Golang Value.Reg方法代碼示例

// push pushes v onto the floating-point stack.  v must be in a register.
func push(s *gc.SSAGenState, v *ssa.Value) {
	p := gc.Prog(x86.AFMOVD)
	p.From.Type = obj.TYPE_REG
	p.From.Reg = s.SSEto387[v.Reg()]
	p.To.Type = obj.TYPE_REG
	p.To.Reg = x86.REG_F0
}

func ssaGenISEL(v *ssa.Value, cr int64, r1, r2 int16) {
	r := v.Reg()
	p := gc.Prog(ppc64.AISEL)
	p.To.Type = obj.TYPE_REG
	p.To.Reg = r
	p.Reg = r1
	p.From3 = &obj.Addr{Type: obj.TYPE_REG, Reg: r2}
	p.From.Type = obj.TYPE_CONST
	p.From.Offset = cr
}

// popAndSave pops a value off of the floating-point stack and stores
// it in the reigster assigned to v.
func popAndSave(s *gc.SSAGenState, v *ssa.Value) {
	r := v.Reg()
	if _, ok := s.SSEto387[r]; ok {
		// Pop value, write to correct register.
		p := gc.Prog(x86.AFMOVDP)
		p.From.Type = obj.TYPE_REG
		p.From.Reg = x86.REG_F0
		p.To.Type = obj.TYPE_REG
		p.To.Reg = s.SSEto387[v.Reg()] + 1
	} else {
		// Don't actually pop value. This 387 register is now the
		// new home for the not-yet-assigned-a-home SSE register.
		// Increase the register mapping of all other registers by one.
		for rSSE, r387 := range s.SSEto387 {
			s.SSEto387[rSSE] = r387 + 1
		}
		s.SSEto387[r] = x86.REG_F0
	}
}

func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
	s.SetLineno(v.Line)
	switch v.Op {
	case ssa.OpInitMem:
		// memory arg needs no code
	case ssa.OpArg:
		// input args need no code
	case ssa.OpSP, ssa.OpSB, ssa.OpGetG:
		// nothing to do
	case ssa.OpCopy, ssa.OpARMMOVWconvert, ssa.OpARMMOVWreg:
		if v.Type.IsMemory() {
			return
		}
		x := v.Args[0].Reg()
		y := v.Reg()
		if x == y {
			return
		}
		as := arm.AMOVW
		if v.Type.IsFloat() {
			switch v.Type.Size() {
			case 4:
				as = arm.AMOVF
			case 8:
				as = arm.AMOVD
			default:
				panic("bad float size")
			}
		}
		p := gc.Prog(as)
		p.From.Type = obj.TYPE_REG
		p.From.Reg = x
		p.To.Type = obj.TYPE_REG
		p.To.Reg = y
	case ssa.OpARMMOVWnop:
		if v.Reg() != v.Args[0].Reg() {
			v.Fatalf("input[0] and output not in same register %s", v.LongString())
		}
		// nothing to do
	case ssa.OpLoadReg:
		if v.Type.IsFlags() {
			v.Fatalf("load flags not implemented: %v", v.LongString())
			return
		}
		p := gc.Prog(loadByType(v.Type))
		gc.AddrAuto(&p.From, v.Args[0])
		p.To.Type = obj.TYPE_REG
		p.To.Reg = v.Reg()
	case ssa.OpPhi:
		gc.CheckLoweredPhi(v)
	case ssa.OpStoreReg:
		if v.Type.IsFlags() {
			v.Fatalf("store flags not implemented: %v", v.LongString())
			return
		}
		p := gc.Prog(storeByType(v.Type))
		p.From.Type = obj.TYPE_REG
		p.From.Reg = v.Args[0].Reg()
		gc.AddrAuto(&p.To, v)
	case ssa.OpARMUDIVrtcall:
		p := gc.Prog(obj.ACALL)
		p.To.Type = obj.TYPE_MEM
		p.To.Name = obj.NAME_EXTERN
		p.To.Sym = obj.Linklookup(gc.Ctxt, "udiv", 0)
	case ssa.OpARMADD,
		ssa.OpARMADC,
		ssa.OpARMSUB,
		ssa.OpARMSBC,
		ssa.OpARMRSB,
		ssa.OpARMAND,
		ssa.OpARMOR,
		ssa.OpARMXOR,
		ssa.OpARMBIC,
		ssa.OpARMMUL,
		ssa.OpARMADDF,
		ssa.OpARMADDD,
		ssa.OpARMSUBF,
		ssa.OpARMSUBD,
		ssa.OpARMMULF,
		ssa.OpARMMULD,
		ssa.OpARMDIVF,
		ssa.OpARMDIVD:
		r := v.Reg()
		r1 := v.Args[0].Reg()
		r2 := v.Args[1].Reg()
		p := gc.Prog(v.Op.Asm())
		p.From.Type = obj.TYPE_REG
		p.From.Reg = r2
		p.Reg = r1
		p.To.Type = obj.TYPE_REG
		p.To.Reg = r
	case ssa.OpARMADDS,
		ssa.OpARMSUBS:
		r := v.Reg0()
		r1 := v.Args[0].Reg()
		r2 := v.Args[1].Reg()
		p := gc.Prog(v.Op.Asm())
		p.Scond = arm.C_SBIT
		p.From.Type = obj.TYPE_REG
		p.From.Reg = r2
//.........這裏部分代碼省略.........

func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
	s.SetLineno(v.Line)
	switch v.Op {
	case ssa.OpInitMem:
		// memory arg needs no code
	case ssa.OpArg:
		// input args need no code
	case ssa.OpSP, ssa.OpSB, ssa.OpGetG:
		// nothing to do
	case ssa.OpSelect0, ssa.OpSelect1:
		// nothing to do
	case ssa.OpCopy, ssa.OpMIPSMOVWconvert, ssa.OpMIPSMOVWreg:
		t := v.Type
		if t.IsMemory() {
			return
		}
		x := v.Args[0].Reg()
		y := v.Reg()
		if x == y {
			return
		}
		as := mips.AMOVW
		if isFPreg(x) && isFPreg(y) {
			as = mips.AMOVF
			if t.Size() == 8 {
				as = mips.AMOVD
			}
		}

		p := gc.Prog(as)
		p.From.Type = obj.TYPE_REG
		p.From.Reg = x
		p.To.Type = obj.TYPE_REG
		p.To.Reg = y
		if isHILO(x) && isHILO(y) || isHILO(x) && isFPreg(y) || isFPreg(x) && isHILO(y) {
			// cannot move between special registers, use TMP as intermediate
			p.To.Reg = mips.REGTMP
			p = gc.Prog(mips.AMOVW)
			p.From.Type = obj.TYPE_REG
			p.From.Reg = mips.REGTMP
			p.To.Type = obj.TYPE_REG
			p.To.Reg = y
		}
	case ssa.OpMIPSMOVWnop:
		if v.Reg() != v.Args[0].Reg() {
			v.Fatalf("input[0] and output not in same register %s", v.LongString())
		}
		// nothing to do
	case ssa.OpLoadReg:
		if v.Type.IsFlags() {
			v.Fatalf("load flags not implemented: %v", v.LongString())
			return
		}
		r := v.Reg()
		p := gc.Prog(loadByType(v.Type, r))
		gc.AddrAuto(&p.From, v.Args[0])
		p.To.Type = obj.TYPE_REG
		p.To.Reg = r
		if isHILO(r) {
			// cannot directly load, load to TMP and move
			p.To.Reg = mips.REGTMP
			p = gc.Prog(mips.AMOVW)
			p.From.Type = obj.TYPE_REG
			p.From.Reg = mips.REGTMP
			p.To.Type = obj.TYPE_REG
			p.To.Reg = r
		}
	case ssa.OpStoreReg:
		if v.Type.IsFlags() {
			v.Fatalf("store flags not implemented: %v", v.LongString())
			return
		}
		r := v.Args[0].Reg()
		if isHILO(r) {
			// cannot directly store, move to TMP and store
			p := gc.Prog(mips.AMOVW)
			p.From.Type = obj.TYPE_REG
			p.From.Reg = r
			p.To.Type = obj.TYPE_REG
			p.To.Reg = mips.REGTMP
			r = mips.REGTMP
		}
		p := gc.Prog(storeByType(v.Type, r))
		p.From.Type = obj.TYPE_REG
		p.From.Reg = r
		gc.AddrAuto(&p.To, v)
	case ssa.OpMIPSADD,
		ssa.OpMIPSSUB,
		ssa.OpMIPSAND,
		ssa.OpMIPSOR,
		ssa.OpMIPSXOR,
		ssa.OpMIPSNOR,
		ssa.OpMIPSSLL,
		ssa.OpMIPSSRL,
		ssa.OpMIPSSRA,
		ssa.OpMIPSADDF,
		ssa.OpMIPSADDD,
		ssa.OpMIPSSUBF,
		ssa.OpMIPSSUBD,
		ssa.OpMIPSMULF,
//.........這裏部分代碼省略.........

// Generates code for v using 387 instructions.  Reports whether
// the instruction was handled by this routine.
func ssaGenValue387(s *gc.SSAGenState, v *ssa.Value) bool {
	// The SSA compiler pretends that it has an SSE backend.
	// If we don't have one of those, we need to translate
	// all the SSE ops to equivalent 387 ops. That's what this
	// function does.

	switch v.Op {
	case ssa.Op386MOVSSconst, ssa.Op386MOVSDconst:
		p := gc.Prog(loadPush(v.Type))
		p.From.Type = obj.TYPE_FCONST
		p.From.Val = math.Float64frombits(uint64(v.AuxInt))
		p.To.Type = obj.TYPE_REG
		p.To.Reg = x86.REG_F0
		popAndSave(s, v)
		return true
	case ssa.Op386MOVSSconst2, ssa.Op386MOVSDconst2:
		p := gc.Prog(loadPush(v.Type))
		p.From.Type = obj.TYPE_MEM
		p.From.Reg = v.Args[0].Reg()
		p.To.Type = obj.TYPE_REG
		p.To.Reg = x86.REG_F0
		popAndSave(s, v)
		return true

	case ssa.Op386MOVSSload, ssa.Op386MOVSDload, ssa.Op386MOVSSloadidx1, ssa.Op386MOVSDloadidx1, ssa.Op386MOVSSloadidx4, ssa.Op386MOVSDloadidx8:
		p := gc.Prog(loadPush(v.Type))
		p.From.Type = obj.TYPE_MEM
		p.From.Reg = v.Args[0].Reg()
		gc.AddAux(&p.From, v)
		switch v.Op {
		case ssa.Op386MOVSSloadidx1, ssa.Op386MOVSDloadidx1:
			p.From.Scale = 1
			p.From.Index = v.Args[1].Reg()
		case ssa.Op386MOVSSloadidx4:
			p.From.Scale = 4
			p.From.Index = v.Args[1].Reg()
		case ssa.Op386MOVSDloadidx8:
			p.From.Scale = 8
			p.From.Index = v.Args[1].Reg()
		}
		p.To.Type = obj.TYPE_REG
		p.To.Reg = x86.REG_F0
		popAndSave(s, v)
		return true

	case ssa.Op386MOVSSstore, ssa.Op386MOVSDstore:
		// Push to-be-stored value on top of stack.
		push(s, v.Args[1])

		// Pop and store value.
		var op obj.As
		switch v.Op {
		case ssa.Op386MOVSSstore:
			op = x86.AFMOVFP
		case ssa.Op386MOVSDstore:
			op = x86.AFMOVDP
		}
		p := gc.Prog(op)
		p.From.Type = obj.TYPE_REG
		p.From.Reg = x86.REG_F0
		p.To.Type = obj.TYPE_MEM
		p.To.Reg = v.Args[0].Reg()
		gc.AddAux(&p.To, v)
		return true

	case ssa.Op386MOVSSstoreidx1, ssa.Op386MOVSDstoreidx1, ssa.Op386MOVSSstoreidx4, ssa.Op386MOVSDstoreidx8:
		push(s, v.Args[2])
		var op obj.As
		switch v.Op {
		case ssa.Op386MOVSSstoreidx1, ssa.Op386MOVSSstoreidx4:
			op = x86.AFMOVFP
		case ssa.Op386MOVSDstoreidx1, ssa.Op386MOVSDstoreidx8:
			op = x86.AFMOVDP
		}
		p := gc.Prog(op)
		p.From.Type = obj.TYPE_REG
		p.From.Reg = x86.REG_F0
		p.To.Type = obj.TYPE_MEM
		p.To.Reg = v.Args[0].Reg()
		gc.AddAux(&p.To, v)
		switch v.Op {
		case ssa.Op386MOVSSstoreidx1, ssa.Op386MOVSDstoreidx1:
			p.To.Scale = 1
			p.To.Index = v.Args[1].Reg()
		case ssa.Op386MOVSSstoreidx4:
			p.To.Scale = 4
			p.To.Index = v.Args[1].Reg()
		case ssa.Op386MOVSDstoreidx8:
			p.To.Scale = 8
			p.To.Index = v.Args[1].Reg()
		}
		return true

	case ssa.Op386ADDSS, ssa.Op386ADDSD, ssa.Op386SUBSS, ssa.Op386SUBSD,
		ssa.Op386MULSS, ssa.Op386MULSD, ssa.Op386DIVSS, ssa.Op386DIVSD:
		if v.Reg() != v.Args[0].Reg() {
			v.Fatalf("input[0] and output not in same register %s", v.LongString())
		}
//.........這裏部分代碼省略.........

func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
	s.SetLineno(v.Line)
	switch v.Op {
	case ssa.OpS390XSLD, ssa.OpS390XSLW,
		ssa.OpS390XSRD, ssa.OpS390XSRW,
		ssa.OpS390XSRAD, ssa.OpS390XSRAW:
		r := v.Reg()
		r1 := v.Args[0].Reg()
		r2 := v.Args[1].Reg()
		if r2 == s390x.REG_R0 {
			v.Fatalf("cannot use R0 as shift value %s", v.LongString())
		}
		p := opregreg(v.Op.Asm(), r, r2)
		if r != r1 {
			p.Reg = r1
		}
	case ssa.OpS390XADD, ssa.OpS390XADDW,
		ssa.OpS390XSUB, ssa.OpS390XSUBW,
		ssa.OpS390XAND, ssa.OpS390XANDW,
		ssa.OpS390XOR, ssa.OpS390XORW,
		ssa.OpS390XXOR, ssa.OpS390XXORW:
		r := v.Reg()
		r1 := v.Args[0].Reg()
		r2 := v.Args[1].Reg()
		p := opregreg(v.Op.Asm(), r, r2)
		if r != r1 {
			p.Reg = r1
		}
	// 2-address opcode arithmetic
	case ssa.OpS390XMULLD, ssa.OpS390XMULLW,
		ssa.OpS390XMULHD, ssa.OpS390XMULHDU,
		ssa.OpS390XFADDS, ssa.OpS390XFADD, ssa.OpS390XFSUBS, ssa.OpS390XFSUB,
		ssa.OpS390XFMULS, ssa.OpS390XFMUL, ssa.OpS390XFDIVS, ssa.OpS390XFDIV:
		r := v.Reg()
		if r != v.Args[0].Reg() {
			v.Fatalf("input[0] and output not in same register %s", v.LongString())
		}
		opregreg(v.Op.Asm(), r, v.Args[1].Reg())
	case ssa.OpS390XDIVD, ssa.OpS390XDIVW,
		ssa.OpS390XDIVDU, ssa.OpS390XDIVWU,
		ssa.OpS390XMODD, ssa.OpS390XMODW,
		ssa.OpS390XMODDU, ssa.OpS390XMODWU:

		// TODO(mundaym): use the temp registers every time like x86 does with AX?
		dividend := v.Args[0].Reg()
		divisor := v.Args[1].Reg()

		// CPU faults upon signed overflow, which occurs when most
		// negative int is divided by -1.
		var j *obj.Prog
		if v.Op == ssa.OpS390XDIVD || v.Op == ssa.OpS390XDIVW ||
			v.Op == ssa.OpS390XMODD || v.Op == ssa.OpS390XMODW {

			var c *obj.Prog
			c = gc.Prog(s390x.ACMP)
			j = gc.Prog(s390x.ABEQ)

			c.From.Type = obj.TYPE_REG
			c.From.Reg = divisor
			c.To.Type = obj.TYPE_CONST
			c.To.Offset = -1

			j.To.Type = obj.TYPE_BRANCH

		}

		p := gc.Prog(v.Op.Asm())
		p.From.Type = obj.TYPE_REG
		p.From.Reg = divisor
		p.Reg = 0
		p.To.Type = obj.TYPE_REG
		p.To.Reg = dividend

		// signed division, rest of the check for -1 case
		if j != nil {
			j2 := gc.Prog(s390x.ABR)
			j2.To.Type = obj.TYPE_BRANCH

			var n *obj.Prog
			if v.Op == ssa.OpS390XDIVD || v.Op == ssa.OpS390XDIVW {
				// n * -1 = -n
				n = gc.Prog(s390x.ANEG)
				n.To.Type = obj.TYPE_REG
				n.To.Reg = dividend
			} else {
				// n % -1 == 0
				n = gc.Prog(s390x.AXOR)
				n.From.Type = obj.TYPE_REG
				n.From.Reg = dividend
				n.To.Type = obj.TYPE_REG
				n.To.Reg = dividend
			}

			j.To.Val = n
			j2.To.Val = s.Pc()
		}
	case ssa.OpS390XADDconst, ssa.OpS390XADDWconst:
		opregregimm(v.Op.Asm(), v.Reg(), v.Args[0].Reg(), v.AuxInt)
	case ssa.OpS390XMULLDconst, ssa.OpS390XMULLWconst,
		ssa.OpS390XSUBconst, ssa.OpS390XSUBWconst,
//.........這裏部分代碼省略.........