:
obj: 00212 (.../src/runtime/complex.go:47) MOVQ X0, AX
obj: 00213 (.../src/runtime/complex.go:47) BTRQ $63, AX
obj: 00214 (.../src/runtime/complex.go:47) MOVQ "".n(SP), CX
obj: 00215 (.../src/runtime/complex.go:47) MOVQ $-9223372036854775808, DX
obj: 00216 (.../src/runtime/complex.go:47) ANDQ DX, CX
obj: 00217 (.../src/runtime/complex.go:47) ORQ AX, CX
With this CL:
obj: 00212 (.../src/runtime/complex.go:47) MOVQ X0, AX
obj: 00213 (.../src/runtime/complex.go:47) BTRQ $63, AX
obj: 00214 (.../src/runtime/complex.go:47) MOVQ $-9223372036854775808, CX
obj: 00215 (.../src/runtime/complex.go:47) MOVQ "".n(SP), DX
obj: 00216 (.../src/runtime/complex.go:47) ANDQ CX, DX
obj: 00217 (.../src/runtime/complex.go:47) ORQ AX, DX
Change-Id: I80acf8496a91be4804fb7ef3df04c19baae2754c
Reviewed-on: https://go-review.googlesource.com/c/go/+/264660
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Diffstat (limited to 'test')
| -rw-r--r-- | test/bounds.go | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/test/bounds.go b/test/bounds.go index 4a9c3b2d39..aa1d51b6f9 100644 --- a/test/bounds.go +++ b/test/bounds.go @@ -209,6 +209,11 @@ func main() { use(a1k[i&^0]) use(a1k[i&^-2]) // ERROR "index bounds check elided" use(a1k[i&^1]) + use(a1k[i8&^0]) + use(a1k[i8&^-128]) // ERROR "index bounds check elided" + use(a1k[ui8&^1]) // ERROR "index bounds check elided" + use(a1k[ui16&^0xf000]) + use(a1k[ui16&^0xff00]) // ERROR "index bounds check elided" // Right shift cuts the effective number of bits in the index, // but only for unsigned (signed stays negative). |