Golang cmd-internal-obj.Aconv类(方法)实例源码

下面列出了Golang cmd-internal-obj.Aconv 类(方法)源码代码实例,从而了解它的用法。

作者:duhaibo040    项目:go-   
// as2variant returns the variant (V_*) flags of instruction as.
func as2variant(as obj.As) int {
	for i, v := range varianttable[as&obj.AMask] {
		if v&obj.AMask == as&obj.AMask {
			return i
		}
	}
	gc.Fatalf("as2variant: instruction %v is not a variant of itself", obj.Aconv(as&obj.AMask))
	return 0
}

作者:danny800    项目:g   
func oplook(ctxt *obj.Link, p *obj.Prog) *Optab {
	if oprange[AOR&obj.AMask].start == nil {
		buildop(ctxt)
	}

	a1 := int(p.Optab)
	if a1 != 0 {
		return &optab[a1-1:][0]
	}
	a1 = int(p.From.Class)
	if a1 == 0 {
		a1 = aclass(ctxt, &p.From) + 1
		p.From.Class = int8(a1)
	}

	a1--
	a3 := int(p.To.Class)
	if a3 == 0 {
		a3 = aclass(ctxt, &p.To) + 1
		p.To.Class = int8(a3)
	}

	a3--
	a2 := C_NONE
	if p.Reg != 0 {
		a2 = C_REG
	}

	//print("oplook %P %d %d %d\n", p, a1, a2, a3);
	r0 := p.As & obj.AMask

	o := oprange[r0].start
	if o == nil {
		o = oprange[r0].stop /* just generate an error */
	}
	e := oprange[r0].stop
	c1 := xcmp[a1][:]
	c3 := xcmp[a3][:]
	for ; -cap(o) < -cap(e); o = o[1:] {
		if int(o[0].a2) == a2 {
			if c1[o[0].a1] != 0 {
				if c3[o[0].a3] != 0 {
					p.Optab = uint16((-cap(o) + cap(optab)) + 1)
					return &o[0]
				}
			}
		}
	}

	ctxt.Diag("illegal combination %v %v %v %v", obj.Aconv(int(p.As)), DRconv(a1), DRconv(a2), DRconv(a3))
	prasm(p)
	if o == nil {
		o = optab
	}
	return &o[0]
}

作者:ckeye    项目:gosr   
// as2variant returns the variant (V_*) flags of instruction as.
func as2variant(as int) int {
	initvariants()
	for i := int(0); i < len(varianttable[as]); i++ {
		if varianttable[as][i] == as {
			return i
		}
	}
	gc.Fatalf("as2variant: instruction %v is not a variant of itself", obj.Aconv(as))
	return 0
}

作者:2theto    项目:g   
func oplook(ctxt *obj.Link, p *obj.Prog) *Optab {
	if oprange[AOR&obj.AMask] == nil {
		buildop(ctxt)
	}

	a1 := int(p.Optab)
	if a1 != 0 {
		return &optab[a1-1]
	}
	a1 = int(p.From.Class)
	if a1 == 0 {
		a1 = aclass(ctxt, &p.From) + 1
		p.From.Class = int8(a1)
	}

	a1--
	a3 := int(p.To.Class)
	if a3 == 0 {
		a3 = aclass(ctxt, &p.To) + 1
		p.To.Class = int8(a3)
	}

	a3--
	a2 := C_NONE
	if p.Reg != 0 {
		a2 = C_REG
	}

	//print("oplook %P %d %d %d\n", p, a1, a2, a3);

	ops := oprange[p.As&obj.AMask]
	c1 := &xcmp[a1]
	c3 := &xcmp[a3]
	for i := range ops {
		op := &ops[i]
		if int(op.a2) == a2 && c1[op.a1] && c3[op.a3] {
			p.Optab = uint16(cap(optab) - cap(ops) + i + 1)
			return op
		}
	}

	ctxt.Diag("illegal combination %v %v %v %v", obj.Aconv(p.As), DRconv(a1), DRconv(a2), DRconv(a3))
	prasm(p)
	if ops == nil {
		ops = optab
	}
	return &ops[0]
}

作者:xiezerozer    项目:g   
/*
 * shortprop eliminates redundant zero/sign extensions.
 *
 *   MOVBS x, R
 *   <no use R>
 *   MOVBS R, R'
 *
 * changed to
 *
 *   MOVBS x, R
 *   ...
 *   MOVB  R, R' (compiled to mov)
 *
 * MOVBS above can be a MOVBS, MOVBU, MOVHS or MOVHU.
 */
func shortprop(r *gc.Flow) bool {
	p := (*obj.Prog)(r.Prog)
	r1 := (*gc.Flow)(findpre(r, &p.From))
	if r1 == nil {
		return false
	}

	p1 := (*obj.Prog)(r1.Prog)
	if p1.As == p.As {
		// Two consecutive extensions.
		goto gotit
	}

	if p1.As == arm.AMOVW && isdconst(&p1.From) && p1.From.Offset >= 0 && p1.From.Offset < 128 {
		// Loaded an immediate.
		goto gotit
	}

	return false

gotit:
	if gc.Debug['P'] != 0 {
		fmt.Printf("shortprop\n%v\n%v", p1, p)
	}
	switch p.As {
	case arm.AMOVBS,
		arm.AMOVBU:
		p.As = arm.AMOVB

	case arm.AMOVHS,
		arm.AMOVHU:
		p.As = arm.AMOVH
	}

	if gc.Debug['P'] != 0 {
		fmt.Printf(" => %v\n", obj.Aconv(int(p.As)))
	}
	return true
}

作者:duhaibo040    项目:go-   
//.........这里部分代码省略.........
		return AJNE
	case AJNE:
		return AJEQ
	case AJLE:
		return AJGT
	case AJLS:
		return AJHI
	case AJLT:
		return AJGE
	case AJMI:
		return AJPL
	case AJGE:
		return AJLT
	case AJPL:
		return AJMI
	case AJGT:
		return AJLE
	case AJHI:
		return AJLS
	case AJCS:
		return AJCC
	case AJCC:
		return AJCS
	case AJPS:
		return AJPC
	case AJPC:
		return AJPS
	case AJOS:
		return AJOC
	case AJOC:
		return AJOS
	}

	log.Fatalf("unknown relation: %s", obj.Aconv(a))
	return 0
}

func xfol(ctxt *obj.Link, p *obj.Prog, last **obj.Prog) {
	var q *obj.Prog
	var i int
	var a obj.As

loop:
	if p == nil {
		return
	}
	if p.As == obj.AJMP {
		q = p.Pcond
		if q != nil && q.As != obj.ATEXT {
			/* mark instruction as done and continue layout at target of jump */
			p.Mark |= DONE

			p = q
			if p.Mark&DONE == 0 {
				goto loop
			}
		}
	}

	if p.Mark&DONE != 0 {
		/*
		 * p goes here, but already used it elsewhere.
		 * copy up to 4 instructions or else branch to other copy.
		 */
		i = 0
		q = p

作者:noscripte    项目:g   
// getRegister checks that addr represents a register and returns its value.
func (p *Parser) getRegister(prog *obj.Prog, op int, addr *obj.Addr) int16 {
	if addr.Type != obj.TYPE_REG || addr.Offset != 0 || addr.Name != 0 || addr.Index != 0 {
		p.errorf("%s: expected register; found %s", obj.Aconv(op), obj.Dconv(prog, addr))
	}
	return addr.Reg
}

作者:noscripte    项目:g   
// getImmediate checks that addr represents an immediate constant and returns its value.
func (p *Parser) getImmediate(prog *obj.Prog, op int, addr *obj.Addr) int64 {
	if addr.Type != obj.TYPE_CONST || addr.Name != 0 || addr.Reg != 0 || addr.Index != 0 {
		p.errorf("%s: expected immediate constant; found %s", obj.Aconv(op), obj.Dconv(prog, addr))
	}
	return addr.Offset
}

作者:noscripte    项目:g   
// asmInstruction assembles an instruction.
// MOVW R9, (R10)
func (p *Parser) asmInstruction(op int, cond string, a []obj.Addr) {
	// fmt.Printf("%s %+v\n", obj.Aconv(op), a)
	prog := &obj.Prog{
		Ctxt:   p.ctxt,
		Lineno: p.histLineNum,
		As:     int16(op),
	}
	switch len(a) {
	case 0:
		// Nothing to do.
	case 1:
		if p.arch.UnaryDst[op] {
			// prog.From is no address.
			prog.To = a[0]
		} else {
			prog.From = a[0]
			// prog.To is no address.
		}
		if p.arch.Thechar == '9' && arch.IsPPC64NEG(op) {
			// NEG: From and To are both a[0].
			prog.To = a[0]
			prog.From = a[0]
			break
		}
	case 2:
		if p.arch.Thechar == '5' {
			if arch.IsARMCMP(op) {
				prog.From = a[0]
				prog.Reg = p.getRegister(prog, op, &a[1])
				break
			}
			// Strange special cases.
			if arch.IsARMSTREX(op) {
				/*
					STREX x, (y)
						from=(y) reg=x to=x
					STREX (x), y
						from=(x) reg=y to=y
				*/
				if a[0].Type == obj.TYPE_REG && a[1].Type != obj.TYPE_REG {
					prog.From = a[1]
					prog.Reg = a[0].Reg
					prog.To = a[0]
					break
				} else if a[0].Type != obj.TYPE_REG && a[1].Type == obj.TYPE_REG {
					prog.From = a[0]
					prog.Reg = a[1].Reg
					prog.To = a[1]
					break
				}
				p.errorf("unrecognized addressing for %s", obj.Aconv(op))
				return
			}
			if arch.IsARMFloatCmp(op) {
				prog.From = a[0]
				prog.Reg = p.getRegister(prog, op, &a[1])
				break
			}
		} else if p.arch.Thechar == '7' && arch.IsARM64CMP(op) {
			prog.From = a[0]
			prog.Reg = p.getRegister(prog, op, &a[1])
			break
		}
		prog.From = a[0]
		prog.To = a[1]
	case 3:
		switch p.arch.Thechar {
		case '5':
			// Special cases.
			if arch.IsARMSTREX(op) {
				/*
					STREX x, (y), z
						from=(y) reg=x to=z
				*/
				prog.From = a[1]
				prog.Reg = p.getRegister(prog, op, &a[0])
				prog.To = a[2]
				break
			}
			// Otherwise the 2nd operand (a[1]) must be a register.
			prog.From = a[0]
			prog.Reg = p.getRegister(prog, op, &a[1])
			prog.To = a[2]
		case '7':
			// ARM64 instructions with one input and two outputs.
			if arch.IsARM64STLXR(op) {
				prog.From = a[0]
				prog.To = a[1]
				if a[2].Type != obj.TYPE_REG {
					p.errorf("invalid addressing modes for third operand to %s instruction, must be register", obj.Aconv(op))
					return
				}
				prog.RegTo2 = a[2].Reg
				break
			}
			prog.From = a[0]
			prog.Reg = p.getRegister(prog, op, &a[1])
			prog.To = a[2]
//.........这里部分代码省略.........

作者:noscripte    项目:g   
// asmJump assembles a jump instruction.
// JMP	R1
// JMP	exit
// JMP	3(PC)
func (p *Parser) asmJump(op int, cond string, a []obj.Addr) {
	var target *obj.Addr
	prog := &obj.Prog{
		Ctxt:   p.ctxt,
		Lineno: p.histLineNum,
		As:     int16(op),
	}
	switch len(a) {
	case 1:
		target = &a[0]
	case 2:
		// Special 2-operand jumps.
		target = &a[1]
		prog.From = a[0]
	case 3:
		if p.arch.Thechar == '9' {
			// Special 3-operand jumps.
			// First two must be constants; a[1] is a register number.
			target = &a[2]
			prog.From = obj.Addr{
				Type:   obj.TYPE_CONST,
				Offset: p.getConstant(prog, op, &a[0]),
			}
			reg := int16(p.getConstant(prog, op, &a[1]))
			reg, ok := p.arch.RegisterNumber("R", int16(reg))
			if !ok {
				p.errorf("bad register number %d", reg)
				return
			}
			prog.Reg = reg
			break
		}
		fallthrough
	default:
		p.errorf("wrong number of arguments to %s instruction", obj.Aconv(op))
		return
	}
	switch {
	case target.Type == obj.TYPE_BRANCH:
		// JMP 4(PC)
		prog.To = obj.Addr{
			Type:   obj.TYPE_BRANCH,
			Offset: p.pc + 1 + target.Offset, // +1 because p.pc is incremented in append, below.
		}
	case target.Type == obj.TYPE_REG:
		// JMP R1
		prog.To = *target
	case target.Type == obj.TYPE_MEM && (target.Name == obj.NAME_EXTERN || target.Name == obj.NAME_STATIC):
		// JMP main·morestack(SB)
		prog.To = *target
	case target.Type == obj.TYPE_INDIR && (target.Name == obj.NAME_EXTERN || target.Name == obj.NAME_STATIC):
		// JMP *main·morestack(SB)
		prog.To = *target
		prog.To.Type = obj.TYPE_INDIR
	case target.Type == obj.TYPE_MEM && target.Reg == 0 && target.Offset == 0:
		// JMP exit
		if target.Sym == nil {
			// Parse error left name unset.
			return
		}
		targetProg := p.labels[target.Sym.Name]
		if targetProg == nil {
			p.toPatch = append(p.toPatch, Patch{prog, target.Sym.Name})
		} else {
			p.branch(prog, targetProg)
		}
	case target.Type == obj.TYPE_MEM && target.Name == obj.NAME_NONE:
		// JMP 4(R0)
		prog.To = *target
		// On the ppc64, 9a encodes BR (CTR) as BR CTR. We do the same.
		if p.arch.Thechar == '9' && target.Offset == 0 {
			prog.To.Type = obj.TYPE_REG
		}
	case target.Type == obj.TYPE_CONST:
		// JMP $4
		prog.To = a[0]
	default:
		p.errorf("cannot assemble jump %+v", target)
		return
	}

	p.append(prog, cond, true)
}

作者:duhaibo040    项目:go-   
// getConstant checks that addr represents a plain constant and returns its value.
func (p *Parser) getConstant(prog *obj.Prog, op obj.As, addr *obj.Addr) int64 {
	if addr.Type != obj.TYPE_MEM || addr.Name != 0 || addr.Reg != 0 || addr.Index != 0 {
		p.errorf("%s: expected integer constant; found %s", obj.Aconv(op), obj.Dconv(prog, addr))
	}
	return addr.Offset
}

作者:wycharr    项目:g   
// If s==nil, copyu returns the set/use of v in p; otherwise, it
// modifies p to replace reads of v with reads of s and returns 0 for
// success or non-zero for failure.
//
// If s==nil, copy returns one of the following values:
// 	1 if v only used
//	2 if v is set and used in one address (read-alter-rewrite;
// 	  can't substitute)
//	3 if v is only set
//	4 if v is set in one address and used in another (so addresses
// 	  can be rewritten independently)
//	0 otherwise (not touched)
func copyu(p *obj.Prog, v *obj.Addr, s *obj.Addr) int {
	if p.From3Type() != obj.TYPE_NONE && p.From3Type() != obj.TYPE_CONST {
		// Currently we never generate a From3 with anything other than a constant in it.
		fmt.Printf("copyu: From3 (%v) not implemented\n", gc.Ctxt.Dconv(p.From3))
	}

	switch p.As {
	default:
		fmt.Printf("copyu: can't find %v\n", obj.Aconv(int(p.As)))
		return 2

	case obj.ANOP, /* read p->from, write p->to */
		s390x.AMOVH,
		s390x.AMOVHZ,
		s390x.AMOVB,
		s390x.AMOVBZ,
		s390x.AMOVW,
		s390x.AMOVWZ,
		s390x.AMOVD,
		s390x.ANEG,
		s390x.AADDME,
		s390x.AADDZE,
		s390x.ASUBME,
		s390x.ASUBZE,
		s390x.AFMOVS,
		s390x.AFMOVD,
		s390x.AFRSP,
		s390x.AFNEG,
		s390x.ALDEBR,
		s390x.ACLFEBR,
		s390x.ACLGEBR,
		s390x.ACLFDBR,
		s390x.ACLGDBR,
		s390x.ACFEBRA,
		s390x.ACGEBRA,
		s390x.ACFDBRA,
		s390x.ACGDBRA,
		s390x.ACELFBR,
		s390x.ACELGBR,
		s390x.ACDLFBR,
		s390x.ACDLGBR,
		s390x.ACEFBRA,
		s390x.ACEGBRA,
		s390x.ACDFBRA,
		s390x.ACDGBRA,
		s390x.AFSQRT:

		if s != nil {
			if copysub(&p.From, v, s, 1) != 0 {
				return 1
			}

			// Update only indirect uses of v in p->to
			if !copyas(&p.To, v) {
				if copysub(&p.To, v, s, 1) != 0 {
					return 1
				}
			}
			return 0
		}

		if copyas(&p.To, v) {
			// Fix up implicit from
			if p.From.Type == obj.TYPE_NONE {
				p.From = p.To
			}
			if copyau(&p.From, v) {
				return 4
			}
			return 3
		}

		if copyau(&p.From, v) {
			return 1
		}
		if copyau(&p.To, v) {
			// p->to only indirectly uses v
			return 1
		}

		return 0

	// read p->from, read p->reg, rar p->to
	case s390x.ARLWMI:
		if copyas(&p.To, v) {
			return 2
		}
		fallthrough
//.........这里部分代码省略.........

作者:danny800    项目:g   
//.........这里部分代码省略.........
	case AMULVU:
		return OP(3, 5)

	case AJMP:
		return OP(1, 0)
	case AJAL:
		return OP(1, 1)

	case ABREAK:
		return OP(1, 5)
	case ASYSCALL:
		return OP(1, 4)
	case ATLBP:
		return MMU(1, 0)
	case ATLBR:
		return MMU(0, 1)
	case ATLBWI:
		return MMU(0, 2)
	case ATLBWR:
		return MMU(0, 6)
	case ARFE:
		return MMU(2, 0)

	case ADIVF:
		return FPF(0, 3)
	case ADIVD:
		return FPD(0, 3)
	case AMULF:
		return FPF(0, 2)
	case AMULD:
		return FPD(0, 2)
	case ASUBF:
		return FPF(0, 1)
	case ASUBD:
		return FPD(0, 1)
	case AADDF:
		return FPF(0, 0)
	case AADDD:
		return FPD(0, 0)
	case ATRUNCFV:
		return FPF(1, 1)
	case ATRUNCDV:
		return FPD(1, 1)
	case ATRUNCFW:
		return FPF(1, 5)
	case ATRUNCDW:
		return FPD(1, 5)
	case AMOVFV:
		return FPF(4, 5)
	case AMOVDV:
		return FPD(4, 5)
	case AMOVVF:
		return FPV(4, 0)
	case AMOVVD:
		return FPV(4, 1)
	case AMOVFW:
		return FPF(4, 4)
	case AMOVDW:
		return FPD(4, 4)
	case AMOVWF:
		return FPW(4, 0)
	case AMOVDF:
		return FPD(4, 0)
	case AMOVWD:
		return FPW(4, 1)
	case AMOVFD:
		return FPF(4, 1)
	case AABSF:
		return FPF(0, 5)
	case AABSD:
		return FPD(0, 5)
	case AMOVF:
		return FPF(0, 6)
	case AMOVD:
		return FPD(0, 6)
	case ANEGF:
		return FPF(0, 7)
	case ANEGD:
		return FPD(0, 7)
	case ACMPEQF:
		return FPF(6, 2)
	case ACMPEQD:
		return FPD(6, 2)
	case ACMPGTF:
		return FPF(7, 4)
	case ACMPGTD:
		return FPD(7, 4)
	case ACMPGEF:
		return FPF(7, 6)
	case ACMPGED:
		return FPD(7, 6)
	}

	if a >= ALAST {
		ctxt.Diag("bad rrr opcode %v+ALAST", obj.Aconv(a-ALAST))
	} else {
		ctxt.Diag("bad rrr opcode %v", obj.Aconv(a))
	}
	return 0
}

作者:ckeye    项目:gosr   
// If s==nil, copyu returns the set/use of v in p; otherwise, it
// modifies p to replace reads of v with reads of s and returns 0 for
// success or non-zero for failure.
//
// If s==nil, copy returns one of the following values:
// 	1 if v only used
//	2 if v is set and used in one address (read-alter-rewrite;
// 	  can't substitute)
//	3 if v is only set
//	4 if v is set in one address and used in another (so addresses
// 	  can be rewritten independently)
//	0 otherwise (not touched)
func copyu(p *obj.Prog, v *obj.Addr, s *obj.Addr) int {
	if p.From3Type() != obj.TYPE_NONE {
		// never generates a from3
		fmt.Printf("copyu: from3 (%v) not implemented\n", gc.Ctxt.Dconv(p.From3))
	}

	switch p.As {
	default:
		fmt.Printf("copyu: can't find %v\n", obj.Aconv(int(p.As)))
		return 2

	case obj.ANOP, /* read p->from, write p->to */
		mips.AMOVV,
		mips.AMOVF,
		mips.AMOVD,
		mips.AMOVH,
		mips.AMOVHU,
		mips.AMOVB,
		mips.AMOVBU,
		mips.AMOVW,
		mips.AMOVWU,
		mips.AMOVFD,
		mips.AMOVDF,
		mips.AMOVDW,
		mips.AMOVWD,
		mips.AMOVFW,
		mips.AMOVWF,
		mips.AMOVDV,
		mips.AMOVVD,
		mips.AMOVFV,
		mips.AMOVVF,
		mips.ATRUNCFV,
		mips.ATRUNCDV,
		mips.ATRUNCFW,
		mips.ATRUNCDW:
		if s != nil {
			if copysub(&p.From, v, s, 1) != 0 {
				return 1
			}

			// Update only indirect uses of v in p->to
			if !copyas(&p.To, v) {
				if copysub(&p.To, v, s, 1) != 0 {
					return 1
				}
			}
			return 0
		}

		if copyas(&p.To, v) {
			// Fix up implicit from
			if p.From.Type == obj.TYPE_NONE {
				p.From = p.To
			}
			if copyau(&p.From, v) {
				return 4
			}
			return 3
		}

		if copyau(&p.From, v) {
			return 1
		}
		if copyau(&p.To, v) {
			// p->to only indirectly uses v
			return 1
		}

		return 0

	case mips.ASGT, /* read p->from, read p->reg, write p->to */
		mips.ASGTU,

		mips.AADD,
		mips.AADDU,
		mips.ASUB,
		mips.ASUBU,
		mips.ASLL,
		mips.ASRL,
		mips.ASRA,
		mips.AOR,
		mips.ANOR,
		mips.AAND,
		mips.AXOR,

		mips.AADDV,
		mips.AADDVU,
		mips.ASUBV,
//.........这里部分代码省略.........

作者:xslonepiec    项目:goio   
// If s==nil, copyu returns the set/use of v in p; otherwise, it
// modifies p to replace reads of v with reads of s and returns 0 for
// success or non-zero for failure.
//
// If s==nil, copy returns one of the following values:
//	1 if v only used
//	2 if v is set and used in one address (read-alter-rewrite;
//	  can't substitute)
//	3 if v is only set
//	4 if v is set in one address and used in another (so addresses
//	  can be rewritten independently)
//	0 otherwise (not touched)
func copyu(p *obj.Prog, v *obj.Addr, s *obj.Addr) int {
	if p.From3.Type != obj.TYPE_NONE {
		// 7g never generates a from3
		fmt.Printf("copyu: from3 (%v) not implemented\n", gc.Ctxt.Dconv(&p.From3))
	}
	if p.To2.Type != obj.TYPE_NONE {
		// 7g never generates a to2
		fmt.Printf("copyu: to2 (%v) not implemented\n", gc.Ctxt.Dconv(&p.To2))
	}

	switch p.As {
	default:
		fmt.Printf("copyu: can't find %v\n", obj.Aconv(int(p.As)))
		return 2

	case obj.ANOP, /* read p->from, write p->to */
		arm64.ANEG,
		arm64.AFNEGD,
		arm64.AFNEGS,
		arm64.AFSQRTD,
		arm64.AFCVTZSD,
		arm64.AFCVTZSS,
		arm64.AFCVTZSDW,
		arm64.AFCVTZSSW,
		arm64.AFCVTZUD,
		arm64.AFCVTZUS,
		arm64.AFCVTZUDW,
		arm64.AFCVTZUSW,
		arm64.AFCVTSD,
		arm64.AFCVTDS,
		arm64.ASCVTFD,
		arm64.ASCVTFS,
		arm64.ASCVTFWD,
		arm64.ASCVTFWS,
		arm64.AUCVTFD,
		arm64.AUCVTFS,
		arm64.AUCVTFWD,
		arm64.AUCVTFWS,
		arm64.AMOVB,
		arm64.AMOVBU,
		arm64.AMOVH,
		arm64.AMOVHU,
		arm64.AMOVW,
		arm64.AMOVWU,
		arm64.AMOVD,
		arm64.AFMOVS,
		arm64.AFMOVD:
		if p.Scond == 0 {
			if s != nil {
				if copysub(&p.From, v, s, 1) != 0 {
					return 1
				}

				// Update only indirect uses of v in p->to
				if !copyas(&p.To, v) {
					if copysub(&p.To, v, s, 1) != 0 {
						return 1
					}
				}
				return 0
			}

			if copyas(&p.To, v) {
				// Fix up implicit from
				if p.From.Type == obj.TYPE_NONE {
					p.From = p.To
				}
				if copyau(&p.From, v) {
					return 4
				}
				return 3
			}

			if copyau(&p.From, v) {
				return 1
			}
			if copyau(&p.To, v) {
				// p->to only indirectly uses v
				return 1
			}

			return 0
		}

		/* rar p->from, write p->to or read p->from, rar p->to */
		if p.From.Type == obj.TYPE_MEM {
			if copyas(&p.From, v) {
				// No s!=nil check; need to fail
//.........这里部分代码省略.........

作者:duhaibo040    项目:go-   
// If s==nil, copyu returns the set/use of v in p; otherwise, it
// modifies p to replace reads of v with reads of s and returns 0 for
// success or non-zero for failure.
//
// If s==nil, copy returns one of the following values:
// 	1 if v only used
//	2 if v is set and used in one address (read-alter-rewrite;
// 	  can't substitute)
//	3 if v is only set
//	4 if v is set in one address and used in another (so addresses
// 	  can be rewritten independently)
//	0 otherwise (not touched)
func copyu(p *obj.Prog, v *obj.Addr, s *obj.Addr) int {
	if p.From3Type() != obj.TYPE_NONE {
		// 9g never generates a from3
		fmt.Printf("copyu: from3 (%v) not implemented\n", gc.Ctxt.Dconv(p.From3))
	}

	switch p.As {
	default:
		fmt.Printf("copyu: can't find %v\n", obj.Aconv(p.As))
		return 2

	case obj.ANOP, /* read p->from, write p->to */
		ppc64.AMOVH,
		ppc64.AMOVHZ,
		ppc64.AMOVB,
		ppc64.AMOVBZ,
		ppc64.AMOVW,
		ppc64.AMOVWZ,
		ppc64.AMOVD,
		ppc64.ANEG,
		ppc64.ANEGCC,
		ppc64.AADDME,
		ppc64.AADDMECC,
		ppc64.AADDZE,
		ppc64.AADDZECC,
		ppc64.ASUBME,
		ppc64.ASUBMECC,
		ppc64.ASUBZE,
		ppc64.ASUBZECC,
		ppc64.AFCTIW,
		ppc64.AFCTIWZ,
		ppc64.AFCTID,
		ppc64.AFCTIDZ,
		ppc64.AFCFID,
		ppc64.AFCFIDCC,
		ppc64.AFMOVS,
		ppc64.AFMOVD,
		ppc64.AFRSP,
		ppc64.AFNEG,
		ppc64.AFNEGCC,
		ppc64.AFSQRT:
		if s != nil {
			if copysub(&p.From, v, s, true) {
				return 1
			}

			// Update only indirect uses of v in p->to
			if !copyas(&p.To, v) {
				if copysub(&p.To, v, s, true) {
					return 1
				}
			}
			return 0
		}

		if copyas(&p.To, v) {
			// Fix up implicit from
			if p.From.Type == obj.TYPE_NONE {
				p.From = p.To
			}
			if copyau(&p.From, v) {
				return 4
			}
			return 3
		}

		if copyau(&p.From, v) {
			return 1
		}
		if copyau(&p.To, v) {
			// p->to only indirectly uses v
			return 1
		}

		return 0

	case ppc64.AMOVBU, /* rar p->from, write p->to or read p->from, rar p->to */
		ppc64.AMOVBZU,
		ppc64.AMOVHU,
		ppc64.AMOVHZU,
		ppc64.AMOVWZU,
		ppc64.AMOVDU:
		if p.From.Type == obj.TYPE_MEM {
			if copyas(&p.From, v) {
				// No s!=nil check; need to fail
				// anyway in that case
				return 2
			}
//.........这里部分代码省略.........

作者:duhaibo040    项目:go-   
//.........这里部分代码省略.........
				}
			}
		}
	}

	if t != 0 {
		goto loop1
	}

	/*
	 * look for MOVB x,R; MOVB R,R (for small MOVs not handled above)
	 */
	var p1 *obj.Prog
	var r1 *gc.Flow
	for r := g.Start; r != nil; r = r.Link {
		p = r.Prog
		switch p.As {
		default:
			continue

		case arm64.AMOVH,
			arm64.AMOVHU,
			arm64.AMOVB,
			arm64.AMOVBU,
			arm64.AMOVW,
			arm64.AMOVWU:
			if p.To.Type != obj.TYPE_REG {
				continue
			}
		}

		r1 = r.Link
		if r1 == nil {
			continue
		}
		p1 = r1.Prog
		if p1.As != p.As {
			continue
		}
		if p1.From.Type != obj.TYPE_REG || p1.From.Reg != p.To.Reg {
			continue
		}
		if p1.To.Type != obj.TYPE_REG || p1.To.Reg != p.To.Reg {
			continue
		}
		excise(r1)
	}

	if gc.Debug['D'] > 1 {
		goto ret /* allow following code improvement to be suppressed */
	}

	// MOVD $c, R'; ADD R', R (R' unused) -> ADD $c, R
	for r := g.Start; r != nil; r = r.Link {
		p = r.Prog
		switch p.As {
		default:
			continue

		case arm64.AMOVD:
			if p.To.Type != obj.TYPE_REG {
				continue
			}
			if p.From.Type != obj.TYPE_CONST {
				continue
			}
			if p.From.Offset < 0 || 4096 <= p.From.Offset {
				continue
			}
		}
		r1 = r.Link
		if r1 == nil {
			continue
		}
		p1 = r1.Prog
		if p1.As != arm64.AADD && p1.As != arm64.ASUB { // TODO(aram): also logical after we have bimm.
			continue
		}
		if p1.From.Type != obj.TYPE_REG || p1.From.Reg != p.To.Reg {
			continue
		}
		if p1.To.Type != obj.TYPE_REG {
			continue
		}
		if gc.Debug['P'] != 0 {
			fmt.Printf("encoding $%d directly into %v in:\n%v\n%v\n", p.From.Offset, obj.Aconv(p1.As), p, p1)
		}
		p1.From.Type = obj.TYPE_CONST
		p1.From = p.From
		excise(r)
	}

	/* TODO(minux):
	 * look for OP x,y,R; CMP R, $0 -> OP.S x,y,R
	 * when OP can set condition codes correctly
	 */

ret:
	gc.Flowend(g)
}

作者:danny800    项目:g   
//.........这里部分代码省略.........
	case ABGTZ:
		return SP(0, 7)
	case ABGTZ + ALAST:
		return SP(2, 7) /* likely */
	case ABLEZ:
		return SP(0, 6)
	case ABLEZ + ALAST:
		return SP(2, 6) /* likely */
	case ABLTZ:
		return SP(0, 1) | BCOND(0, 0)
	case ABLTZ + ALAST:
		return SP(0, 1) | BCOND(0, 2) /* likely */
	case ABLTZAL:
		return SP(0, 1) | BCOND(2, 0)
	case ABLTZAL + ALAST:
		return SP(0, 1) | BCOND(2, 2) /* likely */
	case ABFPT:
		return SP(2, 1) | (257 << 16)
	case ABFPT + ALAST:
		return SP(2, 1) | (259 << 16) /* likely */
	case ABFPF:
		return SP(2, 1) | (256 << 16)
	case ABFPF + ALAST:
		return SP(2, 1) | (258 << 16) /* likely */

	case AMOVB,
		AMOVBU:
		return SP(5, 0)
	case AMOVH,
		AMOVHU:
		return SP(5, 1)
	case AMOVW,
		AMOVWU:
		return SP(5, 3)
	case AMOVV:
		return SP(7, 7)
	case AMOVF:
		return SP(7, 1)
	case AMOVD:
		return SP(7, 5)
	case AMOVWL:
		return SP(5, 2)
	case AMOVWR:
		return SP(5, 6)
	case AMOVVL:
		return SP(5, 4)
	case AMOVVR:
		return SP(5, 5)

	case ABREAK:
		return SP(5, 7)

	case AMOVWL + ALAST:
		return SP(4, 2)
	case AMOVWR + ALAST:
		return SP(4, 6)
	case AMOVVL + ALAST:
		return SP(3, 2)
	case AMOVVR + ALAST:
		return SP(3, 3)
	case AMOVB + ALAST:
		return SP(4, 0)
	case AMOVBU + ALAST:
		return SP(4, 4)
	case AMOVH + ALAST:
		return SP(4, 1)
	case AMOVHU + ALAST:
		return SP(4, 5)
	case AMOVW + ALAST:
		return SP(4, 3)
	case AMOVWU + ALAST:
		return SP(4, 7)
	case AMOVV + ALAST:
		return SP(6, 7)
	case AMOVF + ALAST:
		return SP(6, 1)
	case AMOVD + ALAST:
		return SP(6, 5)

	case ASLLV:
		return OP(7, 0)
	case ASRLV:
		return OP(7, 2)
	case ASRAV:
		return OP(7, 3)
	case ASLLV + ALAST:
		return OP(7, 4)
	case ASRLV + ALAST:
		return OP(7, 6)
	case ASRAV + ALAST:
		return OP(7, 7)
	}

	if a >= ALAST {
		ctxt.Diag("bad irr opcode %v+ALAST", obj.Aconv(a-ALAST))
	} else {
		ctxt.Diag("bad irr opcode %v", obj.Aconv(a))
	}
	return 0
}

作者:xiezerozer    项目:g   
/*
 * return
 * 1 if v only used (and substitute),
 * 2 if read-alter-rewrite
 * 3 if set
 * 4 if set and used
 * 0 otherwise (not touched)
 */
func copyu(p *obj.Prog, v *obj.Addr, s *obj.Addr) int {
	switch p.As {
	default:
		fmt.Printf("copyu: can't find %v\n", obj.Aconv(int(p.As)))
		return 2

	case arm.AMOVM:
		if v.Type != obj.TYPE_REG {
			return 0
		}
		if p.From.Type == obj.TYPE_CONST { /* read reglist, read/rar */
			if s != nil {
				if p.From.Offset&(1<<uint(v.Reg)) != 0 {
					return 1
				}
				if copysub(&p.To, v, s, 1) != 0 {
					return 1
				}
				return 0
			}

			if copyau(&p.To, v) {
				if p.Scond&arm.C_WBIT != 0 {
					return 2
				}
				return 1
			}

			if p.From.Offset&(1<<uint(v.Reg)) != 0 {
				return 1 /* read/rar, write reglist */
			}
		} else {
			if s != nil {
				if p.To.Offset&(1<<uint(v.Reg)) != 0 {
					return 1
				}
				if copysub(&p.From, v, s, 1) != 0 {
					return 1
				}
				return 0
			}

			if copyau(&p.From, v) {
				if p.Scond&arm.C_WBIT != 0 {
					return 2
				}
				if p.To.Offset&(1<<uint(v.Reg)) != 0 {
					return 4
				}
				return 1
			}

			if p.To.Offset&(1<<uint(v.Reg)) != 0 {
				return 3
			}
		}

		return 0

	case obj.ANOP, /* read,, write */
		arm.ASQRTD,
		arm.AMOVW,
		arm.AMOVF,
		arm.AMOVD,
		arm.AMOVH,
		arm.AMOVHS,
		arm.AMOVHU,
		arm.AMOVB,
		arm.AMOVBS,
		arm.AMOVBU,
		arm.AMOVFW,
		arm.AMOVWF,
		arm.AMOVDW,
		arm.AMOVWD,
		arm.AMOVFD,
		arm.AMOVDF:
		if p.Scond&(arm.C_WBIT|arm.C_PBIT) != 0 {
			if v.Type == obj.TYPE_REG {
				if p.From.Type == obj.TYPE_MEM || p.From.Type == obj.TYPE_SHIFT {
					if p.From.Reg == v.Reg {
						return 2
					}
				} else {
					if p.To.Reg == v.Reg {
						return 2
					}
				}
			}
		}

		if s != nil {
			if copysub(&p.From, v, s, 1) != 0 {
//.........这里部分代码省略.........

作者:danny800    项目:g   
func buildop(ctxt *obj.Link) {
	var n int

	for i := 0; i < C_NCLASS; i++ {
		for n = 0; n < C_NCLASS; n++ {
			if cmp(n, i) {
				xcmp[i][n] = 1
			}
		}
	}
	for n = 0; optab[n].as != obj.AXXX; n++ {
	}
	sort.Sort(ocmp(optab[:n]))
	for i := 0; i < n; i++ {
		r := optab[i].as
		r0 := r & obj.AMask
		oprange[r0].start = optab[i:]
		for optab[i].as == r {
			i++
		}
		oprange[r0].stop = optab[i:]
		i--

		switch r {
		default:
			ctxt.Diag("unknown op in build: %v", obj.Aconv(int(r)))
			log.Fatalf("bad code")

		case AABSF:
			opset(AMOVFD, r0)
			opset(AMOVDF, r0)
			opset(AMOVWF, r0)
			opset(AMOVFW, r0)
			opset(AMOVWD, r0)
			opset(AMOVDW, r0)
			opset(ANEGF, r0)
			opset(ANEGD, r0)
			opset(AABSD, r0)
			opset(ATRUNCDW, r0)
			opset(ATRUNCFW, r0)
			opset(ATRUNCDV, r0)
			opset(ATRUNCFV, r0)
			opset(AMOVVF, r0)
			opset(AMOVFV, r0)
			opset(AMOVVD, r0)
			opset(AMOVDV, r0)

		case AADD:
			opset(ASGT, r0)
			opset(ASGTU, r0)
			opset(AADDU, r0)
			opset(AADDV, r0)
			opset(AADDVU, r0)

		case AADDF:
			opset(ADIVF, r0)
			opset(ADIVD, r0)
			opset(AMULF, r0)
			opset(AMULD, r0)
			opset(ASUBF, r0)
			opset(ASUBD, r0)
			opset(AADDD, r0)

		case AAND:
			opset(AOR, r0)
			opset(AXOR, r0)

		case ABEQ:
			opset(ABNE, r0)

		case ABLEZ:
			opset(ABGEZ, r0)
			opset(ABGEZAL, r0)
			opset(ABLTZ, r0)
			opset(ABLTZAL, r0)
			opset(ABGTZ, r0)

		case AMOVB:
			opset(AMOVH, r0)

		case AMOVBU:
			opset(AMOVHU, r0)

		case AMUL:
			opset(AREM, r0)
			opset(AREMU, r0)
			opset(ADIVU, r0)
			opset(AMULU, r0)
			opset(ADIV, r0)
			opset(ADIVV, r0)
			opset(ADIVVU, r0)
			opset(AMULV, r0)
			opset(AMULVU, r0)
			opset(AREMV, r0)
			opset(AREMVU, r0)

		case ASLL:
			opset(ASRL, r0)
			opset(ASRA, r0)
			opset(ASLLV, r0)
//.........这里部分代码省略.........


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