Golang Link.NewProg方法代码示例

func follow(ctxt *obj.Link, s *obj.LSym) {
	ctxt.Cursym = s

	firstp := ctxt.NewProg()
	lastp := firstp
	xfol(ctxt, s.Text, &lastp)
	lastp.Link = nil
	s.Text = firstp.Link
}

func addnop(ctxt *obj.Link, p *obj.Prog) {
	q := ctxt.NewProg()
	// we want to use the canonical NOP (SLL $0,R0,R0) here,
	// however, as the assembler will always replace $0
	// as R0, we have to resort to manually encode the SLL
	// instruction as WORD $0.
	q.As = AWORD
	q.Lineno = p.Lineno
	q.From.Type = obj.TYPE_CONST
	q.From.Name = obj.NAME_NONE
	q.From.Offset = 0

	q.Link = p.Link
	p.Link = q
}

func span0(ctxt *obj.Link, cursym *obj.LSym) {
	p := cursym.Text
	if p == nil || p.Link == nil { // handle external functions and ELF section symbols
		return
	}
	ctxt.Cursym = cursym
	ctxt.Autosize = int32(p.To.Offset + 8)

	if oprange[AOR&obj.AMask].start == nil {
		buildop(ctxt)
	}

	c := int64(0)
	p.Pc = c

	var m int
	var o *Optab
	for p = p.Link; p != nil; p = p.Link {
		ctxt.Curp = p
		p.Pc = c
		o = oplook(ctxt, p)
		m = int(o.size)
		if m == 0 {
			if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != obj.AUSEFIELD {
				ctxt.Diag("zero-width instruction\n%v", p)
			}
			continue
		}

		c += int64(m)
	}

	cursym.Size = c

	/*
	 * if any procedure is large enough to
	 * generate a large SBRA branch, then
	 * generate extra passes putting branches
	 * around jmps to fix. this is rare.
	 */
	bflag := 1

	var otxt int64
	var q *obj.Prog
	for bflag != 0 {
		if ctxt.Debugvlog != 0 {
			fmt.Fprintf(ctxt.Bso, "%5.2f span1\n", obj.Cputime())
		}
		bflag = 0
		c = 0
		for p = cursym.Text.Link; p != nil; p = p.Link {
			p.Pc = c
			o = oplook(ctxt, p)

			// very large conditional branches
			if o.type_ == 6 && p.Pcond != nil {
				otxt = p.Pcond.Pc - c
				if otxt < -(1<<17)+10 || otxt >= (1<<17)-10 {
					q = ctxt.NewProg()
					q.Link = p.Link
					p.Link = q
					q.As = AJMP
					q.Lineno = p.Lineno
					q.To.Type = obj.TYPE_BRANCH
					q.Pcond = p.Pcond
					p.Pcond = q
					q = ctxt.NewProg()
					q.Link = p.Link
					p.Link = q
					q.As = AJMP
					q.Lineno = p.Lineno
					q.To.Type = obj.TYPE_BRANCH
					q.Pcond = q.Link.Link

					addnop(ctxt, p.Link)
					addnop(ctxt, p)
					bflag = 1
				}
			}

			m = int(o.size)
			if m == 0 {
				if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != obj.AUSEFIELD {
					ctxt.Diag("zero-width instruction\n%v", p)
				}
				continue
			}

			c += int64(m)
		}

		cursym.Size = c
	}

	c += -c & (FuncAlign - 1)
	cursym.Size = c

	/*
	 * lay out the code, emitting code and data relocations.
	 */
//.........这里部分代码省略.........

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

loop:
	if p == nil {
		return
	}
	a = int(p.As)
	if a == AB {
		q = p.Pcond
		if q != nil && q.As != obj.ATEXT {
			p.Mark |= FOLL
			p = q
			if p.Mark&FOLL == 0 {
				goto loop
			}
		}
	}

	if p.Mark&FOLL != 0 {
		i = 0
		q = p
		for ; i < 4; i, q = i+1, q.Link {
			if q == *last || q == nil {
				break
			}
			a = int(q.As)
			if a == obj.ANOP {
				i--
				continue
			}

			if a == AB || (a == obj.ARET && q.Scond == C_SCOND_NONE) || a == ARFE || a == obj.AUNDEF {
				goto copy
			}
			if q.Pcond == nil || (q.Pcond.Mark&FOLL != 0) {
				continue
			}
			if a != ABEQ && a != ABNE {
				continue
			}

		copy:
			for {
				r = ctxt.NewProg()
				*r = *p
				if r.Mark&FOLL == 0 {
					fmt.Printf("can't happen 1\n")
				}
				r.Mark |= FOLL
				if p != q {
					p = p.Link
					(*last).Link = r
					*last = r
					continue
				}

				(*last).Link = r
				*last = r
				if a == AB || (a == obj.ARET && q.Scond == C_SCOND_NONE) || a == ARFE || a == obj.AUNDEF {
					return
				}
				r.As = ABNE
				if a == ABNE {
					r.As = ABEQ
				}
				r.Pcond = p.Link
				r.Link = p.Pcond
				if r.Link.Mark&FOLL == 0 {
					xfol(ctxt, r.Link, last)
				}
				if r.Pcond.Mark&FOLL == 0 {
					fmt.Printf("can't happen 2\n")
				}
				return
			}
		}

		a = AB
		q = ctxt.NewProg()
		q.As = int16(a)
		q.Lineno = p.Lineno
		q.To.Type = obj.TYPE_BRANCH
		q.To.Offset = p.Pc
		q.Pcond = p
		p = q
	}

	p.Mark |= FOLL
	(*last).Link = p
	*last = p
	if a == AB || (a == obj.ARET && p.Scond == C_SCOND_NONE) || a == ARFE || a == obj.AUNDEF {
		return
	}

	if p.Pcond != nil {
		if a != ABL && a != ABX && p.Link != nil {
//.........这里部分代码省略.........

func softfloat(ctxt *obj.Link, cursym *obj.LSym) {
	if ctxt.Goarm > 5 {
		return
	}

	symsfloat := obj.Linklookup(ctxt, "_sfloat", 0)

	wasfloat := 0
	for p := cursym.Text; p != nil; p = p.Link {
		if p.Pcond != nil {
			p.Pcond.Mark |= LABEL
		}
	}
	var next *obj.Prog
	for p := cursym.Text; p != nil; p = p.Link {
		switch p.As {
		case AMOVW:
			if isfloatreg(&p.To) || isfloatreg(&p.From) {
				goto soft
			}
			goto notsoft

		case AMOVWD,
			AMOVWF,
			AMOVDW,
			AMOVFW,
			AMOVFD,
			AMOVDF,
			AMOVF,
			AMOVD,
			ACMPF,
			ACMPD,
			AADDF,
			AADDD,
			ASUBF,
			ASUBD,
			AMULF,
			AMULD,
			ADIVF,
			ADIVD,
			ASQRTF,
			ASQRTD,
			AABSF,
			AABSD:
			goto soft

		default:
			goto notsoft
		}

	soft:
		if wasfloat == 0 || (p.Mark&LABEL != 0) {
			next = ctxt.NewProg()
			*next = *p

			// BL _sfloat(SB)
			*p = obj.Prog{}
			p.Ctxt = ctxt
			p.Link = next
			p.As = ABL
			p.To.Type = obj.TYPE_BRANCH
			p.To.Sym = symsfloat
			p.Lineno = next.Lineno

			p = next
			wasfloat = 1
		}

		continue

	notsoft:
		wasfloat = 0
	}
}

//.........这里部分代码省略.........
				p2.Pcond = q
			}

		case obj.ARET:
			if p.From.Type == obj.TYPE_CONST {
				ctxt.Diag("using BECOME (%v) is not supported!", p)
				break
			}

			retTarget := p.To.Sym

			if cursym.Text.Mark&LEAF != 0 {
				if autosize == 0 {
					p.As = ABR
					p.From = obj.Addr{}
					if retTarget == nil {
						p.To.Type = obj.TYPE_REG
						p.To.Reg = REG_LR
					} else {
						p.To.Type = obj.TYPE_BRANCH
						p.To.Sym = retTarget
					}
					p.Mark |= BRANCH
					break
				}

				p.As = AADD
				p.From.Type = obj.TYPE_CONST
				p.From.Offset = int64(autosize)
				p.To.Type = obj.TYPE_REG
				p.To.Reg = REGSP
				p.Spadj = -autosize

				q = ctxt.NewProg()
				q.As = ABR
				q.Lineno = p.Lineno
				q.To.Type = obj.TYPE_REG
				q.To.Reg = REG_LR
				q.Mark |= BRANCH
				q.Spadj = +autosize

				q.Link = p.Link
				p.Link = q
				break
			}

			p.As = AMOVD
			p.From.Type = obj.TYPE_MEM
			p.From.Offset = 0
			p.From.Reg = REGSP
			p.To.Type = obj.TYPE_REG
			p.To.Reg = REGTMP

			q = ctxt.NewProg()
			q.As = AMOVD
			q.Lineno = p.Lineno
			q.From.Type = obj.TYPE_REG
			q.From.Reg = REGTMP
			q.To.Type = obj.TYPE_REG
			q.To.Reg = REG_LR

			q.Link = p.Link
			p.Link = q
			p = q

			if false {

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

loop:
	if p == nil {
		return
	}
	a = int(p.As)
	if a == ABR {
		q = p.Pcond
		if (p.Mark&NOSCHED != 0) || q != nil && (q.Mark&NOSCHED != 0) {
			p.Mark |= FOLL
			(*last).Link = p
			*last = p
			p = p.Link
			xfol(ctxt, p, last)
			p = q
			if p != nil && p.Mark&FOLL == 0 {
				goto loop
			}
			return
		}

		if q != nil {
			p.Mark |= FOLL
			p = q
			if p.Mark&FOLL == 0 {
				goto loop
			}
		}
	}

	if p.Mark&FOLL != 0 {
		i = 0
		q = p
		for ; i < 4; i, q = i+1, q.Link {
			if q == *last || (q.Mark&NOSCHED != 0) {
				break
			}
			b = 0 /* set */
			a = int(q.As)
			if a == obj.ANOP {
				i--
				continue
			}

			if a == ABR || a == obj.ARET || a == ARFI || a == ARFCI || a == ARFID || a == AHRFID {
				goto copy
			}
			if q.Pcond == nil || (q.Pcond.Mark&FOLL != 0) {
				continue
			}
			b = relinv(a)
			if b == 0 {
				continue
			}

		copy:
			for {
				r = ctxt.NewProg()
				*r = *p
				if r.Mark&FOLL == 0 {
					fmt.Printf("cant happen 1\n")
				}
				r.Mark |= FOLL
				if p != q {
					p = p.Link
					(*last).Link = r
					*last = r
					continue
				}

				(*last).Link = r
				*last = r
				if a == ABR || a == obj.ARET || a == ARFI || a == ARFCI || a == ARFID || a == AHRFID {
					return
				}
				r.As = int16(b)
				r.Pcond = p.Link
				r.Link = p.Pcond
				if r.Link.Mark&FOLL == 0 {
					xfol(ctxt, r.Link, last)
				}
				if r.Pcond.Mark&FOLL == 0 {
					fmt.Printf("cant happen 2\n")
				}
				return
			}
		}

		a = ABR
		q = ctxt.NewProg()
		q.As = int16(a)
		q.Lineno = p.Lineno
		q.To.Type = obj.TYPE_BRANCH
		q.To.Offset = p.Pc
//.........这里部分代码省略.........

//.........这里部分代码省略.........
				if ctxt.Autosize == 8 {
					ctxt.Autosize += 8
					cursym.Locals += 8
				} else {
					ctxt.Diag("%v: unaligned frame size %d - must be 8 mod 16 (or 0)", p, ctxt.Autosize-8)
				}
			}
			p.To.Offset = int64(ctxt.Autosize) - 8
			if ctxt.Autosize == 0 && !(cursym.Text.Mark&LEAF != 0) {
				if ctxt.Debugvlog != 0 {
					ctxt.Logf("save suppressed in: %s\n", cursym.Text.From.Sym.Name)
				}
				cursym.Text.Mark |= LEAF
			}

			if !(p.From3.Offset&obj.NOSPLIT != 0) {
				p = stacksplit(ctxt, p, ctxt.Autosize) // emit split check
			}

			aoffset = ctxt.Autosize
			if aoffset > 0xF0 {
				aoffset = 0xF0
			}
			if cursym.Text.Mark&LEAF != 0 {
				cursym.Leaf = true
				if ctxt.Autosize == 0 {
					break
				}
				aoffset = 0
			}

			q = p
			if ctxt.Autosize > aoffset {
				q = ctxt.NewProg()
				q.As = ASUB
				q.Lineno = p.Lineno
				q.From.Type = obj.TYPE_CONST
				q.From.Offset = int64(ctxt.Autosize) - int64(aoffset)
				q.To.Type = obj.TYPE_REG
				q.To.Reg = REGSP
				q.Spadj = int32(q.From.Offset)
				q.Link = p.Link
				p.Link = q
				if cursym.Text.Mark&LEAF != 0 {
					break
				}
			}

			q1 = ctxt.NewProg()
			q1.As = AMOVD
			q1.Lineno = p.Lineno
			q1.From.Type = obj.TYPE_REG
			q1.From.Reg = REGLINK
			q1.To.Type = obj.TYPE_MEM
			q1.Scond = C_XPRE
			q1.To.Offset = int64(-aoffset)
			q1.To.Reg = REGSP
			q1.Link = q.Link
			q1.Spadj = aoffset
			q.Link = q1

			if cursym.Text.From3.Offset&obj.WRAPPER != 0 {
				// if(g->panic != nil && g->panic->argp == FP) g->panic->argp = bottom-of-frame
				//
				//	MOV g_panic(g), R1
				//	CMP ZR, R1

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
		for ; i < 4; i, q = i+1, q.Link {
			if q == nil {
				break
			}
			if q == *last {
				break
			}
			a = q.As
			if a == obj.ANOP {
				i--
				continue
			}

			if nofollow(a) || pushpop(a) {
				break // NOTE(rsc): arm does goto copy
			}
			if q.Pcond == nil || q.Pcond.Mark&DONE != 0 {
				continue
			}
			if a == obj.ACALL || a == ALOOP {
				continue
			}
			for {
				if p.As == obj.ANOP {
					p = p.Link
					continue
				}

				q = obj.Copyp(ctxt, p)
				p = p.Link
				q.Mark |= DONE
				(*last).Link = q
				*last = q
				if q.As != a || q.Pcond == nil || q.Pcond.Mark&DONE != 0 {
					continue
				}

				q.As = relinv(q.As)
				p = q.Pcond
				q.Pcond = q.Link
				q.Link = p
				xfol(ctxt, q.Link, last)
				p = q.Link
				if p.Mark&DONE != 0 {
					return
				}
				goto loop
				/* */
			}
		}
		q = ctxt.NewProg()
		q.As = obj.AJMP
		q.Lineno = p.Lineno
		q.To.Type = obj.TYPE_BRANCH
		q.To.Offset = p.Pc
		q.Pcond = p
		p = q
	}

	/* emit p */
	p.Mark |= DONE

	(*last).Link = p
	*last = p
	a = p.As

	/* continue loop with what comes after p */
	if nofollow(a) {
		return
	}
	if p.Pcond != nil && a != obj.ACALL {
//.........这里部分代码省略.........

//.........这里部分代码省略.........
			if p.From.Type == obj.TYPE_CONST {
				ctxt.Diag("using BECOME (%v) is not supported!", p)
				break
			}

			retSym := p.To.Sym
			p.To.Name = obj.NAME_NONE // clear fields as we may modify p to other instruction
			p.To.Sym = nil

			if cursym.Text.Mark&LEAF != 0 {
				if autosize == 0 {
					p.As = AJMP
					p.From = obj.Addr{}
					if retSym != nil { // retjmp
						p.To.Type = obj.TYPE_BRANCH
						p.To.Name = obj.NAME_EXTERN
						p.To.Sym = retSym
					} else {
						p.To.Type = obj.TYPE_MEM
						p.To.Reg = REGLINK
						p.To.Offset = 0
					}
					p.Mark |= BRANCH
					break
				}

				p.As = add
				p.From.Type = obj.TYPE_CONST
				p.From.Offset = int64(autosize)
				p.To.Type = obj.TYPE_REG
				p.To.Reg = REGSP
				p.Spadj = -autosize

				q = ctxt.NewProg()
				q.As = AJMP
				q.Lineno = p.Lineno
				q.To.Type = obj.TYPE_MEM
				q.To.Offset = 0
				q.To.Reg = REGLINK
				q.Mark |= BRANCH
				q.Spadj = +autosize

				q.Link = p.Link
				p.Link = q
				break
			}

			p.As = mov
			p.From.Type = obj.TYPE_MEM
			p.From.Offset = 0
			p.From.Reg = REGSP
			p.To.Type = obj.TYPE_REG
			p.To.Reg = REG_R4
			if retSym != nil { // retjmp from non-leaf, need to restore LINK register
				p.To.Reg = REGLINK
			}

			if autosize != 0 {
				q = ctxt.NewProg()
				q.As = add
				q.Lineno = p.Lineno
				q.From.Type = obj.TYPE_CONST
				q.From.Offset = int64(autosize)
				q.To.Type = obj.TYPE_REG
				q.To.Reg = REGSP
				q.Spadj = -autosize

func xfol(ctxt *obj.Link, p *obj.Prog, last **obj.Prog) {
	var q *obj.Prog
	var r *obj.Prog
	var b obj.As

	for p != nil {
		a := p.As
		if a == ABR {
			q = p.Pcond
			if (p.Mark&NOSCHED != 0) || q != nil && (q.Mark&NOSCHED != 0) {
				p.Mark |= FOLL
				(*last).Link = p
				*last = p
				(*last).Pc = pc_cnt
				pc_cnt += 1
				p = p.Link
				xfol(ctxt, p, last)
				p = q
				if p != nil && p.Mark&FOLL == 0 {
					continue
				}
				return
			}

			if q != nil {
				p.Mark |= FOLL
				p = q
				if p.Mark&FOLL == 0 {
					continue
				}
			}
		}

		if p.Mark&FOLL != 0 {
			q = p
			for i := 0; i < 4; i, q = i+1, q.Link {
				if q == *last || (q.Mark&NOSCHED != 0) {
					break
				}
				b = 0 /* set */
				a = q.As
				if a == obj.ANOP {
					i--
					continue
				}
				if a != ABR && a != obj.ARET {
					if q.Pcond == nil || (q.Pcond.Mark&FOLL != 0) {
						continue
					}
					b = relinv(a)
					if b == 0 {
						continue
					}
				}

				for {
					r = ctxt.NewProg()
					*r = *p
					if r.Mark&FOLL == 0 {
						fmt.Printf("can't happen 1\n")
					}
					r.Mark |= FOLL
					if p != q {
						p = p.Link
						(*last).Link = r
						*last = r
						(*last).Pc = pc_cnt
						pc_cnt += 1
						continue
					}

					(*last).Link = r
					*last = r
					(*last).Pc = pc_cnt
					pc_cnt += 1
					if a == ABR || a == obj.ARET {
						return
					}
					r.As = b
					r.Pcond = p.Link
					r.Link = p.Pcond
					if r.Link.Mark&FOLL == 0 {
						xfol(ctxt, r.Link, last)
					}
					if r.Pcond.Mark&FOLL == 0 {
						fmt.Printf("can't happen 2\n")
					}
					return
				}
			}

			a = ABR
			q = ctxt.NewProg()
			q.As = a
			q.Lineno = p.Lineno
			q.To.Type = obj.TYPE_BRANCH
			q.To.Offset = p.Pc
			q.Pcond = p
			p = q
		}
//.........这里部分代码省略.........

//.........这里部分代码省略.........
				p2.Pcond = q
			}

		case ARET:
			if p.From.Type == obj.TYPE_CONST {
				ctxt.Diag("using BECOME (%v) is not supported!", p)
				break
			}

			if p.To.Sym != nil { // retjmp
				p.As = AJMP
				p.To.Type = obj.TYPE_BRANCH
				break
			}

			if cursym.Text.Mark&LEAF != 0 {
				if autosize == 0 {
					p.As = AJMP
					p.From = obj.Addr{}
					p.To.Type = obj.TYPE_MEM
					p.To.Offset = 0
					p.To.Reg = REGLINK
					p.Mark |= BRANCH
					break
				}

				p.As = AADDV
				p.From.Type = obj.TYPE_CONST
				p.From.Offset = int64(autosize)
				p.To.Type = obj.TYPE_REG
				p.To.Reg = REGSP
				p.Spadj = -autosize

				q = ctxt.NewProg()
				q.As = AJMP
				q.Lineno = p.Lineno
				q.To.Type = obj.TYPE_MEM
				q.To.Offset = 0
				q.To.Reg = REGLINK
				q.Mark |= BRANCH
				q.Spadj = +autosize

				q.Link = p.Link
				p.Link = q
				break
			}

			p.As = AMOVV
			p.From.Type = obj.TYPE_MEM
			p.From.Offset = 0
			p.From.Reg = REGSP
			p.To.Type = obj.TYPE_REG
			p.To.Reg = REG_R4

			if false {
				// Debug bad returns
				q = ctxt.NewProg()

				q.As = AMOVV
				q.Lineno = p.Lineno
				q.From.Type = obj.TYPE_MEM
				q.From.Offset = 0
				q.From.Reg = REG_R4
				q.To.Type = obj.TYPE_REG
				q.To.Reg = REGTMP

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

loop:
	if p == nil {
		return
	}
	a := p.As
	if a == AB {
		q = p.Pcond
		if q != nil {
			p.Mark |= FOLL
			p = q
			if !(p.Mark&FOLL != 0) {
				goto loop
			}
		}
	}

	if p.Mark&FOLL != 0 {
		i = 0
		q = p
		for ; i < 4; i, q = i+1, q.Link {
			if q == *last || q == nil {
				break
			}
			a = q.As
			if a == obj.ANOP {
				i--
				continue
			}

			if a == AB || a == obj.ARET || a == AERET {
				goto copy
			}
			if q.Pcond == nil || (q.Pcond.Mark&FOLL != 0) {
				continue
			}
			if a != ABEQ && a != ABNE {
				continue
			}

		copy:
			for {
				r = ctxt.NewProg()
				*r = *p
				if !(r.Mark&FOLL != 0) {
					fmt.Printf("cant happen 1\n")
				}
				r.Mark |= FOLL
				if p != q {
					p = p.Link
					(*last).Link = r
					*last = r
					continue
				}

				(*last).Link = r
				*last = r
				if a == AB || a == obj.ARET || a == AERET {
					return
				}
				if a == ABNE {
					r.As = ABEQ
				} else {
					r.As = ABNE
				}
				r.Pcond = p.Link
				r.Link = p.Pcond
				if !(r.Link.Mark&FOLL != 0) {
					xfol(ctxt, r.Link, last)
				}
				if !(r.Pcond.Mark&FOLL != 0) {
					fmt.Printf("cant happen 2\n")
				}
				return
			}
		}

		a = AB
		q = ctxt.NewProg()
		q.As = a
		q.Lineno = p.Lineno
		q.To.Type = obj.TYPE_BRANCH
		q.To.Offset = p.Pc
		q.Pcond = p
		p = q
	}

	p.Mark |= FOLL
	(*last).Link = p
	*last = p
	if a == AB || a == obj.ARET || a == AERET {
		return
	}
	if p.Pcond != nil {
		if a != ABL && p.Link != nil {
			q = obj.Brchain(ctxt, p.Link)
//.........这里部分代码省略.........

//.........这里部分代码省略.........
				ctxt.Autosize = 0
			} else if ctxt.Autosize&(16-1) != 0 {
				stkadj = 16 - (int64(ctxt.Autosize) & (16 - 1))
				ctxt.Autosize += int32(stkadj)
				cursym.Locals += int32(stkadj)
			}
			p.To.Offset = int64(ctxt.Autosize) - 8
			if ctxt.Autosize == 0 && !(cursym.Text.Mark&LEAF != 0) {
				if ctxt.Debugvlog != 0 {
					fmt.Fprintf(ctxt.Bso, "save suppressed in: %s\n", cursym.Text.From.Sym.Name)
				}
				obj.Bflush(ctxt.Bso)
				cursym.Text.Mark |= LEAF
			}

			if !(p.From3.Offset&obj.NOSPLIT != 0) {
				p = stacksplit(ctxt, p, ctxt.Autosize, bool2int(cursym.Text.From3.Offset&obj.NEEDCTXT == 0)) // emit split check
			}

			aoffset = ctxt.Autosize
			if aoffset > 0xF0 {
				aoffset = 0xF0
			}
			if cursym.Text.Mark&LEAF != 0 {
				cursym.Leaf = 1
				if ctxt.Autosize == 0 {
					break
				}
				aoffset = 0
			}

			q = p
			if ctxt.Autosize > aoffset {
				q = ctxt.NewProg()
				q.As = ASUB
				q.Lineno = p.Lineno
				q.From.Type = obj.TYPE_CONST
				q.From.Offset = int64(ctxt.Autosize) - int64(aoffset)
				q.To.Type = obj.TYPE_REG
				q.To.Reg = REGSP
				q.Spadj = int32(q.From.Offset)
				q.Link = p.Link
				p.Link = q
				if cursym.Text.Mark&LEAF != 0 {
					break
				}
			}

			q1 = ctxt.NewProg()
			q1.As = AMOVD
			q1.Lineno = p.Lineno
			q1.From.Type = obj.TYPE_REG
			q1.From.Reg = REGLINK
			q1.To.Type = obj.TYPE_MEM
			q1.Scond = C_XPRE
			q1.To.Offset = int64(-aoffset)
			q1.To.Reg = REGSP
			q1.Link = q.Link
			q1.Spadj = aoffset
			q.Link = q1

			if cursym.Text.From3.Offset&obj.WRAPPER != 0 {
				// if(g->panic != nil && g->panic->argp == FP) g->panic->argp = bottom-of-frame
				//
				//	MOV g_panic(g), R1
				//	CMP ZR, R1

//.........这里部分代码省略.........
				p1.Pcond = q
				p2.Pcond = q
			}

		case ARETURN:
			if p.From.Type == obj.TYPE_CONST {
				ctxt.Diag("using BECOME (%v) is not supported!", p)
				break
			}

			if p.To.Sym != nil { // retjmp
				p.As = ABR
				p.To.Type = obj.TYPE_BRANCH
				break
			}

			if cursym.Text.Mark&LEAF != 0 {
				if autosize == 0 {
					p.As = ABR
					p.From = obj.Addr{}
					p.To.Type = obj.TYPE_REG
					p.To.Reg = REG_LR
					p.Mark |= BRANCH
					break
				}

				p.As = AADD
				p.From.Type = obj.TYPE_CONST
				p.From.Offset = int64(autosize)
				p.To.Type = obj.TYPE_REG
				p.To.Reg = REGSP
				p.Spadj = -autosize

				q = ctxt.NewProg()
				q.As = ABR
				q.Lineno = p.Lineno
				q.To.Type = obj.TYPE_REG
				q.To.Reg = REG_LR
				q.Mark |= BRANCH
				q.Spadj = +autosize

				q.Link = p.Link
				p.Link = q
				break
			}

			p.As = AMOVD
			p.From.Type = obj.TYPE_MEM
			p.From.Offset = 0
			p.From.Reg = REGSP
			p.To.Type = obj.TYPE_REG
			p.To.Reg = REGTMP

			q = ctxt.NewProg()
			q.As = AMOVD
			q.Lineno = p.Lineno
			q.From.Type = obj.TYPE_REG
			q.From.Reg = REGTMP
			q.To.Type = obj.TYPE_REG
			q.To.Reg = REG_LR

			q.Link = p.Link
			p.Link = q
			p = q

			if false {