Add gops agentv0.10.2-dev

1 files changed, 1005 insertions, 0 deletions

diff --git a/vendor/github.com/google/gops/internal/obj/arm64/obj7.go b/vendor/github.com/google/gops/internal/obj/arm64/obj7.go
new file mode 100644
index 00000000..2d9d1aa7
--- /dev/null
+++ b/vendor/github.com/google/gops/internal/obj/arm64/obj7.go
@@ -0,0 +1,1005 @@
+// cmd/7l/noop.c, cmd/7l/obj.c, cmd/ld/pass.c from Vita Nuova.
+// https://code.google.com/p/ken-cc/source/browse/
+//
+// 	Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved.
+// 	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
+// 	Portions Copyright © 1997-1999 Vita Nuova Limited
+// 	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
+// 	Portions Copyright © 2004,2006 Bruce Ellis
+// 	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
+// 	Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
+// 	Portions Copyright © 2009 The Go Authors. All rights reserved.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package arm64
+
+import (
+	"fmt"
+	"log"
+	"math"
+
+	"github.com/google/gops/internal/obj"
+	"github.com/google/gops/internal/sys"
+)
+
+var complements = []obj.As{
+	AADD:  ASUB,
+	AADDW: ASUBW,
+	ASUB:  AADD,
+	ASUBW: AADDW,
+	ACMP:  ACMN,
+	ACMPW: ACMNW,
+	ACMN:  ACMP,
+	ACMNW: ACMPW,
+}
+
+func stacksplit(ctxt *obj.Link, p *obj.Prog, framesize int32) *obj.Prog {
+	// MOV	g_stackguard(g), R1
+	p = obj.Appendp(ctxt, p)
+
+	p.As = AMOVD
+	p.From.Type = obj.TYPE_MEM
+	p.From.Reg = REGG
+	p.From.Offset = 2 * int64(ctxt.Arch.PtrSize) // G.stackguard0
+	if ctxt.Cursym.CFunc() {
+		p.From.Offset = 3 * int64(ctxt.Arch.PtrSize) // G.stackguard1
+	}
+	p.To.Type = obj.TYPE_REG
+	p.To.Reg = REG_R1
+
+	q := (*obj.Prog)(nil)
+	if framesize <= obj.StackSmall {
+		// small stack: SP < stackguard
+		//	MOV	SP, R2
+		//	CMP	stackguard, R2
+		p = obj.Appendp(ctxt, p)
+
+		p.As = AMOVD
+		p.From.Type = obj.TYPE_REG
+		p.From.Reg = REGSP
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REG_R2
+
+		p = obj.Appendp(ctxt, p)
+		p.As = ACMP
+		p.From.Type = obj.TYPE_REG
+		p.From.Reg = REG_R1
+		p.Reg = REG_R2
+	} else if framesize <= obj.StackBig {
+		// large stack: SP-framesize < stackguard-StackSmall
+		//	SUB	$framesize, SP, R2
+		//	CMP	stackguard, R2
+		p = obj.Appendp(ctxt, p)
+
+		p.As = ASUB
+		p.From.Type = obj.TYPE_CONST
+		p.From.Offset = int64(framesize)
+		p.Reg = REGSP
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REG_R2
+
+		p = obj.Appendp(ctxt, p)
+		p.As = ACMP
+		p.From.Type = obj.TYPE_REG
+		p.From.Reg = REG_R1
+		p.Reg = REG_R2
+	} else {
+		// Such a large stack we need to protect against wraparound
+		// if SP is close to zero.
+		//	SP-stackguard+StackGuard < framesize + (StackGuard-StackSmall)
+		// The +StackGuard on both sides is required to keep the left side positive:
+		// SP is allowed to be slightly below stackguard. See stack.h.
+		//	CMP	$StackPreempt, R1
+		//	BEQ	label_of_call_to_morestack
+		//	ADD	$StackGuard, SP, R2
+		//	SUB	R1, R2
+		//	MOV	$(framesize+(StackGuard-StackSmall)), R3
+		//	CMP	R3, R2
+		p = obj.Appendp(ctxt, p)
+
+		p.As = ACMP
+		p.From.Type = obj.TYPE_CONST
+		p.From.Offset = obj.StackPreempt
+		p.Reg = REG_R1
+
+		p = obj.Appendp(ctxt, p)
+		q = p
+		p.As = ABEQ
+		p.To.Type = obj.TYPE_BRANCH
+
+		p = obj.Appendp(ctxt, p)
+		p.As = AADD
+		p.From.Type = obj.TYPE_CONST
+		p.From.Offset = obj.StackGuard
+		p.Reg = REGSP
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REG_R2
+
+		p = obj.Appendp(ctxt, p)
+		p.As = ASUB
+		p.From.Type = obj.TYPE_REG
+		p.From.Reg = REG_R1
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REG_R2
+
+		p = obj.Appendp(ctxt, p)
+		p.As = AMOVD
+		p.From.Type = obj.TYPE_CONST
+		p.From.Offset = int64(framesize) + (obj.StackGuard - obj.StackSmall)
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REG_R3
+
+		p = obj.Appendp(ctxt, p)
+		p.As = ACMP
+		p.From.Type = obj.TYPE_REG
+		p.From.Reg = REG_R3
+		p.Reg = REG_R2
+	}
+
+	// BLS	do-morestack
+	bls := obj.Appendp(ctxt, p)
+	bls.As = ABLS
+	bls.To.Type = obj.TYPE_BRANCH
+
+	var last *obj.Prog
+	for last = ctxt.Cursym.Text; last.Link != nil; last = last.Link {
+	}
+
+	// Now we are at the end of the function, but logically
+	// we are still in function prologue. We need to fix the
+	// SP data and PCDATA.
+	spfix := obj.Appendp(ctxt, last)
+	spfix.As = obj.ANOP
+	spfix.Spadj = -framesize
+
+	pcdata := obj.Appendp(ctxt, spfix)
+	pcdata.Lineno = ctxt.Cursym.Text.Lineno
+	pcdata.Mode = ctxt.Cursym.Text.Mode
+	pcdata.As = obj.APCDATA
+	pcdata.From.Type = obj.TYPE_CONST
+	pcdata.From.Offset = obj.PCDATA_StackMapIndex
+	pcdata.To.Type = obj.TYPE_CONST
+	pcdata.To.Offset = -1 // pcdata starts at -1 at function entry
+
+	// MOV	LR, R3
+	movlr := obj.Appendp(ctxt, pcdata)
+	movlr.As = AMOVD
+	movlr.From.Type = obj.TYPE_REG
+	movlr.From.Reg = REGLINK
+	movlr.To.Type = obj.TYPE_REG
+	movlr.To.Reg = REG_R3
+	if q != nil {
+		q.Pcond = movlr
+	}
+	bls.Pcond = movlr
+
+	debug := movlr
+	if false {
+		debug = obj.Appendp(ctxt, debug)
+		debug.As = AMOVD
+		debug.From.Type = obj.TYPE_CONST
+		debug.From.Offset = int64(framesize)
+		debug.To.Type = obj.TYPE_REG
+		debug.To.Reg = REGTMP
+	}
+
+	// BL	runtime.morestack(SB)
+	call := obj.Appendp(ctxt, debug)
+	call.As = ABL
+	call.To.Type = obj.TYPE_BRANCH
+	morestack := "runtime.morestack"
+	switch {
+	case ctxt.Cursym.CFunc():
+		morestack = "runtime.morestackc"
+	case ctxt.Cursym.Text.From3.Offset&obj.NEEDCTXT == 0:
+		morestack = "runtime.morestack_noctxt"
+	}
+	call.To.Sym = obj.Linklookup(ctxt, morestack, 0)
+
+	// B	start
+	jmp := obj.Appendp(ctxt, call)
+	jmp.As = AB
+	jmp.To.Type = obj.TYPE_BRANCH
+	jmp.Pcond = ctxt.Cursym.Text.Link
+	jmp.Spadj = +framesize
+
+	// placeholder for bls's jump target
+	// p = obj.Appendp(ctxt, p)
+	// p.As = obj.ANOP
+
+	return bls
+}
+
+func progedit(ctxt *obj.Link, p *obj.Prog) {
+	p.From.Class = 0
+	p.To.Class = 0
+
+	// $0 results in C_ZCON, which matches both C_REG and various
+	// C_xCON, however the C_REG cases in asmout don't expect a
+	// constant, so they will use the register fields and assemble
+	// a R0. To prevent that, rewrite $0 as ZR.
+	if p.From.Type == obj.TYPE_CONST && p.From.Offset == 0 {
+		p.From.Type = obj.TYPE_REG
+		p.From.Reg = REGZERO
+	}
+	if p.To.Type == obj.TYPE_CONST && p.To.Offset == 0 {
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REGZERO
+	}
+
+	// Rewrite BR/BL to symbol as TYPE_BRANCH.
+	switch p.As {
+	case AB,
+		ABL,
+		obj.ARET,
+		obj.ADUFFZERO,
+		obj.ADUFFCOPY:
+		if p.To.Sym != nil {
+			p.To.Type = obj.TYPE_BRANCH
+		}
+		break
+	}
+
+	// Rewrite float constants to values stored in memory.
+	switch p.As {
+	case AFMOVS:
+		if p.From.Type == obj.TYPE_FCONST {
+			f32 := float32(p.From.Val.(float64))
+			i32 := math.Float32bits(f32)
+			if i32 == 0 {
+				p.From.Type = obj.TYPE_REG
+				p.From.Reg = REGZERO
+				break
+			}
+			literal := fmt.Sprintf("$f32.%08x", i32)
+			s := obj.Linklookup(ctxt, literal, 0)
+			s.Size = 4
+			p.From.Type = obj.TYPE_MEM
+			p.From.Sym = s
+			p.From.Sym.Set(obj.AttrLocal, true)
+			p.From.Name = obj.NAME_EXTERN
+			p.From.Offset = 0
+		}
+
+	case AFMOVD:
+		if p.From.Type == obj.TYPE_FCONST {
+			i64 := math.Float64bits(p.From.Val.(float64))
+			if i64 == 0 {
+				p.From.Type = obj.TYPE_REG
+				p.From.Reg = REGZERO
+				break
+			}
+			literal := fmt.Sprintf("$f64.%016x", i64)
+			s := obj.Linklookup(ctxt, literal, 0)
+			s.Size = 8
+			p.From.Type = obj.TYPE_MEM
+			p.From.Sym = s
+			p.From.Sym.Set(obj.AttrLocal, true)
+			p.From.Name = obj.NAME_EXTERN
+			p.From.Offset = 0
+		}
+
+		break
+	}
+
+	// Rewrite negative immediates as positive immediates with
+	// complementary instruction.
+	switch p.As {
+	case AADD, ASUB, ACMP, ACMN:
+		if p.From.Type == obj.TYPE_CONST && p.From.Offset < 0 && p.From.Offset != -1<<63 {
+			p.From.Offset = -p.From.Offset
+			p.As = complements[p.As]
+		}
+	case AADDW, ASUBW, ACMPW, ACMNW:
+		if p.From.Type == obj.TYPE_CONST && p.From.Offset < 0 && int32(p.From.Offset) != -1<<31 {
+			p.From.Offset = -p.From.Offset
+			p.As = complements[p.As]
+		}
+	}
+
+	// For 32-bit logical instruction with constant,
+	// rewrite the high 32-bit to be a repetition of
+	// the low 32-bit, so that the BITCON test can be
+	// shared for both 32-bit and 64-bit. 32-bit ops
+	// will zero the high 32-bit of the destination
+	// register anyway.
+	switch p.As {
+	case AANDW, AORRW, AEORW, AANDSW:
+		if p.From.Type == obj.TYPE_CONST {
+			v := p.From.Offset & 0xffffffff
+			p.From.Offset = v | v<<32
+		}
+	}
+
+	if ctxt.Flag_dynlink {
+		rewriteToUseGot(ctxt, p)
+	}
+}
+
+// Rewrite p, if necessary, to access global data via the global offset table.
+func rewriteToUseGot(ctxt *obj.Link, p *obj.Prog) {
+	if p.As == obj.ADUFFCOPY || p.As == obj.ADUFFZERO {
+		//     ADUFFxxx $offset
+		// becomes
+		//     MOVD runtime.duffxxx@GOT, REGTMP
+		//     ADD $offset, REGTMP
+		//     CALL REGTMP
+		var sym *obj.LSym
+		if p.As == obj.ADUFFZERO {
+			sym = obj.Linklookup(ctxt, "runtime.duffzero", 0)
+		} else {
+			sym = obj.Linklookup(ctxt, "runtime.duffcopy", 0)
+		}
+		offset := p.To.Offset
+		p.As = AMOVD
+		p.From.Type = obj.TYPE_MEM
+		p.From.Name = obj.NAME_GOTREF
+		p.From.Sym = sym
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REGTMP
+		p.To.Name = obj.NAME_NONE
+		p.To.Offset = 0
+		p.To.Sym = nil
+		p1 := obj.Appendp(ctxt, p)
+		p1.As = AADD
+		p1.From.Type = obj.TYPE_CONST
+		p1.From.Offset = offset
+		p1.To.Type = obj.TYPE_REG
+		p1.To.Reg = REGTMP
+		p2 := obj.Appendp(ctxt, p1)
+		p2.As = obj.ACALL
+		p2.To.Type = obj.TYPE_REG
+		p2.To.Reg = REGTMP
+	}
+
+	// We only care about global data: NAME_EXTERN means a global
+	// symbol in the Go sense, and p.Sym.Local is true for a few
+	// internally defined symbols.
+	if p.From.Type == obj.TYPE_ADDR && p.From.Name == obj.NAME_EXTERN && !p.From.Sym.Local() {
+		// MOVD $sym, Rx becomes MOVD sym@GOT, Rx
+		// MOVD $sym+<off>, Rx becomes MOVD sym@GOT, Rx; ADD <off>, Rx
+		if p.As != AMOVD {
+			ctxt.Diag("do not know how to handle TYPE_ADDR in %v with -dynlink", p)
+		}
+		if p.To.Type != obj.TYPE_REG {
+			ctxt.Diag("do not know how to handle LEAQ-type insn to non-register in %v with -dynlink", p)
+		}
+		p.From.Type = obj.TYPE_MEM
+		p.From.Name = obj.NAME_GOTREF
+		if p.From.Offset != 0 {
+			q := obj.Appendp(ctxt, p)
+			q.As = AADD
+			q.From.Type = obj.TYPE_CONST
+			q.From.Offset = p.From.Offset
+			q.To = p.To
+			p.From.Offset = 0
+		}
+	}
+	if p.From3 != nil && p.From3.Name == obj.NAME_EXTERN {
+		ctxt.Diag("don't know how to handle %v with -dynlink", p)
+	}
+	var source *obj.Addr
+	// MOVx sym, Ry becomes MOVD sym@GOT, REGTMP; MOVx (REGTMP), Ry
+	// MOVx Ry, sym becomes MOVD sym@GOT, REGTMP; MOVD Ry, (REGTMP)
+	// An addition may be inserted between the two MOVs if there is an offset.
+	if p.From.Name == obj.NAME_EXTERN && !p.From.Sym.Local() {
+		if p.To.Name == obj.NAME_EXTERN && !p.To.Sym.Local() {
+			ctxt.Diag("cannot handle NAME_EXTERN on both sides in %v with -dynlink", p)
+		}
+		source = &p.From
+	} else if p.To.Name == obj.NAME_EXTERN && !p.To.Sym.Local() {
+		source = &p.To
+	} else {
+		return
+	}
+	if p.As == obj.ATEXT || p.As == obj.AFUNCDATA || p.As == obj.ACALL || p.As == obj.ARET || p.As == obj.AJMP {
+		return
+	}
+	if source.Sym.Type == obj.STLSBSS {
+		return
+	}
+	if source.Type != obj.TYPE_MEM {
+		ctxt.Diag("don't know how to handle %v with -dynlink", p)
+	}
+	p1 := obj.Appendp(ctxt, p)
+	p2 := obj.Appendp(ctxt, p1)
+	p1.As = AMOVD
+	p1.From.Type = obj.TYPE_MEM
+	p1.From.Sym = source.Sym
+	p1.From.Name = obj.NAME_GOTREF
+	p1.To.Type = obj.TYPE_REG
+	p1.To.Reg = REGTMP
+
+	p2.As = p.As
+	p2.From = p.From
+	p2.To = p.To
+	if p.From.Name == obj.NAME_EXTERN {
+		p2.From.Reg = REGTMP
+		p2.From.Name = obj.NAME_NONE
+		p2.From.Sym = nil
+	} else if p.To.Name == obj.NAME_EXTERN {
+		p2.To.Reg = REGTMP
+		p2.To.Name = obj.NAME_NONE
+		p2.To.Sym = nil
+	} else {
+		return
+	}
+	obj.Nopout(p)
+}
+
+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 relinv(a obj.As) obj.As {
+	switch a {
+	case ABEQ:
+		return ABNE
+	case ABNE:
+		return ABEQ
+	case ABCS:
+		return ABCC
+	case ABHS:
+		return ABLO
+	case ABCC:
+		return ABCS
+	case ABLO:
+		return ABHS
+	case ABMI:
+		return ABPL
+	case ABPL:
+		return ABMI
+	case ABVS:
+		return ABVC
+	case ABVC:
+		return ABVS
+	case ABHI:
+		return ABLS
+	case ABLS:
+		return ABHI
+	case ABGE:
+		return ABLT
+	case ABLT:
+		return ABGE
+	case ABGT:
+		return ABLE
+	case ABLE:
+		return ABGT
+	case ACBZ:
+		return ACBNZ
+	case ACBNZ:
+		return ACBZ
+	case ACBZW:
+		return ACBNZW
+	case ACBNZW:
+		return ACBZW
+	}
+
+	log.Fatalf("unknown relation: %s", Anames[a-obj.ABaseARM64])
+	return 0
+}
+
+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("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 || 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("can't 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)
+			if a != obj.ATEXT {
+				if q != nil && (q.Mark&FOLL != 0) {
+					p.As = relinv(a)
+					p.Link = p.Pcond
+					p.Pcond = q
+				}
+			}
+
+			xfol(ctxt, p.Link, last)
+			q = obj.Brchain(ctxt, p.Pcond)
+			if q == nil {
+				q = p.Pcond
+			}
+			if q.Mark&FOLL != 0 {
+				p.Pcond = q
+				return
+			}
+
+			p = q
+			goto loop
+		}
+	}
+
+	p = p.Link
+	goto loop
+}
+
+func preprocess(ctxt *obj.Link, cursym *obj.LSym) {
+	ctxt.Cursym = cursym
+
+	if cursym.Text == nil || cursym.Text.Link == nil {
+		return
+	}
+
+	p := cursym.Text
+	textstksiz := p.To.Offset
+	aoffset := int32(textstksiz)
+
+	cursym.Args = p.To.Val.(int32)
+	cursym.Locals = int32(textstksiz)
+
+	/*
+	 * find leaf subroutines
+	 * strip NOPs
+	 * expand RET
+	 */
+	q := (*obj.Prog)(nil)
+	var q1 *obj.Prog
+	for p := cursym.Text; p != nil; p = p.Link {
+		switch p.As {
+		case obj.ATEXT:
+			p.Mark |= LEAF
+
+		case obj.ARET:
+			break
+
+		case obj.ANOP:
+			q1 = p.Link
+			q.Link = q1 /* q is non-nop */
+			q1.Mark |= p.Mark
+			continue
+
+		case ABL,
+			obj.ADUFFZERO,
+			obj.ADUFFCOPY:
+			cursym.Text.Mark &^= LEAF
+			fallthrough
+
+		case ACBNZ,
+			ACBZ,
+			ACBNZW,
+			ACBZW,
+			ATBZ,
+			ATBNZ,
+			AB,
+			ABEQ,
+			ABNE,
+			ABCS,
+			ABHS,
+			ABCC,
+			ABLO,
+			ABMI,
+			ABPL,
+			ABVS,
+			ABVC,
+			ABHI,
+			ABLS,
+			ABGE,
+			ABLT,
+			ABGT,
+			ABLE,
+			AADR, /* strange */
+			AADRP:
+			q1 = p.Pcond
+
+			if q1 != nil {
+				for q1.As == obj.ANOP {
+					q1 = q1.Link
+					p.Pcond = q1
+				}
+			}
+
+			break
+		}
+
+		q = p
+	}
+
+	var q2 *obj.Prog
+	var retjmp *obj.LSym
+	for p := cursym.Text; p != nil; p = p.Link {
+		o := p.As
+		switch o {
+		case obj.ATEXT:
+			cursym.Text = p
+			if textstksiz < 0 {
+				ctxt.Autosize = 0
+			} else {
+				ctxt.Autosize = int32(textstksiz + 8)
+			}
+			if (cursym.Text.Mark&LEAF != 0) && ctxt.Autosize <= 8 {
+				ctxt.Autosize = 0
+			} else if ctxt.Autosize&(16-1) != 0 {
+				// The frame includes an LR.
+				// If the frame size is 8, it's only an LR,
+				// so there's no potential for breaking references to
+				// local variables by growing the frame size,
+				// because there are no local variables.
+				// But otherwise, if there is a non-empty locals section,
+				// the author of the code is responsible for making sure
+				// that the frame size is 8 mod 16.
+				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.Set(obj.AttrLeaf, true)
+				if ctxt.Autosize == 0 {
+					break
+				}
+			}
+
+			// Frame is non-empty. Make sure to save link register, even if
+			// it is a leaf function, so that traceback works.
+			q = p
+			if ctxt.Autosize > aoffset {
+				// Frame size is too large for a MOVD.W instruction.
+				// Store link register before decrementing SP, so if a signal comes
+				// during the execution of the function prologue, the traceback
+				// code will not see a half-updated stack frame.
+				q = obj.Appendp(ctxt, q)
+				q.Lineno = p.Lineno
+				q.As = ASUB
+				q.From.Type = obj.TYPE_CONST
+				q.From.Offset = int64(ctxt.Autosize)
+				q.Reg = REGSP
+				q.To.Type = obj.TYPE_REG
+				q.To.Reg = REGTMP
+
+				q = obj.Appendp(ctxt, q)
+				q.Lineno = p.Lineno
+				q.As = AMOVD
+				q.From.Type = obj.TYPE_REG
+				q.From.Reg = REGLINK
+				q.To.Type = obj.TYPE_MEM
+				q.To.Reg = REGTMP
+
+				q1 = obj.Appendp(ctxt, q)
+				q1.Lineno = p.Lineno
+				q1.As = AMOVD
+				q1.From.Type = obj.TYPE_REG
+				q1.From.Reg = REGTMP
+				q1.To.Type = obj.TYPE_REG
+				q1.To.Reg = REGSP
+				q1.Spadj = ctxt.Autosize
+			} else {
+				// small frame, update SP and save LR in a single MOVD.W instruction
+				q1 = obj.Appendp(ctxt, q)
+				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.Spadj = aoffset
+			}
+
+			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
+				//	BEQ end
+				//	MOV panic_argp(R1), R2
+				//	ADD $(autosize+8), RSP, R3
+				//	CMP R2, R3
+				//	BNE end
+				//	ADD $8, RSP, R4
+				//	MOVD R4, panic_argp(R1)
+				// end:
+				//	NOP
+				//
+				// The NOP is needed to give the jumps somewhere to land.
+				// It is a liblink NOP, not a ARM64 NOP: it encodes to 0 instruction bytes.
+				q = q1
+
+				q = obj.Appendp(ctxt, q)
+				q.As = AMOVD
+				q.From.Type = obj.TYPE_MEM
+				q.From.Reg = REGG
+				q.From.Offset = 4 * int64(ctxt.Arch.PtrSize) // G.panic
+				q.To.Type = obj.TYPE_REG
+				q.To.Reg = REG_R1
+
+				q = obj.Appendp(ctxt, q)
+				q.As = ACMP
+				q.From.Type = obj.TYPE_REG
+				q.From.Reg = REGZERO
+				q.Reg = REG_R1
+
+				q = obj.Appendp(ctxt, q)
+				q.As = ABEQ
+				q.To.Type = obj.TYPE_BRANCH
+				q1 = q
+
+				q = obj.Appendp(ctxt, q)
+				q.As = AMOVD
+				q.From.Type = obj.TYPE_MEM
+				q.From.Reg = REG_R1
+				q.From.Offset = 0 // Panic.argp
+				q.To.Type = obj.TYPE_REG
+				q.To.Reg = REG_R2
+
+				q = obj.Appendp(ctxt, q)
+				q.As = AADD
+				q.From.Type = obj.TYPE_CONST
+				q.From.Offset = int64(ctxt.Autosize) + 8
+				q.Reg = REGSP
+				q.To.Type = obj.TYPE_REG
+				q.To.Reg = REG_R3
+
+				q = obj.Appendp(ctxt, q)
+				q.As = ACMP
+				q.From.Type = obj.TYPE_REG
+				q.From.Reg = REG_R2
+				q.Reg = REG_R3
+
+				q = obj.Appendp(ctxt, q)
+				q.As = ABNE
+				q.To.Type = obj.TYPE_BRANCH
+				q2 = q
+
+				q = obj.Appendp(ctxt, q)
+				q.As = AADD
+				q.From.Type = obj.TYPE_CONST
+				q.From.Offset = 8
+				q.Reg = REGSP
+				q.To.Type = obj.TYPE_REG
+				q.To.Reg = REG_R4
+
+				q = obj.Appendp(ctxt, q)
+				q.As = AMOVD
+				q.From.Type = obj.TYPE_REG
+				q.From.Reg = REG_R4
+				q.To.Type = obj.TYPE_MEM
+				q.To.Reg = REG_R1
+				q.To.Offset = 0 // Panic.argp
+
+				q = obj.Appendp(ctxt, q)
+
+				q.As = obj.ANOP
+				q1.Pcond = q
+				q2.Pcond = q
+			}
+
+		case obj.ARET:
+			nocache(p)
+			if p.From.Type == obj.TYPE_CONST {
+				ctxt.Diag("using BECOME (%v) is not supported!", p)
+				break
+			}
+
+			retjmp = p.To.Sym
+			p.To = obj.Addr{}
+			if cursym.Text.Mark&LEAF != 0 {
+				if ctxt.Autosize != 0 {
+					p.As = AADD
+					p.From.Type = obj.TYPE_CONST
+					p.From.Offset = int64(ctxt.Autosize)
+					p.To.Type = obj.TYPE_REG
+					p.To.Reg = REGSP
+					p.Spadj = -ctxt.Autosize
+				}
+			} else {
+				/* want write-back pre-indexed SP+autosize -> SP, loading REGLINK*/
+				aoffset = ctxt.Autosize
+
+				if aoffset > 0xF0 {
+					aoffset = 0xF0
+				}
+				p.As = AMOVD
+				p.From.Type = obj.TYPE_MEM
+				p.Scond = C_XPOST
+				p.From.Offset = int64(aoffset)
+				p.From.Reg = REGSP
+				p.To.Type = obj.TYPE_REG
+				p.To.Reg = REGLINK
+				p.Spadj = -aoffset
+				if ctxt.Autosize > aoffset {
+					q = ctxt.NewProg()
+					q.As = AADD
+					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.Link = p.Link
+					q.Spadj = int32(-q.From.Offset)
+					q.Lineno = p.Lineno
+					p.Link = q
+					p = q
+				}
+			}
+
+			if p.As != obj.ARET {
+				q = ctxt.NewProg()
+				q.Lineno = p.Lineno
+				q.Link = p.Link
+				p.Link = q
+				p = q
+			}
+
+			if retjmp != nil { // retjmp
+				p.As = AB
+				p.To.Type = obj.TYPE_BRANCH
+				p.To.Sym = retjmp
+				p.Spadj = +ctxt.Autosize
+				break
+			}
+
+			p.As = obj.ARET
+			p.To.Type = obj.TYPE_MEM
+			p.To.Offset = 0
+			p.To.Reg = REGLINK
+			p.Spadj = +ctxt.Autosize
+
+		case AADD, ASUB:
+			if p.To.Type == obj.TYPE_REG && p.To.Reg == REGSP && p.From.Type == obj.TYPE_CONST {
+				if p.As == AADD {
+					p.Spadj = int32(-p.From.Offset)
+				} else {
+					p.Spadj = int32(+p.From.Offset)
+				}
+			}
+			break
+		}
+	}
+}
+
+func nocache(p *obj.Prog) {
+	p.Optab = 0
+	p.From.Class = 0
+	p.To.Class = 0
+}
+
+var unaryDst = map[obj.As]bool{
+	AWORD:  true,
+	ADWORD: true,
+	ABL:    true,
+	AB:     true,
+	ASVC:   true,
+}
+
+var Linkarm64 = obj.LinkArch{
+	Arch:       sys.ArchARM64,
+	Preprocess: preprocess,
+	Assemble:   span7,
+	Follow:     follow,
+	Progedit:   progedit,
+	UnaryDst:   unaryDst,
+}