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ec92bc6d63
Fixes #76332 Change-Id: I9044025d5dc599531c7f88ed2870bcf3d8b0acbd Reviewed-on: https://go-review.googlesource.com/c/go/+/721206 Reviewed-by: Mark Freeman <markfreeman@google.com> Reviewed-by: Keith Randall <khr@google.com> Auto-Submit: Jorropo <jorropo.pgm@gmail.com> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Keith Randall <khr@golang.org>
81 lines
1.8 KiB
Go
81 lines
1.8 KiB
Go
// errorcheck -0 -d=ssa/prove/debug=2
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//go:build amd64 || arm64
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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$"
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}
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if (x + 20) == 20 {
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return x + 5 // ERROR "Proved.+is constant 0$" "Proved.+is constant 5$" "x\+d >=? w"
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}
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return x + 1
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}
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func f0u(x uint) int {
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if x == 20 {
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return int(x) // ERROR "Proved.+is constant 20$"
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}
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if (x + 20) == 20 {
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return int(x + 5) // ERROR "Proved.+is constant 0$" "Proved.+is constant 5$" "x\+d >=? w"
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}
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if x < 1000 {
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return int(x) >> 31 // ERROR "(Proved.+is constant 0|Proved Rsh[0-9]+x[0-9]+ is unsigned)$"
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}
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if x := int32(x); x < -1000 {
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return int(x >> 31) // ERROR "Proved.+is constant -1$"
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}
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return int(x) + 1
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}
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// Check that prove is zeroing these right shifts of positive ints by bit-width - 1.
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// e.g (Rsh64x64 <t> n (Const64 <typ.UInt64> [63])) && ft.isNonNegative(n) -> 0
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func sh64(n int64) int64 {
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if n < 0 {
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return n
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}
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return n >> 63 // ERROR "(Proved .+ is constant 0|Proved Rsh[0-9]+x[0-9]+ is unsigned)$"
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}
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func sh32(n int32) int32 {
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if n < 0 {
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return n
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}
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return n >> 31 // ERROR "(Proved .+ is constant 0|Proved Rsh[0-9]+x[0-9]+ is unsigned)$"
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}
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func sh32x64(n int32) int32 {
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if n < 0 {
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return n
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}
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return n >> uint64(31) // ERROR "(Proved .+ is constant 0|Proved Rsh[0-9]+x[0-9]+ is unsigned)$"
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}
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func sh32x64n(n int32) int32 {
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if n >= 0 {
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return 0
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}
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return n >> 31 // ERROR "Proved .+ is constant -1$"
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}
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func sh16(n int16) int16 {
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if n < 0 {
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return n
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}
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return n >> 15 // ERROR "(Proved .+ is constant 0|Proved Rsh[0-9]+x[0-9]+ is unsigned)$"
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}
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func sh64noopt(n int64) int64 {
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return n >> 63 // not optimized; n could be negative
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}
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