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// asmcheck
// 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 codegen
import "runtime"
// This file contains code generation tests related to the use of the
// stack.
// Check that stack stores are optimized away.
// 386:"TEXT\t.*, [$]0-"
// amd64:"TEXT\t.*, [$]0-"
// arm:"TEXT\t.*, [$]-4-"
// arm64:"TEXT\t.*, [$]0-"
// mips:"TEXT\t.*, [$]-4-"
// ppc64x:"TEXT\t.*, [$]0-"
// s390x:"TEXT\t.*, [$]0-"
func StackStore() int {
var x int
return *(&x)
}
type T struct {
A, B, C, D int // keep exported fields
x, y, z int // reset unexported fields
}
// Check that large structs are cleared directly (issue #24416).
// 386:"TEXT\t.*, [$]0-"
// amd64:"TEXT\t.*, [$]0-"
// arm:"TEXT\t.*, [$]0-" (spills return address)
// arm64:"TEXT\t.*, [$]0-"
// mips:"TEXT\t.*, [$]-4-"
// ppc64x:"TEXT\t.*, [$]0-"
// s390x:"TEXT\t.*, [$]0-"
func ZeroLargeStruct(x *T) {
t := T{}
*x = t
}
// Check that structs are partially initialised directly (issue #24386).
// Notes:
// - 386 fails due to spilling a register
// amd64:"TEXT\t.*, [$]0-"
// arm:"TEXT\t.*, [$]0-" (spills return address)
// arm64:"TEXT\t.*, [$]0-"
// ppc64x:"TEXT\t.*, [$]0-"
// s390x:"TEXT\t.*, [$]0-"
// Note: that 386 currently has to spill a register.
func KeepWanted(t *T) {
*t = T{A: t.A, B: t.B, C: t.C, D: t.D}
}
// Check that small array operations avoid using the stack (issue #15925).
// Notes:
// - 386 fails due to spilling a register
// - arm & mips fail due to softfloat calls
// amd64:"TEXT\t.*, [$]0-"
// arm64:"TEXT\t.*, [$]0-"
// ppc64x:"TEXT\t.*, [$]0-"
// s390x:"TEXT\t.*, [$]0-"
func ArrayAdd64(a, b [4]float64) [4]float64 {
return [4]float64{a[0] + b[0], a[1] + b[1], a[2] + b[2], a[3] + b[3]}
}
// Check that small array initialization avoids using the stack.
// 386:"TEXT\t.*, [$]0-"
// amd64:"TEXT\t.*, [$]0-"
// arm:"TEXT\t.*, [$]0-" (spills return address)
// arm64:"TEXT\t.*, [$]0-"
// mips:"TEXT\t.*, [$]-4-"
// ppc64x:"TEXT\t.*, [$]0-"
// s390x:"TEXT\t.*, [$]0-"
func ArrayInit(i, j int) [4]int {
return [4]int{i, 0, j, 0}
}
// Check that assembly output has matching offset and base register
// (issue #21064).
func check_asmout(b [2]int) int {
runtime.GC() // use some frame
// amd64:`.*b\+24\(SP\)`
// arm:`.*b\+4\(FP\)`
return b[1]
}
// Check that simple functions get promoted to nosplit, even when
// they might panic in various ways. See issue 31219.
// amd64:"TEXT\t.*NOSPLIT.*"
func MightPanic(a []int, i, j, k, s int) {
_ = a[i] // panicIndex
_ = a[i:j] // panicSlice
_ = a[i:j:k] // also panicSlice
_ = i << s // panicShift
_ = i / j // panicDivide
}
// Put a defer in a loop, so second defer is not open-coded
func Defer() {
for i := 0; i < 2; i++ {
defer func() {}()
}
// amd64:`CALL\truntime\.deferprocStack`
defer func() {}()
}
// Check that stack slots are shared among values of the same
// type, but not pointer-identical types. See issue 65783.
func spillSlotReuse() {
// The return values of getp1 and getp2 need to be
// spilled around the calls to nopInt. Make sure that
// spill slot gets reused.
//arm64:`.*autotmp_2-8\(SP\)`
getp1()[nopInt()] = 0
//arm64:`.*autotmp_2-8\(SP\)`
getp2()[nopInt()] = 0
}
//go:noinline
func nopInt() int {
return 0
}
//go:noinline
func getp1() *[4]int {
return nil
}
//go:noinline
func getp2() *[4]int {
return nil
}
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