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7f1c4b3afb
A Select Op could produce a value with upper 32 bits NOT zeroed, for example, Div32 is lowered to (Select0 (DIVL x y)). In theory, we could look into the argument of a Select to decide whether the upper bits are zeroed. As it is late in release cycle, just disable this optimization for Select for now. Fixes #23305. Change-Id: Icf665a2af9ccb0a7ba0ae00c683c9e349638bf85 Reviewed-on: https://go-review.googlesource.com/85736 Run-TryBot: Cherry Zhang <cherryyz@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Matthew Dempsky <mdempsky@google.com> Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
29 lines
575 B
Go
29 lines
575 B
Go
// run
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// Copyright 2018 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package main
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func mask1(a, b uint64) uint64 {
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op1 := int32(a)
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op2 := int32(b)
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return uint64(uint32(op1 / op2))
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}
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var mask2 = mask1
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func main() {
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res1 := mask1(0x1, 0xfffffffeffffffff)
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res2 := mask2(0x1, 0xfffffffeffffffff)
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if res1 != 0xffffffff {
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println("got", res1, "want", 0xffffffff)
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panic("FAIL")
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}
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if res2 != 0xffffffff {
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println("got", res2, "want", 0xffffffff)
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panic("FAIL")
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}
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}
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