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e1e056fa6a
It is hit ~70k times building go.
This make the go binary, 0.04% smaller.
I didn't included benchmarks because this is just constant foldings
and is hard to mesure objectively.
For example, this enable rewriting things like:
if x == 20 {
return x + 30 + z
}
Into:
if x == 20 {
return 50 + z
}
It's not just fixing programer's code,
the ssa generator generate code like this sometimes.
Change-Id: I0861f342b27f7227b5f1c34d8267fa0057b1bbbc
GitHub-Last-Rev: 4c2f9b521692bc61acff137a269917895f4da08a
GitHub-Pull-Request: golang/go#52669
Reviewed-on: https://go-review.googlesource.com/c/go/+/403735
Reviewed-by: Keith Randall <khr@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
33 lines
602 B
Go
33 lines
602 B
Go
// +build amd64
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// errorcheck -0 -d=ssa/prove/debug=2
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// Copyright 2022 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 f0i(x int) int {
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if x == 20 {
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return x // ERROR "Proved.+is constant 20$"
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}
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if (x + 20) == 20 {
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return x + 5 // ERROR "Proved.+is constant 0$"
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}
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return x / 2
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}
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func f0u(x uint) uint {
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if x == 20 {
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return x // ERROR "Proved.+is constant 20$"
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}
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if (x + 20) == 20 {
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return x + 5 // ERROR "Proved.+is constant 0$"
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}
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return x / 2
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}
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