Adding upstream version 1.21.8.upstream/1.21.8

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1412 insertions, 0 deletions

diff --git a/src/cmd/internal/obj/ppc64/obj9.go b/src/cmd/internal/obj/ppc64/obj9.go
new file mode 100644
index 0000000..02831b8
--- /dev/null
+++ b/src/cmd/internal/obj/ppc64/obj9.go
@@ -0,0 +1,1412 @@
+// cmd/9l/noop.c, cmd/9l/pass.c, cmd/9l/span.c from Vita Nuova.
+//
+//	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 © 2000-2008 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 © 2000-2008 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 ppc64
+
+import (
+	"cmd/internal/obj"
+	"cmd/internal/objabi"
+	"cmd/internal/src"
+	"cmd/internal/sys"
+	"internal/abi"
+	"log"
+)
+
+func progedit(ctxt *obj.Link, p *obj.Prog, newprog obj.ProgAlloc) {
+	p.From.Class = 0
+	p.To.Class = 0
+
+	c := ctxt9{ctxt: ctxt, newprog: newprog}
+
+	// Rewrite BR/BL to symbol as TYPE_BRANCH.
+	switch p.As {
+	case ABR,
+		ABL,
+		obj.ARET,
+		obj.ADUFFZERO,
+		obj.ADUFFCOPY:
+		if p.To.Sym != nil {
+			p.To.Type = obj.TYPE_BRANCH
+		}
+	}
+
+	// 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))
+			p.From.Type = obj.TYPE_MEM
+			p.From.Sym = ctxt.Float32Sym(f32)
+			p.From.Name = obj.NAME_EXTERN
+			p.From.Offset = 0
+		}
+
+	case AFMOVD:
+		if p.From.Type == obj.TYPE_FCONST {
+			f64 := p.From.Val.(float64)
+			// Constant not needed in memory for float +/- 0
+			if f64 != 0 {
+				p.From.Type = obj.TYPE_MEM
+				p.From.Sym = ctxt.Float64Sym(f64)
+				p.From.Name = obj.NAME_EXTERN
+				p.From.Offset = 0
+			}
+		}
+
+	case AMOVD:
+		// 32b constants (signed and unsigned) can be generated via 1 or 2 instructions.
+		// All others must be placed in memory and loaded.
+		isS32 := int64(int32(p.From.Offset)) == p.From.Offset
+		isU32 := uint64(uint32(p.From.Offset)) == uint64(p.From.Offset)
+		if p.From.Type == obj.TYPE_CONST && p.From.Name == obj.NAME_NONE && p.From.Reg == 0 && !isS32 && !isU32 {
+			p.From.Type = obj.TYPE_MEM
+			p.From.Sym = ctxt.Int64Sym(p.From.Offset)
+			p.From.Name = obj.NAME_EXTERN
+			p.From.Offset = 0
+		}
+	}
+
+	switch p.As {
+	// Rewrite SUB constants into ADD.
+	case ASUBC:
+		if p.From.Type == obj.TYPE_CONST {
+			p.From.Offset = -p.From.Offset
+			p.As = AADDC
+		}
+
+	case ASUBCCC:
+		if p.From.Type == obj.TYPE_CONST {
+			p.From.Offset = -p.From.Offset
+			p.As = AADDCCC
+		}
+
+	case ASUB:
+		if p.From.Type == obj.TYPE_CONST {
+			p.From.Offset = -p.From.Offset
+			p.As = AADD
+		}
+
+	// To maintain backwards compatibility, we accept some 4 argument usage of
+	// several opcodes which was likely not intended, but did work. These are not
+	// added to optab to avoid the chance this behavior might be used with newer
+	// instructions.
+	//
+	// Rewrite argument ordering like "ADDEX R3, $3, R4, R5" into
+	//                                "ADDEX R3, R4, $3, R5"
+	case AVSHASIGMAW, AVSHASIGMAD, AADDEX, AXXSLDWI, AXXPERMDI:
+		if len(p.RestArgs) == 2 && p.Reg == 0 && p.RestArgs[0].Addr.Type == obj.TYPE_CONST && p.RestArgs[1].Addr.Type == obj.TYPE_REG {
+			p.Reg = p.RestArgs[1].Addr.Reg
+			p.RestArgs = p.RestArgs[:1]
+		}
+	}
+
+	if c.ctxt.Headtype == objabi.Haix {
+		c.rewriteToUseTOC(p)
+	} else if c.ctxt.Flag_dynlink {
+		c.rewriteToUseGot(p)
+	}
+}
+
+// Rewrite p, if necessary, to access a symbol using its TOC anchor.
+// This code is for AIX only.
+func (c *ctxt9) rewriteToUseTOC(p *obj.Prog) {
+	if p.As == obj.ATEXT || p.As == obj.AFUNCDATA || p.As == obj.ACALL || p.As == obj.ARET || p.As == obj.AJMP {
+		return
+	}
+
+	if p.As == obj.ADUFFCOPY || p.As == obj.ADUFFZERO {
+		// ADUFFZERO/ADUFFCOPY is considered as an ABL except in dynamic
+		// link where it should be an indirect call.
+		if !c.ctxt.Flag_dynlink {
+			return
+		}
+		//     ADUFFxxx $offset
+		// becomes
+		//     MOVD runtime.duffxxx@TOC, R12
+		//     ADD $offset, R12
+		//     MOVD R12, LR
+		//     BL (LR)
+		var sym *obj.LSym
+		if p.As == obj.ADUFFZERO {
+			sym = c.ctxt.Lookup("runtime.duffzero")
+		} else {
+			sym = c.ctxt.Lookup("runtime.duffcopy")
+		}
+		// Retrieve or create the TOC anchor.
+		symtoc := c.ctxt.LookupInit("TOC."+sym.Name, func(s *obj.LSym) {
+			s.Type = objabi.SDATA
+			s.Set(obj.AttrDuplicateOK, true)
+			s.Set(obj.AttrStatic, true)
+			c.ctxt.Data = append(c.ctxt.Data, s)
+			s.WriteAddr(c.ctxt, 0, 8, sym, 0)
+		})
+
+		offset := p.To.Offset
+		p.As = AMOVD
+		p.From.Type = obj.TYPE_MEM
+		p.From.Name = obj.NAME_TOCREF
+		p.From.Sym = symtoc
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REG_R12
+		p.To.Name = obj.NAME_NONE
+		p.To.Offset = 0
+		p.To.Sym = nil
+		p1 := obj.Appendp(p, c.newprog)
+		p1.As = AADD
+		p1.From.Type = obj.TYPE_CONST
+		p1.From.Offset = offset
+		p1.To.Type = obj.TYPE_REG
+		p1.To.Reg = REG_R12
+		p2 := obj.Appendp(p1, c.newprog)
+		p2.As = AMOVD
+		p2.From.Type = obj.TYPE_REG
+		p2.From.Reg = REG_R12
+		p2.To.Type = obj.TYPE_REG
+		p2.To.Reg = REG_LR
+		p3 := obj.Appendp(p2, c.newprog)
+		p3.As = obj.ACALL
+		p3.To.Type = obj.TYPE_REG
+		p3.To.Reg = REG_LR
+	}
+
+	var source *obj.Addr
+	if p.From.Name == obj.NAME_EXTERN || p.From.Name == obj.NAME_STATIC {
+		if p.From.Type == obj.TYPE_ADDR {
+			if p.As == ADWORD {
+				// ADWORD $sym doesn't need TOC anchor
+				return
+			}
+			if p.As != AMOVD {
+				c.ctxt.Diag("do not know how to handle TYPE_ADDR in %v", p)
+				return
+			}
+			if p.To.Type != obj.TYPE_REG {
+				c.ctxt.Diag("do not know how to handle LEAQ-type insn to non-register in %v", p)
+				return
+			}
+		} else if p.From.Type != obj.TYPE_MEM {
+			c.ctxt.Diag("do not know how to handle %v without TYPE_MEM", p)
+			return
+		}
+		source = &p.From
+
+	} else if p.To.Name == obj.NAME_EXTERN || p.To.Name == obj.NAME_STATIC {
+		if p.To.Type != obj.TYPE_MEM {
+			c.ctxt.Diag("do not know how to handle %v without TYPE_MEM", p)
+			return
+		}
+		if source != nil {
+			c.ctxt.Diag("cannot handle symbols on both sides in %v", p)
+			return
+		}
+		source = &p.To
+	} else {
+		return
+
+	}
+
+	if source.Sym == nil {
+		c.ctxt.Diag("do not know how to handle nil symbol in %v", p)
+		return
+	}
+
+	if source.Sym.Type == objabi.STLSBSS {
+		return
+	}
+
+	// Retrieve or create the TOC anchor.
+	symtoc := c.ctxt.LookupInit("TOC."+source.Sym.Name, func(s *obj.LSym) {
+		s.Type = objabi.SDATA
+		s.Set(obj.AttrDuplicateOK, true)
+		s.Set(obj.AttrStatic, true)
+		c.ctxt.Data = append(c.ctxt.Data, s)
+		s.WriteAddr(c.ctxt, 0, 8, source.Sym, 0)
+	})
+
+	if source.Type == obj.TYPE_ADDR {
+		// MOVD $sym, Rx becomes MOVD symtoc, Rx
+		// MOVD $sym+<off>, Rx becomes MOVD symtoc, Rx; ADD <off>, Rx
+		p.From.Type = obj.TYPE_MEM
+		p.From.Sym = symtoc
+		p.From.Name = obj.NAME_TOCREF
+
+		if p.From.Offset != 0 {
+			q := obj.Appendp(p, c.newprog)
+			q.As = AADD
+			q.From.Type = obj.TYPE_CONST
+			q.From.Offset = p.From.Offset
+			p.From.Offset = 0
+			q.To = p.To
+		}
+		return
+
+	}
+
+	// MOVx sym, Ry becomes MOVD symtoc, REGTMP; MOVx (REGTMP), Ry
+	// MOVx Ry, sym becomes MOVD symtoc, REGTMP; MOVx Ry, (REGTMP)
+	// An addition may be inserted between the two MOVs if there is an offset.
+
+	q := obj.Appendp(p, c.newprog)
+	q.As = AMOVD
+	q.From.Type = obj.TYPE_MEM
+	q.From.Sym = symtoc
+	q.From.Name = obj.NAME_TOCREF
+	q.To.Type = obj.TYPE_REG
+	q.To.Reg = REGTMP
+
+	q = obj.Appendp(q, c.newprog)
+	q.As = p.As
+	q.From = p.From
+	q.To = p.To
+	if p.From.Name != obj.NAME_NONE {
+		q.From.Type = obj.TYPE_MEM
+		q.From.Reg = REGTMP
+		q.From.Name = obj.NAME_NONE
+		q.From.Sym = nil
+	} else if p.To.Name != obj.NAME_NONE {
+		q.To.Type = obj.TYPE_MEM
+		q.To.Reg = REGTMP
+		q.To.Name = obj.NAME_NONE
+		q.To.Sym = nil
+	} else {
+		c.ctxt.Diag("unreachable case in rewriteToUseTOC with %v", p)
+	}
+
+	obj.Nopout(p)
+}
+
+// Rewrite p, if necessary, to access global data via the global offset table.
+func (c *ctxt9) rewriteToUseGot(p *obj.Prog) {
+	if p.As == obj.ADUFFCOPY || p.As == obj.ADUFFZERO {
+		//     ADUFFxxx $offset
+		// becomes
+		//     MOVD runtime.duffxxx@GOT, R12
+		//     ADD $offset, R12
+		//     MOVD R12, LR
+		//     BL (LR)
+		var sym *obj.LSym
+		if p.As == obj.ADUFFZERO {
+			sym = c.ctxt.LookupABI("runtime.duffzero", obj.ABIInternal)
+		} else {
+			sym = c.ctxt.LookupABI("runtime.duffcopy", obj.ABIInternal)
+		}
+		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 = REG_R12
+		p.To.Name = obj.NAME_NONE
+		p.To.Offset = 0
+		p.To.Sym = nil
+		p1 := obj.Appendp(p, c.newprog)
+		p1.As = AADD
+		p1.From.Type = obj.TYPE_CONST
+		p1.From.Offset = offset
+		p1.To.Type = obj.TYPE_REG
+		p1.To.Reg = REG_R12
+		p2 := obj.Appendp(p1, c.newprog)
+		p2.As = AMOVD
+		p2.From.Type = obj.TYPE_REG
+		p2.From.Reg = REG_R12
+		p2.To.Type = obj.TYPE_REG
+		p2.To.Reg = REG_LR
+		p3 := obj.Appendp(p2, c.newprog)
+		p3.As = obj.ACALL
+		p3.To.Type = obj.TYPE_REG
+		p3.To.Reg = REG_LR
+	}
+
+	// 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 {
+			c.ctxt.Diag("do not know how to handle TYPE_ADDR in %v with -dynlink", p)
+		}
+		if p.To.Type != obj.TYPE_REG {
+			c.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(p, c.newprog)
+			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.GetFrom3() != nil && p.GetFrom3().Name == obj.NAME_EXTERN {
+		c.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; MOVx 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() {
+			c.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 == objabi.STLSBSS {
+		return
+	}
+	if source.Type != obj.TYPE_MEM {
+		c.ctxt.Diag("don't know how to handle %v with -dynlink", p)
+	}
+	p1 := obj.Appendp(p, c.newprog)
+	p2 := obj.Appendp(p1, c.newprog)
+
+	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 preprocess(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) {
+	// TODO(minux): add morestack short-cuts with small fixed frame-size.
+	if cursym.Func().Text == nil || cursym.Func().Text.Link == nil {
+		return
+	}
+
+	c := ctxt9{ctxt: ctxt, cursym: cursym, newprog: newprog}
+
+	p := c.cursym.Func().Text
+	textstksiz := p.To.Offset
+	if textstksiz == -8 {
+		// Compatibility hack.
+		p.From.Sym.Set(obj.AttrNoFrame, true)
+		textstksiz = 0
+	}
+	if textstksiz%8 != 0 {
+		c.ctxt.Diag("frame size %d not a multiple of 8", textstksiz)
+	}
+	if p.From.Sym.NoFrame() {
+		if textstksiz != 0 {
+			c.ctxt.Diag("NOFRAME functions must have a frame size of 0, not %d", textstksiz)
+		}
+	}
+
+	c.cursym.Func().Args = p.To.Val.(int32)
+	c.cursym.Func().Locals = int32(textstksiz)
+
+	/*
+	 * find leaf subroutines
+	 * expand RET
+	 * expand BECOME pseudo
+	 */
+
+	var q *obj.Prog
+	var q1 *obj.Prog
+	for p := c.cursym.Func().Text; p != nil; p = p.Link {
+		switch p.As {
+		/* too hard, just leave alone */
+		case obj.ATEXT:
+			q = p
+
+			p.Mark |= LABEL | LEAF | SYNC
+			if p.Link != nil {
+				p.Link.Mark |= LABEL
+			}
+
+		case ANOR:
+			q = p
+			if p.To.Type == obj.TYPE_REG {
+				if p.To.Reg == REGZERO {
+					p.Mark |= LABEL | SYNC
+				}
+			}
+
+		case ALWAR,
+			ALBAR,
+			ASTBCCC,
+			ASTWCCC,
+			AEIEIO,
+			AICBI,
+			AISYNC,
+			ATLBIE,
+			ATLBIEL,
+			ASLBIA,
+			ASLBIE,
+			ASLBMFEE,
+			ASLBMFEV,
+			ASLBMTE,
+			ADCBF,
+			ADCBI,
+			ADCBST,
+			ADCBT,
+			ADCBTST,
+			ADCBZ,
+			ASYNC,
+			ATLBSYNC,
+			APTESYNC,
+			ALWSYNC,
+			ATW,
+			AWORD,
+			ARFI,
+			ARFCI,
+			ARFID,
+			AHRFID:
+			q = p
+			p.Mark |= LABEL | SYNC
+			continue
+
+		case AMOVW, AMOVWZ, AMOVD:
+			q = p
+			if p.From.Reg >= REG_SPECIAL || p.To.Reg >= REG_SPECIAL {
+				p.Mark |= LABEL | SYNC
+			}
+			continue
+
+		case AFABS,
+			AFABSCC,
+			AFADD,
+			AFADDCC,
+			AFCTIW,
+			AFCTIWCC,
+			AFCTIWZ,
+			AFCTIWZCC,
+			AFDIV,
+			AFDIVCC,
+			AFMADD,
+			AFMADDCC,
+			AFMOVD,
+			AFMOVDU,
+			/* case AFMOVDS: */
+			AFMOVS,
+			AFMOVSU,
+
+			/* case AFMOVSD: */
+			AFMSUB,
+			AFMSUBCC,
+			AFMUL,
+			AFMULCC,
+			AFNABS,
+			AFNABSCC,
+			AFNEG,
+			AFNEGCC,
+			AFNMADD,
+			AFNMADDCC,
+			AFNMSUB,
+			AFNMSUBCC,
+			AFRSP,
+			AFRSPCC,
+			AFSUB,
+			AFSUBCC:
+			q = p
+
+			p.Mark |= FLOAT
+			continue
+
+		case ABL,
+			ABCL,
+			obj.ADUFFZERO,
+			obj.ADUFFCOPY:
+			c.cursym.Func().Text.Mark &^= LEAF
+			fallthrough
+
+		case ABC,
+			ABEQ,
+			ABGE,
+			ABGT,
+			ABLE,
+			ABLT,
+			ABNE,
+			ABR,
+			ABVC,
+			ABVS:
+			p.Mark |= BRANCH
+			q = p
+			q1 = p.To.Target()
+			if q1 != nil {
+				// NOPs are not removed due to #40689.
+
+				if q1.Mark&LEAF == 0 {
+					q1.Mark |= LABEL
+				}
+			} else {
+				p.Mark |= LABEL
+			}
+			q1 = p.Link
+			if q1 != nil {
+				q1.Mark |= LABEL
+			}
+			continue
+
+		case AFCMPO, AFCMPU:
+			q = p
+			p.Mark |= FCMP | FLOAT
+			continue
+
+		case obj.ARET:
+			q = p
+			if p.Link != nil {
+				p.Link.Mark |= LABEL
+			}
+			continue
+
+		case obj.ANOP:
+			// NOPs are not removed due to
+			// #40689
+			continue
+
+		default:
+			q = p
+			continue
+		}
+	}
+
+	autosize := int32(0)
+	var p1 *obj.Prog
+	var p2 *obj.Prog
+	for p := c.cursym.Func().Text; p != nil; p = p.Link {
+		o := p.As
+		switch o {
+		case obj.ATEXT:
+			autosize = int32(textstksiz)
+
+			if p.Mark&LEAF != 0 && autosize == 0 {
+				// A leaf function with no locals has no frame.
+				p.From.Sym.Set(obj.AttrNoFrame, true)
+			}
+
+			if !p.From.Sym.NoFrame() {
+				// If there is a stack frame at all, it includes
+				// space to save the LR.
+				autosize += int32(c.ctxt.Arch.FixedFrameSize)
+			}
+
+			if p.Mark&LEAF != 0 && autosize < abi.StackSmall {
+				// A leaf function with a small stack can be marked
+				// NOSPLIT, avoiding a stack check.
+				p.From.Sym.Set(obj.AttrNoSplit, true)
+			}
+
+			p.To.Offset = int64(autosize)
+
+			q = p
+
+			if NeedTOCpointer(c.ctxt) && c.cursym.Name != "runtime.duffzero" && c.cursym.Name != "runtime.duffcopy" {
+				// When compiling Go into PIC, without PCrel support, all functions must start
+				// with instructions to load the TOC pointer into r2:
+				//
+				//	addis r2, r12, .TOC.-func@ha
+				//	addi r2, r2, .TOC.-func@l+4
+				//
+				// We could probably skip this prologue in some situations
+				// but it's a bit subtle. However, it is both safe and
+				// necessary to leave the prologue off duffzero and
+				// duffcopy as we rely on being able to jump to a specific
+				// instruction offset for them.
+				//
+				// These are AWORDS because there is no (afaict) way to
+				// generate the addis instruction except as part of the
+				// load of a large constant, and in that case there is no
+				// way to use r12 as the source.
+				//
+				// Note that the same condition is tested in
+				// putelfsym in cmd/link/internal/ld/symtab.go
+				// where we set the st_other field to indicate
+				// the presence of these instructions.
+				q = obj.Appendp(q, c.newprog)
+				q.As = AWORD
+				q.Pos = p.Pos
+				q.From.Type = obj.TYPE_CONST
+				q.From.Offset = 0x3c4c0000
+				q = obj.Appendp(q, c.newprog)
+				q.As = AWORD
+				q.Pos = p.Pos
+				q.From.Type = obj.TYPE_CONST
+				q.From.Offset = 0x38420000
+				rel := obj.Addrel(c.cursym)
+				rel.Off = 0
+				rel.Siz = 8
+				rel.Sym = c.ctxt.Lookup(".TOC.")
+				rel.Type = objabi.R_ADDRPOWER_PCREL
+			}
+
+			if !c.cursym.Func().Text.From.Sym.NoSplit() {
+				q = c.stacksplit(q, autosize) // emit split check
+			}
+
+			if autosize != 0 {
+				var prologueEnd *obj.Prog
+				// Save the link register and update the SP.  MOVDU is used unless
+				// the frame size is too large.  The link register must be saved
+				// even for non-empty leaf functions so that traceback works.
+				if autosize >= -BIG && autosize <= BIG {
+					// Use MOVDU to adjust R1 when saving R31, if autosize is small.
+					q = obj.Appendp(q, c.newprog)
+					q.As = AMOVD
+					q.Pos = p.Pos
+					q.From.Type = obj.TYPE_REG
+					q.From.Reg = REG_LR
+					q.To.Type = obj.TYPE_REG
+					q.To.Reg = REGTMP
+					prologueEnd = q
+
+					q = obj.Appendp(q, c.newprog)
+					q.As = AMOVDU
+					q.Pos = p.Pos
+					q.From.Type = obj.TYPE_REG
+					q.From.Reg = REGTMP
+					q.To.Type = obj.TYPE_MEM
+					q.To.Offset = int64(-autosize)
+					q.To.Reg = REGSP
+					q.Spadj = autosize
+				} else {
+					// Frame size is too large for a MOVDU 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.
+					// This sequence is not async preemptible, as if we open a frame
+					// at the current SP, it will clobber the saved LR.
+					q = obj.Appendp(q, c.newprog)
+					q.As = AMOVD
+					q.Pos = p.Pos
+					q.From.Type = obj.TYPE_REG
+					q.From.Reg = REG_LR
+					q.To.Type = obj.TYPE_REG
+					q.To.Reg = REG_R29 // REGTMP may be used to synthesize large offset in the next instruction
+
+					q = c.ctxt.StartUnsafePoint(q, c.newprog)
+
+					q = obj.Appendp(q, c.newprog)
+					q.As = AMOVD
+					q.Pos = p.Pos
+					q.From.Type = obj.TYPE_REG
+					q.From.Reg = REG_R29
+					q.To.Type = obj.TYPE_MEM
+					q.To.Offset = int64(-autosize)
+					q.To.Reg = REGSP
+
+					prologueEnd = q
+
+					q = obj.Appendp(q, c.newprog)
+					q.As = AADD
+					q.Pos = p.Pos
+					q.From.Type = obj.TYPE_CONST
+					q.From.Offset = int64(-autosize)
+					q.To.Type = obj.TYPE_REG
+					q.To.Reg = REGSP
+					q.Spadj = +autosize
+
+					q = c.ctxt.EndUnsafePoint(q, c.newprog, -1)
+				}
+				prologueEnd.Pos = prologueEnd.Pos.WithXlogue(src.PosPrologueEnd)
+			} else if c.cursym.Func().Text.Mark&LEAF == 0 {
+				// A very few functions that do not return to their caller
+				// (e.g. gogo) are not identified as leaves but still have
+				// no frame.
+				c.cursym.Func().Text.Mark |= LEAF
+			}
+
+			if c.cursym.Func().Text.Mark&LEAF != 0 {
+				c.cursym.Set(obj.AttrLeaf, true)
+				break
+			}
+
+			if NeedTOCpointer(c.ctxt) {
+				q = obj.Appendp(q, c.newprog)
+				q.As = AMOVD
+				q.Pos = p.Pos
+				q.From.Type = obj.TYPE_REG
+				q.From.Reg = REG_R2
+				q.To.Type = obj.TYPE_MEM
+				q.To.Reg = REGSP
+				q.To.Offset = 24
+			}
+
+			if c.cursym.Func().Text.From.Sym.Wrapper() {
+				// if(g->panic != nil && g->panic->argp == FP) g->panic->argp = bottom-of-frame
+				//
+				//	MOVD g_panic(g), R3
+				//	CMP R0, R3
+				//	BEQ end
+				//	MOVD panic_argp(R3), R4
+				//	ADD $(autosize+8), R1, R5
+				//	CMP R4, R5
+				//	BNE end
+				//	ADD $8, R1, R6
+				//	MOVD R6, panic_argp(R3)
+				// end:
+				//	NOP
+				//
+				// The NOP is needed to give the jumps somewhere to land.
+				// It is a liblink NOP, not a ppc64 NOP: it encodes to 0 instruction bytes.
+
+				q = obj.Appendp(q, c.newprog)
+
+				q.As = AMOVD
+				q.From.Type = obj.TYPE_MEM
+				q.From.Reg = REGG
+				q.From.Offset = 4 * int64(c.ctxt.Arch.PtrSize) // G.panic
+				q.To.Type = obj.TYPE_REG
+				q.To.Reg = REG_R22
+
+				q = obj.Appendp(q, c.newprog)
+				q.As = ACMP
+				q.From.Type = obj.TYPE_REG
+				q.From.Reg = REG_R0
+				q.To.Type = obj.TYPE_REG
+				q.To.Reg = REG_R22
+
+				q = obj.Appendp(q, c.newprog)
+				q.As = ABEQ
+				q.To.Type = obj.TYPE_BRANCH
+				p1 = q
+
+				q = obj.Appendp(q, c.newprog)
+				q.As = AMOVD
+				q.From.Type = obj.TYPE_MEM
+				q.From.Reg = REG_R22
+				q.From.Offset = 0 // Panic.argp
+				q.To.Type = obj.TYPE_REG
+				q.To.Reg = REG_R23
+
+				q = obj.Appendp(q, c.newprog)
+				q.As = AADD
+				q.From.Type = obj.TYPE_CONST
+				q.From.Offset = int64(autosize) + c.ctxt.Arch.FixedFrameSize
+				q.Reg = REGSP
+				q.To.Type = obj.TYPE_REG
+				q.To.Reg = REG_R24
+
+				q = obj.Appendp(q, c.newprog)
+				q.As = ACMP
+				q.From.Type = obj.TYPE_REG
+				q.From.Reg = REG_R23
+				q.To.Type = obj.TYPE_REG
+				q.To.Reg = REG_R24
+
+				q = obj.Appendp(q, c.newprog)
+				q.As = ABNE
+				q.To.Type = obj.TYPE_BRANCH
+				p2 = q
+
+				q = obj.Appendp(q, c.newprog)
+				q.As = AADD
+				q.From.Type = obj.TYPE_CONST
+				q.From.Offset = c.ctxt.Arch.FixedFrameSize
+				q.Reg = REGSP
+				q.To.Type = obj.TYPE_REG
+				q.To.Reg = REG_R25
+
+				q = obj.Appendp(q, c.newprog)
+				q.As = AMOVD
+				q.From.Type = obj.TYPE_REG
+				q.From.Reg = REG_R25
+				q.To.Type = obj.TYPE_MEM
+				q.To.Reg = REG_R22
+				q.To.Offset = 0 // Panic.argp
+
+				q = obj.Appendp(q, c.newprog)
+
+				q.As = obj.ANOP
+				p1.To.SetTarget(q)
+				p2.To.SetTarget(q)
+			}
+
+		case obj.ARET:
+			if p.From.Type == obj.TYPE_CONST {
+				c.ctxt.Diag("using BECOME (%v) is not supported!", p)
+				break
+			}
+
+			retTarget := p.To.Sym
+
+			if c.cursym.Func().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 = c.newprog()
+				q.As = ABR
+				q.Pos = p.Pos
+				if retTarget == nil {
+					q.To.Type = obj.TYPE_REG
+					q.To.Reg = REG_LR
+				} else {
+					q.To.Type = obj.TYPE_BRANCH
+					q.To.Sym = retTarget
+				}
+				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 = c.newprog()
+			q.As = AMOVD
+			q.Pos = p.Pos
+			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 {
+				// Debug bad returns
+				q = c.newprog()
+
+				q.As = AMOVD
+				q.Pos = p.Pos
+				q.From.Type = obj.TYPE_MEM
+				q.From.Offset = 0
+				q.From.Reg = REGTMP
+				q.To.Type = obj.TYPE_REG
+				q.To.Reg = REGTMP
+
+				q.Link = p.Link
+				p.Link = q
+				p = q
+			}
+			prev := p
+			if autosize != 0 {
+				q = c.newprog()
+				q.As = AADD
+				q.Pos = p.Pos
+				q.From.Type = obj.TYPE_CONST
+				q.From.Offset = int64(autosize)
+				q.To.Type = obj.TYPE_REG
+				q.To.Reg = REGSP
+				q.Spadj = -autosize
+
+				q.Link = p.Link
+				prev.Link = q
+				prev = q
+			}
+
+			q1 = c.newprog()
+			q1.As = ABR
+			q1.Pos = p.Pos
+			if retTarget == nil {
+				q1.To.Type = obj.TYPE_REG
+				q1.To.Reg = REG_LR
+			} else {
+				q1.To.Type = obj.TYPE_BRANCH
+				q1.To.Sym = retTarget
+			}
+			q1.Mark |= BRANCH
+			q1.Spadj = +autosize
+
+			q1.Link = q.Link
+			prev.Link = q1
+		case AADD:
+			if p.To.Type == obj.TYPE_REG && p.To.Reg == REGSP && p.From.Type == obj.TYPE_CONST {
+				p.Spadj = int32(-p.From.Offset)
+			}
+		case AMOVDU:
+			if p.To.Type == obj.TYPE_MEM && p.To.Reg == REGSP {
+				p.Spadj = int32(-p.To.Offset)
+			}
+			if p.From.Type == obj.TYPE_MEM && p.From.Reg == REGSP {
+				p.Spadj = int32(-p.From.Offset)
+			}
+		case obj.AGETCALLERPC:
+			if cursym.Leaf() {
+				/* MOVD LR, Rd */
+				p.As = AMOVD
+				p.From.Type = obj.TYPE_REG
+				p.From.Reg = REG_LR
+			} else {
+				/* MOVD (RSP), Rd */
+				p.As = AMOVD
+				p.From.Type = obj.TYPE_MEM
+				p.From.Reg = REGSP
+			}
+		}
+
+		if p.To.Type == obj.TYPE_REG && p.To.Reg == REGSP && p.Spadj == 0 && p.As != ACMPU {
+			f := c.cursym.Func()
+			if f.FuncFlag&abi.FuncFlagSPWrite == 0 {
+				c.cursym.Func().FuncFlag |= abi.FuncFlagSPWrite
+				if ctxt.Debugvlog || !ctxt.IsAsm {
+					ctxt.Logf("auto-SPWRITE: %s %v\n", c.cursym.Name, p)
+					if !ctxt.IsAsm {
+						ctxt.Diag("invalid auto-SPWRITE in non-assembly")
+						ctxt.DiagFlush()
+						log.Fatalf("bad SPWRITE")
+					}
+				}
+			}
+		}
+	}
+}
+
+/*
+// instruction scheduling
+
+	if(debug['Q'] == 0)
+		return;
+
+	curtext = nil;
+	q = nil;	// p - 1
+	q1 = firstp;	// top of block
+	o = 0;		// count of instructions
+	for(p = firstp; p != nil; p = p1) {
+		p1 = p->link;
+		o++;
+		if(p->mark & NOSCHED){
+			if(q1 != p){
+				sched(q1, q);
+			}
+			for(; p != nil; p = p->link){
+				if(!(p->mark & NOSCHED))
+					break;
+				q = p;
+			}
+			p1 = p;
+			q1 = p;
+			o = 0;
+			continue;
+		}
+		if(p->mark & (LABEL|SYNC)) {
+			if(q1 != p)
+				sched(q1, q);
+			q1 = p;
+			o = 1;
+		}
+		if(p->mark & (BRANCH|SYNC)) {
+			sched(q1, p);
+			q1 = p1;
+			o = 0;
+		}
+		if(o >= NSCHED) {
+			sched(q1, p);
+			q1 = p1;
+			o = 0;
+		}
+		q = p;
+	}
+*/
+func (c *ctxt9) stacksplit(p *obj.Prog, framesize int32) *obj.Prog {
+	if c.ctxt.Flag_maymorestack != "" {
+		if c.ctxt.Flag_shared || c.ctxt.Flag_dynlink {
+			// See the call to morestack for why these are
+			// complicated to support.
+			c.ctxt.Diag("maymorestack with -shared or -dynlink is not supported")
+		}
+
+		// Spill arguments. This has to happen before we open
+		// any more frame space.
+		p = c.cursym.Func().SpillRegisterArgs(p, c.newprog)
+
+		// Save LR and REGCTXT
+		frameSize := 8 + c.ctxt.Arch.FixedFrameSize
+
+		// MOVD LR, REGTMP
+		p = obj.Appendp(p, c.newprog)
+		p.As = AMOVD
+		p.From.Type = obj.TYPE_REG
+		p.From.Reg = REG_LR
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REGTMP
+		// MOVDU REGTMP, -16(SP)
+		p = obj.Appendp(p, c.newprog)
+		p.As = AMOVDU
+		p.From.Type = obj.TYPE_REG
+		p.From.Reg = REGTMP
+		p.To.Type = obj.TYPE_MEM
+		p.To.Offset = -frameSize
+		p.To.Reg = REGSP
+		p.Spadj = int32(frameSize)
+
+		// MOVD REGCTXT, 8(SP)
+		p = obj.Appendp(p, c.newprog)
+		p.As = AMOVD
+		p.From.Type = obj.TYPE_REG
+		p.From.Reg = REGCTXT
+		p.To.Type = obj.TYPE_MEM
+		p.To.Offset = 8
+		p.To.Reg = REGSP
+
+		// BL maymorestack
+		p = obj.Appendp(p, c.newprog)
+		p.As = ABL
+		p.To.Type = obj.TYPE_BRANCH
+		// See ../x86/obj6.go
+		p.To.Sym = c.ctxt.LookupABI(c.ctxt.Flag_maymorestack, c.cursym.ABI())
+
+		// Restore LR and REGCTXT
+
+		// MOVD 8(SP), REGCTXT
+		p = obj.Appendp(p, c.newprog)
+		p.As = AMOVD
+		p.From.Type = obj.TYPE_MEM
+		p.From.Offset = 8
+		p.From.Reg = REGSP
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REGCTXT
+
+		// MOVD 0(SP), REGTMP
+		p = obj.Appendp(p, c.newprog)
+		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
+
+		// MOVD REGTMP, LR
+		p = obj.Appendp(p, c.newprog)
+		p.As = AMOVD
+		p.From.Type = obj.TYPE_REG
+		p.From.Reg = REGTMP
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REG_LR
+
+		// ADD $16, SP
+		p = obj.Appendp(p, c.newprog)
+		p.As = AADD
+		p.From.Type = obj.TYPE_CONST
+		p.From.Offset = frameSize
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REGSP
+		p.Spadj = -int32(frameSize)
+
+		// Unspill arguments.
+		p = c.cursym.Func().UnspillRegisterArgs(p, c.newprog)
+	}
+
+	// save entry point, but skipping the two instructions setting R2 in shared mode and maymorestack
+	startPred := p
+
+	// MOVD	g_stackguard(g), R22
+	p = obj.Appendp(p, c.newprog)
+
+	p.As = AMOVD
+	p.From.Type = obj.TYPE_MEM
+	p.From.Reg = REGG
+	p.From.Offset = 2 * int64(c.ctxt.Arch.PtrSize) // G.stackguard0
+	if c.cursym.CFunc() {
+		p.From.Offset = 3 * int64(c.ctxt.Arch.PtrSize) // G.stackguard1
+	}
+	p.To.Type = obj.TYPE_REG
+	p.To.Reg = REG_R22
+
+	// Mark the stack bound check and morestack call async nonpreemptible.
+	// If we get preempted here, when resumed the preemption request is
+	// cleared, but we'll still call morestack, which will double the stack
+	// unnecessarily. See issue #35470.
+	p = c.ctxt.StartUnsafePoint(p, c.newprog)
+
+	var q *obj.Prog
+	if framesize <= abi.StackSmall {
+		// small stack: SP < stackguard
+		//	CMP	stackguard, SP
+		p = obj.Appendp(p, c.newprog)
+
+		p.As = ACMPU
+		p.From.Type = obj.TYPE_REG
+		p.From.Reg = REG_R22
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REGSP
+	} else {
+		// large stack: SP-framesize < stackguard-StackSmall
+		offset := int64(framesize) - abi.StackSmall
+		if framesize > abi.StackBig {
+			// Such a large stack we need to protect against underflow.
+			// The runtime guarantees SP > objabi.StackBig, but
+			// framesize is large enough that SP-framesize may
+			// underflow, causing a direct comparison with the
+			// stack guard to incorrectly succeed. We explicitly
+			// guard against underflow.
+			//
+			//	CMPU	SP, $(framesize-StackSmall)
+			//	BLT	label-of-call-to-morestack
+			if offset <= 0xffff {
+				p = obj.Appendp(p, c.newprog)
+				p.As = ACMPU
+				p.From.Type = obj.TYPE_REG
+				p.From.Reg = REGSP
+				p.To.Type = obj.TYPE_CONST
+				p.To.Offset = offset
+			} else {
+				// Constant is too big for CMPU.
+				p = obj.Appendp(p, c.newprog)
+				p.As = AMOVD
+				p.From.Type = obj.TYPE_CONST
+				p.From.Offset = offset
+				p.To.Type = obj.TYPE_REG
+				p.To.Reg = REG_R23
+
+				p = obj.Appendp(p, c.newprog)
+				p.As = ACMPU
+				p.From.Type = obj.TYPE_REG
+				p.From.Reg = REGSP
+				p.To.Type = obj.TYPE_REG
+				p.To.Reg = REG_R23
+			}
+
+			p = obj.Appendp(p, c.newprog)
+			q = p
+			p.As = ABLT
+			p.To.Type = obj.TYPE_BRANCH
+		}
+
+		// Check against the stack guard. We've ensured this won't underflow.
+		//	ADD  $-(framesize-StackSmall), SP, R4
+		//	CMPU stackguard, R4
+		p = obj.Appendp(p, c.newprog)
+
+		p.As = AADD
+		p.From.Type = obj.TYPE_CONST
+		p.From.Offset = -offset
+		p.Reg = REGSP
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REG_R23
+
+		p = obj.Appendp(p, c.newprog)
+		p.As = ACMPU
+		p.From.Type = obj.TYPE_REG
+		p.From.Reg = REG_R22
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REG_R23
+	}
+
+	// q1: BLT	done
+	p = obj.Appendp(p, c.newprog)
+	q1 := p
+
+	p.As = ABLT
+	p.To.Type = obj.TYPE_BRANCH
+
+	p = obj.Appendp(p, c.newprog)
+	p.As = obj.ANOP // zero-width place holder
+
+	if q != nil {
+		q.To.SetTarget(p)
+	}
+
+	// Spill the register args that could be clobbered by the
+	// morestack code.
+
+	spill := c.cursym.Func().SpillRegisterArgs(p, c.newprog)
+
+	// MOVD LR, R5
+	p = obj.Appendp(spill, c.newprog)
+	p.As = AMOVD
+	p.From.Type = obj.TYPE_REG
+	p.From.Reg = REG_LR
+	p.To.Type = obj.TYPE_REG
+	p.To.Reg = REG_R5
+
+	p = c.ctxt.EmitEntryStackMap(c.cursym, p, c.newprog)
+
+	var morestacksym *obj.LSym
+	if c.cursym.CFunc() {
+		morestacksym = c.ctxt.Lookup("runtime.morestackc")
+	} else if !c.cursym.Func().Text.From.Sym.NeedCtxt() {
+		morestacksym = c.ctxt.Lookup("runtime.morestack_noctxt")
+	} else {
+		morestacksym = c.ctxt.Lookup("runtime.morestack")
+	}
+
+	if NeedTOCpointer(c.ctxt) {
+		// In PPC64 PIC code, R2 is used as TOC pointer derived from R12
+		// which is the address of function entry point when entering
+		// the function. We need to preserve R2 across call to morestack.
+		// Fortunately, in shared mode, 8(SP) and 16(SP) are reserved in
+		// the caller's frame, but not used (0(SP) is caller's saved LR,
+		// 24(SP) is caller's saved R2). Use 8(SP) to save this function's R2.
+		// MOVD R2, 8(SP)
+		p = obj.Appendp(p, c.newprog)
+		p.As = AMOVD
+		p.From.Type = obj.TYPE_REG
+		p.From.Reg = REG_R2
+		p.To.Type = obj.TYPE_MEM
+		p.To.Reg = REGSP
+		p.To.Offset = 8
+	}
+
+	if c.ctxt.Flag_dynlink {
+		// Avoid calling morestack via a PLT when dynamically linking. The
+		// PLT stubs generated by the system linker on ppc64le when "std r2,
+		// 24(r1)" to save the TOC pointer in their callers stack
+		// frame. Unfortunately (and necessarily) morestack is called before
+		// the function that calls it sets up its frame and so the PLT ends
+		// up smashing the saved TOC pointer for its caller's caller.
+		//
+		// According to the ABI documentation there is a mechanism to avoid
+		// the TOC save that the PLT stub does (put a R_PPC64_TOCSAVE
+		// relocation on the nop after the call to morestack) but at the time
+		// of writing it is not supported at all by gold and my attempt to
+		// use it with ld.bfd caused an internal linker error. So this hack
+		// seems preferable.
+
+		// MOVD $runtime.morestack(SB), R12
+		p = obj.Appendp(p, c.newprog)
+		p.As = AMOVD
+		p.From.Type = obj.TYPE_MEM
+		p.From.Sym = morestacksym
+		p.From.Name = obj.NAME_GOTREF
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REG_R12
+
+		// MOVD R12, LR
+		p = obj.Appendp(p, c.newprog)
+		p.As = AMOVD
+		p.From.Type = obj.TYPE_REG
+		p.From.Reg = REG_R12
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REG_LR
+
+		// BL LR
+		p = obj.Appendp(p, c.newprog)
+		p.As = obj.ACALL
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REG_LR
+	} else {
+		// BL	runtime.morestack(SB)
+		p = obj.Appendp(p, c.newprog)
+
+		p.As = ABL
+		p.To.Type = obj.TYPE_BRANCH
+		p.To.Sym = morestacksym
+	}
+
+	if NeedTOCpointer(c.ctxt) {
+		// MOVD 8(SP), R2
+		p = obj.Appendp(p, c.newprog)
+		p.As = AMOVD
+		p.From.Type = obj.TYPE_MEM
+		p.From.Reg = REGSP
+		p.From.Offset = 8
+		p.To.Type = obj.TYPE_REG
+		p.To.Reg = REG_R2
+	}
+
+	unspill := c.cursym.Func().UnspillRegisterArgs(p, c.newprog)
+	p = c.ctxt.EndUnsafePoint(unspill, c.newprog, -1)
+
+	// BR	start
+	p = obj.Appendp(p, c.newprog)
+	p.As = ABR
+	p.To.Type = obj.TYPE_BRANCH
+	p.To.SetTarget(startPred.Link)
+
+	// placeholder for q1's jump target
+	p = obj.Appendp(p, c.newprog)
+
+	p.As = obj.ANOP // zero-width place holder
+	q1.To.SetTarget(p)
+
+	return p
+}
+
+// MMA accumulator to/from instructions are slightly ambiguous since
+// the argument represents both source and destination, specified as
+// an accumulator. It is treated as a unary destination to simplify
+// the code generation in ppc64map.
+var unaryDst = map[obj.As]bool{
+	AXXSETACCZ: true,
+	AXXMTACC:   true,
+	AXXMFACC:   true,
+}
+
+var Linkppc64 = obj.LinkArch{
+	Arch:           sys.ArchPPC64,
+	Init:           buildop,
+	Preprocess:     preprocess,
+	Assemble:       span9,
+	Progedit:       progedit,
+	UnaryDst:       unaryDst,
+	DWARFRegisters: PPC64DWARFRegisters,
+}
+
+var Linkppc64le = obj.LinkArch{
+	Arch:           sys.ArchPPC64LE,
+	Init:           buildop,
+	Preprocess:     preprocess,
+	Assemble:       span9,
+	Progedit:       progedit,
+	UnaryDst:       unaryDst,
+	DWARFRegisters: PPC64DWARFRegisters,
+}