| // 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/sys" |
| ) |
| |
| 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 |
| } |
| } |
| |
| // Put >32-bit constants in memory and load them |
| case AMOVD: |
| 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 { |
| p.From.Type = obj.TYPE_MEM |
| p.From.Sym = ctxt.Int64Sym(p.From.Offset) |
| p.From.Name = obj.NAME_EXTERN |
| p.From.Offset = 0 |
| } |
| } |
| |
| // Rewrite SUB constants into ADD. |
| switch p.As { |
| 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 |
| } |
| } |
| 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) |
| 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) |
| 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.Lookup("runtime.duffzero") |
| } else { |
| sym = c.ctxt.Lookup("runtime.duffcopy") |
| } |
| 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, |
| AECIWX, |
| AECOWX, |
| 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.Pcond |
| 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.Pcond = q |
| p2.Pcond = 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.Pcond = 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.Pcond = p0.Link |
| |
| // placeholder for q1's jump target |
| p = obj.Appendp(p, c.newprog) |
| |
| p.As = obj.ANOP // zero-width place holder |
| q1.Pcond = 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, |
| } |
