コード例 #1
0
ファイル: gsubr.go プロジェクト: bibbyflyaway/go
/*
 * generate
 *	as $c, n
 */
func ginscon(as int, 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)
}
コード例 #2
0
ファイル: gsubr.go プロジェクト: xslonepiece/goios
/*
 * 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.Fatal("split64 %v", gc.Tconv(n.Type, 0))
	}

	if nsclean >= len(sclean) {
		gc.Fatal("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:
			if n.Class == gc.PPARAMREF {
				var n1 gc.Node
				gc.Cgen(n.Heapaddr, &n1)
				sclean[nsclean-1] = n1
				n = &n1
			}

			// nothing
		case gc.OINDREG:
			break
		}

		*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
		gc.Convconst(&n1, n.Type, &n.Val)
		i := gc.Mpgetfix(n1.Val.U.Xval)
		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)))
		}
	}
}
コード例 #3
0
ファイル: cgen.go プロジェクト: tidatida/go
/*
 * 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 != 0 {
			// 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)
}
コード例 #4
0
ファイル: gsubr.go プロジェクト: bibbyflyaway/go
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
}
コード例 #5
0
ファイル: cgen.go プロジェクト: bibbyflyaway/go
/*
 * 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)
}
コード例 #6
0
ファイル: gsubr.go プロジェクト: xslonepiece/goios
func ncon(i uint32) *gc.Node {
	if ncon_n.Type == nil {
		gc.Nodconst(&ncon_n, gc.Types[gc.TUINT32], 0)
	}
	gc.Mpmovecfix(ncon_n.Val.U.Xval, int64(i))
	return &ncon_n
}
コード例 #7
0
ファイル: gsubr.go プロジェクト: tidatida/go
/*
 * generate
 *	as n, $c (CMP/CMPU)
 */
func ginscon2(as int, n2 *gc.Node, c int64) {
	var n1 gc.Node

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

	switch as {
	default:
		gc.Fatal("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)
}
コード例 #8
0
ファイル: gsubr.go プロジェクト: xslonepiece/goios
/*
 * generate
 *	as $c, reg
 */
func gconreg(as int, 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)
}
コード例 #9
0
ファイル: ggen.go プロジェクト: bibbyflyaway/go
/*
 * generate
 *	as $c, n
 */
func ginscon(as int, 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)
}
コード例 #10
0
ファイル: gsubr.go プロジェクト: bibbyflyaway/go
func bignodes() {
	if bignodes_did {
		return
	}
	bignodes_did = true

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

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

	bigi.Convconst(&bigf, gc.Types[gc.TFLOAT64])
}
コード例 #11
0
ファイル: gsubr.go プロジェクト: tidatida/go
func bignodes() {
	if bignodes_did != 0 {
		return
	}
	bignodes_did = 1

	gc.Nodconst(&bigi, gc.Types[gc.TUINT64], 1)
	gc.Mpshiftfix(bigi.Val.U.Xval, 63)

	bigf = bigi
	bigf.Type = gc.Types[gc.TFLOAT64]
	bigf.Val.Ctype = gc.CTFLT
	bigf.Val.U.Fval = new(gc.Mpflt)
	gc.Mpmovefixflt(bigf.Val.U.Fval, bigi.Val.U.Xval)
}
コード例 #12
0
ファイル: gsubr.go プロジェクト: tidatida/go
/*
 * generate
 *	as $c, n
 */
func ginscon(as int, c int64, n2 *gc.Node) {
	var n1 gc.Node

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

	if as != ppc64.AMOVD && (c < -ppc64.BIG || c > ppc64.BIG) || n2.Op != gc.OREGISTER || as == ppc64.AMULLD {
		// cannot have more than 16-bit of immediate in ADD, etc.
		// instead, MOV into register first.
		var ntmp gc.Node
		gc.Regalloc(&ntmp, gc.Types[gc.TINT64], nil)

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

	rawgins(as, &n1, n2)
}
コード例 #13
0
ファイル: cgen.go プロジェクト: xslonepiece/goios
func gencmp0(n *gc.Node, t *gc.Type, o int, likely int, to *obj.Prog) {
	var n1 gc.Node

	gc.Regalloc(&n1, t, nil)
	gc.Cgen(n, &n1)
	a := optoas(gc.OCMP, t)
	if a != arm.ACMP {
		var n2 gc.Node
		gc.Nodconst(&n2, t, 0)
		var n3 gc.Node
		gc.Regalloc(&n3, t, nil)
		gmove(&n2, &n3)
		gins(a, &n1, &n3)
		gc.Regfree(&n3)
	} else {
		gins(arm.ATST, &n1, nil)
	}
	a = optoas(o, t)
	gc.Patch(gc.Gbranch(a, t, likely), to)
	gc.Regfree(&n1)
}
コード例 #14
0
ファイル: ggen.go プロジェクト: klueska/go-akaros
/*
 * generate shift according to op, one of:
 *	res = nl << nr
 *	res = nl >> nr
 */
func cgen_shift(op int, bounded bool, nl *gc.Node, nr *gc.Node, res *gc.Node) {
	a := int(optoas(op, nl.Type))

	if nr.Op == gc.OLITERAL {
		var n1 gc.Node
		regalloc(&n1, nl.Type, res)
		cgen(nl, &n1)
		sc := uint64(uint64(gc.Mpgetfix(nr.Val.U.Xval)))
		if sc >= uint64(nl.Type.Width*8) {
			// large shift gets 2 shifts by width-1
			var n3 gc.Node
			gc.Nodconst(&n3, gc.Types[gc.TUINT32], nl.Type.Width*8-1)

			gins(a, &n3, &n1)
			gins(a, &n3, &n1)
		} else {
			gins(a, nr, &n1)
		}
		gmove(&n1, res)
		regfree(&n1)
		return
	}

	if nl.Ullman >= gc.UINF {
		var n4 gc.Node
		gc.Tempname(&n4, nl.Type)
		cgen(nl, &n4)
		nl = &n4
	}

	if nr.Ullman >= gc.UINF {
		var n5 gc.Node
		gc.Tempname(&n5, nr.Type)
		cgen(nr, &n5)
		nr = &n5
	}

	// Allow either uint32 or uint64 as shift type,
	// to avoid unnecessary conversion from uint32 to uint64
	// just to do the comparison.
	tcount := gc.Types[gc.Simtype[nr.Type.Etype]]

	if tcount.Etype < gc.TUINT32 {
		tcount = gc.Types[gc.TUINT32]
	}

	var n1 gc.Node
	regalloc(&n1, nr.Type, nil) // to hold the shift type in CX
	var n3 gc.Node
	regalloc(&n3, tcount, &n1) // to clear high bits of CX

	var n2 gc.Node
	regalloc(&n2, nl.Type, res)

	if nl.Ullman >= nr.Ullman {
		cgen(nl, &n2)
		cgen(nr, &n1)
		gmove(&n1, &n3)
	} else {
		cgen(nr, &n1)
		gmove(&n1, &n3)
		cgen(nl, &n2)
	}

	regfree(&n3)

	// test and fix up large shifts
	if !bounded {
		gc.Nodconst(&n3, tcount, nl.Type.Width*8)
		gins(optoas(gc.OCMP, tcount), &n1, &n3)
		p1 := (*obj.Prog)(gc.Gbranch(optoas(gc.OLT, tcount), nil, +1))
		if op == gc.ORSH && gc.Issigned[nl.Type.Etype] {
			gc.Nodconst(&n3, gc.Types[gc.TUINT32], nl.Type.Width*8-1)
			gins(a, &n3, &n2)
		} else {
			gc.Nodconst(&n3, nl.Type, 0)
			gmove(&n3, &n2)
		}

		gc.Patch(p1, gc.Pc)
	}

	gins(a, &n1, &n2)

	gmove(&n2, res)

	regfree(&n1)
	regfree(&n2)
}
コード例 #15
0
ファイル: gsubr.go プロジェクト: klueska/go-akaros
func anyregalloc() bool {
	var j int

	for i := int(0); i < len(reg); i++ {
		if reg[i] == 0 {
			goto ok
		}
		for j = 0; j < len(resvd); j++ {
			if resvd[j] == i {
				goto ok
			}
		}
		return true
	ok:
	}

	return false
}

/*
 * allocate register of type t, leave in n.
 * if o != N, o is desired fixed register.
 * caller must regfree(n).
 */
func regalloc(n *gc.Node, t *gc.Type, o *gc.Node) {
	if t == nil {
		gc.Fatal("regalloc: t nil")
	}
	et := int(int(gc.Simtype[t.Etype]))

	if gc.Debug['r'] != 0 {
		fixfree := int(0)
		fltfree := int(0)
		for i := int(arm64.REG_R0); i < arm64.REG_F31; i++ {
			if reg[i-arm64.REG_R0] == 0 {
				if i < arm64.REG_F0 {
					fixfree++
				} else {
					fltfree++
				}
			}
		}

		fmt.Printf("regalloc fix %d flt %d free\n", fixfree, fltfree)
	}

	var i int
	switch et {
	case gc.TINT8,
		gc.TUINT8,
		gc.TINT16,
		gc.TUINT16,
		gc.TINT32,
		gc.TUINT32,
		gc.TINT64,
		gc.TUINT64,
		gc.TPTR32,
		gc.TPTR64,
		gc.TBOOL:
		if o != nil && o.Op == gc.OREGISTER {
			i = int(o.Val.U.Reg)
			if i >= arm64.REGMIN && i <= arm64.REGMAX {
				goto out
			}
		}

		for i = arm64.REGMIN; i <= arm64.REGMAX; i++ {
			if reg[i-arm64.REG_R0] == 0 {
				regpc[i-arm64.REG_R0] = uint32(obj.Getcallerpc(&n))
				goto out
			}
		}

		gc.Flusherrors()
		for i := int(arm64.REG_R0); i < arm64.REG_R0+arm64.NREG; i++ {
			fmt.Printf("R%d %p\n", i, regpc[i-arm64.REG_R0])
		}
		gc.Fatal("out of fixed registers")

	case gc.TFLOAT32,
		gc.TFLOAT64:
		if o != nil && o.Op == gc.OREGISTER {
			i = int(o.Val.U.Reg)
			if i >= arm64.FREGMIN && i <= arm64.FREGMAX {
				goto out
			}
		}

		for i = arm64.FREGMIN; i <= arm64.FREGMAX; i++ {
			if reg[i-arm64.REG_R0] == 0 {
				regpc[i-arm64.REG_R0] = uint32(obj.Getcallerpc(&n))
				goto out
			}
		}

		gc.Flusherrors()
		for i := int(arm64.REG_F0); i < arm64.REG_F0+arm64.NREG; i++ {
			fmt.Printf("F%d %p\n", i, regpc[i-arm64.REG_R0])
		}
		gc.Fatal("out of floating registers")

	case gc.TCOMPLEX64,
		gc.TCOMPLEX128:
		gc.Tempname(n, t)
		return
	}

	gc.Fatal("regalloc: unknown type %v", gc.Tconv(t, 0))
	return

out:
	reg[i-arm64.REG_R0]++
	gc.Nodreg(n, t, i)
}

func regfree(n *gc.Node) {
	if n.Op == gc.ONAME {
		return
	}
	if n.Op != gc.OREGISTER && n.Op != gc.OINDREG {
		gc.Fatal("regfree: not a register")
	}
	i := int(int(n.Val.U.Reg) - arm64.REG_R0)
	if i == arm64.REGSP-arm64.REG_R0 {
		return
	}
	if i < 0 || i >= len(reg) {
		gc.Fatal("regfree: reg out of range")
	}
	if reg[i] <= 0 {
		gc.Fatal("regfree: reg not allocated")
	}
	reg[i]--
	if reg[i] == 0 {
		regpc[i] = 0
	}
}

/*
 * generate
 *	as $c, n
 */
func ginscon(as int, c int64, n2 *gc.Node) {
	var n1 gc.Node

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

	if as != arm64.AMOVD && (c < -arm64.BIG || c > arm64.BIG) {
		// cannot have more than 16-bit of immediate in ADD, etc.
		// instead, MOV into register first.
		var ntmp gc.Node
		regalloc(&ntmp, gc.Types[gc.TINT64], nil)

		gins(arm64.AMOVD, &n1, &ntmp)
		gins(as, &ntmp, n2)
		regfree(&ntmp)
		return
	}

	gins(as, &n1, n2)
}

/*
 * generate
 *	as n, $c (CMP)
 */
func ginscon2(as int, n2 *gc.Node, c int64) {
	var n1 gc.Node

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

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

	case arm64.ACMP:
		if -arm64.BIG <= c && c <= arm64.BIG {
			gcmp(as, n2, &n1)
			return
		}
	}

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

	gins(arm64.AMOVD, &n1, &ntmp)
	gcmp(as, n2, &ntmp)
	regfree(&ntmp)
}

/*
 * generate move:
 *	t = f
 * hard part is conversions.
 */
func gmove(f *gc.Node, t *gc.Node) {
	if gc.Debug['M'] != 0 {
		fmt.Printf("gmove %v -> %v\n", gc.Nconv(f, obj.FmtLong), gc.Nconv(t, obj.FmtLong))
	}

	ft := int(gc.Simsimtype(f.Type))
	tt := int(gc.Simsimtype(t.Type))
	cvt := (*gc.Type)(t.Type)

	if gc.Iscomplex[ft] || gc.Iscomplex[tt] {
		gc.Complexmove(f, t)
		return
	}

	// cannot have two memory operands
	var r1 gc.Node
	var a int
	if gc.Ismem(f) && gc.Ismem(t) {
		goto hard
	}

	// convert constant to desired type
	if f.Op == gc.OLITERAL {
		var con gc.Node
		switch tt {
		default:
			gc.Convconst(&con, t.Type, &f.Val)

		case gc.TINT32,
			gc.TINT16,
			gc.TINT8:
			var con gc.Node
			gc.Convconst(&con, gc.Types[gc.TINT64], &f.Val)
			var r1 gc.Node
			regalloc(&r1, con.Type, t)
			gins(arm64.AMOVD, &con, &r1)
			gmove(&r1, t)
			regfree(&r1)
			return

		case gc.TUINT32,
			gc.TUINT16,
			gc.TUINT8:
			var con gc.Node
			gc.Convconst(&con, gc.Types[gc.TUINT64], &f.Val)
			var r1 gc.Node
			regalloc(&r1, con.Type, t)
			gins(arm64.AMOVD, &con, &r1)
			gmove(&r1, t)
			regfree(&r1)
			return
		}

		f = &con
		ft = tt // so big switch will choose a simple mov

		// constants can't move directly to memory.
		if gc.Ismem(t) {
			goto hard
		}
	}

	// value -> value copy, first operand in memory.
	// any floating point operand requires register
	// src, so goto hard to copy to register first.
	if gc.Ismem(f) && ft != tt && (gc.Isfloat[ft] || gc.Isfloat[tt]) {
		cvt = gc.Types[ft]
		goto hard
	}

	// value -> value copy, only one memory operand.
	// figure out the instruction to use.
	// break out of switch for one-instruction gins.
	// goto rdst for "destination must be register".
	// goto hard for "convert to cvt type first".
	// otherwise handle and return.

	switch uint32(ft)<<16 | uint32(tt) {
	default:
		gc.Fatal("gmove %v -> %v", gc.Tconv(f.Type, obj.FmtLong), gc.Tconv(t.Type, obj.FmtLong))

		/*
		 * integer copy and truncate
		 */
	case gc.TINT8<<16 | gc.TINT8, // same size
		gc.TUINT8<<16 | gc.TINT8,
		gc.TINT16<<16 | gc.TINT8,
		// truncate
		gc.TUINT16<<16 | gc.TINT8,
		gc.TINT32<<16 | gc.TINT8,
		gc.TUINT32<<16 | gc.TINT8,
		gc.TINT64<<16 | gc.TINT8,
		gc.TUINT64<<16 | gc.TINT8:
		a = arm64.AMOVB

	case gc.TINT8<<16 | gc.TUINT8, // same size
		gc.TUINT8<<16 | gc.TUINT8,
		gc.TINT16<<16 | gc.TUINT8,
		// truncate
		gc.TUINT16<<16 | gc.TUINT8,
		gc.TINT32<<16 | gc.TUINT8,
		gc.TUINT32<<16 | gc.TUINT8,
		gc.TINT64<<16 | gc.TUINT8,
		gc.TUINT64<<16 | gc.TUINT8:
		a = arm64.AMOVBU

	case gc.TINT16<<16 | gc.TINT16, // same size
		gc.TUINT16<<16 | gc.TINT16,
		gc.TINT32<<16 | gc.TINT16,
		// truncate
		gc.TUINT32<<16 | gc.TINT16,
		gc.TINT64<<16 | gc.TINT16,
		gc.TUINT64<<16 | gc.TINT16:
		a = arm64.AMOVH

	case gc.TINT16<<16 | gc.TUINT16, // same size
		gc.TUINT16<<16 | gc.TUINT16,
		gc.TINT32<<16 | gc.TUINT16,
		// truncate
		gc.TUINT32<<16 | gc.TUINT16,
		gc.TINT64<<16 | gc.TUINT16,
		gc.TUINT64<<16 | gc.TUINT16:
		a = arm64.AMOVHU

	case gc.TINT32<<16 | gc.TINT32, // same size
		gc.TUINT32<<16 | gc.TINT32,
		gc.TINT64<<16 | gc.TINT32,
		// truncate
		gc.TUINT64<<16 | gc.TINT32:
		a = arm64.AMOVW

	case gc.TINT32<<16 | gc.TUINT32, // same size
		gc.TUINT32<<16 | gc.TUINT32,
		gc.TINT64<<16 | gc.TUINT32,
		gc.TUINT64<<16 | gc.TUINT32:
		a = arm64.AMOVWU

	case gc.TINT64<<16 | gc.TINT64, // same size
		gc.TINT64<<16 | gc.TUINT64,
		gc.TUINT64<<16 | gc.TINT64,
		gc.TUINT64<<16 | gc.TUINT64:
		a = arm64.AMOVD

		/*
		 * integer up-conversions
		 */
	case gc.TINT8<<16 | gc.TINT16, // sign extend int8
		gc.TINT8<<16 | gc.TUINT16,
		gc.TINT8<<16 | gc.TINT32,
		gc.TINT8<<16 | gc.TUINT32,
		gc.TINT8<<16 | gc.TINT64,
		gc.TINT8<<16 | gc.TUINT64:
		a = arm64.AMOVB

		goto rdst

	case gc.TUINT8<<16 | gc.TINT16, // zero extend uint8
		gc.TUINT8<<16 | gc.TUINT16,
		gc.TUINT8<<16 | gc.TINT32,
		gc.TUINT8<<16 | gc.TUINT32,
		gc.TUINT8<<16 | gc.TINT64,
		gc.TUINT8<<16 | gc.TUINT64:
		a = arm64.AMOVBU

		goto rdst

	case gc.TINT16<<16 | gc.TINT32, // sign extend int16
		gc.TINT16<<16 | gc.TUINT32,
		gc.TINT16<<16 | gc.TINT64,
		gc.TINT16<<16 | gc.TUINT64:
		a = arm64.AMOVH

		goto rdst

	case gc.TUINT16<<16 | gc.TINT32, // zero extend uint16
		gc.TUINT16<<16 | gc.TUINT32,
		gc.TUINT16<<16 | gc.TINT64,
		gc.TUINT16<<16 | gc.TUINT64:
		a = arm64.AMOVHU

		goto rdst

	case gc.TINT32<<16 | gc.TINT64, // sign extend int32
		gc.TINT32<<16 | gc.TUINT64:
		a = arm64.AMOVW

		goto rdst

	case gc.TUINT32<<16 | gc.TINT64, // zero extend uint32
		gc.TUINT32<<16 | gc.TUINT64:
		a = arm64.AMOVWU

		goto rdst

	/*
	* float to integer
	 */
	case gc.TFLOAT32<<16 | gc.TINT32:
		a = arm64.AFCVTZSSW
		goto rdst

	case gc.TFLOAT64<<16 | gc.TINT32:
		a = arm64.AFCVTZSDW
		goto rdst

	case gc.TFLOAT32<<16 | gc.TINT64:
		a = arm64.AFCVTZSS
		goto rdst

	case gc.TFLOAT64<<16 | gc.TINT64:
		a = arm64.AFCVTZSD
		goto rdst

	case gc.TFLOAT32<<16 | gc.TUINT32:
		a = arm64.AFCVTZUSW
		goto rdst

	case gc.TFLOAT64<<16 | gc.TUINT32:
		a = arm64.AFCVTZUDW
		goto rdst

	case gc.TFLOAT32<<16 | gc.TUINT64:
		a = arm64.AFCVTZUS
		goto rdst

	case gc.TFLOAT64<<16 | gc.TUINT64:
		a = arm64.AFCVTZUD
		goto rdst

	case gc.TFLOAT32<<16 | gc.TINT16,
		gc.TFLOAT32<<16 | gc.TINT8,
		gc.TFLOAT64<<16 | gc.TINT16,
		gc.TFLOAT64<<16 | gc.TINT8:
		cvt = gc.Types[gc.TINT32]

		goto hard

	case gc.TFLOAT32<<16 | gc.TUINT16,
		gc.TFLOAT32<<16 | gc.TUINT8,
		gc.TFLOAT64<<16 | gc.TUINT16,
		gc.TFLOAT64<<16 | gc.TUINT8:
		cvt = gc.Types[gc.TUINT32]

		goto hard

	/*
	 * integer to float
	 */
	case gc.TINT8<<16 | gc.TFLOAT32,
		gc.TINT16<<16 | gc.TFLOAT32,
		gc.TINT32<<16 | gc.TFLOAT32:
		a = arm64.ASCVTFWS

		goto rdst

	case gc.TINT8<<16 | gc.TFLOAT64,
		gc.TINT16<<16 | gc.TFLOAT64,
		gc.TINT32<<16 | gc.TFLOAT64:
		a = arm64.ASCVTFWD

		goto rdst

	case gc.TINT64<<16 | gc.TFLOAT32:
		a = arm64.ASCVTFS
		goto rdst

	case gc.TINT64<<16 | gc.TFLOAT64:
		a = arm64.ASCVTFD
		goto rdst

	case gc.TUINT8<<16 | gc.TFLOAT32,
		gc.TUINT16<<16 | gc.TFLOAT32,
		gc.TUINT32<<16 | gc.TFLOAT32:
		a = arm64.AUCVTFWS

		goto rdst

	case gc.TUINT8<<16 | gc.TFLOAT64,
		gc.TUINT16<<16 | gc.TFLOAT64,
		gc.TUINT32<<16 | gc.TFLOAT64:
		a = arm64.AUCVTFWD

		goto rdst

	case gc.TUINT64<<16 | gc.TFLOAT32:
		a = arm64.AUCVTFS
		goto rdst

	case gc.TUINT64<<16 | gc.TFLOAT64:
		a = arm64.AUCVTFD
		goto rdst

		/*
		 * float to float
		 */
	case gc.TFLOAT32<<16 | gc.TFLOAT32:
		a = arm64.AFMOVS

	case gc.TFLOAT64<<16 | gc.TFLOAT64:
		a = arm64.AFMOVD

	case gc.TFLOAT32<<16 | gc.TFLOAT64:
		a = arm64.AFCVTSD
		goto rdst

	case gc.TFLOAT64<<16 | gc.TFLOAT32:
		a = arm64.AFCVTDS
		goto rdst
	}

	gins(a, f, t)
	return

	// requires register destination
rdst:
	regalloc(&r1, t.Type, t)

	gins(a, f, &r1)
	gmove(&r1, t)
	regfree(&r1)
	return

	// requires register intermediate
hard:
	regalloc(&r1, cvt, t)

	gmove(f, &r1)
	gmove(&r1, t)
	regfree(&r1)
	return
}

/*
 * generate one instruction:
 *	as f, t
 */
func gins(as int, f *gc.Node, t *gc.Node) *obj.Prog {
	// TODO(austin): Add self-move test like in 6g (but be careful
	// of truncation moves)

	af := obj.Addr(obj.Addr{})

	at := obj.Addr(obj.Addr{})
	if f != nil {
		af = gc.Naddr(f)
	}
	if t != nil {
		at = gc.Naddr(t)
	}
	p := (*obj.Prog)(gc.Prog(as))
	if f != nil {
		p.From = af
	}
	if t != nil {
		p.To = at
	}
	if gc.Debug['g'] != 0 {
		fmt.Printf("%v\n", p)
	}

	w := int32(0)
	switch as {
	case arm64.AMOVB,
		arm64.AMOVBU:
		w = 1

	case arm64.AMOVH,
		arm64.AMOVHU:
		w = 2

	case arm64.AMOVW,
		arm64.AMOVWU:
		w = 4

	case arm64.AMOVD:
		if af.Type == obj.TYPE_CONST || af.Type == obj.TYPE_ADDR {
			break
		}
		w = 8
	}

	if w != 0 && ((f != nil && af.Width < int64(w)) || (t != nil && at.Type != obj.TYPE_REG && at.Width > int64(w))) {
		gc.Dump("f", f)
		gc.Dump("t", t)
		gc.Fatal("bad width: %v (%d, %d)\n", p, af.Width, at.Width)
	}

	return p
}

func fixlargeoffset(n *gc.Node) {
	if n == nil {
		return
	}
	if n.Op != gc.OINDREG {
		return
	}
	if -4096 <= n.Xoffset && n.Xoffset < 4096 {
		return
	}
	a := gc.Node(*n)
	a.Op = gc.OREGISTER
	a.Type = gc.Types[gc.Tptr]
	a.Xoffset = 0
	gc.Cgen_checknil(&a)
	ginscon(optoas(gc.OADD, gc.Types[gc.Tptr]), n.Xoffset, &a)
	n.Xoffset = 0
}

/*
 * insert n into reg slot of p
 */
func raddr(n *gc.Node, p *obj.Prog) {
	var a obj.Addr

	a = gc.Naddr(n)
	if a.Type != obj.TYPE_REG {
		if n != nil {
			gc.Fatal("bad in raddr: %v", gc.Oconv(int(n.Op), 0))
		} else {
			gc.Fatal("bad in raddr: <null>")
		}
		p.Reg = 0
	} else {
		p.Reg = a.Reg
	}
}

func gcmp(as int, lhs *gc.Node, rhs *gc.Node) *obj.Prog {
	if lhs.Op != gc.OREGISTER {
		gc.Fatal("bad operands to gcmp: %v %v", gc.Oconv(int(lhs.Op), 0), gc.Oconv(int(rhs.Op), 0))
	}

	p := gins(as, rhs, nil)
	raddr(lhs, p)
	return p
}

/*
 * return Axxx for Oxxx on type t.
 */
func optoas(op int, t *gc.Type) int {
	if t == nil {
		gc.Fatal("optoas: t is nil")
	}

	a := int(obj.AXXX)
	switch uint32(op)<<16 | uint32(gc.Simtype[t.Etype]) {
	default:
		gc.Fatal("optoas: no entry for op=%v type=%v", gc.Oconv(int(op), 0), gc.Tconv(t, 0))

	case gc.OEQ<<16 | gc.TBOOL,
		gc.OEQ<<16 | gc.TINT8,
		gc.OEQ<<16 | gc.TUINT8,
		gc.OEQ<<16 | gc.TINT16,
		gc.OEQ<<16 | gc.TUINT16,
		gc.OEQ<<16 | gc.TINT32,
		gc.OEQ<<16 | gc.TUINT32,
		gc.OEQ<<16 | gc.TINT64,
		gc.OEQ<<16 | gc.TUINT64,
		gc.OEQ<<16 | gc.TPTR32,
		gc.OEQ<<16 | gc.TPTR64,
		gc.OEQ<<16 | gc.TFLOAT32,
		gc.OEQ<<16 | gc.TFLOAT64:
		a = arm64.ABEQ

	case gc.ONE<<16 | gc.TBOOL,
		gc.ONE<<16 | gc.TINT8,
		gc.ONE<<16 | gc.TUINT8,
		gc.ONE<<16 | gc.TINT16,
		gc.ONE<<16 | gc.TUINT16,
		gc.ONE<<16 | gc.TINT32,
		gc.ONE<<16 | gc.TUINT32,
		gc.ONE<<16 | gc.TINT64,
		gc.ONE<<16 | gc.TUINT64,
		gc.ONE<<16 | gc.TPTR32,
		gc.ONE<<16 | gc.TPTR64,
		gc.ONE<<16 | gc.TFLOAT32,
		gc.ONE<<16 | gc.TFLOAT64:
		a = arm64.ABNE

	case gc.OLT<<16 | gc.TINT8,
		gc.OLT<<16 | gc.TINT16,
		gc.OLT<<16 | gc.TINT32,
		gc.OLT<<16 | gc.TINT64:
		a = arm64.ABLT

	case gc.OLT<<16 | gc.TUINT8,
		gc.OLT<<16 | gc.TUINT16,
		gc.OLT<<16 | gc.TUINT32,
		gc.OLT<<16 | gc.TUINT64,
		gc.OLT<<16 | gc.TFLOAT32,
		gc.OLT<<16 | gc.TFLOAT64:
		a = arm64.ABLO

	case gc.OLE<<16 | gc.TINT8,
		gc.OLE<<16 | gc.TINT16,
		gc.OLE<<16 | gc.TINT32,
		gc.OLE<<16 | gc.TINT64:
		a = arm64.ABLE

	case gc.OLE<<16 | gc.TUINT8,
		gc.OLE<<16 | gc.TUINT16,
		gc.OLE<<16 | gc.TUINT32,
		gc.OLE<<16 | gc.TUINT64,
		gc.OLE<<16 | gc.TFLOAT32,
		gc.OLE<<16 | gc.TFLOAT64:
		a = arm64.ABLS

	case gc.OGT<<16 | gc.TINT8,
		gc.OGT<<16 | gc.TINT16,
		gc.OGT<<16 | gc.TINT32,
		gc.OGT<<16 | gc.TINT64,
		gc.OGT<<16 | gc.TFLOAT32,
		gc.OGT<<16 | gc.TFLOAT64:
		a = arm64.ABGT

	case gc.OGT<<16 | gc.TUINT8,
		gc.OGT<<16 | gc.TUINT16,
		gc.OGT<<16 | gc.TUINT32,
		gc.OGT<<16 | gc.TUINT64:
		a = arm64.ABHI

	case gc.OGE<<16 | gc.TINT8,
		gc.OGE<<16 | gc.TINT16,
		gc.OGE<<16 | gc.TINT32,
		gc.OGE<<16 | gc.TINT64,
		gc.OGE<<16 | gc.TFLOAT32,
		gc.OGE<<16 | gc.TFLOAT64:
		a = arm64.ABGE

	case gc.OGE<<16 | gc.TUINT8,
		gc.OGE<<16 | gc.TUINT16,
		gc.OGE<<16 | gc.TUINT32,
		gc.OGE<<16 | gc.TUINT64:
		a = arm64.ABHS

	case gc.OCMP<<16 | gc.TBOOL,
		gc.OCMP<<16 | gc.TINT8,
		gc.OCMP<<16 | gc.TINT16,
		gc.OCMP<<16 | gc.TINT32,
		gc.OCMP<<16 | gc.TPTR32,
		gc.OCMP<<16 | gc.TINT64,
		gc.OCMP<<16 | gc.TUINT8,
		gc.OCMP<<16 | gc.TUINT16,
		gc.OCMP<<16 | gc.TUINT32,
		gc.OCMP<<16 | gc.TUINT64,
		gc.OCMP<<16 | gc.TPTR64:
		a = arm64.ACMP

	case gc.OCMP<<16 | gc.TFLOAT32:
		a = arm64.AFCMPS

	case gc.OCMP<<16 | gc.TFLOAT64:
		a = arm64.AFCMPD

	case gc.OAS<<16 | gc.TBOOL,
		gc.OAS<<16 | gc.TINT8:
		a = arm64.AMOVB

	case gc.OAS<<16 | gc.TUINT8:
		a = arm64.AMOVBU

	case gc.OAS<<16 | gc.TINT16:
		a = arm64.AMOVH

	case gc.OAS<<16 | gc.TUINT16:
		a = arm64.AMOVHU

	case gc.OAS<<16 | gc.TINT32:
		a = arm64.AMOVW

	case gc.OAS<<16 | gc.TUINT32,
		gc.OAS<<16 | gc.TPTR32:
		a = arm64.AMOVWU

	case gc.OAS<<16 | gc.TINT64,
		gc.OAS<<16 | gc.TUINT64,
		gc.OAS<<16 | gc.TPTR64:
		a = arm64.AMOVD

	case gc.OAS<<16 | gc.TFLOAT32:
		a = arm64.AFMOVS

	case gc.OAS<<16 | gc.TFLOAT64:
		a = arm64.AFMOVD

	case gc.OADD<<16 | gc.TINT8,
		gc.OADD<<16 | gc.TUINT8,
		gc.OADD<<16 | gc.TINT16,
		gc.OADD<<16 | gc.TUINT16,
		gc.OADD<<16 | gc.TINT32,
		gc.OADD<<16 | gc.TUINT32,
		gc.OADD<<16 | gc.TPTR32,
		gc.OADD<<16 | gc.TINT64,
		gc.OADD<<16 | gc.TUINT64,
		gc.OADD<<16 | gc.TPTR64:
		a = arm64.AADD

	case gc.OADD<<16 | gc.TFLOAT32:
		a = arm64.AFADDS

	case gc.OADD<<16 | gc.TFLOAT64:
		a = arm64.AFADDD

	case gc.OSUB<<16 | gc.TINT8,
		gc.OSUB<<16 | gc.TUINT8,
		gc.OSUB<<16 | gc.TINT16,
		gc.OSUB<<16 | gc.TUINT16,
		gc.OSUB<<16 | gc.TINT32,
		gc.OSUB<<16 | gc.TUINT32,
		gc.OSUB<<16 | gc.TPTR32,
		gc.OSUB<<16 | gc.TINT64,
		gc.OSUB<<16 | gc.TUINT64,
		gc.OSUB<<16 | gc.TPTR64:
		a = arm64.ASUB

	case gc.OSUB<<16 | gc.TFLOAT32:
		a = arm64.AFSUBS

	case gc.OSUB<<16 | gc.TFLOAT64:
		a = arm64.AFSUBD

	case gc.OMINUS<<16 | gc.TINT8,
		gc.OMINUS<<16 | gc.TUINT8,
		gc.OMINUS<<16 | gc.TINT16,
		gc.OMINUS<<16 | gc.TUINT16,
		gc.OMINUS<<16 | gc.TINT32,
		gc.OMINUS<<16 | gc.TUINT32,
		gc.OMINUS<<16 | gc.TPTR32,
		gc.OMINUS<<16 | gc.TINT64,
		gc.OMINUS<<16 | gc.TUINT64,
		gc.OMINUS<<16 | gc.TPTR64:
		a = arm64.ANEG

	case gc.OMINUS<<16 | gc.TFLOAT32:
		a = arm64.AFNEGS

	case gc.OMINUS<<16 | gc.TFLOAT64:
		a = arm64.AFNEGD

	case gc.OAND<<16 | gc.TINT8,
		gc.OAND<<16 | gc.TUINT8,
		gc.OAND<<16 | gc.TINT16,
		gc.OAND<<16 | gc.TUINT16,
		gc.OAND<<16 | gc.TINT32,
		gc.OAND<<16 | gc.TUINT32,
		gc.OAND<<16 | gc.TPTR32,
		gc.OAND<<16 | gc.TINT64,
		gc.OAND<<16 | gc.TUINT64,
		gc.OAND<<16 | gc.TPTR64:
		a = arm64.AAND

	case gc.OOR<<16 | gc.TINT8,
		gc.OOR<<16 | gc.TUINT8,
		gc.OOR<<16 | gc.TINT16,
		gc.OOR<<16 | gc.TUINT16,
		gc.OOR<<16 | gc.TINT32,
		gc.OOR<<16 | gc.TUINT32,
		gc.OOR<<16 | gc.TPTR32,
		gc.OOR<<16 | gc.TINT64,
		gc.OOR<<16 | gc.TUINT64,
		gc.OOR<<16 | gc.TPTR64:
		a = arm64.AORR

	case gc.OXOR<<16 | gc.TINT8,
		gc.OXOR<<16 | gc.TUINT8,
		gc.OXOR<<16 | gc.TINT16,
		gc.OXOR<<16 | gc.TUINT16,
		gc.OXOR<<16 | gc.TINT32,
		gc.OXOR<<16 | gc.TUINT32,
		gc.OXOR<<16 | gc.TPTR32,
		gc.OXOR<<16 | gc.TINT64,
		gc.OXOR<<16 | gc.TUINT64,
		gc.OXOR<<16 | gc.TPTR64:
		a = arm64.AEOR

		// TODO(minux): handle rotates
	//case CASE(OLROT, TINT8):
	//case CASE(OLROT, TUINT8):
	//case CASE(OLROT, TINT16):
	//case CASE(OLROT, TUINT16):
	//case CASE(OLROT, TINT32):
	//case CASE(OLROT, TUINT32):
	//case CASE(OLROT, TPTR32):
	//case CASE(OLROT, TINT64):
	//case CASE(OLROT, TUINT64):
	//case CASE(OLROT, TPTR64):
	//	a = 0//???; RLDC?
	//	break;

	case gc.OLSH<<16 | gc.TINT8,
		gc.OLSH<<16 | gc.TUINT8,
		gc.OLSH<<16 | gc.TINT16,
		gc.OLSH<<16 | gc.TUINT16,
		gc.OLSH<<16 | gc.TINT32,
		gc.OLSH<<16 | gc.TUINT32,
		gc.OLSH<<16 | gc.TPTR32,
		gc.OLSH<<16 | gc.TINT64,
		gc.OLSH<<16 | gc.TUINT64,
		gc.OLSH<<16 | gc.TPTR64:
		a = arm64.ALSL

	case gc.ORSH<<16 | gc.TUINT8,
		gc.ORSH<<16 | gc.TUINT16,
		gc.ORSH<<16 | gc.TUINT32,
		gc.ORSH<<16 | gc.TPTR32,
		gc.ORSH<<16 | gc.TUINT64,
		gc.ORSH<<16 | gc.TPTR64:
		a = arm64.ALSR

	case gc.ORSH<<16 | gc.TINT8,
		gc.ORSH<<16 | gc.TINT16,
		gc.ORSH<<16 | gc.TINT32,
		gc.ORSH<<16 | gc.TINT64:
		a = arm64.AASR

		// TODO(minux): handle rotates
	//case CASE(ORROTC, TINT8):
	//case CASE(ORROTC, TUINT8):
	//case CASE(ORROTC, TINT16):
	//case CASE(ORROTC, TUINT16):
	//case CASE(ORROTC, TINT32):
	//case CASE(ORROTC, TUINT32):
	//case CASE(ORROTC, TINT64):
	//case CASE(ORROTC, TUINT64):
	//	a = 0//??? RLDC??
	//	break;

	case gc.OHMUL<<16 | gc.TINT64:
		a = arm64.ASMULH

	case gc.OHMUL<<16 | gc.TUINT64,
		gc.OHMUL<<16 | gc.TPTR64:
		a = arm64.AUMULH

	case gc.OMUL<<16 | gc.TINT8,
		gc.OMUL<<16 | gc.TINT16,
		gc.OMUL<<16 | gc.TINT32:
		a = arm64.ASMULL

	case gc.OMUL<<16 | gc.TINT64:
		a = arm64.AMUL

	case gc.OMUL<<16 | gc.TUINT8,
		gc.OMUL<<16 | gc.TUINT16,
		gc.OMUL<<16 | gc.TUINT32,
		gc.OMUL<<16 | gc.TPTR32:
		// don't use word multiply, the high 32-bit are undefined.
		a = arm64.AUMULL

	case gc.OMUL<<16 | gc.TUINT64,
		gc.OMUL<<16 | gc.TPTR64:
		a = arm64.AMUL // for 64-bit multiplies, signedness doesn't matter.

	case gc.OMUL<<16 | gc.TFLOAT32:
		a = arm64.AFMULS

	case gc.OMUL<<16 | gc.TFLOAT64:
		a = arm64.AFMULD

	case gc.ODIV<<16 | gc.TINT8,
		gc.ODIV<<16 | gc.TINT16,
		gc.ODIV<<16 | gc.TINT32,
		gc.ODIV<<16 | gc.TINT64:
		a = arm64.ASDIV

	case gc.ODIV<<16 | gc.TUINT8,
		gc.ODIV<<16 | gc.TUINT16,
		gc.ODIV<<16 | gc.TUINT32,
		gc.ODIV<<16 | gc.TPTR32,
		gc.ODIV<<16 | gc.TUINT64,
		gc.ODIV<<16 | gc.TPTR64:
		a = arm64.AUDIV

	case gc.ODIV<<16 | gc.TFLOAT32:
		a = arm64.AFDIVS

	case gc.ODIV<<16 | gc.TFLOAT64:
		a = arm64.AFDIVD
	}

	return a
}

const (
	ODynam   = 1 << 0
	OAddable = 1 << 1
)

func xgen(n *gc.Node, a *gc.Node, o int) bool {
	// TODO(minux)

	return -1 != 0 /*TypeKind(100016)*/
}

func sudoclean() {
	return
}

/*
 * generate code to compute address of n,
 * a reference to a (perhaps nested) field inside
 * an array or struct.
 * return 0 on failure, 1 on success.
 * on success, leaves usable address in a.
 *
 * caller is responsible for calling sudoclean
 * after successful sudoaddable,
 * to release the register used for a.
 */
func sudoaddable(as int, n *gc.Node, a *obj.Addr) bool {
	// TODO(minux)

	*a = obj.Addr{}
	return false
}
コード例 #16
0
ファイル: ggen.go プロジェクト: bibbyflyaway/go
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

	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. %P\n", p);
			q--
		}
	}

	var p *obj.Prog
	for c > 0 {
		p = gins(arm.AMOVB, &nz, &dst)
		p.To.Type = obj.TYPE_MEM
		p.To.Offset = 1
		p.Scond |= arm.C_PBIT

		//print("2. %P\n", p);
		c--
	}

	gc.Regfree(&dst)
	gc.Regfree(&nz)
}
コード例 #17
0
ファイル: ggen.go プロジェクト: bibbyflyaway/go
/*
 * generate shift according to op, one of:
 *	res = nl << nr
 *	res = nl >> nr
 */
func cgen_shift(op int, bounded bool, nl *gc.Node, nr *gc.Node, res *gc.Node) {
	if nl.Type.Width > 4 {
		gc.Fatal("cgen_shift %v", nl.Type)
	}

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

	if op == gc.OLROT {
		v := nr.Int()
		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.Int())
		if sc == 0 {
		} else // nothing to do
		if sc >= uint64(nl.Type.Width*8) {
			if op == gc.ORSH && gc.Issigned[nl.Type.Etype] {
				gshift(arm.AMOVW, &n1, arm.SHIFT_AR, int32(w), &n1)
			} else {
				gins(arm.AEOR, &n1, &n1)
			}
		} else {
			if op == gc.ORSH && gc.Issigned[nl.Type.Etype] {
				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)
	} else {
		if nl.Ullman >= nr.Ullman {
			gc.Regalloc(&n2, nl.Type, res)
			gc.Cgen(nl, &n2)
			gc.Regalloc(&n1, nr.Type, nil)
			gc.Cgen(nr, &n1)
		} else {
			gc.Regalloc(&n1, nr.Type, nil)
			gc.Cgen(nr, &n1)
			gc.Regalloc(&n2, nl.Type, res)
			gc.Cgen(nl, &n2)
		}
	}

	// test for shift being 0
	gins(arm.ATST, &n1, nil)

	p3 := gc.Gbranch(arm.ABEQ, nil, -1)

	// test and fix up large shifts
	// TODO: if(!bounded), don't emit some of this.
	gc.Regalloc(&n3, tr, nil)

	gc.Nodconst(&t, gc.Types[gc.TUINT32], int64(w))
	gmove(&t, &n3)
	gins(arm.ACMP, &n1, &n3)
	if op == gc.ORSH {
		var p1 *obj.Prog
		var p2 *obj.Prog
		if gc.Issigned[nl.Type.Etype] {
			p1 = gshift(arm.AMOVW, &n2, arm.SHIFT_AR, int32(w)-1, &n2)
			p2 = gregshift(arm.AMOVW, &n2, arm.SHIFT_AR, &n1, &n2)
		} else {
			p1 = gins(arm.AEOR, &n2, &n2)
			p2 = gregshift(arm.AMOVW, &n2, arm.SHIFT_LR, &n1, &n2)
		}

		p1.Scond = arm.C_SCOND_HS
		p2.Scond = arm.C_SCOND_LO
	} else {
		p1 := gins(arm.AEOR, &n2, &n2)
		p2 := gregshift(arm.AMOVW, &n2, arm.SHIFT_LL, &n1, &n2)
		p1.Scond = arm.C_SCOND_HS
		p2.Scond = arm.C_SCOND_LO
	}

	gc.Regfree(&n3)

	gc.Patch(p3, gc.Pc)

	// Left-shift of smaller word must be sign/zero-extended.
	if w < 32 && op == gc.OLSH {
		gins(optoas(gc.OAS, nl.Type), &n2, &n2)
	}
	gmove(&n2, res)

	gc.Regfree(&n1)
	gc.Regfree(&n2)
}
コード例 #18
0
ファイル: ggen.go プロジェクト: klueska/go-akaros
/*
 * generate division according to op, one of:
 *	res = nl / nr
 *	res = nl % nr
 */
func cgen_div(op int, nl *gc.Node, nr *gc.Node, res *gc.Node) {
	var w int

	if nr.Op != gc.OLITERAL {
		goto longdiv
	}
	w = int(nl.Type.Width * 8)

	// Front end handled 32-bit division. We only need to handle 64-bit.
	// try to do division by multiply by (2^w)/d
	// see hacker's delight chapter 10
	switch gc.Simtype[nl.Type.Etype] {
	default:
		goto longdiv

	case gc.TUINT64:
		var m gc.Magic
		m.W = w
		m.Ud = uint64(gc.Mpgetfix(nr.Val.U.Xval))
		gc.Umagic(&m)
		if m.Bad != 0 {
			break
		}
		if op == gc.OMOD {
			goto longmod
		}

		var n1 gc.Node
		cgenr(nl, &n1, nil)
		var n2 gc.Node
		gc.Nodconst(&n2, nl.Type, int64(m.Um))
		var n3 gc.Node
		regalloc(&n3, nl.Type, res)
		cgen_hmul(&n1, &n2, &n3)

		if m.Ua != 0 {
			// need to add numerator accounting for overflow
			gins(optoas(gc.OADD, nl.Type), &n1, &n3)

			gc.Nodconst(&n2, nl.Type, 1)
			gins(optoas(gc.ORROTC, nl.Type), &n2, &n3)
			gc.Nodconst(&n2, nl.Type, int64(m.S)-1)
			gins(optoas(gc.ORSH, nl.Type), &n2, &n3)
		} else {
			gc.Nodconst(&n2, nl.Type, int64(m.S))
			gins(optoas(gc.ORSH, nl.Type), &n2, &n3) // shift dx
		}

		gmove(&n3, res)
		regfree(&n1)
		regfree(&n3)
		return

	case gc.TINT64:
		var m gc.Magic
		m.W = w
		m.Sd = gc.Mpgetfix(nr.Val.U.Xval)
		gc.Smagic(&m)
		if m.Bad != 0 {
			break
		}
		if op == gc.OMOD {
			goto longmod
		}

		var n1 gc.Node
		cgenr(nl, &n1, res)
		var n2 gc.Node
		gc.Nodconst(&n2, nl.Type, m.Sm)
		var n3 gc.Node
		regalloc(&n3, nl.Type, nil)
		cgen_hmul(&n1, &n2, &n3)

		if m.Sm < 0 {
			// need to add numerator
			gins(optoas(gc.OADD, nl.Type), &n1, &n3)
		}

		gc.Nodconst(&n2, nl.Type, int64(m.S))
		gins(optoas(gc.ORSH, nl.Type), &n2, &n3) // shift n3

		gc.Nodconst(&n2, nl.Type, int64(w)-1)

		gins(optoas(gc.ORSH, nl.Type), &n2, &n1) // -1 iff num is neg
		gins(optoas(gc.OSUB, nl.Type), &n1, &n3) // added

		if m.Sd < 0 {
			// this could probably be removed
			// by factoring it into the multiplier
			gins(optoas(gc.OMINUS, nl.Type), nil, &n3)
		}

		gmove(&n3, res)
		regfree(&n1)
		regfree(&n3)
		return
	}

	goto longdiv

	// division and mod using (slow) hardware instruction
longdiv:
	dodiv(op, nl, nr, res)

	return

	// mod using formula A%B = A-(A/B*B) but
	// we know that there is a fast algorithm for A/B
longmod:
	var n1 gc.Node
	regalloc(&n1, nl.Type, res)

	cgen(nl, &n1)
	var n2 gc.Node
	regalloc(&n2, nl.Type, nil)
	cgen_div(gc.ODIV, &n1, nr, &n2)
	a := optoas(gc.OMUL, nl.Type)
	if w == 8 {
		// use 2-operand 16-bit multiply
		// because there is no 2-operand 8-bit multiply
		a = x86.AIMULW
	}

	if !gc.Smallintconst(nr) {
		var n3 gc.Node
		regalloc(&n3, nl.Type, nil)
		cgen(nr, &n3)
		gins(a, &n3, &n2)
		regfree(&n3)
	} else {
		gins(a, nr, &n2)
	}
	gins(optoas(gc.OSUB, nl.Type), &n2, &n1)
	gmove(&n1, res)
	regfree(&n1)
	regfree(&n2)
}
コード例 #19
0
ファイル: gsubr.go プロジェクト: xslonepiece/goios
/*
 * generate
 *	as $c, n
 */
func ginscon(as int, c int64, n2 *gc.Node) {
	var n1 gc.Node
	gc.Nodconst(&n1, gc.Types[gc.TINT32], c)
	gins(as, &n1, n2)
}
コード例 #20
0
ファイル: cgen.go プロジェクト: klueska/go-akaros
/*
 * allocate a register (reusing res if possible) and generate
 * a = &n
 * The caller must call regfree(a).
 * The generated code checks that the result is not nil.
 */
func agenr(n *gc.Node, a *gc.Node, res *gc.Node) {
	if gc.Debug['g'] != 0 {
		gc.Dump("agenr-n", n)
	}

	nl := n.Left
	nr := n.Right

	switch n.Op {
	case gc.ODOT,
		gc.ODOTPTR,
		gc.OCALLFUNC,
		gc.OCALLMETH,
		gc.OCALLINTER:
		var n1 gc.Node
		igen(n, &n1, res)
		regalloc(a, gc.Types[gc.Tptr], &n1)
		agen(&n1, a)
		regfree(&n1)

	case gc.OIND:
		cgenr(n.Left, a, res)
		gc.Cgen_checknil(a)

	case gc.OINDEX:
		var p2 *obj.Prog // to be patched to panicindex.
		w := uint32(n.Type.Width)

		//bounded = debug['B'] || n->bounded;
		var n3 gc.Node
		var n1 gc.Node
		if nr.Addable != 0 {
			var tmp gc.Node
			if !gc.Isconst(nr, gc.CTINT) {
				gc.Tempname(&tmp, gc.Types[gc.TINT64])
			}
			if !gc.Isconst(nl, gc.CTSTR) {
				agenr(nl, &n3, res)
			}
			if !gc.Isconst(nr, gc.CTINT) {
				cgen(nr, &tmp)
				regalloc(&n1, tmp.Type, nil)
				gmove(&tmp, &n1)
			}
		} else if nl.Addable != 0 {
			if !gc.Isconst(nr, gc.CTINT) {
				var tmp gc.Node
				gc.Tempname(&tmp, gc.Types[gc.TINT64])
				cgen(nr, &tmp)
				regalloc(&n1, tmp.Type, nil)
				gmove(&tmp, &n1)
			}

			if !gc.Isconst(nl, gc.CTSTR) {
				agenr(nl, &n3, res)
			}
		} else {
			var tmp gc.Node
			gc.Tempname(&tmp, gc.Types[gc.TINT64])
			cgen(nr, &tmp)
			nr = &tmp
			if !gc.Isconst(nl, gc.CTSTR) {
				agenr(nl, &n3, res)
			}
			regalloc(&n1, tmp.Type, nil)
			gins(optoas(gc.OAS, tmp.Type), &tmp, &n1)
		}

		// &a is in &n3 (allocated in res)
		// i is in &n1 (if not constant)
		// w is width

		// constant index
		if gc.Isconst(nr, gc.CTINT) {
			if gc.Isconst(nl, gc.CTSTR) {
				gc.Fatal("constant string constant index")
			}
			v := uint64(gc.Mpgetfix(nr.Val.U.Xval))
			if gc.Isslice(nl.Type) || nl.Type.Etype == gc.TSTRING {
				if gc.Debug['B'] == 0 && !n.Bounded {
					n1 = n3
					n1.Op = gc.OINDREG
					n1.Type = gc.Types[gc.Tptr]
					n1.Xoffset = int64(gc.Array_nel)
					var n4 gc.Node
					regalloc(&n4, n1.Type, nil)
					gmove(&n1, &n4)
					ginscon2(optoas(gc.OCMP, gc.Types[gc.TUINT64]), &n4, int64(v))
					regfree(&n4)
					p1 := gc.Gbranch(optoas(gc.OGT, gc.Types[gc.TUINT64]), nil, +1)
					ginscall(gc.Panicindex, 0)
					gc.Patch(p1, gc.Pc)
				}

				n1 = n3
				n1.Op = gc.OINDREG
				n1.Type = gc.Types[gc.Tptr]
				n1.Xoffset = int64(gc.Array_array)
				gmove(&n1, &n3)
			}

			if v*uint64(w) != 0 {
				ginscon(optoas(gc.OADD, gc.Types[gc.Tptr]), int64(v*uint64(w)), &n3)
			}

			*a = n3
			break
		}

		var n2 gc.Node
		regalloc(&n2, gc.Types[gc.TINT64], &n1) // i
		gmove(&n1, &n2)
		regfree(&n1)

		var n4 gc.Node
		if gc.Debug['B'] == 0 && !n.Bounded {
			// check bounds
			if gc.Isconst(nl, gc.CTSTR) {
				gc.Nodconst(&n4, gc.Types[gc.TUINT64], int64(len(nl.Val.U.Sval)))
			} else if gc.Isslice(nl.Type) || nl.Type.Etype == gc.TSTRING {
				n1 = n3
				n1.Op = gc.OINDREG
				n1.Type = gc.Types[gc.Tptr]
				n1.Xoffset = int64(gc.Array_nel)
				regalloc(&n4, gc.Types[gc.TUINT64], nil)
				gmove(&n1, &n4)
			} else {
				if nl.Type.Bound < (1<<15)-1 {
					gc.Nodconst(&n4, gc.Types[gc.TUINT64], nl.Type.Bound)
				} else {
					regalloc(&n4, gc.Types[gc.TUINT64], nil)
					p1 := gins(ppc64.AMOVD, nil, &n4)
					p1.From.Type = obj.TYPE_CONST
					p1.From.Offset = nl.Type.Bound
				}
			}

			gins(optoas(gc.OCMP, gc.Types[gc.TUINT64]), &n2, &n4)
			if n4.Op == gc.OREGISTER {
				regfree(&n4)
			}
			p1 := gc.Gbranch(optoas(gc.OLT, gc.Types[gc.TUINT64]), nil, +1)
			if p2 != nil {
				gc.Patch(p2, gc.Pc)
			}
			ginscall(gc.Panicindex, 0)
			gc.Patch(p1, gc.Pc)
		}

		if gc.Isconst(nl, gc.CTSTR) {
			regalloc(&n3, gc.Types[gc.Tptr], res)
			p1 := gins(ppc64.AMOVD, nil, &n3)
			gc.Datastring(nl.Val.U.Sval, &p1.From)
			p1.From.Type = obj.TYPE_ADDR
		} else if gc.Isslice(nl.Type) || nl.Type.Etype == gc.TSTRING {
			n1 = n3
			n1.Op = gc.OINDREG
			n1.Type = gc.Types[gc.Tptr]
			n1.Xoffset = int64(gc.Array_array)
			gmove(&n1, &n3)
		}

		if w == 0 {
		} else // nothing to do
		if w == 1 {
			/* w already scaled */
			gins(optoas(gc.OADD, gc.Types[gc.Tptr]), &n2, &n3)
			/* else if(w == 2 || w == 4 || w == 8) {
				// TODO(minux): scale using shift
			} */
		} else {
			regalloc(&n4, gc.Types[gc.TUINT64], nil)
			gc.Nodconst(&n1, gc.Types[gc.TUINT64], int64(w))
			gmove(&n1, &n4)
			gins(optoas(gc.OMUL, gc.Types[gc.TUINT64]), &n4, &n2)
			gins(optoas(gc.OADD, gc.Types[gc.Tptr]), &n2, &n3)
			regfree(&n4)
		}

		*a = n3
		regfree(&n2)

	default:
		regalloc(a, gc.Types[gc.Tptr], res)
		agen(n, a)
	}
}
コード例 #21
0
ファイル: cgen.go プロジェクト: klueska/go-akaros
/*
 * generate:
 *	res = n;
 * simplifies and calls gmove.
 */
func cgen(n *gc.Node, res *gc.Node) {
	//print("cgen %N(%d) -> %N(%d)\n", n, n->addable, res, res->addable);
	if gc.Debug['g'] != 0 {
		gc.Dump("\ncgen-n", n)
		gc.Dump("cgen-res", res)
	}

	if n == nil || n.Type == nil {
		return
	}

	if res == nil || res.Type == nil {
		gc.Fatal("cgen: res nil")
	}

	for n.Op == gc.OCONVNOP {
		n = n.Left
	}

	switch n.Op {
	case gc.OSLICE,
		gc.OSLICEARR,
		gc.OSLICESTR,
		gc.OSLICE3,
		gc.OSLICE3ARR:
		if res.Op != gc.ONAME || res.Addable == 0 {
			var n1 gc.Node
			gc.Tempname(&n1, n.Type)
			gc.Cgen_slice(n, &n1)
			cgen(&n1, res)
		} else {
			gc.Cgen_slice(n, res)
		}
		return

	case gc.OEFACE:
		if res.Op != gc.ONAME || res.Addable == 0 {
			var n1 gc.Node
			gc.Tempname(&n1, n.Type)
			gc.Cgen_eface(n, &n1)
			cgen(&n1, res)
		} else {
			gc.Cgen_eface(n, res)
		}
		return
	}

	if n.Ullman >= gc.UINF {
		if n.Op == gc.OINDREG {
			gc.Fatal("cgen: this is going to misscompile")
		}
		if res.Ullman >= gc.UINF {
			var n1 gc.Node
			gc.Tempname(&n1, n.Type)
			cgen(n, &n1)
			cgen(&n1, res)
			return
		}
	}

	if gc.Isfat(n.Type) {
		if n.Type.Width < 0 {
			gc.Fatal("forgot to compute width for %v", gc.Tconv(n.Type, 0))
		}
		sgen(n, res, n.Type.Width)
		return
	}

	if res.Addable == 0 {
		if n.Ullman > res.Ullman {
			var n1 gc.Node
			regalloc(&n1, n.Type, res)
			cgen(n, &n1)
			if n1.Ullman > res.Ullman {
				gc.Dump("n1", &n1)
				gc.Dump("res", res)
				gc.Fatal("loop in cgen")
			}

			cgen(&n1, res)
			regfree(&n1)
			return
		}

		var f int
		if res.Ullman >= gc.UINF {
			goto gen
		}

		if gc.Complexop(n, res) {
			gc.Complexgen(n, res)
			return
		}

		f = 1 // gen thru register
		switch n.Op {
		case gc.OLITERAL:
			if gc.Smallintconst(n) {
				f = 0
			}

		case gc.OREGISTER:
			f = 0
		}

		if !gc.Iscomplex[n.Type.Etype] {
			a := optoas(gc.OAS, res.Type)
			var addr obj.Addr
			if sudoaddable(a, res, &addr) {
				var p1 *obj.Prog
				if f != 0 {
					var n2 gc.Node
					regalloc(&n2, res.Type, nil)
					cgen(n, &n2)
					p1 = gins(a, &n2, nil)
					regfree(&n2)
				} else {
					p1 = gins(a, n, nil)
				}
				p1.To = addr
				if gc.Debug['g'] != 0 {
					fmt.Printf("%v [ignore previous line]\n", p1)
				}
				sudoclean()
				return
			}
		}

	gen:
		var n1 gc.Node
		igen(res, &n1, nil)
		cgen(n, &n1)
		regfree(&n1)
		return
	}

	// update addressability for string, slice
	// can't do in walk because n->left->addable
	// changes if n->left is an escaping local variable.
	switch n.Op {
	case gc.OSPTR,
		gc.OLEN:
		if gc.Isslice(n.Left.Type) || gc.Istype(n.Left.Type, gc.TSTRING) {
			n.Addable = n.Left.Addable
		}

	case gc.OCAP:
		if gc.Isslice(n.Left.Type) {
			n.Addable = n.Left.Addable
		}

	case gc.OITAB:
		n.Addable = n.Left.Addable
	}

	if gc.Complexop(n, res) {
		gc.Complexgen(n, res)
		return
	}

	// if both are addressable, move
	if n.Addable != 0 {
		if n.Op == gc.OREGISTER || res.Op == gc.OREGISTER {
			gmove(n, res)
		} else {
			var n1 gc.Node
			regalloc(&n1, n.Type, nil)
			gmove(n, &n1)
			cgen(&n1, res)
			regfree(&n1)
		}

		return
	}

	nl := n.Left
	nr := n.Right

	if nl != nil && nl.Ullman >= gc.UINF {
		if nr != nil && nr.Ullman >= gc.UINF {
			var n1 gc.Node
			gc.Tempname(&n1, nl.Type)
			cgen(nl, &n1)
			n2 := *n
			n2.Left = &n1
			cgen(&n2, res)
			return
		}
	}

	if !gc.Iscomplex[n.Type.Etype] {
		a := optoas(gc.OAS, n.Type)
		var addr obj.Addr
		if sudoaddable(a, n, &addr) {
			if res.Op == gc.OREGISTER {
				p1 := gins(a, nil, res)
				p1.From = addr
			} else {
				var n2 gc.Node
				regalloc(&n2, n.Type, nil)
				p1 := gins(a, nil, &n2)
				p1.From = addr
				gins(a, &n2, res)
				regfree(&n2)
			}

			sudoclean()
			return
		}
	}

	// TODO(minux): we shouldn't reverse FP comparisons, but then we need to synthesize
	// OGE, OLE, and ONE ourselves.
	// if(nl != N && isfloat[n->type->etype] && isfloat[nl->type->etype]) goto flt;

	var a int
	switch n.Op {
	default:
		gc.Dump("cgen", n)
		gc.Fatal("cgen: unknown op %v", gc.Nconv(n, obj.FmtShort|obj.FmtSign))

		// these call bgen to get a bool value
	case gc.OOROR,
		gc.OANDAND,
		gc.OEQ,
		gc.ONE,
		gc.OLT,
		gc.OLE,
		gc.OGE,
		gc.OGT,
		gc.ONOT:
		p1 := gc.Gbranch(ppc64.ABR, nil, 0)

		p2 := gc.Pc
		gmove(gc.Nodbool(true), res)
		p3 := gc.Gbranch(ppc64.ABR, nil, 0)
		gc.Patch(p1, gc.Pc)
		bgen(n, true, 0, p2)
		gmove(gc.Nodbool(false), res)
		gc.Patch(p3, gc.Pc)
		return

	case gc.OPLUS:
		cgen(nl, res)
		return

		// unary
	case gc.OCOM:
		a := optoas(gc.OXOR, nl.Type)

		var n1 gc.Node
		regalloc(&n1, nl.Type, nil)
		cgen(nl, &n1)
		var n2 gc.Node
		gc.Nodconst(&n2, nl.Type, -1)
		gins(a, &n2, &n1)
		gmove(&n1, res)
		regfree(&n1)
		return

	case gc.OMINUS:
		if gc.Isfloat[nl.Type.Etype] {
			nr = gc.Nodintconst(-1)
			gc.Convlit(&nr, n.Type)
			a = optoas(gc.OMUL, nl.Type)
			goto sbop
		}

		a := optoas(int(n.Op), nl.Type)
		// unary
		var n1 gc.Node
		regalloc(&n1, nl.Type, res)

		cgen(nl, &n1)
		gins(a, nil, &n1)
		gmove(&n1, res)
		regfree(&n1)
		return

		// symmetric binary
	case gc.OAND,
		gc.OOR,
		gc.OXOR,
		gc.OADD,
		gc.OMUL:
		a = optoas(int(n.Op), nl.Type)

		goto sbop

		// asymmetric binary
	case gc.OSUB:
		a = optoas(int(n.Op), nl.Type)

		goto abop

	case gc.OHMUL:
		cgen_hmul(nl, nr, res)

	case gc.OCONV:
		if n.Type.Width > nl.Type.Width {
			// If loading from memory, do conversion during load,
			// so as to avoid use of 8-bit register in, say, int(*byteptr).
			switch nl.Op {
			case gc.ODOT,
				gc.ODOTPTR,
				gc.OINDEX,
				gc.OIND,
				gc.ONAME:
				var n1 gc.Node
				igen(nl, &n1, res)
				var n2 gc.Node
				regalloc(&n2, n.Type, res)
				gmove(&n1, &n2)
				gmove(&n2, res)
				regfree(&n2)
				regfree(&n1)
				return
			}
		}

		var n1 gc.Node
		regalloc(&n1, nl.Type, res)
		var n2 gc.Node
		regalloc(&n2, n.Type, &n1)
		cgen(nl, &n1)

		// if we do the conversion n1 -> n2 here
		// reusing the register, then gmove won't
		// have to allocate its own register.
		gmove(&n1, &n2)

		gmove(&n2, res)
		regfree(&n2)
		regfree(&n1)

	case gc.ODOT,
		gc.ODOTPTR,
		gc.OINDEX,
		gc.OIND,
		gc.ONAME: // PHEAP or PPARAMREF var
		var n1 gc.Node
		igen(n, &n1, res)

		gmove(&n1, res)
		regfree(&n1)

		// interface table is first word of interface value
	case gc.OITAB:
		var n1 gc.Node
		igen(nl, &n1, res)

		n1.Type = n.Type
		gmove(&n1, res)
		regfree(&n1)

		// pointer is the first word of string or slice.
	case gc.OSPTR:
		if gc.Isconst(nl, gc.CTSTR) {
			var n1 gc.Node
			regalloc(&n1, gc.Types[gc.Tptr], res)
			p1 := gins(ppc64.AMOVD, nil, &n1)
			gc.Datastring(nl.Val.U.Sval, &p1.From)
			gmove(&n1, res)
			regfree(&n1)
			break
		}

		var n1 gc.Node
		igen(nl, &n1, res)
		n1.Type = n.Type
		gmove(&n1, res)
		regfree(&n1)

	case gc.OLEN:
		if gc.Istype(nl.Type, gc.TMAP) || gc.Istype(nl.Type, gc.TCHAN) {
			// map and chan have len in the first int-sized word.
			// a zero pointer means zero length
			var n1 gc.Node
			regalloc(&n1, gc.Types[gc.Tptr], res)

			cgen(nl, &n1)

			var n2 gc.Node
			gc.Nodconst(&n2, gc.Types[gc.Tptr], 0)
			gins(optoas(gc.OCMP, gc.Types[gc.Tptr]), &n1, &n2)
			p1 := gc.Gbranch(optoas(gc.OEQ, gc.Types[gc.Tptr]), nil, 0)

			n2 = n1
			n2.Op = gc.OINDREG
			n2.Type = gc.Types[gc.Simtype[gc.TINT]]
			gmove(&n2, &n1)

			gc.Patch(p1, gc.Pc)

			gmove(&n1, res)
			regfree(&n1)
			break
		}

		if gc.Istype(nl.Type, gc.TSTRING) || gc.Isslice(nl.Type) {
			// both slice and string have len one pointer into the struct.
			// a zero pointer means zero length
			var n1 gc.Node
			igen(nl, &n1, res)

			n1.Type = gc.Types[gc.Simtype[gc.TUINT]]
			n1.Xoffset += int64(gc.Array_nel)
			gmove(&n1, res)
			regfree(&n1)
			break
		}

		gc.Fatal("cgen: OLEN: unknown type %v", gc.Tconv(nl.Type, obj.FmtLong))

	case gc.OCAP:
		if gc.Istype(nl.Type, gc.TCHAN) {
			// chan has cap in the second int-sized word.
			// a zero pointer means zero length
			var n1 gc.Node
			regalloc(&n1, gc.Types[gc.Tptr], res)

			cgen(nl, &n1)

			var n2 gc.Node
			gc.Nodconst(&n2, gc.Types[gc.Tptr], 0)
			gins(optoas(gc.OCMP, gc.Types[gc.Tptr]), &n1, &n2)
			p1 := gc.Gbranch(optoas(gc.OEQ, gc.Types[gc.Tptr]), nil, 0)

			n2 = n1
			n2.Op = gc.OINDREG
			n2.Xoffset = int64(gc.Widthint)
			n2.Type = gc.Types[gc.Simtype[gc.TINT]]
			gmove(&n2, &n1)

			gc.Patch(p1, gc.Pc)

			gmove(&n1, res)
			regfree(&n1)
			break
		}

		if gc.Isslice(nl.Type) {
			var n1 gc.Node
			igen(nl, &n1, res)
			n1.Type = gc.Types[gc.Simtype[gc.TUINT]]
			n1.Xoffset += int64(gc.Array_cap)
			gmove(&n1, res)
			regfree(&n1)
			break
		}

		gc.Fatal("cgen: OCAP: unknown type %v", gc.Tconv(nl.Type, obj.FmtLong))

	case gc.OADDR:
		if n.Bounded { // let race detector avoid nil checks
			gc.Disable_checknil++
		}
		agen(nl, res)
		if n.Bounded {
			gc.Disable_checknil--
		}

	case gc.OCALLMETH:
		gc.Cgen_callmeth(n, 0)
		cgen_callret(n, res)

	case gc.OCALLINTER:
		cgen_callinter(n, res, 0)
		cgen_callret(n, res)

	case gc.OCALLFUNC:
		cgen_call(n, 0)
		cgen_callret(n, res)

	case gc.OMOD,
		gc.ODIV:
		if gc.Isfloat[n.Type.Etype] {
			a = optoas(int(n.Op), nl.Type)
			goto abop
		}

		if nl.Ullman >= nr.Ullman {
			var n1 gc.Node
			regalloc(&n1, nl.Type, res)
			cgen(nl, &n1)
			cgen_div(int(n.Op), &n1, nr, res)
			regfree(&n1)
		} else {
			var n2 gc.Node
			if !gc.Smallintconst(nr) {
				regalloc(&n2, nr.Type, res)
				cgen(nr, &n2)
			} else {
				n2 = *nr
			}

			cgen_div(int(n.Op), nl, &n2, res)
			if n2.Op != gc.OLITERAL {
				regfree(&n2)
			}
		}

	case gc.OLSH,
		gc.ORSH,
		gc.OLROT:
		cgen_shift(int(n.Op), n.Bounded, nl, nr, res)
	}

	return

	/*
	 * put simplest on right - we'll generate into left
	 * and then adjust it using the computation of right.
	 * constants and variables have the same ullman
	 * count, so look for constants specially.
	 *
	 * an integer constant we can use as an immediate
	 * is simpler than a variable - we can use the immediate
	 * in the adjustment instruction directly - so it goes
	 * on the right.
	 *
	 * other constants, like big integers or floating point
	 * constants, require a mov into a register, so those
	 * might as well go on the left, so we can reuse that
	 * register for the computation.
	 */
sbop: // symmetric binary
	if nl.Ullman < nr.Ullman || (nl.Ullman == nr.Ullman && (gc.Smallintconst(nl) || (nr.Op == gc.OLITERAL && !gc.Smallintconst(nr)))) {
		r := nl
		nl = nr
		nr = r
	}

abop: // asymmetric binary
	var n1 gc.Node
	var n2 gc.Node
	if nl.Ullman >= nr.Ullman {
		regalloc(&n1, nl.Type, res)
		cgen(nl, &n1)

		/*
			 * This generates smaller code - it avoids a MOV - but it's
			 * easily 10% slower due to not being able to
			 * optimize/manipulate the move.
			 * To see, run: go test -bench . crypto/md5
			 * with and without.
			 *
				if(sudoaddable(a, nr, &addr)) {
					p1 = gins(a, N, &n1);
					p1->from = addr;
					gmove(&n1, res);
					sudoclean();
					regfree(&n1);
					goto ret;
				}
			 *
		*/
		// TODO(minux): enable using constants directly in certain instructions.
		//if(smallintconst(nr))
		//	n2 = *nr;
		//else {
		regalloc(&n2, nr.Type, nil)

		cgen(nr, &n2)
	} else //}
	{
		//if(smallintconst(nr))
		//	n2 = *nr;
		//else {
		regalloc(&n2, nr.Type, res)

		cgen(nr, &n2)

		//}
		regalloc(&n1, nl.Type, nil)

		cgen(nl, &n1)
	}

	gins(a, &n2, &n1)

	// Normalize result for types smaller than word.
	if n.Type.Width < int64(gc.Widthreg) {
		switch n.Op {
		case gc.OADD,
			gc.OSUB,
			gc.OMUL,
			gc.OLSH:
			gins(optoas(gc.OAS, n.Type), &n1, &n1)
		}
	}

	gmove(&n1, res)
	regfree(&n1)
	if n2.Op != gc.OLITERAL {
		regfree(&n2)
	}
	return
}
コード例 #22
0
ファイル: ggen.go プロジェクト: klueska/go-akaros
/*
 * generate:
 *	call f
 *	proc=-1	normal call but no return
 *	proc=0	normal call
 *	proc=1	goroutine run in new proc
 *	proc=2	defer call save away stack
  *	proc=3	normal call to C pointer (not Go func value)
*/
func ginscall(f *gc.Node, proc int) {
	if f.Type != nil {
		extra := int32(0)
		if proc == 1 || proc == 2 {
			extra = 2 * int32(gc.Widthptr)
		}
		gc.Setmaxarg(f.Type, extra)
	}

	switch proc {
	default:
		gc.Fatal("ginscall: bad proc %d", proc)

	case 0, // normal call
		-1: // normal call but no return
		if f.Op == gc.ONAME && f.Class == gc.PFUNC {
			if f == gc.Deferreturn {
				// Deferred calls will appear to be returning to
				// the CALL deferreturn(SB) that we are about to emit.
				// However, the stack trace code will show the line
				// of the instruction byte before the return PC.
				// To avoid that being an unrelated instruction,
				// insert an x86 NOP that we will have the right line number.
				// x86 NOP 0x90 is really XCHG AX, AX; use that description
				// because the NOP pseudo-instruction will be removed by
				// the linker.
				var reg gc.Node
				gc.Nodreg(&reg, gc.Types[gc.TINT], x86.REG_AX)

				gins(x86.AXCHGL, &reg, &reg)
			}

			p := gins(obj.ACALL, nil, f)
			gc.Afunclit(&p.To, f)
			if proc == -1 || gc.Noreturn(p) {
				gins(obj.AUNDEF, nil, nil)
			}
			break
		}

		var reg gc.Node
		gc.Nodreg(&reg, gc.Types[gc.Tptr], x86.REG_DX)
		var r1 gc.Node
		gc.Nodreg(&r1, gc.Types[gc.Tptr], x86.REG_BX)
		gmove(f, &reg)
		reg.Op = gc.OINDREG
		gmove(&reg, &r1)
		reg.Op = gc.OREGISTER
		gins(obj.ACALL, &reg, &r1)

	case 3: // normal call of c function pointer
		gins(obj.ACALL, nil, f)

	case 1, // call in new proc (go)
		2: // deferred call (defer)
		var stk gc.Node

		stk.Op = gc.OINDREG
		stk.Val.U.Reg = x86.REG_SP
		stk.Xoffset = 0

		// size of arguments at 0(SP)
		var con gc.Node
		gc.Nodconst(&con, gc.Types[gc.TINT32], int64(gc.Argsize(f.Type)))

		gins(x86.AMOVL, &con, &stk)

		// FuncVal* at 4(SP)
		stk.Xoffset = int64(gc.Widthptr)

		gins(x86.AMOVL, f, &stk)

		if proc == 1 {
			ginscall(gc.Newproc, 0)
		} else {
			ginscall(gc.Deferproc, 0)
		}
		if proc == 2 {
			var reg gc.Node
			gc.Nodreg(&reg, gc.Types[gc.TINT32], x86.REG_AX)
			gins(x86.ATESTL, &reg, &reg)
			p := gc.Gbranch(x86.AJEQ, nil, +1)
			cgen_ret(nil)
			gc.Patch(p, gc.Pc)
		}
	}
}
コード例 #23
0
ファイル: ggen.go プロジェクト: tidatida/go
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 q < 4 {
		// Write sequence of MOV 0, off(base) instead of using STOSL.
		// The hope is that although the code will be slightly longer,
		// the MOVs will have no dependencies and pipeline better
		// than the unrolled STOSL loop.
		// NOTE: Must use agen, not igen, so that optimizer sees address
		// being taken. We are not writing on field boundaries.
		var n1 gc.Node
		gc.Regalloc(&n1, gc.Types[gc.Tptr], nil)

		gc.Agen(nl, &n1)
		n1.Op = gc.OINDREG
		var z gc.Node
		gc.Nodconst(&z, gc.Types[gc.TUINT64], 0)
		for {
			tmp14 := q
			q--
			if tmp14 <= 0 {
				break
			}
			n1.Type = z.Type
			gins(x86.AMOVL, &z, &n1)
			n1.Xoffset += 4
		}

		gc.Nodconst(&z, gc.Types[gc.TUINT8], 0)
		for {
			tmp15 := c
			c--
			if tmp15 <= 0 {
				break
			}
			n1.Type = z.Type
			gins(x86.AMOVB, &z, &n1)
			n1.Xoffset++
		}

		gc.Regfree(&n1)
		return
	}

	var n1 gc.Node
	gc.Nodreg(&n1, gc.Types[gc.Tptr], x86.REG_DI)
	gc.Agen(nl, &n1)
	gconreg(x86.AMOVL, 0, x86.REG_AX)

	if q > 128 || (q >= 4 && gc.Nacl) {
		gconreg(x86.AMOVL, int64(q), x86.REG_CX)
		gins(x86.AREP, nil, nil)   // repeat
		gins(x86.ASTOSL, nil, nil) // STOL AL,*(DI)+
	} else if q >= 4 {
		p := gins(obj.ADUFFZERO, nil, nil)
		p.To.Type = obj.TYPE_ADDR
		p.To.Sym = gc.Linksym(gc.Pkglookup("duffzero", gc.Runtimepkg))

		// 1 and 128 = magic constants: see ../../runtime/asm_386.s
		p.To.Offset = 1 * (128 - int64(q))
	} else {
		for q > 0 {
			gins(x86.ASTOSL, nil, nil) // STOL AL,*(DI)+
			q--
		}
	}

	for c > 0 {
		gins(x86.ASTOSB, nil, nil) // STOB AL,*(DI)+
		c--
	}
}
コード例 #24
0
ファイル: ggen.go プロジェクト: xslonepiece/goios
/*
 * generate shift according to op, one of:
 *	res = nl << nr
 *	res = nl >> nr
 */
func cgen_shift(op int, bounded bool, nl *gc.Node, nr *gc.Node, res *gc.Node) {
	a := optoas(op, nl.Type)

	if nr.Op == gc.OLITERAL {
		var n1 gc.Node
		gc.Regalloc(&n1, nl.Type, res)
		gc.Cgen(nl, &n1)
		sc := uint64(gc.Mpgetfix(nr.Val.U.Xval))
		if sc >= uint64(nl.Type.Width*8) {
			// large shift gets 2 shifts by width-1
			var n3 gc.Node
			gc.Nodconst(&n3, gc.Types[gc.TUINT32], nl.Type.Width*8-1)

			gins(a, &n3, &n1)
			gins(a, &n3, &n1)
		} else {
			gins(a, nr, &n1)
		}
		gmove(&n1, res)
		gc.Regfree(&n1)
		return
	}

	if nl.Ullman >= gc.UINF {
		var n4 gc.Node
		gc.Tempname(&n4, nl.Type)
		gc.Cgen(nl, &n4)
		nl = &n4
	}

	if nr.Ullman >= gc.UINF {
		var n5 gc.Node
		gc.Tempname(&n5, nr.Type)
		gc.Cgen(nr, &n5)
		nr = &n5
	}

	rcx := int(reg[x86.REG_CX])
	var n1 gc.Node
	gc.Nodreg(&n1, gc.Types[gc.TUINT32], x86.REG_CX)

	// Allow either uint32 or uint64 as shift type,
	// to avoid unnecessary conversion from uint32 to uint64
	// just to do the comparison.
	tcount := gc.Types[gc.Simtype[nr.Type.Etype]]

	if tcount.Etype < gc.TUINT32 {
		tcount = gc.Types[gc.TUINT32]
	}

	gc.Regalloc(&n1, nr.Type, &n1) // to hold the shift type in CX
	var n3 gc.Node
	gc.Regalloc(&n3, tcount, &n1) // to clear high bits of CX

	var cx gc.Node
	gc.Nodreg(&cx, gc.Types[gc.TUINT64], x86.REG_CX)

	var oldcx gc.Node
	if rcx > 0 && !gc.Samereg(&cx, res) {
		gc.Regalloc(&oldcx, gc.Types[gc.TUINT64], nil)
		gmove(&cx, &oldcx)
	}

	cx.Type = tcount

	var n2 gc.Node
	if gc.Samereg(&cx, res) {
		gc.Regalloc(&n2, nl.Type, nil)
	} else {
		gc.Regalloc(&n2, nl.Type, res)
	}
	if nl.Ullman >= nr.Ullman {
		gc.Cgen(nl, &n2)
		gc.Cgen(nr, &n1)
		gmove(&n1, &n3)
	} else {
		gc.Cgen(nr, &n1)
		gmove(&n1, &n3)
		gc.Cgen(nl, &n2)
	}

	gc.Regfree(&n3)

	// test and fix up large shifts
	if !bounded {
		gc.Nodconst(&n3, tcount, nl.Type.Width*8)
		gins(optoas(gc.OCMP, tcount), &n1, &n3)
		p1 := gc.Gbranch(optoas(gc.OLT, tcount), nil, +1)
		if op == gc.ORSH && gc.Issigned[nl.Type.Etype] {
			gc.Nodconst(&n3, gc.Types[gc.TUINT32], nl.Type.Width*8-1)
			gins(a, &n3, &n2)
		} else {
			gc.Nodconst(&n3, nl.Type, 0)
			gmove(&n3, &n2)
		}

		gc.Patch(p1, gc.Pc)
	}

	gins(a, &n1, &n2)

	if oldcx.Op != 0 {
		cx.Type = gc.Types[gc.TUINT64]
		gmove(&oldcx, &cx)
		gc.Regfree(&oldcx)
	}

	gmove(&n2, res)

	gc.Regfree(&n1)
	gc.Regfree(&n2)
}
コード例 #25
0
ファイル: ggen.go プロジェクト: xslonepiece/goios
/*
 * generate division.
 * generates one of:
 *	res = nl / nr
 *	res = nl % nr
 * according to op.
 */
func dodiv(op int, 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 := 0
	if gc.Issigned[t.Etype] {
		check = 1
		if gc.Isconst(nl, gc.CTINT) && gc.Mpgetfix(nl.Val.U.Xval) != -(1<<uint64(t.Width*8-1)) {
			check = 0
		} else if gc.Isconst(nr, gc.CTINT) && gc.Mpgetfix(nr.Val.U.Xval) != -1 {
			check = 0
		}
	}

	if t.Width < 4 {
		if gc.Issigned[t.Etype] {
			t = gc.Types[gc.TINT32]
		} else {
			t = gc.Types[gc.TUINT32]
		}
		check = 0
	}

	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 != 0 {
		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)
		}

		p2 = gc.Gbranch(obj.AJMP, nil, 0)
		gc.Patch(p1, gc.Pc)
	}

	var olddx gc.Node
	var dx gc.Node
	savex(x86.REG_DX, &dx, &olddx, res, t)
	if !gc.Issigned[t.Etype] {
		gc.Nodconst(&n4, t, 0)
		gmove(&n4, &dx)
	} else {
		gins(optoas(gc.OEXTEND, t), nil, nil)
	}
	gins(a, &n3, nil)
	gc.Regfree(&n3)
	if op == gc.ODIV {
		gmove(&ax, res)
	} else {
		gmove(&dx, res)
	}
	restx(&dx, &olddx)
	if check != 0 {
		gc.Patch(p2, gc.Pc)
	}
	restx(&ax, &oldax)
}
コード例 #26
0
ファイル: ggen.go プロジェクト: tidatida/go
/*
 * generate division.
 * generates one of:
 *	res = nl / nr
 *	res = nl % nr
 * according to op.
 */
func dodiv(op int, 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 generate undefined result.
	// Also need to explicitly trap on division on zero,
	// the hardware will silently generate undefined result.
	// DIVW will leave unpredicable result in higher 32-bit,
	// so always use DIVD/DIVDU.
	t := nl.Type

	t0 := t
	check := 0
	if gc.Issigned[t.Etype] {
		check = 1
		if gc.Isconst(nl, gc.CTINT) && gc.Mpgetfix(nl.Val.U.Xval) != -(1<<uint64(t.Width*8-1)) {
			check = 0
		} else if gc.Isconst(nr, gc.CTINT) && gc.Mpgetfix(nr.Val.U.Xval) != -1 {
			check = 0
		}
	}

	if t.Width < 8 {
		if gc.Issigned[t.Etype] {
			t = gc.Types[gc.TINT64]
		} else {
			t = gc.Types[gc.TUINT64]
		}
		check = 0
	}

	a := optoas(gc.ODIV, t)

	var tl gc.Node
	gc.Regalloc(&tl, t0, nil)
	var tr gc.Node
	gc.Regalloc(&tr, t0, nil)
	if nl.Ullman >= nr.Ullman {
		gc.Cgen(nl, &tl)
		gc.Cgen(nr, &tr)
	} else {
		gc.Cgen(nr, &tr)
		gc.Cgen(nl, &tl)
	}

	if t != t0 {
		// Convert
		tl2 := tl

		tr2 := tr
		tl.Type = t
		tr.Type = t
		gmove(&tl2, &tl)
		gmove(&tr2, &tr)
	}

	// Handle divide-by-zero panic.
	p1 := gins(optoas(gc.OCMP, t), &tr, nil)

	p1.To.Type = obj.TYPE_REG
	p1.To.Reg = ppc64.REGZERO
	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 != 0 {
		var nm1 gc.Node
		gc.Nodconst(&nm1, t, -1)
		gins(optoas(gc.OCMP, t), &tr, &nm1)
		p1 := gc.Gbranch(optoas(gc.ONE, t), nil, +1)
		if op == gc.ODIV {
			// a / (-1) is -a.
			gins(optoas(gc.OMINUS, t), nil, &tl)

			gmove(&tl, res)
		} else {
			// a % (-1) is 0.
			var nz gc.Node
			gc.Nodconst(&nz, t, 0)

			gmove(&nz, res)
		}

		p2 = gc.Gbranch(obj.AJMP, nil, 0)
		gc.Patch(p1, gc.Pc)
	}

	p1 = gins(a, &tr, &tl)
	if op == gc.ODIV {
		gc.Regfree(&tr)
		gmove(&tl, res)
	} else {
		// A%B = A-(A/B*B)
		var tm gc.Node
		gc.Regalloc(&tm, t, nil)

		// patch div to use the 3 register form
		// TODO(minux): add gins3?
		p1.Reg = p1.To.Reg

		p1.To.Reg = tm.Val.U.Reg
		gins(optoas(gc.OMUL, t), &tr, &tm)
		gc.Regfree(&tr)
		gins(optoas(gc.OSUB, t), &tm, &tl)
		gc.Regfree(&tm)
		gmove(&tl, res)
	}

	gc.Regfree(&tl)
	if check != 0 {
		gc.Patch(p2, gc.Pc)
	}
}
コード例 #27
0
ファイル: ggen.go プロジェクト: xslonepiece/goios
func clearfat(nl *gc.Node) {
	/* clear a fat object */
	if gc.Debug['g'] != 0 {
		gc.Dump("\nclearfat", nl)
	}

	w := nl.Type.Width

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

	c := w % 8 // bytes
	q := w / 8 // quads

	if q < 4 {
		// 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.
		// NOTE: Must use agen, not igen, so that optimizer sees address
		// being taken. We are not writing on field boundaries.
		var n1 gc.Node
		gc.Agenr(nl, &n1, nil)

		n1.Op = gc.OINDREG
		var z gc.Node
		gc.Nodconst(&z, gc.Types[gc.TUINT64], 0)
		for {
			tmp14 := q
			q--
			if tmp14 <= 0 {
				break
			}
			n1.Type = z.Type
			gins(x86.AMOVQ, &z, &n1)
			n1.Xoffset += 8
		}

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

		gc.Nodconst(&z, gc.Types[gc.TUINT8], 0)
		for {
			tmp15 := c
			c--
			if tmp15 <= 0 {
				break
			}
			n1.Type = z.Type
			gins(x86.AMOVB, &z, &n1)
			n1.Xoffset++
		}

		gc.Regfree(&n1)
		return
	}

	var oldn1 gc.Node
	var n1 gc.Node
	savex(x86.REG_DI, &n1, &oldn1, nil, gc.Types[gc.Tptr])
	gc.Agen(nl, &n1)

	var ax gc.Node
	var oldax gc.Node
	savex(x86.REG_AX, &ax, &oldax, nil, gc.Types[gc.Tptr])
	gconreg(x86.AMOVL, 0, x86.REG_AX)

	if q > 128 || gc.Nacl {
		gconreg(movptr, q, x86.REG_CX)
		gins(x86.AREP, nil, nil)   // repeat
		gins(x86.ASTOSQ, nil, nil) // STOQ AL,*(DI)+
	} else {
		if di := dzDI(q); di != 0 {
			gconreg(addptr, di, x86.REG_DI)
		}
		p := gins(obj.ADUFFZERO, nil, nil)
		p.To.Type = obj.TYPE_ADDR
		p.To.Sym = gc.Linksym(gc.Pkglookup("duffzero", gc.Runtimepkg))
		p.To.Offset = dzOff(q)
	}

	z := ax
	di := n1
	if w >= 8 && c >= 4 {
		di.Op = gc.OINDREG
		z.Type = gc.Types[gc.TINT64]
		di.Type = z.Type
		p := gins(x86.AMOVQ, &z, &di)
		p.To.Scale = 1
		p.To.Offset = c - 8
	} else if c >= 4 {
		di.Op = gc.OINDREG
		z.Type = gc.Types[gc.TINT32]
		di.Type = z.Type
		gins(x86.AMOVL, &z, &di)
		if c > 4 {
			p := gins(x86.AMOVL, &z, &di)
			p.To.Scale = 1
			p.To.Offset = c - 4
		}
	} else {
		for c > 0 {
			gins(x86.ASTOSB, nil, nil) // STOB AL,*(DI)+
			c--
		}
	}

	restx(&n1, &oldn1)
	restx(&ax, &oldax)
}
コード例 #28
0
ファイル: cgen.go プロジェクト: klueska/go-akaros
/*
 * generate:
 *	if(n == true) goto to;
 */
func bgen(n *gc.Node, true_ bool, likely int, to *obj.Prog) {
	if gc.Debug['g'] != 0 {
		gc.Dump("\nbgen", n)
	}

	if n == nil {
		n = gc.Nodbool(true)
	}

	if n.Ninit != nil {
		gc.Genlist(n.Ninit)
	}

	if n.Type == nil {
		gc.Convlit(&n, gc.Types[gc.TBOOL])
		if n.Type == nil {
			return
		}
	}

	et := int(n.Type.Etype)
	if et != gc.TBOOL {
		gc.Yyerror("cgen: bad type %v for %v", gc.Tconv(n.Type, 0), gc.Oconv(int(n.Op), 0))
		gc.Patch(gins(obj.AEND, nil, nil), to)
		return
	}

	var nr *gc.Node

	for n.Op == gc.OCONVNOP {
		n = n.Left
		if n.Ninit != nil {
			gc.Genlist(n.Ninit)
		}
	}

	var nl *gc.Node
	switch n.Op {
	default:
		var n1 gc.Node
		regalloc(&n1, n.Type, nil)
		cgen(n, &n1)
		var n2 gc.Node
		gc.Nodconst(&n2, n.Type, 0)
		gins(optoas(gc.OCMP, n.Type), &n1, &n2)
		a := ppc64.ABNE
		if !true_ {
			a = ppc64.ABEQ
		}
		gc.Patch(gc.Gbranch(a, n.Type, likely), to)
		regfree(&n1)
		return

		// need to ask if it is bool?
	case gc.OLITERAL:
		if !true_ == (n.Val.U.Bval == 0) {
			gc.Patch(gc.Gbranch(ppc64.ABR, nil, likely), to)
		}
		return

	case gc.OANDAND,
		gc.OOROR:
		if (n.Op == gc.OANDAND) == true_ {
			p1 := gc.Gbranch(obj.AJMP, nil, 0)
			p2 := gc.Gbranch(obj.AJMP, nil, 0)
			gc.Patch(p1, gc.Pc)
			bgen(n.Left, !true_, -likely, p2)
			bgen(n.Right, !true_, -likely, p2)
			p1 = gc.Gbranch(obj.AJMP, nil, 0)
			gc.Patch(p1, to)
			gc.Patch(p2, gc.Pc)
		} else {
			bgen(n.Left, true_, likely, to)
			bgen(n.Right, true_, likely, to)
		}

		return

	case gc.OEQ,
		gc.ONE,
		gc.OLT,
		gc.OGT,
		gc.OLE,
		gc.OGE:
		nr = n.Right
		if nr == nil || nr.Type == nil {
			return
		}
		fallthrough

	case gc.ONOT: // unary
		nl = n.Left

		if nl == nil || nl.Type == nil {
			return
		}
	}

	switch n.Op {
	case gc.ONOT:
		bgen(nl, !true_, likely, to)
		return

	case gc.OEQ,
		gc.ONE,
		gc.OLT,
		gc.OGT,
		gc.OLE,
		gc.OGE:
		a := int(n.Op)
		if !true_ {
			if gc.Isfloat[nr.Type.Etype] {
				// brcom is not valid on floats when NaN is involved.
				p1 := gc.Gbranch(ppc64.ABR, nil, 0)

				p2 := gc.Gbranch(ppc64.ABR, nil, 0)
				gc.Patch(p1, gc.Pc)
				ll := n.Ninit // avoid re-genning ninit
				n.Ninit = nil
				bgen(n, true, -likely, p2)
				n.Ninit = ll
				gc.Patch(gc.Gbranch(ppc64.ABR, nil, 0), to)
				gc.Patch(p2, gc.Pc)
				return
			}

			a = gc.Brcom(a)
			true_ = !true_
		}

		// make simplest on right
		if nl.Op == gc.OLITERAL || (nl.Ullman < nr.Ullman && nl.Ullman < gc.UINF) {
			a = gc.Brrev(a)
			r := nl
			nl = nr
			nr = r
		}

		if gc.Isslice(nl.Type) {
			// front end should only leave cmp to literal nil
			if (a != gc.OEQ && a != gc.ONE) || nr.Op != gc.OLITERAL {
				gc.Yyerror("illegal slice comparison")
				break
			}

			a = optoas(a, gc.Types[gc.Tptr])
			var n1 gc.Node
			igen(nl, &n1, nil)
			n1.Xoffset += int64(gc.Array_array)
			n1.Type = gc.Types[gc.Tptr]
			var tmp gc.Node
			gc.Nodconst(&tmp, gc.Types[gc.Tptr], 0)
			var n2 gc.Node
			regalloc(&n2, gc.Types[gc.Tptr], &n1)
			gmove(&n1, &n2)
			gins(optoas(gc.OCMP, gc.Types[gc.Tptr]), &n2, &tmp)
			regfree(&n2)
			gc.Patch(gc.Gbranch(a, gc.Types[gc.Tptr], likely), to)
			regfree(&n1)
			break
		}

		if gc.Isinter(nl.Type) {
			// front end should only leave cmp to literal nil
			if (a != gc.OEQ && a != gc.ONE) || nr.Op != gc.OLITERAL {
				gc.Yyerror("illegal interface comparison")
				break
			}

			a = optoas(a, gc.Types[gc.Tptr])
			var n1 gc.Node
			igen(nl, &n1, nil)
			n1.Type = gc.Types[gc.Tptr]
			var tmp gc.Node
			gc.Nodconst(&tmp, gc.Types[gc.Tptr], 0)
			var n2 gc.Node
			regalloc(&n2, gc.Types[gc.Tptr], &n1)
			gmove(&n1, &n2)
			gins(optoas(gc.OCMP, gc.Types[gc.Tptr]), &n2, &tmp)
			regfree(&n2)
			gc.Patch(gc.Gbranch(a, gc.Types[gc.Tptr], likely), to)
			regfree(&n1)
			break
		}

		if gc.Iscomplex[nl.Type.Etype] {
			gc.Complexbool(a, nl, nr, true_, likely, to)
			break
		}

		var n1 gc.Node
		var n2 gc.Node
		if nr.Ullman >= gc.UINF {
			regalloc(&n1, nl.Type, nil)
			cgen(nl, &n1)

			var tmp gc.Node
			gc.Tempname(&tmp, nl.Type)
			gmove(&n1, &tmp)
			regfree(&n1)

			regalloc(&n2, nr.Type, nil)
			cgen(nr, &n2)

			regalloc(&n1, nl.Type, nil)
			cgen(&tmp, &n1)

			goto cmp
		}

		regalloc(&n1, nl.Type, nil)
		cgen(nl, &n1)

		// TODO(minux): cmpi does accept 16-bit signed immediate as p->to.
		// and cmpli accepts 16-bit unsigned immediate.
		//if(smallintconst(nr)) {
		//	gins(optoas(OCMP, nr->type), &n1, nr);
		//	patch(gbranch(optoas(a, nr->type), nr->type, likely), to);
		//	regfree(&n1);
		//	break;
		//}

		regalloc(&n2, nr.Type, nil)

		cgen(nr, &n2)

	cmp:
		l := &n1
		r := &n2
		gins(optoas(gc.OCMP, nr.Type), l, r)
		if gc.Isfloat[nr.Type.Etype] && (a == gc.OLE || a == gc.OGE) {
			// To get NaN right, must rewrite x <= y into separate x < y or x = y.
			switch a {
			case gc.OLE:
				a = gc.OLT

			case gc.OGE:
				a = gc.OGT
			}

			gc.Patch(gc.Gbranch(optoas(a, nr.Type), nr.Type, likely), to)
			gc.Patch(gc.Gbranch(optoas(gc.OEQ, nr.Type), nr.Type, likely), to)
		} else {
			gc.Patch(gc.Gbranch(optoas(a, nr.Type), nr.Type, likely), to)
		}

		regfree(&n1)
		regfree(&n2)
	}

	return
}
コード例 #29
0
ファイル: ggen.go プロジェクト: tidatida/go
/*
 * generate division.
 * caller must set:
 *	ax = allocated AX register
 *	dx = allocated DX register
 * generates one of:
 *	res = nl / nr
 *	res = nl % nr
 * according to op.
 */
func dodiv(op int, nl *gc.Node, nr *gc.Node, res *gc.Node, ax *gc.Node, dx *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 := 0
	if gc.Issigned[t.Etype] {
		check = 1
		if gc.Isconst(nl, gc.CTINT) && gc.Mpgetfix(nl.Val.U.Xval) != -1<<uint64(t.Width*8-1) {
			check = 0
		} else if gc.Isconst(nr, gc.CTINT) && gc.Mpgetfix(nr.Val.U.Xval) != -1 {
			check = 0
		}
	}

	if t.Width < 4 {
		if gc.Issigned[t.Etype] {
			t = gc.Types[gc.TINT32]
		} else {
			t = gc.Types[gc.TUINT32]
		}
		check = 0
	}

	var t1 gc.Node
	gc.Tempname(&t1, t)
	var t2 gc.Node
	gc.Tempname(&t2, t)
	if t0 != t {
		var t3 gc.Node
		gc.Tempname(&t3, t0)
		var t4 gc.Node
		gc.Tempname(&t4, t0)
		gc.Cgen(nl, &t3)
		gc.Cgen(nr, &t4)

		// Convert.
		gmove(&t3, &t1)

		gmove(&t4, &t2)
	} else {
		gc.Cgen(nl, &t1)
		gc.Cgen(nr, &t2)
	}

	var n1 gc.Node
	if !gc.Samereg(ax, res) && !gc.Samereg(dx, res) {
		gc.Regalloc(&n1, t, res)
	} else {
		gc.Regalloc(&n1, t, nil)
	}
	gmove(&t2, &n1)
	gmove(&t1, ax)
	var p2 *obj.Prog
	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), &n1, &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)
	}

	if check != 0 {
		gc.Nodconst(&n4, t, -1)
		gins(optoas(gc.OCMP, t), &n1, &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)
		}

		p2 = gc.Gbranch(obj.AJMP, nil, 0)
		gc.Patch(p1, gc.Pc)
	}

	if !gc.Issigned[t.Etype] {
		var nz gc.Node
		gc.Nodconst(&nz, t, 0)
		gmove(&nz, dx)
	} else {
		gins(optoas(gc.OEXTEND, t), nil, nil)
	}
	gins(optoas(op, t), &n1, nil)
	gc.Regfree(&n1)

	if op == gc.ODIV {
		gmove(ax, res)
	} else {
		gmove(dx, res)
	}
	if check != 0 {
		gc.Patch(p2, gc.Pc)
	}
}
コード例 #30
0
ファイル: cgen.go プロジェクト: klueska/go-akaros
/*
 * copy a composite value by moving its individual components.
 * Slices, strings and interfaces are supported.
 * Small structs or arrays with elements of basic type are
 * also supported.
 * nr is N when assigning a zero value.
 * return 1 if can do, 0 if can't.
 */
func componentgen(nr *gc.Node, nl *gc.Node) bool {
	var nodl gc.Node
	var nodr gc.Node

	freel := 0
	freer := 0

	switch nl.Type.Etype {
	default:
		goto no

	case gc.TARRAY:
		t := nl.Type

		// Slices are ok.
		if gc.Isslice(t) {
			break
		}

		// Small arrays are ok.
		if t.Bound > 0 && t.Bound <= 3 && !gc.Isfat(t.Type) {
			break
		}

		goto no

		// Small structs with non-fat types are ok.
	// Zero-sized structs are treated separately elsewhere.
	case gc.TSTRUCT:
		fldcount := int64(0)

		for t := nl.Type.Type; t != nil; t = t.Down {
			if gc.Isfat(t.Type) {
				goto no
			}
			if t.Etype != gc.TFIELD {
				gc.Fatal("componentgen: not a TFIELD: %v", gc.Tconv(t, obj.FmtLong))
			}
			fldcount++
		}

		if fldcount == 0 || fldcount > 4 {
			goto no
		}

	case gc.TSTRING,
		gc.TINTER:
		break
	}

	nodl = *nl
	if !cadable(nl) {
		if nr != nil && !cadable(nr) {
			goto no
		}
		igen(nl, &nodl, nil)
		freel = 1
	}

	if nr != nil {
		nodr = *nr
		if !cadable(nr) {
			igen(nr, &nodr, nil)
			freer = 1
		}
	} else {
		// When zeroing, prepare a register containing zero.
		var tmp gc.Node
		gc.Nodconst(&tmp, nl.Type, 0)

		regalloc(&nodr, gc.Types[gc.TUINT], nil)
		gmove(&tmp, &nodr)
		freer = 1
	}

	// nl and nr are 'cadable' which basically means they are names (variables) now.
	// If they are the same variable, don't generate any code, because the
	// VARDEF we generate will mark the old value as dead incorrectly.
	// (And also the assignments are useless.)
	if nr != nil && nl.Op == gc.ONAME && nr.Op == gc.ONAME && nl == nr {
		goto yes
	}

	switch nl.Type.Etype {
	// componentgen for arrays.
	case gc.TARRAY:
		if nl.Op == gc.ONAME {
			gc.Gvardef(nl)
		}
		t := nl.Type
		if !gc.Isslice(t) {
			nodl.Type = t.Type
			nodr.Type = nodl.Type
			for fldcount := int64(0); fldcount < t.Bound; fldcount++ {
				if nr == nil {
					gc.Clearslim(&nodl)
				} else {
					gmove(&nodr, &nodl)
				}
				nodl.Xoffset += t.Type.Width
				nodr.Xoffset += t.Type.Width
			}

			goto yes
		}

		// componentgen for slices.
		nodl.Xoffset += int64(gc.Array_array)

		nodl.Type = gc.Ptrto(nl.Type.Type)

		if nr != nil {
			nodr.Xoffset += int64(gc.Array_array)
			nodr.Type = nodl.Type
		}

		gmove(&nodr, &nodl)

		nodl.Xoffset += int64(gc.Array_nel) - int64(gc.Array_array)
		nodl.Type = gc.Types[gc.Simtype[gc.TUINT]]

		if nr != nil {
			nodr.Xoffset += int64(gc.Array_nel) - int64(gc.Array_array)
			nodr.Type = nodl.Type
		}

		gmove(&nodr, &nodl)

		nodl.Xoffset += int64(gc.Array_cap) - int64(gc.Array_nel)
		nodl.Type = gc.Types[gc.Simtype[gc.TUINT]]

		if nr != nil {
			nodr.Xoffset += int64(gc.Array_cap) - int64(gc.Array_nel)
			nodr.Type = nodl.Type
		}

		gmove(&nodr, &nodl)

		goto yes

	case gc.TSTRING:
		if nl.Op == gc.ONAME {
			gc.Gvardef(nl)
		}
		nodl.Xoffset += int64(gc.Array_array)
		nodl.Type = gc.Ptrto(gc.Types[gc.TUINT8])

		if nr != nil {
			nodr.Xoffset += int64(gc.Array_array)
			nodr.Type = nodl.Type
		}

		gmove(&nodr, &nodl)

		nodl.Xoffset += int64(gc.Array_nel) - int64(gc.Array_array)
		nodl.Type = gc.Types[gc.Simtype[gc.TUINT]]

		if nr != nil {
			nodr.Xoffset += int64(gc.Array_nel) - int64(gc.Array_array)
			nodr.Type = nodl.Type
		}

		gmove(&nodr, &nodl)

		goto yes

	case gc.TINTER:
		if nl.Op == gc.ONAME {
			gc.Gvardef(nl)
		}
		nodl.Xoffset += int64(gc.Array_array)
		nodl.Type = gc.Ptrto(gc.Types[gc.TUINT8])

		if nr != nil {
			nodr.Xoffset += int64(gc.Array_array)
			nodr.Type = nodl.Type
		}

		gmove(&nodr, &nodl)

		nodl.Xoffset += int64(gc.Array_nel) - int64(gc.Array_array)
		nodl.Type = gc.Ptrto(gc.Types[gc.TUINT8])

		if nr != nil {
			nodr.Xoffset += int64(gc.Array_nel) - int64(gc.Array_array)
			nodr.Type = nodl.Type
		}

		gmove(&nodr, &nodl)

		goto yes

	case gc.TSTRUCT:
		if nl.Op == gc.ONAME {
			gc.Gvardef(nl)
		}
		loffset := nodl.Xoffset
		roffset := nodr.Xoffset

		// funarg structs may not begin at offset zero.
		if nl.Type.Etype == gc.TSTRUCT && nl.Type.Funarg != 0 && nl.Type.Type != nil {
			loffset -= nl.Type.Type.Width
		}
		if nr != nil && nr.Type.Etype == gc.TSTRUCT && nr.Type.Funarg != 0 && nr.Type.Type != nil {
			roffset -= nr.Type.Type.Width
		}

		for t := nl.Type.Type; t != nil; t = t.Down {
			nodl.Xoffset = loffset + t.Width
			nodl.Type = t.Type

			if nr == nil {
				gc.Clearslim(&nodl)
			} else {
				nodr.Xoffset = roffset + t.Width
				nodr.Type = nodl.Type
				gmove(&nodr, &nodl)
			}
		}

		goto yes
	}

no:
	if freer != 0 {
		regfree(&nodr)
	}
	if freel != 0 {
		regfree(&nodl)
	}
	return false

yes:
	if freer != 0 {
		regfree(&nodr)
	}
	if freel != 0 {
		regfree(&nodl)
	}
	return true
}