// clobber generates code to clobber pointer slots in all dead variables
// (those not marked in live). Clobbering instructions are added to the end
// of b.Values.
func clobber(lv *liveness, b *ssa.Block, live bitvec.BitVec) {
	for i, n := range lv.vars {
		if !live.Get(int32(i)) && !n.Addrtaken() && !n.OpenDeferSlot() && !n.IsOutputParamHeapAddr() {
			// Don't clobber stack objects (address-taken). They are
			// tracked dynamically.

package codegen

type T [2]*int // contain pointer, not SSA-able (so locals are not registerized)

var p1, p2, p3 T

func F() {
	// 3735936685 is 0xdeaddead. On ARM64 R27 is REGTMP.
	// clobber x, y at entry. not clobber z (stack object).
	// amd64:`MOVL\t\$3735936685, command-line-arguments\.x`, `MOVL\t\$3735936685, command-line-arguments\.y`, -`MOVL\t\$3735936685, command-line-arguments\.z`

	np uintptr
	x  [1023]int
}

var G int

//go:noinline
func clobber() {
	G++
}

func ABC(i, j int) int {
	r := 0

	// here v2 and v3 can be overlapped.
	clobber()
	if i < 101 {
		var v2 Vanilla
		v2.x[i] = j
		r += v2.x[j]
	}
	if j != 303 {
		var v3 Vanilla2
		v3.x[i] = j
		r += v3.x[j]
	}
	clobber()

	// not an overlap candidate (only one var of this size).
	var s Single

//go:build (mips64 || mips64le) && gc

#include "textflag.h"

#define SYNC	WORD $0xf

TEXT ·RewindAndSetgid(SB),NOSPLIT|NOFRAME,$0-0
	// Rewind stack pointer so anything that happens on the stack
	// will clobber the test pattern created by the caller
	ADDV	$(1024*8), R29

	// Ask signaller to setgid
	MOVW	$1, R1
	SYNC
	MOVW	R1, ·Baton(SB)
	SYNC

	// Wait for setgid completion
loop:
	SYNC

//go:build (amd64 || amd64p32) && gc

#include "textflag.h"

TEXT ·RewindAndSetgid(SB),NOSPLIT,$0-0
	// Rewind stack pointer so anything that happens on the stack
	// will clobber the test pattern created by the caller
	ADDQ	$(1024 * 8), SP

	// Ask signaller to setgid
	MOVL	$1, ·Baton(SB)

	// Wait for setgid completion
loop:
	PAUSE
	MOVL	·Baton(SB), AX
	CMPL	AX, $0
	JNE	loop

	MOVW	$0xffff0fc0, R15 // R15 is PC

TEXT ·RewindAndSetgid(SB),NOSPLIT|NOFRAME,$0-0
	// Save link register
	MOVW	R14, R4

	// Rewind stack pointer so anything that happens on the stack
	// will clobber the test pattern created by the caller
	ADD	$(1024 * 8), R13

	// Ask signaller to setgid
	MOVW	$·Baton(SB), R2
storeloop:
	MOVW	0(R2), R0
	MOVW	$1, R1
	BL	cas<>(SB)
	BCC	storeloop

(MOVBQZX x:(MOVBload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVBload <v.Type> [off] {sym} ptr mem)
(MOVBQZX x:(MOVWload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVBload <v.Type> [off] {sym} ptr mem)
(MOVBQZX x:(MOVLload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVBload <v.Type> [off] {sym} ptr mem)

// license that can be found in the LICENSE file.

//go:build riscv64 && gc

#include "textflag.h"

TEXT ·RewindAndSetgid(SB),NOSPLIT|NOFRAME,$0-0
	// Rewind stack pointer so anything that happens on the stack
	// will clobber the test pattern created by the caller
	ADD	$(1024*8), X2

	// Ask signaller to setgid
	MOV	$1, X5
	FENCE
	MOVW	X5, ·Baton(SB)
	FENCE

	// Wait for setgid completion
loop:
	FENCE

//go:build (mips || mipsle) && gc

#include "textflag.h"

TEXT ·RewindAndSetgid(SB),NOSPLIT|NOFRAME,$0-0
	// Rewind stack pointer so anything that happens on the stack
	// will clobber the test pattern created by the caller
	ADDU	$(1024*8), R29

	// Ask signaller to setgid
	MOVW	$1, R1
	SYNC
	MOVW	R1, ·Baton(SB)
	SYNC

	// Wait for setgid completion
loop:
	SYNC

//go:build (ppc64 || ppc64le) && gc

#include "textflag.h"

TEXT ·RewindAndSetgid(SB),NOSPLIT|NOFRAME,$0-0
	// Rewind stack pointer so anything that happens on the stack
	// will clobber the test pattern created by the caller
	ADD	$(1024 * 8), R1

	// Ask signaller to setgid
	MOVW	$1, R3
	SYNC
	MOVW	R3, ·Baton(SB)

	// Wait for setgid completion
loop:
	SYNC
	MOVW	·Baton(SB), R3