2bb808bfc2
Uniqued by LOC this adds 3 known bits hits when building the std. Updates #78633 Change-Id: I44f2ae1ed31f798d7881691729cce5d9707e8edc Reviewed-on: https://go-review.googlesource.com/c/go/+/766120 Reviewed-by: Keith Randall <khr@golang.org> Auto-Submit: Jorropo <jorropo.pgm@gmail.com> Reviewed-by: Mark Freeman <markfreeman@google.com> LUCI-TryBot-Result: golang-scoped@luci-project-accounts.iam.gserviceaccount.com <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Carlos Amedee <carlos@golang.org>
434 lines
8.0 KiB
Go
434 lines
8.0 KiB
Go
// errorcheck -0 -d=ssa/known_bits/debug=1
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//go:build amd64 || arm64 || s390x || ppc64le || riscv64
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// Copyright 2026 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 a
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func knownBitsPhiAnd(cond bool) int {
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x := 1
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if cond {
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x = 3
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}
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return x & 1 // ERROR "known value of v[0-9]+ \(And64\): 1$"
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}
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func knownBitsPhiAndGarbage(cond bool, x int) int {
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x &^= 1
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if cond {
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x = 2
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}
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return x & 1 // ERROR "known value of v[0-9]+ \(And64\): 0$"
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}
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func unknownBitsPhiAnd(cond bool) int {
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x := 1
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if cond {
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x = 2
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}
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return x & 1
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}
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func knownBitsOrGarbage(x, unknown int) int {
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x |= 7
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x |= unknown &^ 3
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return x & 3 // ERROR "known value of v[0-9]+ \(And64\): 3$"
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}
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func unknownBitsOrGarbage(x, unknown int) int {
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x |= 1
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x |= unknown
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return x & 3
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}
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func knownBitsDeferPattern(a, b bool) int {
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bits := 0
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bits |= 1 << 0
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if a {
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bits |= 1 << 1
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}
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bits |= 1 << 2
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if b {
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bits |= 1 << 3
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}
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return bits & (1<<2 | 1<<0) // ERROR "known value of v[0-9]+ \(And64\): 5$"
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}
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func knownBitsDeferPatternGarbage(a, b bool, garbage int) int {
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bits := 0
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bits |= 1 << 0
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if a {
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bits |= 1 << 1
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}
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bits |= 1 << 2
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if b {
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bits |= 1 << 3
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}
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bits ^= garbage &^ (1<<2 | 1<<0)
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return bits & (1<<2 | 1<<0) // ERROR "known value of v[0-9]+ \(And64\): 5$"
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}
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func knownBitsXorToggle(a, b, c bool) int {
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bits := 0
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bits ^= 1 << 0
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if a {
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bits ^= 1 << 1
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}
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bits ^= 1 << 2
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if b {
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bits ^= 1 << 3
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}
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bits ^= 1 << 2
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if c {
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bits ^= 1 << 4
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}
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return bits & (1<<2 | 1<<0) // ERROR "known value of v[0-9]+ \(And64\): 1$"
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}
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func knownBitsXorToggleGarbage(a, b, c bool, garbage int) int {
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bits := 0
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bits ^= 1 << 0
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if a {
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bits ^= 1 << 1
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}
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bits ^= 1 << 2
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if b {
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bits ^= 1 << 3
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}
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bits ^= 1 << 2
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if c {
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bits ^= 1 << 4
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}
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bits ^= garbage &^ (1<<2 | 1<<0)
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return bits & (1<<2 | 1<<0) // ERROR "known value of v[0-9]+ \(And64\): 1$"
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}
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func unknownBitsXorToggle(a, b, c bool) int {
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bits := 0
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bits ^= 1 << 0
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if a {
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bits ^= 1 << 1
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}
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bits ^= 1 << 2
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if b {
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bits ^= 1 << 2
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}
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bits ^= 1 << 2
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if c {
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bits ^= 1 << 4
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}
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return bits & (1<<2 | 1<<0)
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}
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func knownBitsPhiComAnd(cond bool) int {
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x := 1
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if cond {
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x = 3
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}
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return ^x & 1 // ERROR "known value of v[0-9]+ \(And64\): 0$"
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}
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func knownBitsPhiComAndGarbage(cond bool, garbage int) int {
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x := 1
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if cond {
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x = 3
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}
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x ^= garbage &^ 1
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return ^x & 1 // ERROR "known value of v[0-9]+ \(And64\): 0$"
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}
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func unknownBitsPhiComAnd(cond bool) int {
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x := 1
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if cond {
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x = 2
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}
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return ^x & 1
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}
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func knownBitsEqFalse(x, y uint64) bool {
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x |= 1
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y &^= 1
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return x == y // ERROR "known value of v[0-9]+ \(Eq64\): false$"
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}
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func knownBitsEqTrue(x uint64, cond bool) bool {
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x |= (1<<32 - 1) << 32
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if cond {
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x |= 42
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}
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x |= 1<<32 - 1 // ERROR "known value of v[0-9]+ \(Or64\): -1$"
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return x == 1<<64-1 // ERROR "known value of v[0-9]+ \(Eq64\): true$"
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}
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func unknownBitsEq(x, y uint64) bool {
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x |= 1
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return x == y
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}
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func knownBitsNeqTrue(x, y uint64) bool {
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x |= 1
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y &^= 1
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return x != y // ERROR "known value of v[0-9]+ \(Neq64\): true$"
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}
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func knownBitsNeqFalse(x uint64, cond bool) bool {
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x |= (1<<32 - 1) << 32
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if cond {
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x |= 42
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}
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x |= 1<<32 - 1
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return x != 1<<64-1 // ERROR "known value of v[0-9]+ \(Neq64\): false$"
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}
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func unknownBitsNeq(x, y uint64) bool {
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x |= 1
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return x != y
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}
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func knownBitsZeroExtPassThrough(x uint8) uint64 {
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x |= 6
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return uint64(x) & 6 // ERROR "known value of v[0-9]+ \(And64\): 6$"
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}
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func knownBitsZeroExtUpperHalf(x uint16) uint32 {
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return uint32(x) & 0xFFFF0000 // ERROR "known value of v[0-9]+ \(And32\): 0$"
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}
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func unknownBitsZeroExt(x uint16) uint32 {
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x |= 0xAAAA
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return uint32(x) & 0xFFFFF000
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}
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func cvtBoolToUint8(cond bool) (r uint8) {
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if cond {
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r = 1
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}
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return r
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}
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func knownBitsCvtBoolToUint8False(x, y uint64) uint8 {
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x |= 1
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y &^= 1
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bool := x == y // ERROR "known value of v[0-9]+ \(Eq64\): false$"
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return cvtBoolToUint8(bool) & 1 // ERROR "known value of v[0-9]+ \(CvtBoolToUint8\): 0$"
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}
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func knownBitsCvtBoolToUint8True(x int64, cond bool) uint8 {
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x |= 6
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if cond {
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x |= 1
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x |= 4
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}
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// I would expect "known value of v[0-9]+ \(And64\): 6$" to be required, but somehow it's not there even tho the AND is being folded.
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// I think it's an issue with the And's LOC meaning known bits prints it without a LOC and errorcheck skips it.
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r := cvtBoolToUint8(x&6 == 6) // ERROR "known value of v[0-9]+ \(Eq64\): true$" "known value of v[0-9]+ \(CvtBoolToUint8\): 1$"
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if cond {
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r |= 4 // ERROR "known value of v[0-9]+ \(Or8\): 5$"
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}
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return r & 3 // ERROR "known value of v[0-9]+ \(And8\): 1$"
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}
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func unknownBitsCvtBoolToUint8(cond bool) uint8 {
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return cvtBoolToUint8(cond) & 1
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}
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func knownBitsSignExtPassThrough(x int8) int64 {
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x |= 6
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return int64(x) & 6 // ERROR "known value of v[0-9]+ \(And64\): 6$"
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}
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func knownBitsSignExtUpperHalf(x int16) int32 {
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x |= -1 << 15
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return int32(x) & (-1 << 16) // ERROR "known value of v[0-9]+ \(And32\): -65536$"
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}
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func unknownBitsSignExt(x int16) int32 {
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x |= -0b010101010101010
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return int32(x) & -1 << 12
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}
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func knownBitsLsh(x, y uint32) uint32 {
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x |= 0b11110
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x &^= 0b100000
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y &= 2
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// ???01111?
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// ?01111???
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// ---------
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// ????11???
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return (x << y) & 0b11000 // ERROR "known value of v[0-9]+ \(And32\): 24$"
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}
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func knownBitsLshZero(x, y uint64) uint64 {
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x &^= 2
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y &^= 2
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y |= 128
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return (x << y) & 8 // ERROR "known value of v[0-9]+ \(And64\): 0$" "known value of v[0-9]+ \(Lsh64x[0-9]+\): 0$"
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}
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func unknownBitsLshLeftSideMsb(x uint32, y uint32) uint32 {
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x |= 0b11110
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x &^= 0b100000
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y &= 2
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return (x << y) & 0b111000
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}
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func unknownBitsLshLeftSideLsb(x uint32, y uint32) uint32 {
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x |= 0b11110
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x &^= 0b100000
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y &= 2
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return (x << y) & 0b011100
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}
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func unknownBitsLshRightSide(x uint32, y uint32) uint32 {
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x |= 0b11110
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x &^= 0b100000
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y &= 6
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return (x << y) & 0b11000
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}
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func knownBitsRshU(x, y uint32) uint32 {
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x |= 0b11110
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x &^= 0b100000
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y &= 2
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// ?01111?
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// ???0111
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// -------
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// ????11?
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return (x >> y) & 0b110 // ERROR "known value of v[0-9]+ \(And32\): 6$"
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}
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func knownBitsRshUZero(x, y uint64) uint64 {
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x &^= 4
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y &^= 2
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y |= 128
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return (x >> y) & 1 // ERROR "known value of v[0-9]+ \(And64\): 0$" "known value of v[0-9]+ \(Rsh64Ux[0-9]+\): 0$"
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}
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func unknownBitsRshULeftSideMsb(x uint32, y uint32) uint32 {
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x |= 0b11110
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x &^= 0b100000
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y &= 2
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return (x >> y) & 0b1110
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}
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func unknownBitsRshULeftSideLsb(x uint32, y uint32) uint32 {
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x |= 0b11110
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x &^= 0b100000
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y &= 2
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return (x >> y) & 0b111
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}
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func unknownBitsRshURightSide(x uint32, y uint32) uint32 {
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x |= 0b11110
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x &^= 0b100000
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y &= 6
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return (x >> y) & 0b110
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}
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func knownBitsRsh(x, y int32) int32 {
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x |= 0b11110
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x &^= 0b100000
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y &= 2
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// ?01111?
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// ???0111
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// -------
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// ????11?
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return (x >> y) & 0b110 // ERROR "known value of v[0-9]+ \(And32\): 6$"
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}
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func knownBitsRshSignCopy(x, y int64) int64 {
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x |= -1 << 63
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y |= 128
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return (x >> y) & 1 // ERROR "known value of v[0-9]+ \(And64\): 1$"
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}
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func unknownBitsRshLeftSideMsb(x int32, y int32) int32 {
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x |= 0b11110
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x &^= 0b100000
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y &= 2
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return (x >> y) & 0b1110
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}
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func unknownBitsRshLeftSideLsb(x int32, y int32) int32 {
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x |= 0b11110
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x &^= 0b100000
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y &= 2
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return (x >> y) & 0b111
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}
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func unknownBitsRshRightSide(x int32, y int32) int32 {
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x |= 0b11110
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x &^= 0b100000
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y &= 6
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return (x >> y) & 0b110
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}
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func knownBitsTrunc(x int64, cond bool) int32 {
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x |= 2
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if cond {
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x = 3
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}
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return int32(x) & 2 // ERROR "known value of v[0-9]+ \(And32\): 2$"
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}
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func unknownBitsTrunc(x int64, cond bool) int32 {
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x |= 2
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if cond {
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x = 3
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}
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return int32(x) & 1
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}
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func knownBitsSextAfterTrunc(x int64, cond1, cond2 bool) int64 {
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x |= -1 << 31
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if cond1 {
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x = -3
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}
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truncated := int32(x)
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if cond2 {
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truncated |= 4
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}
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return int64(truncated) & (-1 << 63) // ERROR "known value of v[0-9]+ \(And64\): -9223372036854775808$"
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}
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func unknownBitsSextAfterTrunc(x int64, cond1, cond2 bool) int64 {
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x |= 2
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if cond1 {
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x = 3
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}
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truncated := int32(x)
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if cond2 {
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truncated |= 4
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}
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return int64(truncated) & (-1 << 63)
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}
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