go/test/prove_constant_folding.go
khr@golang.org 3b96eebcbd cmd/compile: rewrite the constant parts of the prove pass
Handles a lot more cases where constant ranges can eliminate
various (mostly bounds failure) paths.

Fixes #66826
Fixes #66692
Fixes #48213
Update #57959

TODO: remove constant logic from poset code, no longer needed.

Change-Id: Id196436fcd8a0c84c7d59c04f93bd92e26a0fd7e
Reviewed-on: https://go-review.googlesource.com/c/go/+/599096
Reviewed-by: David Chase <drchase@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
2024-08-07 16:07:33 +00:00

34 lines
654 B
Go

// errorcheck -0 -d=ssa/prove/debug=2
//go:build amd64
// Copyright 2022 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package main
func f0i(x int) int {
if x == 20 {
return x // ERROR "Proved.+is constant 20$"
}
if (x + 20) == 20 {
return x + 5 // ERROR "Proved.+is constant 0$" "Proved.+is constant 5$"
}
return x / 2
}
func f0u(x uint) uint {
if x == 20 {
return x // ERROR "Proved.+is constant 20$"
}
if (x + 20) == 20 {
return x + 5 // ERROR "Proved.+is constant 0$" "Proved.+is constant 5$"
}
return x / 2
}