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cmd/compile: teach prove about and operation

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For this code:
z &= 63
_ = x<<z | x>>(64-z)
Now can prove 'x<<z' in bound. In ppc64 lowering pass, it will not
produce an extra '(ANDconst <typ.Int64> [63] z)' causing
codegen/rotate.go failed. Just remove the type check in rewrite rules
as the workaround.

Removes 32 bounds checks during make.bat.

Fixes #52563.

Change-Id: I14ed2c093ff5638dfea7de9bc7649c0f756dd71a
Reviewed-on: https://go-review.googlesource.com/c/go/+/404315
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: David Chase <drchase@google.com>
Auto-Submit: Keith Randall <khr@golang.org>
Run-TryBot: Wayne Zuo <wdvxdr@golangcn.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
This commit is contained in:
Wayne Zuo 2022-05-07 13:58:24 +08:00 • committed by Gopher Robot
parent 3391517c0e
commit 1efe38750a
4 changed files with 47 additions and 36 deletions
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3
src/cmd/compile/internal/ssa/prove.go
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@ -831,6 +831,9 @@ func prove(f *Func) {
case OpCtz64, OpCtz32, OpCtz16, OpCtz8, OpBitLen64, OpBitLen32, OpBitLen16, OpBitLen8:
ft.update(b, v, ft.zero, signed, gt|eq)
// TODO: we could also do <= 64/32/16/8, if that helped.
case OpAnd64, OpAnd32, OpAnd16, OpAnd8:
ft.update(b, v, v.Args[1], unsigned, lt|eq)
ft.update(b, v, v.Args[0], unsigned, lt|eq)
}
}
}