diff --git a/src/cmd/compile/internal/gc/asm_test.go b/src/cmd/compile/internal/gc/asm_test.go index 8eb3d07f2c..50857e6533 100644 --- a/src/cmd/compile/internal/gc/asm_test.go +++ b/src/cmd/compile/internal/gc/asm_test.go @@ -1002,6 +1002,20 @@ var linuxAMD64Tests = []*asmTest{ }`, pos: []string{"\tCMPL\t[A-Z]"}, }, + { + fn: ` + func $(a,b [3]int16) bool { + return a == b + }`, + pos: []string{"\tCMPL\t[A-Z]"}, + }, + { + fn: ` + func $(a,b [12]int8) bool { + return a == b + }`, + pos: []string{"\tCMPQ\t[A-Z]", "\tCMPL\t[A-Z]"}, + }, { fn: ` func f70(a,b [15]byte) bool { diff --git a/src/cmd/compile/internal/gc/walk.go b/src/cmd/compile/internal/gc/walk.go index 34c73acce0..f48513dc73 100644 --- a/src/cmd/compile/internal/gc/walk.go +++ b/src/cmd/compile/internal/gc/walk.go @@ -3415,18 +3415,23 @@ func walkcompare(n *Node, init *Nodes) *Node { i++ remains -= t.Elem().Width } else { + elemType := t.Elem().ToUnsigned() cmplw := nod(OINDEX, cmpl, nodintconst(int64(i))) - cmplw = conv(cmplw, convType) + cmplw = conv(cmplw, elemType) // convert to unsigned + cmplw = conv(cmplw, convType) // widen cmprw := nod(OINDEX, cmpr, nodintconst(int64(i))) + cmprw = conv(cmprw, elemType) cmprw = conv(cmprw, convType) // For code like this: uint32(s[0]) | uint32(s[1])<<8 | uint32(s[2])<<16 ... // ssa will generate a single large load. for offset := int64(1); offset < step; offset++ { lb := nod(OINDEX, cmpl, nodintconst(int64(i+offset))) + lb = conv(lb, elemType) lb = conv(lb, convType) lb = nod(OLSH, lb, nodintconst(int64(8*t.Elem().Width*offset))) cmplw = nod(OOR, cmplw, lb) rb := nod(OINDEX, cmpr, nodintconst(int64(i+offset))) + rb = conv(rb, elemType) rb = conv(rb, convType) rb = nod(OLSH, rb, nodintconst(int64(8*t.Elem().Width*offset))) cmprw = nod(OOR, cmprw, rb) diff --git a/test/fixedbugs/issue23719.go b/test/fixedbugs/issue23719.go new file mode 100644 index 0000000000..c97e63636c --- /dev/null +++ b/test/fixedbugs/issue23719.go @@ -0,0 +1,42 @@ +// run + +// Copyright 2018 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 main() { + v1 := [2]int32{-1, 88} + v2 := [2]int32{-1, 99} + if v1 == v2 { + panic("bad comparison") + } + + w1 := [2]int16{-1, 88} + w2 := [2]int16{-1, 99} + if w1 == w2 { + panic("bad comparison") + } + x1 := [4]int16{-1, 88, 88, 88} + x2 := [4]int16{-1, 99, 99, 99} + if x1 == x2 { + panic("bad comparison") + } + + a1 := [2]int8{-1, 88} + a2 := [2]int8{-1, 99} + if a1 == a2 { + panic("bad comparison") + } + b1 := [4]int8{-1, 88, 88, 88} + b2 := [4]int8{-1, 99, 99, 99} + if b1 == b2 { + panic("bad comparison") + } + c1 := [8]int8{-1, 88, 88, 88, 88, 88, 88, 88} + c2 := [8]int8{-1, 99, 99, 99, 99, 99, 99, 99} + if c1 == c2 { + panic("bad comparison") + } +}