var thenList []syntax.Stmt
	if zeroNext {
		clr := &syntax.AssignStmt{
			Lhs: r.next(),
			Rhs: r.intConst(0),
		}
		thenList = append(thenList, clr)
	}
	for _, then := range thens {
		thenList = append(thenList, then)
	}
	nif := &syntax.IfStmt{
		Cond: r.cond(op, r.next(), r.intConst(c)),
		Then: &syntax.BlockStmt{
			List: thenList,
		},
	}
	return nif
}

	I64Const $8
	Call	gcWriteBarrier<>(SB)
	Return
TEXT runtime·gcWriteBarrier2<ABIInternal>(SB),NOSPLIT,$0
	I64Const $16
	Call	gcWriteBarrier<>(SB)
	Return
TEXT runtime·gcWriteBarrier3<ABIInternal>(SB),NOSPLIT,$0
	I64Const $24
	Call	gcWriteBarrier<>(SB)
	Return
TEXT runtime·gcWriteBarrier4<ABIInternal>(SB),NOSPLIT,$0
	I64Const $32
	Call	gcWriteBarrier<>(SB)
	Return

(SGTconst [c] (MOVBUreg _)) && 0xff < c => (MOVVconst [1])
(SGTconst [c] (MOVBUreg _)) && c < 0 => (MOVVconst [0])
(SGTUconst [c] (MOVBUreg _)) && 0xff < uint64(c) => (MOVVconst [1])
(SGTconst [c] (MOVHreg _)) && 0x7fff < c => (MOVVconst [1])
(SGTconst [c] (MOVHreg _)) && c <= -0x8000 => (MOVVconst [0])
(SGTconst [c] (MOVHUreg _)) && 0xffff < c => (MOVVconst [1])
(SGTconst [c] (MOVHUreg _)) && c < 0 => (MOVVconst [0])

(SGTconst [c] (MOVBUreg _)) && 0xff < c => (MOVVconst [1])
(SGTconst [c] (MOVBUreg _)) && c < 0 => (MOVVconst [0])
(SGTUconst [c] (MOVBUreg _)) && 0xff < uint64(c) => (MOVVconst [1])
(SGTconst [c] (MOVHreg _)) && 0x7fff < c => (MOVVconst [1])
(SGTconst [c] (MOVHreg _)) && c <= -0x8000 => (MOVVconst [0])
(SGTconst [c] (MOVHUreg _)) && 0xffff < c => (MOVVconst [1])
(SGTconst [c] (MOVHUreg _)) && c < 0 => (MOVVconst [0])

(ANDconst [c] (MOVDconst [d]))  => (MOVDconst [c&d])
(ANDconst [c] (ANDconst [d] x)) => (ANDconst [c&d] x)
(ANDconst [c] (MOVWUreg x)) => (ANDconst [c&(1<<32-1)] x)
(ANDconst [c] (MOVHUreg x)) => (ANDconst [c&(1<<16-1)] x)
(ANDconst [c] (MOVBUreg x)) => (ANDconst [c&(1<<8-1)] x)
(MOVWUreg (ANDconst [c] x)) => (ANDconst [c&(1<<32-1)] x)
(MOVHUreg (ANDconst [c] x)) => (ANDconst [c&(1<<16-1)] x)

(MOVHUreg x:(MOVHUload _ _)) => (MOVWreg x)

// fold extensions and ANDs together
(MOVBUreg (ANDconst [c] x)) => (ANDconst [c&0xff] x)
(MOVHUreg (ANDconst [c] x)) => (ANDconst [c&0xffff] x)
(MOVBreg (ANDconst [c] x)) && c & 0x80 == 0 => (ANDconst [c&0x7f] x)
(MOVHreg (ANDconst [c] x)) && c & 0x8000 == 0 => (ANDconst [c&0x7fff] x)

// fold double extensions
(MOVBreg x:(MOVBreg _)) => (MOVWreg x)

cui fliter <******@****.***> 1697288956 +0800

(SUBconst [c] x) && !isARM64addcon(c)  => (SUB x (MOVDconst [c]))
(ANDconst [c] x) && !isARM64bitcon(uint64(c)) => (AND x (MOVDconst [c]))
(ORconst  [c] x) && !isARM64bitcon(uint64(c))  => (OR  x (MOVDconst [c]))
(XORconst [c] x) && !isARM64bitcon(uint64(c))  => (XOR x (MOVDconst [c]))
(TSTconst [c] x) && !isARM64bitcon(uint64(c))  => (TST x (MOVDconst [c]))

	}
	newList := make([]ir.Node, 0, need)
	for i := 0; i < len(s); i++ {
		if ir.IsConst(s[i], constant.String) && i+1 < len(s) && ir.IsConst(s[i+1], constant.String) {
			// merge from i up to but not including i2
			var strs []string
			i2 := i
			for i2 < len(s) && ir.IsConst(s[i2], constant.String) {
				strs = append(strs, ir.StringVal(s[i2]))
				i2++
			}

	//  wasm:`I64Const\t\$12592`,`I64Store16\t\$0`,`I64Const\t\$50`,`I64Store8\t\$2`
	// mips64:`MOVV\t\$48`,`MOVV\t\$49`,`MOVV\t\$50`
	bsink = []byte("012")

	// 858927408 = 0x33323130
	//     13620 = 0x3534
	// amd64:`MOVL\t\$858927408`,`MOVW\t\$13620, 4\(`
	//   386:`MOVL\t\$858927408`,`MOVW\t\$13620, 4\(`
	// arm64:`MOVD\t\$858927408`,`MOVD\t\$13620`