Golang cmd-compile-avail-gc.Nodconst类(方法)实例源码

下面列出了Golang cmd-compile-avail-gc.Nodconst 类(方法)源码代码实例,从而了解它的用法。

作者:glycerin    项目:zygomy   
/*
 * generate
 *	as $c, n
 */
func ginscon(as obj.As, c int64, n2 *gc.Node) {
	var n1 gc.Node

	switch as {
	case x86.AADDL,
		x86.AMOVL,
		x86.ALEAL:
		gc.Nodconst(&n1, gc.Types[gc.TINT32], c)

	default:
		gc.Nodconst(&n1, gc.Types[gc.TINT64], c)
	}

	if as != x86.AMOVQ && (c < -(1<<31) || c >= 1<<31) {
		// cannot have 64-bit immediate in ADD, etc.
		// instead, MOV into register first.
		var ntmp gc.Node
		gc.Regalloc(&ntmp, gc.Types[gc.TINT64], nil)

		gins(x86.AMOVQ, &n1, &ntmp)
		gins(as, &ntmp, n2)
		gc.Regfree(&ntmp)
		return
	}

	gins(as, &n1, n2)
}

作者:glycerin    项目:zygomy   
// RightShiftWithCarry generates a constant unsigned
// right shift with carry.
//
// res = n >> shift // with carry
func RightShiftWithCarry(n *gc.Node, shift uint, res *gc.Node) {
	// Extra 1 is for carry bit.
	maxshift := uint(n.Type.Width*8 + 1)
	if shift == 0 {
		gmove(n, res)
	} else if shift < maxshift {
		// 1. clear rightmost bit of target
		var n1 gc.Node
		gc.Nodconst(&n1, n.Type, 1)
		gins(optoas(gc.ORSH, n.Type), &n1, n)
		gins(optoas(gc.OLSH, n.Type), &n1, n)
		// 2. add carry flag to target
		var n2 gc.Node
		gc.Nodconst(&n1, n.Type, 0)
		gc.Regalloc(&n2, n.Type, nil)
		gins(optoas(gc.OAS, n.Type), &n1, &n2)
		gins(arm64.AADC, &n2, n)
		// 3. right rotate 1 bit
		gc.Nodconst(&n1, n.Type, 1)
		gins(arm64.AROR, &n1, n)

		// ARM64 backend doesn't eliminate shifts by 0. It is manually checked here.
		if shift > 1 {
			var n3 gc.Node
			gc.Nodconst(&n3, n.Type, int64(shift-1))
			cgen_shift(gc.ORSH, true, n, &n3, res)
		} else {
			gmove(n, res)
		}
		gc.Regfree(&n2)
	} else {
		gc.Fatalf("RightShiftWithCarry: shift(%v) is bigger than max size(%v)", shift, maxshift)
	}
}

作者:glycerin    项目:zygomy   
/*
 * n is a 64-bit value.  fill in lo and hi to refer to its 32-bit halves.
 */
func split64(n *gc.Node, lo *gc.Node, hi *gc.Node) {
	if !gc.Is64(n.Type) {
		gc.Fatalf("split64 %v", n.Type)
	}

	if nsclean >= len(sclean) {
		gc.Fatalf("split64 clean")
	}
	sclean[nsclean].Op = gc.OEMPTY
	nsclean++
	switch n.Op {
	default:
		switch n.Op {
		default:
			var n1 gc.Node
			if !dotaddable(n, &n1) {
				gc.Igen(n, &n1, nil)
				sclean[nsclean-1] = n1
			}

			n = &n1

		case gc.ONAME, gc.OINDREG:
			// nothing
		}

		*lo = *n
		*hi = *n
		lo.Type = gc.Types[gc.TUINT32]
		if n.Type.Etype == gc.TINT64 {
			hi.Type = gc.Types[gc.TINT32]
		} else {
			hi.Type = gc.Types[gc.TUINT32]
		}
		hi.Xoffset += 4

	case gc.OLITERAL:
		var n1 gc.Node
		n.Convconst(&n1, n.Type)
		i := n1.Int64()
		gc.Nodconst(lo, gc.Types[gc.TUINT32], int64(uint32(i)))
		i >>= 32
		if n.Type.Etype == gc.TINT64 {
			gc.Nodconst(hi, gc.Types[gc.TINT32], int64(int32(i)))
		} else {
			gc.Nodconst(hi, gc.Types[gc.TUINT32], int64(uint32(i)))
		}
	}
}

作者:glycerin    项目:zygomy   
/*
 * generate
 *	as n, $c (CMP/CMPU)
 */
func ginscon2(as obj.As, n2 *gc.Node, c int64) {
	var n1 gc.Node

	gc.Nodconst(&n1, gc.Types[gc.TINT64], c)

	switch as {
	default:
		gc.Fatalf("ginscon2")

	case ppc64.ACMP:
		if -ppc64.BIG <= c && c <= ppc64.BIG {
			rawgins(as, n2, &n1)
			return
		}

	case ppc64.ACMPU:
		if 0 <= c && c <= 2*ppc64.BIG {
			rawgins(as, n2, &n1)
			return
		}
	}

	// MOV n1 into register first
	var ntmp gc.Node
	gc.Regalloc(&ntmp, gc.Types[gc.TINT64], nil)

	rawgins(ppc64.AMOVD, &n1, &ntmp)
	rawgins(as, n2, &ntmp)
	gc.Regfree(&ntmp)
}

作者:glycerin    项目:zygomy   
/*
 * generate an addressable node in res, containing the value of n.
 * n is an array index, and might be any size; res width is <= 32-bit.
 * returns Prog* to patch to panic call.
 */
func igenindex(n *gc.Node, res *gc.Node, bounded bool) *obj.Prog {
	if !gc.Is64(n.Type) {
		if n.Addable && (gc.Simtype[n.Etype] == gc.TUINT32 || gc.Simtype[n.Etype] == gc.TINT32) {
			// nothing to do.
			*res = *n
		} else {
			gc.Tempname(res, gc.Types[gc.TUINT32])
			gc.Cgen(n, res)
		}

		return nil
	}

	var tmp gc.Node
	gc.Tempname(&tmp, gc.Types[gc.TINT64])
	gc.Cgen(n, &tmp)
	var lo gc.Node
	var hi gc.Node
	split64(&tmp, &lo, &hi)
	gc.Tempname(res, gc.Types[gc.TUINT32])
	gmove(&lo, res)
	if bounded {
		splitclean()
		return nil
	}

	var zero gc.Node
	gc.Nodconst(&zero, gc.Types[gc.TINT32], 0)
	gins(x86.ACMPL, &hi, &zero)
	splitclean()
	return gc.Gbranch(x86.AJNE, nil, +1)
}

作者:glycerin    项目:zygomy   
/*
 * generate array index into res.
 * n might be any size; res is 32-bit.
 * returns Prog* to patch to panic call.
 */
func cgenindex(n *gc.Node, res *gc.Node, bounded bool) *obj.Prog {
	if !gc.Is64(n.Type) {
		gc.Cgen(n, res)
		return nil
	}

	var tmp gc.Node
	gc.Tempname(&tmp, gc.Types[gc.TINT64])
	gc.Cgen(n, &tmp)
	var lo gc.Node
	var hi gc.Node
	split64(&tmp, &lo, &hi)
	gmove(&lo, res)
	if bounded {
		splitclean()
		return nil
	}

	var n1 gc.Node
	gc.Regalloc(&n1, gc.Types[gc.TINT32], nil)
	var n2 gc.Node
	gc.Regalloc(&n2, gc.Types[gc.TINT32], nil)
	var zero gc.Node
	gc.Nodconst(&zero, gc.Types[gc.TINT32], 0)
	gmove(&hi, &n1)
	gmove(&zero, &n2)
	gins(arm.ACMP, &n1, &n2)
	gc.Regfree(&n2)
	gc.Regfree(&n1)
	splitclean()
	return gc.Gbranch(arm.ABNE, nil, -1)
}

作者:glycerin    项目:zygomy   
func ncon(i uint32) *gc.Node {
	if ncon_n.Type == nil {
		gc.Nodconst(&ncon_n, gc.Types[gc.TUINT32], 0)
	}
	ncon_n.SetInt(int64(i))
	return &ncon_n
}

作者:glycerin    项目:zygomy   
/*
 * generate
 *	as $c, reg
 */
func gconreg(as obj.As, c int64, reg int) {
	var n1 gc.Node
	var n2 gc.Node

	gc.Nodconst(&n1, gc.Types[gc.TINT64], c)
	gc.Nodreg(&n2, gc.Types[gc.TINT64], reg)
	gins(as, &n1, &n2)
}

作者:glycerin    项目:zygomy   
/*
 * generate
 *	as $c, n
 */
func ginscon(as obj.As, c int64, n *gc.Node) {
	var n1 gc.Node
	gc.Nodconst(&n1, gc.Types[gc.TINT32], c)
	var n2 gc.Node
	gc.Regalloc(&n2, gc.Types[gc.TINT32], nil)
	gmove(&n1, &n2)
	gins(as, &n2, n)
	gc.Regfree(&n2)
}

作者:glycerin    项目:zygomy   
func bignodes() {
	if bignodes_did {
		return
	}
	bignodes_did = true

	gc.Nodconst(&zerof, gc.Types[gc.TINT64], 0)
	zerof.Convconst(&zerof, gc.Types[gc.TFLOAT64])

	var i big.Int
	i.SetInt64(1)
	i.Lsh(&i, 63)
	var bigi gc.Node

	gc.Nodconst(&bigi, gc.Types[gc.TUINT64], 0)
	bigi.SetBigInt(&i)
	bigi.Convconst(&two63f, gc.Types[gc.TFLOAT64])

	gc.Nodconst(&bigi, gc.Types[gc.TUINT64], 0)
	i.Lsh(&i, 1)
	bigi.SetBigInt(&i)
	bigi.Convconst(&two64f, gc.Types[gc.TFLOAT64])
}

作者:glycerin    项目:zygomy   
func ginsnop() {
	var con gc.Node
	gc.Nodconst(&con, gc.Types[gc.TINT], 0)
	gins(arm64.AHINT, &con, nil)
}

作者:glycerin    项目:zygomy   
//.........这里部分代码省略.........

			goto olsh_break
		}

		gc.Regalloc(&s, gc.Types[gc.TUINT32], nil)
		gc.Regalloc(&creg, gc.Types[gc.TUINT32], nil)
		if gc.Is64(r.Type) {
			// shift is >= 1<<32
			var cl gc.Node
			var ch gc.Node
			split64(r, &cl, &ch)

			gmove(&ch, &s)
			gins(arm.ATST, &s, nil)
			p6 = gc.Gbranch(arm.ABNE, nil, 0)
			gmove(&cl, &s)
			splitclean()
		} else {
			gmove(r, &s)
			p6 = nil
		}

		gins(arm.ATST, &s, nil)

		// shift == 0
		p1 = gins(arm.AMOVW, &bl, &al)

		p1.Scond = arm.C_SCOND_EQ
		p1 = gins(arm.AMOVW, &bh, &ah)
		p1.Scond = arm.C_SCOND_EQ
		p2 = gc.Gbranch(arm.ABEQ, nil, 0)

		// shift is < 32
		gc.Nodconst(&n1, gc.Types[gc.TUINT32], 32)

		gmove(&n1, &creg)
		gins(arm.ACMP, &s, &creg)

		//	MOVW.LO		bl<<s, al
		p1 = gregshift(arm.AMOVW, &bl, arm.SHIFT_LL, &s, &al)

		p1.Scond = arm.C_SCOND_LO

		//	MOVW.LO		bh<<s, ah
		p1 = gregshift(arm.AMOVW, &bh, arm.SHIFT_LL, &s, &ah)

		p1.Scond = arm.C_SCOND_LO

		//	SUB.LO		s, creg
		p1 = gins(arm.ASUB, &s, &creg)

		p1.Scond = arm.C_SCOND_LO

		//	OR.LO		bl>>creg, ah
		p1 = gregshift(arm.AORR, &bl, arm.SHIFT_LR, &creg, &ah)

		p1.Scond = arm.C_SCOND_LO

		//	BLO	end
		p3 = gc.Gbranch(arm.ABLO, nil, 0)

		// shift == 32
		p1 = gins(arm.AEOR, &al, &al)

		p1.Scond = arm.C_SCOND_EQ
		p1 = gins(arm.AMOVW, &bl, &ah)

作者:glycerin    项目:zygomy   
func clearfat_tail(n1 *gc.Node, b int64) {
	if b >= 16 && isPlan9 {
		var z gc.Node
		gc.Nodconst(&z, gc.Types[gc.TUINT64], 0)
		q := b / 8
		for ; q > 0; q-- {
			n1.Type = z.Type
			gins(x86.AMOVQ, &z, n1)
			n1.Xoffset += 8
			b -= 8
		}
		if b != 0 {
			n1.Xoffset -= 8 - b
			gins(x86.AMOVQ, &z, n1)
		}
		return
	}
	if b >= 16 {
		var vec_zero gc.Node
		gc.Regalloc(&vec_zero, gc.Types[gc.TFLOAT64], nil)
		gins(x86.AXORPS, &vec_zero, &vec_zero)

		for b >= 16 {
			gins(x86.AMOVUPS, &vec_zero, n1)
			n1.Xoffset += 16
			b -= 16
		}

		// MOVUPS X0, off(base) is a few bytes shorter than MOV 0, off(base)
		if b != 0 {
			n1.Xoffset -= 16 - b
			gins(x86.AMOVUPS, &vec_zero, n1)
		}

		gc.Regfree(&vec_zero)
		return
	}

	// Write sequence of MOV 0, off(base) instead of using STOSQ.
	// The hope is that although the code will be slightly longer,
	// the MOVs will have no dependencies and pipeline better
	// than the unrolled STOSQ loop.
	var z gc.Node
	gc.Nodconst(&z, gc.Types[gc.TUINT64], 0)
	if b >= 8 {
		n1.Type = z.Type
		gins(x86.AMOVQ, &z, n1)
		n1.Xoffset += 8
		b -= 8

		if b != 0 {
			n1.Xoffset -= 8 - b
			gins(x86.AMOVQ, &z, n1)
		}
		return
	}

	if b >= 4 {
		gc.Nodconst(&z, gc.Types[gc.TUINT32], 0)
		n1.Type = z.Type
		gins(x86.AMOVL, &z, n1)
		n1.Xoffset += 4
		b -= 4

		if b != 0 {
			n1.Xoffset -= 4 - b
			gins(x86.AMOVL, &z, n1)
		}
		return
	}

	if b >= 2 {
		gc.Nodconst(&z, gc.Types[gc.TUINT16], 0)
		n1.Type = z.Type
		gins(x86.AMOVW, &z, n1)
		n1.Xoffset += 2
		b -= 2
	}

	gc.Nodconst(&z, gc.Types[gc.TUINT8], 0)
	for b > 0 {
		n1.Type = z.Type
		gins(x86.AMOVB, &z, n1)
		n1.Xoffset++
		b--
	}

}

作者:glycerin    项目:zygomy   
//.........这里部分代码省略.........
		goto rdst

		// convert via int32
	case gc.TINT16<<16 | gc.TFLOAT32,
		gc.TINT16<<16 | gc.TFLOAT64,
		gc.TINT8<<16 | gc.TFLOAT32,
		gc.TINT8<<16 | gc.TFLOAT64,
		gc.TUINT16<<16 | gc.TFLOAT32,
		gc.TUINT16<<16 | gc.TFLOAT64,
		gc.TUINT8<<16 | gc.TFLOAT32,
		gc.TUINT8<<16 | gc.TFLOAT64:
		cvt = gc.Types[gc.TINT32]

		goto hard

		// convert via int64.
	case gc.TUINT32<<16 | gc.TFLOAT32,
		gc.TUINT32<<16 | gc.TFLOAT64:
		cvt = gc.Types[gc.TINT64]

		goto hard

		// algorithm is:
	//	if small enough, use native int64 -> uint64 conversion.
	//	otherwise, halve (rounding to odd?), convert, and double.
	case gc.TUINT64<<16 | gc.TFLOAT32,
		gc.TUINT64<<16 | gc.TFLOAT64:
		a := x86.ACVTSQ2SS

		if tt == gc.TFLOAT64 {
			a = x86.ACVTSQ2SD
		}
		var zero gc.Node
		gc.Nodconst(&zero, gc.Types[gc.TUINT64], 0)
		var one gc.Node
		gc.Nodconst(&one, gc.Types[gc.TUINT64], 1)
		var r1 gc.Node
		gc.Regalloc(&r1, f.Type, f)
		var r2 gc.Node
		gc.Regalloc(&r2, t.Type, t)
		var r3 gc.Node
		gc.Regalloc(&r3, f.Type, nil)
		var r4 gc.Node
		gc.Regalloc(&r4, f.Type, nil)
		gmove(f, &r1)
		gins(x86.ACMPQ, &r1, &zero)
		p1 := gc.Gbranch(x86.AJLT, nil, +1)
		gins(a, &r1, &r2)
		p2 := gc.Gbranch(obj.AJMP, nil, 0)
		gc.Patch(p1, gc.Pc)
		gmove(&r1, &r3)
		gins(x86.ASHRQ, &one, &r3)
		gmove(&r1, &r4)
		gins(x86.AANDL, &one, &r4)
		gins(x86.AORQ, &r4, &r3)
		gins(a, &r3, &r2)
		gins(optoas(gc.OADD, t.Type), &r2, &r2)
		gc.Patch(p2, gc.Pc)
		gmove(&r2, t)
		gc.Regfree(&r4)
		gc.Regfree(&r3)
		gc.Regfree(&r2)
		gc.Regfree(&r1)
		return

		/*

作者:glycerin    项目:zygomy   
func clearfat(nl *gc.Node) {
	/* clear a fat object */
	if gc.Debug['g'] != 0 {
		gc.Dump("\nclearfat", nl)
	}

	w := uint32(nl.Type.Width)

	// Avoid taking the address for simple enough types.
	if gc.Componentgen(nil, nl) {
		return
	}

	c := w % 4 // bytes
	q := w / 4 // quads

	if nl.Type.Align < 4 {
		q = 0
		c = w
	}

	var r0 gc.Node
	r0.Op = gc.OREGISTER

	r0.Reg = arm.REG_R0
	var r1 gc.Node
	r1.Op = gc.OREGISTER
	r1.Reg = arm.REG_R1
	var dst gc.Node
	gc.Regalloc(&dst, gc.Types[gc.Tptr], &r1)
	gc.Agen(nl, &dst)
	var nc gc.Node
	gc.Nodconst(&nc, gc.Types[gc.TUINT32], 0)
	var nz gc.Node
	gc.Regalloc(&nz, gc.Types[gc.TUINT32], &r0)
	gc.Cgen(&nc, &nz)

	if q > 128 {
		var end gc.Node
		gc.Regalloc(&end, gc.Types[gc.Tptr], nil)
		p := gins(arm.AMOVW, &dst, &end)
		p.From.Type = obj.TYPE_ADDR
		p.From.Offset = int64(q) * 4

		p = gins(arm.AMOVW, &nz, &dst)
		p.To.Type = obj.TYPE_MEM
		p.To.Offset = 4
		p.Scond |= arm.C_PBIT
		pl := p

		p = gins(arm.ACMP, &dst, nil)
		raddr(&end, p)
		gc.Patch(gc.Gbranch(arm.ABNE, nil, 0), pl)

		gc.Regfree(&end)
	} else if q >= 4 && !gc.Nacl {
		f := gc.Sysfunc("duffzero")
		p := gins(obj.ADUFFZERO, nil, f)
		gc.Afunclit(&p.To, f)

		// 4 and 128 = magic constants: see ../../runtime/asm_arm.s
		p.To.Offset = 4 * (128 - int64(q))
	} else {
		var p *obj.Prog
		for q > 0 {
			p = gins(arm.AMOVW, &nz, &dst)
			p.To.Type = obj.TYPE_MEM
			p.To.Offset = 4
			p.Scond |= arm.C_PBIT

			//print("1. %v\n", p);
			q--
		}
	}

	if c > 4 {
		// Loop to zero unaligned memory.
		var end gc.Node
		gc.Regalloc(&end, gc.Types[gc.Tptr], nil)
		p := gins(arm.AMOVW, &dst, &end)
		p.From.Type = obj.TYPE_ADDR
		p.From.Offset = int64(c)

		p = gins(arm.AMOVB, &nz, &dst)
		p.To.Type = obj.TYPE_MEM
		p.To.Offset = 1
		p.Scond |= arm.C_PBIT
		pl := p

		p = gins(arm.ACMP, &dst, nil)
		raddr(&end, p)
		gc.Patch(gc.Gbranch(arm.ABNE, nil, 0), pl)

		gc.Regfree(&end)
		c = 0
	}
	var p *obj.Prog
	for c > 0 {
		p = gins(arm.AMOVB, &nz, &dst)
		p.To.Type = obj.TYPE_MEM
//.........这里部分代码省略.........

作者:glycerin    项目:zygomy   
/*
 * generate division.
 * generates one of:
 *	res = nl / nr
 *	res = nl % nr
 * according to op.
 */
func dodiv(op gc.Op, nl *gc.Node, nr *gc.Node, res *gc.Node) {
	// Have to be careful about handling
	// most negative int divided by -1 correctly.
	// The hardware will trap.
	// Also the byte divide instruction needs AH,
	// which we otherwise don't have to deal with.
	// Easiest way to avoid for int8, int16: use int32.
	// For int32 and int64, use explicit test.
	// Could use int64 hw for int32.
	t := nl.Type

	t0 := t
	check := false
	if t.IsSigned() {
		check = true
		if gc.Isconst(nl, gc.CTINT) && nl.Int64() != -(1<<uint64(t.Width*8-1)) {
			check = false
		} else if gc.Isconst(nr, gc.CTINT) && nr.Int64() != -1 {
			check = false
		}
	}

	if t.Width < 4 {
		if t.IsSigned() {
			t = gc.Types[gc.TINT32]
		} else {
			t = gc.Types[gc.TUINT32]
		}
		check = false
	}

	a := optoas(op, t)

	var n3 gc.Node
	gc.Regalloc(&n3, t0, nil)
	var ax gc.Node
	var oldax gc.Node
	if nl.Ullman >= nr.Ullman {
		savex(x86.REG_AX, &ax, &oldax, res, t0)
		gc.Cgen(nl, &ax)
		gc.Regalloc(&ax, t0, &ax) // mark ax live during cgen
		gc.Cgen(nr, &n3)
		gc.Regfree(&ax)
	} else {
		gc.Cgen(nr, &n3)
		savex(x86.REG_AX, &ax, &oldax, res, t0)
		gc.Cgen(nl, &ax)
	}

	if t != t0 {
		// Convert
		ax1 := ax

		n31 := n3
		ax.Type = t
		n3.Type = t
		gmove(&ax1, &ax)
		gmove(&n31, &n3)
	}

	var n4 gc.Node
	if gc.Nacl {
		// Native Client does not relay the divide-by-zero trap
		// to the executing program, so we must insert a check
		// for ourselves.
		gc.Nodconst(&n4, t, 0)

		gins(optoas(gc.OCMP, t), &n3, &n4)
		p1 := gc.Gbranch(optoas(gc.ONE, t), nil, +1)
		if panicdiv == nil {
			panicdiv = gc.Sysfunc("panicdivide")
		}
		gc.Ginscall(panicdiv, -1)
		gc.Patch(p1, gc.Pc)
	}

	var p2 *obj.Prog
	if check {
		gc.Nodconst(&n4, t, -1)
		gins(optoas(gc.OCMP, t), &n3, &n4)
		p1 := gc.Gbranch(optoas(gc.ONE, t), nil, +1)
		if op == gc.ODIV {
			// a / (-1) is -a.
			gins(optoas(gc.OMINUS, t), nil, &ax)

			gmove(&ax, res)
		} else {
			// a % (-1) is 0.
			gc.Nodconst(&n4, t, 0)

			gmove(&n4, res)
		}

//.........这里部分代码省略.........

作者:glycerin    项目:zygomy   
/*
 * generate shift according to op, one of:
 *	res = nl << nr
 *	res = nl >> nr
 */
func cgen_shift(op gc.Op, bounded bool, nl *gc.Node, nr *gc.Node, res *gc.Node) {
	if nl.Type.Width > 4 {
		gc.Fatalf("cgen_shift %v", nl.Type)
	}

	w := int(nl.Type.Width * 8)

	if op == gc.OLROT {
		v := nr.Int64()
		var n1 gc.Node
		gc.Regalloc(&n1, nl.Type, res)
		if w == 32 {
			gc.Cgen(nl, &n1)
			gshift(arm.AMOVW, &n1, arm.SHIFT_RR, int32(w)-int32(v), &n1)
		} else {
			var n2 gc.Node
			gc.Regalloc(&n2, nl.Type, nil)
			gc.Cgen(nl, &n2)
			gshift(arm.AMOVW, &n2, arm.SHIFT_LL, int32(v), &n1)
			gshift(arm.AORR, &n2, arm.SHIFT_LR, int32(w)-int32(v), &n1)
			gc.Regfree(&n2)

			// Ensure sign/zero-extended result.
			gins(optoas(gc.OAS, nl.Type), &n1, &n1)
		}

		gmove(&n1, res)
		gc.Regfree(&n1)
		return
	}

	if nr.Op == gc.OLITERAL {
		var n1 gc.Node
		gc.Regalloc(&n1, nl.Type, res)
		gc.Cgen(nl, &n1)
		sc := uint64(nr.Int64())
		if sc == 0 {
		} else // nothing to do
		if sc >= uint64(nl.Type.Width*8) {
			if op == gc.ORSH && nl.Type.IsSigned() {
				gshift(arm.AMOVW, &n1, arm.SHIFT_AR, int32(w), &n1)
			} else {
				gins(arm.AEOR, &n1, &n1)
			}
		} else {
			if op == gc.ORSH && nl.Type.IsSigned() {
				gshift(arm.AMOVW, &n1, arm.SHIFT_AR, int32(sc), &n1)
			} else if op == gc.ORSH {
				gshift(arm.AMOVW, &n1, arm.SHIFT_LR, int32(sc), &n1) // OLSH
			} else {
				gshift(arm.AMOVW, &n1, arm.SHIFT_LL, int32(sc), &n1)
			}
		}

		if w < 32 && op == gc.OLSH {
			gins(optoas(gc.OAS, nl.Type), &n1, &n1)
		}
		gmove(&n1, res)
		gc.Regfree(&n1)
		return
	}

	tr := nr.Type
	var t gc.Node
	var n1 gc.Node
	var n2 gc.Node
	var n3 gc.Node
	if tr.Width > 4 {
		var nt gc.Node
		gc.Tempname(&nt, nr.Type)
		if nl.Ullman >= nr.Ullman {
			gc.Regalloc(&n2, nl.Type, res)
			gc.Cgen(nl, &n2)
			gc.Cgen(nr, &nt)
			n1 = nt
		} else {
			gc.Cgen(nr, &nt)
			gc.Regalloc(&n2, nl.Type, res)
			gc.Cgen(nl, &n2)
		}

		var hi gc.Node
		var lo gc.Node
		split64(&nt, &lo, &hi)
		gc.Regalloc(&n1, gc.Types[gc.TUINT32], nil)
		gc.Regalloc(&n3, gc.Types[gc.TUINT32], nil)
		gmove(&lo, &n1)
		gmove(&hi, &n3)
		splitclean()
		gins(arm.ATST, &n3, nil)
		gc.Nodconst(&t, gc.Types[gc.TUINT32], int64(w))
		p1 := gins(arm.AMOVW, &t, &n1)
		p1.Scond = arm.C_SCOND_NE
		tr = gc.Types[gc.TUINT32]
		gc.Regfree(&n3)
//.........这里部分代码省略.........


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