1279 lines
31 KiB
Go
1279 lines
31 KiB
Go
// cmd/9l/noop.c, cmd/9l/pass.c, cmd/9l/span.c from Vita Nuova.
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//
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// Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved.
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// Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
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// Portions Copyright © 1997-1999 Vita Nuova Limited
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// Portions Copyright © 2000-2008 Vita Nuova Holdings Limited (www.vitanuova.com)
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// Portions Copyright © 2004,2006 Bruce Ellis
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// Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
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// Revisions Copyright © 2000-2008 Lucent Technologies Inc. and others
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// Portions Copyright © 2009 The Go Authors. All rights reserved.
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//
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// Permission is hereby granted, free of charge, to any person obtaining a copy
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// of this software and associated documentation files (the "Software"), to deal
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// in the Software without restriction, including without limitation the rights
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// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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// copies of the Software, and to permit persons to whom the Software is
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// furnished to do so, subject to the following conditions:
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//
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// The above copyright notice and this permission notice shall be included in
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// all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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// THE SOFTWARE.
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package ppc64
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import (
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"github.com/twitchyliquid64/golang-asm/obj"
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"github.com/twitchyliquid64/golang-asm/objabi"
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"github.com/twitchyliquid64/golang-asm/sys"
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)
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func progedit(ctxt *obj.Link, p *obj.Prog, newprog obj.ProgAlloc) {
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p.From.Class = 0
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p.To.Class = 0
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c := ctxt9{ctxt: ctxt, newprog: newprog}
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// Rewrite BR/BL to symbol as TYPE_BRANCH.
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switch p.As {
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case ABR,
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ABL,
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obj.ARET,
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obj.ADUFFZERO,
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obj.ADUFFCOPY:
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if p.To.Sym != nil {
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p.To.Type = obj.TYPE_BRANCH
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}
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}
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// Rewrite float constants to values stored in memory.
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switch p.As {
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case AFMOVS:
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if p.From.Type == obj.TYPE_FCONST {
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f32 := float32(p.From.Val.(float64))
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p.From.Type = obj.TYPE_MEM
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p.From.Sym = ctxt.Float32Sym(f32)
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p.From.Name = obj.NAME_EXTERN
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p.From.Offset = 0
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}
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case AFMOVD:
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if p.From.Type == obj.TYPE_FCONST {
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f64 := p.From.Val.(float64)
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// Constant not needed in memory for float +/- 0
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if f64 != 0 {
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p.From.Type = obj.TYPE_MEM
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p.From.Sym = ctxt.Float64Sym(f64)
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p.From.Name = obj.NAME_EXTERN
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p.From.Offset = 0
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}
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}
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// Put >32-bit constants in memory and load them
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case AMOVD:
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if p.From.Type == obj.TYPE_CONST && p.From.Name == obj.NAME_NONE && p.From.Reg == 0 && int64(int32(p.From.Offset)) != p.From.Offset {
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p.From.Type = obj.TYPE_MEM
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p.From.Sym = ctxt.Int64Sym(p.From.Offset)
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p.From.Name = obj.NAME_EXTERN
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p.From.Offset = 0
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}
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}
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// Rewrite SUB constants into ADD.
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switch p.As {
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case ASUBC:
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if p.From.Type == obj.TYPE_CONST {
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p.From.Offset = -p.From.Offset
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p.As = AADDC
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}
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case ASUBCCC:
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if p.From.Type == obj.TYPE_CONST {
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p.From.Offset = -p.From.Offset
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p.As = AADDCCC
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}
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case ASUB:
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if p.From.Type == obj.TYPE_CONST {
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p.From.Offset = -p.From.Offset
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p.As = AADD
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}
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}
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if c.ctxt.Headtype == objabi.Haix {
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c.rewriteToUseTOC(p)
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} else if c.ctxt.Flag_dynlink {
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c.rewriteToUseGot(p)
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}
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}
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// Rewrite p, if necessary, to access a symbol using its TOC anchor.
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// This code is for AIX only.
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func (c *ctxt9) rewriteToUseTOC(p *obj.Prog) {
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if p.As == obj.ATEXT || p.As == obj.AFUNCDATA || p.As == obj.ACALL || p.As == obj.ARET || p.As == obj.AJMP {
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return
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}
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if p.As == obj.ADUFFCOPY || p.As == obj.ADUFFZERO {
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// ADUFFZERO/ADUFFCOPY is considered as an ABL except in dynamic
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// link where it should be an indirect call.
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if !c.ctxt.Flag_dynlink {
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return
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}
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// ADUFFxxx $offset
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// becomes
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// MOVD runtime.duffxxx@TOC, R12
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// ADD $offset, R12
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// MOVD R12, LR
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// BL (LR)
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var sym *obj.LSym
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if p.As == obj.ADUFFZERO {
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sym = c.ctxt.Lookup("runtime.duffzero")
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} else {
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sym = c.ctxt.Lookup("runtime.duffcopy")
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}
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// Retrieve or create the TOC anchor.
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symtoc := c.ctxt.LookupInit("TOC."+sym.Name, func(s *obj.LSym) {
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s.Type = objabi.SDATA
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s.Set(obj.AttrDuplicateOK, true)
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s.Set(obj.AttrStatic, true)
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c.ctxt.Data = append(c.ctxt.Data, s)
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s.WriteAddr(c.ctxt, 0, 8, sym, 0)
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})
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offset := p.To.Offset
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p.As = AMOVD
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p.From.Type = obj.TYPE_MEM
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p.From.Name = obj.NAME_TOCREF
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p.From.Sym = symtoc
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p.To.Type = obj.TYPE_REG
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p.To.Reg = REG_R12
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p.To.Name = obj.NAME_NONE
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p.To.Offset = 0
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p.To.Sym = nil
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p1 := obj.Appendp(p, c.newprog)
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p1.As = AADD
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p1.From.Type = obj.TYPE_CONST
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p1.From.Offset = offset
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p1.To.Type = obj.TYPE_REG
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p1.To.Reg = REG_R12
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p2 := obj.Appendp(p1, c.newprog)
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p2.As = AMOVD
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p2.From.Type = obj.TYPE_REG
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p2.From.Reg = REG_R12
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p2.To.Type = obj.TYPE_REG
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p2.To.Reg = REG_LR
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p3 := obj.Appendp(p2, c.newprog)
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p3.As = obj.ACALL
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p3.To.Type = obj.TYPE_REG
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p3.To.Reg = REG_LR
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}
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var source *obj.Addr
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if p.From.Name == obj.NAME_EXTERN || p.From.Name == obj.NAME_STATIC {
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if p.From.Type == obj.TYPE_ADDR {
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if p.As == ADWORD {
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// ADWORD $sym doesn't need TOC anchor
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return
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}
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if p.As != AMOVD {
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c.ctxt.Diag("do not know how to handle TYPE_ADDR in %v", p)
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return
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}
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if p.To.Type != obj.TYPE_REG {
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c.ctxt.Diag("do not know how to handle LEAQ-type insn to non-register in %v", p)
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return
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}
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} else if p.From.Type != obj.TYPE_MEM {
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c.ctxt.Diag("do not know how to handle %v without TYPE_MEM", p)
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return
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}
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source = &p.From
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} else if p.To.Name == obj.NAME_EXTERN || p.To.Name == obj.NAME_STATIC {
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if p.To.Type != obj.TYPE_MEM {
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c.ctxt.Diag("do not know how to handle %v without TYPE_MEM", p)
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return
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}
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if source != nil {
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c.ctxt.Diag("cannot handle symbols on both sides in %v", p)
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return
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}
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source = &p.To
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} else {
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return
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}
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if source.Sym == nil {
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c.ctxt.Diag("do not know how to handle nil symbol in %v", p)
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return
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}
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if source.Sym.Type == objabi.STLSBSS {
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return
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}
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// Retrieve or create the TOC anchor.
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symtoc := c.ctxt.LookupInit("TOC."+source.Sym.Name, func(s *obj.LSym) {
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s.Type = objabi.SDATA
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s.Set(obj.AttrDuplicateOK, true)
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s.Set(obj.AttrStatic, true)
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c.ctxt.Data = append(c.ctxt.Data, s)
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s.WriteAddr(c.ctxt, 0, 8, source.Sym, 0)
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})
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if source.Type == obj.TYPE_ADDR {
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// MOVD $sym, Rx becomes MOVD symtoc, Rx
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// MOVD $sym+<off>, Rx becomes MOVD symtoc, Rx; ADD <off>, Rx
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p.From.Type = obj.TYPE_MEM
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p.From.Sym = symtoc
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p.From.Name = obj.NAME_TOCREF
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if p.From.Offset != 0 {
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q := obj.Appendp(p, c.newprog)
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q.As = AADD
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q.From.Type = obj.TYPE_CONST
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q.From.Offset = p.From.Offset
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p.From.Offset = 0
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q.To = p.To
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}
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return
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}
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// MOVx sym, Ry becomes MOVD symtoc, REGTMP; MOVx (REGTMP), Ry
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// MOVx Ry, sym becomes MOVD symtoc, REGTMP; MOVx Ry, (REGTMP)
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// An addition may be inserted between the two MOVs if there is an offset.
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q := obj.Appendp(p, c.newprog)
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q.As = AMOVD
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q.From.Type = obj.TYPE_MEM
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q.From.Sym = symtoc
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q.From.Name = obj.NAME_TOCREF
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q.To.Type = obj.TYPE_REG
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q.To.Reg = REGTMP
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q = obj.Appendp(q, c.newprog)
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q.As = p.As
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q.From = p.From
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q.To = p.To
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if p.From.Name != obj.NAME_NONE {
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q.From.Type = obj.TYPE_MEM
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q.From.Reg = REGTMP
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q.From.Name = obj.NAME_NONE
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q.From.Sym = nil
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} else if p.To.Name != obj.NAME_NONE {
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q.To.Type = obj.TYPE_MEM
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q.To.Reg = REGTMP
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q.To.Name = obj.NAME_NONE
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q.To.Sym = nil
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} else {
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c.ctxt.Diag("unreachable case in rewriteToUseTOC with %v", p)
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}
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obj.Nopout(p)
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}
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// Rewrite p, if necessary, to access global data via the global offset table.
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func (c *ctxt9) rewriteToUseGot(p *obj.Prog) {
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if p.As == obj.ADUFFCOPY || p.As == obj.ADUFFZERO {
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// ADUFFxxx $offset
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// becomes
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// MOVD runtime.duffxxx@GOT, R12
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// ADD $offset, R12
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// MOVD R12, LR
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// BL (LR)
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var sym *obj.LSym
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if p.As == obj.ADUFFZERO {
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sym = c.ctxt.Lookup("runtime.duffzero")
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} else {
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sym = c.ctxt.Lookup("runtime.duffcopy")
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}
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offset := p.To.Offset
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p.As = AMOVD
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p.From.Type = obj.TYPE_MEM
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p.From.Name = obj.NAME_GOTREF
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p.From.Sym = sym
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p.To.Type = obj.TYPE_REG
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p.To.Reg = REG_R12
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p.To.Name = obj.NAME_NONE
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p.To.Offset = 0
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p.To.Sym = nil
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p1 := obj.Appendp(p, c.newprog)
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p1.As = AADD
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p1.From.Type = obj.TYPE_CONST
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p1.From.Offset = offset
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p1.To.Type = obj.TYPE_REG
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p1.To.Reg = REG_R12
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p2 := obj.Appendp(p1, c.newprog)
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p2.As = AMOVD
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p2.From.Type = obj.TYPE_REG
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p2.From.Reg = REG_R12
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p2.To.Type = obj.TYPE_REG
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p2.To.Reg = REG_LR
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p3 := obj.Appendp(p2, c.newprog)
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p3.As = obj.ACALL
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p3.To.Type = obj.TYPE_REG
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p3.To.Reg = REG_LR
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}
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// We only care about global data: NAME_EXTERN means a global
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// symbol in the Go sense, and p.Sym.Local is true for a few
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// internally defined symbols.
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if p.From.Type == obj.TYPE_ADDR && p.From.Name == obj.NAME_EXTERN && !p.From.Sym.Local() {
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// MOVD $sym, Rx becomes MOVD sym@GOT, Rx
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// MOVD $sym+<off>, Rx becomes MOVD sym@GOT, Rx; ADD <off>, Rx
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if p.As != AMOVD {
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c.ctxt.Diag("do not know how to handle TYPE_ADDR in %v with -dynlink", p)
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}
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if p.To.Type != obj.TYPE_REG {
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c.ctxt.Diag("do not know how to handle LEAQ-type insn to non-register in %v with -dynlink", p)
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}
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p.From.Type = obj.TYPE_MEM
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p.From.Name = obj.NAME_GOTREF
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if p.From.Offset != 0 {
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q := obj.Appendp(p, c.newprog)
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q.As = AADD
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q.From.Type = obj.TYPE_CONST
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q.From.Offset = p.From.Offset
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q.To = p.To
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p.From.Offset = 0
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}
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}
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if p.GetFrom3() != nil && p.GetFrom3().Name == obj.NAME_EXTERN {
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c.ctxt.Diag("don't know how to handle %v with -dynlink", p)
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}
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var source *obj.Addr
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// MOVx sym, Ry becomes MOVD sym@GOT, REGTMP; MOVx (REGTMP), Ry
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// MOVx Ry, sym becomes MOVD sym@GOT, REGTMP; MOVx Ry, (REGTMP)
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// An addition may be inserted between the two MOVs if there is an offset.
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if p.From.Name == obj.NAME_EXTERN && !p.From.Sym.Local() {
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if p.To.Name == obj.NAME_EXTERN && !p.To.Sym.Local() {
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c.ctxt.Diag("cannot handle NAME_EXTERN on both sides in %v with -dynlink", p)
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}
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source = &p.From
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} else if p.To.Name == obj.NAME_EXTERN && !p.To.Sym.Local() {
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source = &p.To
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} else {
|
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return
|
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}
|
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if p.As == obj.ATEXT || p.As == obj.AFUNCDATA || p.As == obj.ACALL || p.As == obj.ARET || p.As == obj.AJMP {
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return
|
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}
|
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if source.Sym.Type == objabi.STLSBSS {
|
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return
|
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}
|
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if source.Type != obj.TYPE_MEM {
|
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c.ctxt.Diag("don't know how to handle %v with -dynlink", p)
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}
|
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p1 := obj.Appendp(p, c.newprog)
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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
|
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p1.To.Reg = REGTMP
|
|
|
|
p2.As = p.As
|
|
p2.From = p.From
|
|
p2.To = p.To
|
|
if p.From.Name == obj.NAME_EXTERN {
|
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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,
|
|
AECIWX,
|
|
AECOWX,
|
|
AEIEIO,
|
|
AICBI,
|
|
AISYNC,
|
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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.FixedFrameSize())
|
|
}
|
|
|
|
if p.Mark&LEAF != 0 && autosize < objabi.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 c.ctxt.Flag_shared && c.cursym.Name != "runtime.duffzero" && c.cursym.Name != "runtime.duffcopy" {
|
|
// When compiling Go into PIC, 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
|
|
}
|
|
|
|
// Special handling of the racecall thunk. Assume that its asm code will
|
|
// save the link register and update the stack, since that code is
|
|
// called directly from C/C++ and can't clobber REGTMP (R31).
|
|
if autosize != 0 && c.cursym.Name != "runtime.racecallbackthunk" {
|
|
// 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
|
|
|
|
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
|
|
|
|
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)
|
|
|
|
}
|
|
} 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 c.ctxt.Flag_shared {
|
|
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_R3
|
|
|
|
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_R3
|
|
|
|
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_R3
|
|
q.From.Offset = 0 // Panic.argp
|
|
q.To.Type = obj.TYPE_REG
|
|
q.To.Reg = REG_R4
|
|
|
|
q = obj.Appendp(q, c.newprog)
|
|
q.As = AADD
|
|
q.From.Type = obj.TYPE_CONST
|
|
q.From.Offset = int64(autosize) + c.ctxt.FixedFrameSize()
|
|
q.Reg = REGSP
|
|
q.To.Type = obj.TYPE_REG
|
|
q.To.Reg = REG_R5
|
|
|
|
q = obj.Appendp(q, c.newprog)
|
|
q.As = ACMP
|
|
q.From.Type = obj.TYPE_REG
|
|
q.From.Reg = REG_R4
|
|
q.To.Type = obj.TYPE_REG
|
|
q.To.Reg = REG_R5
|
|
|
|
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.FixedFrameSize()
|
|
q.Reg = REGSP
|
|
q.To.Type = obj.TYPE_REG
|
|
q.To.Reg = REG_R6
|
|
|
|
q = obj.Appendp(q, c.newprog)
|
|
q.As = AMOVD
|
|
q.From.Type = obj.TYPE_REG
|
|
q.From.Reg = REG_R6
|
|
q.To.Type = obj.TYPE_MEM
|
|
q.To.Reg = REG_R3
|
|
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 || c.cursym.Name == "runtime.racecallbackthunk" {
|
|
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
|
|
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 = 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 && c.cursym.Name != "runtime.racecallbackthunk" {
|
|
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
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
// 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 {
|
|
p0 := p // save entry point, but skipping the two instructions setting R2 in shared mode
|
|
|
|
// MOVD g_stackguard(g), R3
|
|
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_R3
|
|
|
|
// 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 <= objabi.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_R3
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REGSP
|
|
} else if framesize <= objabi.StackBig {
|
|
// large stack: SP-framesize < stackguard-StackSmall
|
|
// ADD $-(framesize-StackSmall), SP, R4
|
|
// CMP stackguard, R4
|
|
p = obj.Appendp(p, c.newprog)
|
|
|
|
p.As = AADD
|
|
p.From.Type = obj.TYPE_CONST
|
|
p.From.Offset = -(int64(framesize) - objabi.StackSmall)
|
|
p.Reg = REGSP
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REG_R4
|
|
|
|
p = obj.Appendp(p, c.newprog)
|
|
p.As = ACMPU
|
|
p.From.Type = obj.TYPE_REG
|
|
p.From.Reg = REG_R3
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REG_R4
|
|
} 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.
|
|
//
|
|
// Preemption sets stackguard to StackPreempt, a very large value.
|
|
// That breaks the math above, so we have to check for that explicitly.
|
|
// // stackguard is R3
|
|
// CMP R3, $StackPreempt
|
|
// BEQ label-of-call-to-morestack
|
|
// ADD $StackGuard, SP, R4
|
|
// SUB R3, R4
|
|
// MOVD $(framesize+(StackGuard-StackSmall)), R31
|
|
// CMPU R31, R4
|
|
p = obj.Appendp(p, c.newprog)
|
|
|
|
p.As = ACMP
|
|
p.From.Type = obj.TYPE_REG
|
|
p.From.Reg = REG_R3
|
|
p.To.Type = obj.TYPE_CONST
|
|
p.To.Offset = objabi.StackPreempt
|
|
|
|
p = obj.Appendp(p, c.newprog)
|
|
q = p
|
|
p.As = ABEQ
|
|
p.To.Type = obj.TYPE_BRANCH
|
|
|
|
p = obj.Appendp(p, c.newprog)
|
|
p.As = AADD
|
|
p.From.Type = obj.TYPE_CONST
|
|
p.From.Offset = int64(objabi.StackGuard)
|
|
p.Reg = REGSP
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REG_R4
|
|
|
|
p = obj.Appendp(p, c.newprog)
|
|
p.As = ASUB
|
|
p.From.Type = obj.TYPE_REG
|
|
p.From.Reg = REG_R3
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REG_R4
|
|
|
|
p = obj.Appendp(p, c.newprog)
|
|
p.As = AMOVD
|
|
p.From.Type = obj.TYPE_CONST
|
|
p.From.Offset = int64(framesize) + int64(objabi.StackGuard) - objabi.StackSmall
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REGTMP
|
|
|
|
p = obj.Appendp(p, c.newprog)
|
|
p.As = ACMPU
|
|
p.From.Type = obj.TYPE_REG
|
|
p.From.Reg = REGTMP
|
|
p.To.Type = obj.TYPE_REG
|
|
p.To.Reg = REG_R4
|
|
}
|
|
|
|
// q1: BLT done
|
|
p = obj.Appendp(p, c.newprog)
|
|
q1 := p
|
|
|
|
p.As = ABLT
|
|
p.To.Type = obj.TYPE_BRANCH
|
|
|
|
// MOVD LR, R5
|
|
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 = REG_R5
|
|
if q != nil {
|
|
q.To.SetTarget(p)
|
|
}
|
|
|
|
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 c.ctxt.Flag_shared {
|
|
// 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 R12, 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 c.ctxt.Flag_shared {
|
|
// 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
|
|
}
|
|
|
|
p = c.ctxt.EndUnsafePoint(p, c.newprog, -1)
|
|
|
|
// BR start
|
|
p = obj.Appendp(p, c.newprog)
|
|
p.As = ABR
|
|
p.To.Type = obj.TYPE_BRANCH
|
|
p.To.SetTarget(p0.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
|
|
}
|
|
|
|
var Linkppc64 = obj.LinkArch{
|
|
Arch: sys.ArchPPC64,
|
|
Init: buildop,
|
|
Preprocess: preprocess,
|
|
Assemble: span9,
|
|
Progedit: progedit,
|
|
DWARFRegisters: PPC64DWARFRegisters,
|
|
}
|
|
|
|
var Linkppc64le = obj.LinkArch{
|
|
Arch: sys.ArchPPC64LE,
|
|
Init: buildop,
|
|
Preprocess: preprocess,
|
|
Assemble: span9,
|
|
Progedit: progedit,
|
|
DWARFRegisters: PPC64DWARFRegisters,
|
|
}
|