// Issue 26438: arm64 backend may use 64-bit TST for
// "if uint32(a)&uint32(b) == 0", which should be
// 32-bit TSTW

package main

//go:noinline
func tstw(a, b uint64) uint64 {
	if uint32(a)&uint32(b) == 0 {
		return 100
	} else {
		return 200
	}
}

func main() {
	if tstw(0xff00000000, 0xaa00000000) == 200 {
		panic("impossible")
	}

(XORconst [c] x) && !isARM64bitcon(uint64(c))  => (XOR x (MOVDconst [c]))
(TSTconst [c] x) && !isARM64bitcon(uint64(c))  => (TST x (MOVDconst [c]))
(TSTWconst [c] x) && !isARM64bitcon(uint64(c)|uint64(c)<<32)  => (TSTW x (MOVDconst [int64(c)]))

(CMPconst [c] x) && !isARM64addcon(c)  => (CMP x (MOVDconst [c]))
(CMPWconst [c] x) && !isARM64addcon(int64(c))  => (CMPW x (MOVDconst [int64(c)]))

	"SWPH",
	"SWPLB",
	"SWPLD",
	"SWPLH",
	"SWPLW",
	"SWPW",
	"SXTB",
	"SXTBW",
	"SXTH",
	"SXTHW",
	"SXTW",
	"SYS",
	"SYSL",
	"TBNZ",
	"TBZ",
	"TLBI",
	"TST",
	"TSTW",
	"UBFIZ",
	"UBFIZW",
	"UBFM",
	"UBFMW",
	"UBFX",
	"UBFXW",
	"UCVTFD",
	"UCVTFS",
	"UCVTFWD",
	"UCVTFWS",
	"UDIV",
	"UDIVW",
	"UMADDL",
	"UMNEGL",
	"UMSUBL",

	TSTW	$0x60060, R5                        // TSTW	$393312, R5                     // 1b0c8052db00a072bf001b6a
	TSTW	$0x6006000060060, R5                // TSTW	$1689262177517664, R5           // 1b0c8052db00a072bf001b6a
	ANDW	$0x6006000060060, R5                // ANDW	$1689262177517664, R5           // 1b0c8052db00a072a5001b0a

	c4 := e+f < 0
	// not optimized to single CMNW/CMN due to further use of b+d
	// arm64:`ADD`,-`CMNW`
	// arm:`ADD`,-`CMN`
	c5 := b+d == 0
	// not optimized to single TSTW/TST due to further use of a&d
	// arm64:`AND`,-`TSTW`
	// arm:`AND`,-`TST`
	// 386:`ANDL`
	c6 := a&d >= 0
	// arm64:`TST\sR[0-9]+<<3,\sR[0-9]+`
	c7 := e&(f<<3) < 0
	// arm64:`CMN\sR[0-9]+<<3,\sR[0-9]+`
	c8 := e+(f<<3) < 0

	SYSL $285440, R12                          // 0c5b2cd5
	TLBI VAE1IS, R1                            // 218308d5
	TSTW $0x80000007, R9                       // TSTW $2147483655, R9          // 3f0d0172
	TST $0xfffffff0, LR                        // TST $4294967280, R30          // df6f7cf2
	TSTW R10@>21, R2                           // 5f54ca6a
	TST R17<<11, R24                           // 1f2f11ea

func rewriteValueARM64latelower_OpARM64TSTWconst(v *Value) bool {
	v_0 := v.Args[0]
	b := v.Block
	typ := &b.Func.Config.Types
	// match: (TSTWconst [c] x)
	// cond: !isARM64bitcon(uint64(c)|uint64(c)<<32)
	// result: (TSTW x (MOVDconst [int64(c)]))
	for {
		c := auxIntToInt32(v.AuxInt)
		x := v_0
		if !(!isARM64bitcon(uint64(c) | uint64(c)<<32)) {
			break
		}
		v.reset(OpARM64TSTW)

		{name: "TSTconst", argLength: 1, reg: gp1flags, asm: "TST", aux: "Int64", typ: "Flags"},   // arg0 & auxInt compare to 0
		{name: "TSTW", argLength: 2, reg: gp2flags, asm: "TSTW", typ: "Flags", commutative: true}, // arg0 & arg1 compare to 0, 32 bit
		{name: "TSTWconst", argLength: 1, reg: gp1flags, asm: "TSTW", aux: "Int32", typ: "Flags"}, // arg0 & auxInt compare to 0, 32 bit

(FCMPS (FMOVSconst [0]) x) => (InvertFlags (FCMPS0 x))
(FCMPD x (FMOVDconst [0])) => (FCMPD0 x)
(FCMPD (FMOVDconst [0]) x) => (InvertFlags (FCMPD0 x))

// CSEL needs a flag-generating argument. Synthesize a TSTW if necessary.
(CondSelect x y boolval) && flagArg(boolval) != nil => (CSEL [boolval.Op] x y flagArg(boolval))
(CondSelect x y boolval) && flagArg(boolval) == nil => (CSEL [OpARM64NotEqual] x y (TSTWconst [1] boolval))

		v0.AuxInt = int32ToAuxInt(int32(c))
		v0.AddArg(y)
		v.AddArg(v0)
		return true
	}
	// match: (Equal (CMPWconst [0] z:(AND x y)))
	// cond: z.Uses == 1
	// result: (Equal (TSTW x y))
	for {
		if v_0.Op != OpARM64CMPWconst || auxIntToInt32(v_0.AuxInt) != 0 {
			break
		}
		z := v_0.Args[0]
		if z.Op != OpARM64AND {
			break
		}
		y := z.Args[1]
		x := z.Args[0]