diff options
Diffstat (limited to 'src/cmd/internal/obj/arm64/obj7.go')
| -rw-r--r-- | src/cmd/internal/obj/arm64/obj7.go | 307 |
1 files changed, 169 insertions, 138 deletions
diff --git a/src/cmd/internal/obj/arm64/obj7.go b/src/cmd/internal/obj/arm64/obj7.go index 0baf51973a..8f7648e5d5 100644 --- a/src/cmd/internal/obj/arm64/obj7.go +++ b/src/cmd/internal/obj/arm64/obj7.go @@ -35,6 +35,7 @@ import ( "cmd/internal/objabi" "cmd/internal/src" "cmd/internal/sys" + "log" "math" ) @@ -621,25 +622,24 @@ func preprocess(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) { prologueEnd.Pos = prologueEnd.Pos.WithXlogue(src.PosPrologueEnd) - if objabi.Framepointer_enabled { - q1 = obj.Appendp(q1, c.newprog) - q1.Pos = p.Pos - q1.As = AMOVD - q1.From.Type = obj.TYPE_REG - q1.From.Reg = REGFP - q1.To.Type = obj.TYPE_MEM - q1.To.Reg = REGSP - q1.To.Offset = -8 - - q1 = obj.Appendp(q1, c.newprog) - q1.Pos = p.Pos - q1.As = ASUB - q1.From.Type = obj.TYPE_CONST - q1.From.Offset = 8 - q1.Reg = REGSP - q1.To.Type = obj.TYPE_REG - q1.To.Reg = REGFP - } + // Frame pointer. + q1 = obj.Appendp(q1, c.newprog) + q1.Pos = p.Pos + q1.As = AMOVD + q1.From.Type = obj.TYPE_REG + q1.From.Reg = REGFP + q1.To.Type = obj.TYPE_MEM + q1.To.Reg = REGSP + q1.To.Offset = -8 + + q1 = obj.Appendp(q1, c.newprog) + q1.Pos = p.Pos + q1.As = ASUB + q1.From.Type = obj.TYPE_CONST + q1.From.Offset = 8 + q1.Reg = REGSP + q1.To.Type = obj.TYPE_REG + q1.To.Reg = REGFP if c.cursym.Func().Text.From.Sym.Wrapper() { // if(g->panic != nil && g->panic->argp == FP) g->panic->argp = bottom-of-frame @@ -764,28 +764,26 @@ func preprocess(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) { p.To.Reg = REGSP p.Spadj = -c.autosize - if objabi.Framepointer_enabled { - p = obj.Appendp(p, c.newprog) - p.As = ASUB - p.From.Type = obj.TYPE_CONST - p.From.Offset = 8 - p.Reg = REGSP - p.To.Type = obj.TYPE_REG - p.To.Reg = REGFP - } + // Frame pointer. + p = obj.Appendp(p, c.newprog) + p.As = ASUB + p.From.Type = obj.TYPE_CONST + p.From.Offset = 8 + p.Reg = REGSP + p.To.Type = obj.TYPE_REG + p.To.Reg = REGFP } } else { /* want write-back pre-indexed SP+autosize -> SP, loading REGLINK*/ - if objabi.Framepointer_enabled { - 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 = REGFP - p = obj.Appendp(p, c.newprog) - } + // Frame pointer. + 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 = REGFP + p = obj.Appendp(p, c.newprog) aoffset := c.autosize @@ -820,6 +818,28 @@ func preprocess(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) { } } + // If enabled, this code emits 'MOV PC, R27' before every 'MOV LR, PC', + // so that if you are debugging a low-level crash where PC and LR are zero, + // you can look at R27 to see what jumped to the zero. + // This is useful when bringing up Go on a new system. + // (There is similar code in ../ppc64/obj9.go:/if.false.) + const debugRETZERO = false + if debugRETZERO { + if p.As != obj.ARET { + q = newprog() + q.Pos = p.Pos + q.Link = p.Link + p.Link = q + p = q + } + p.As = AADR + p.From.Type = obj.TYPE_BRANCH + p.From.Offset = 0 + p.To.Type = obj.TYPE_REG + p.To.Reg = REGTMP + + } + if p.As != obj.ARET { q = newprog() q.Pos = p.Pos @@ -865,109 +885,120 @@ func preprocess(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) { } case obj.ADUFFCOPY: - if objabi.Framepointer_enabled { - // ADR ret_addr, R27 - // STP (FP, R27), -24(SP) - // SUB 24, SP, FP - // DUFFCOPY - // ret_addr: - // SUB 8, SP, FP - - q1 := p - // copy DUFFCOPY from q1 to q4 - q4 := obj.Appendp(p, c.newprog) - q4.Pos = p.Pos - q4.As = obj.ADUFFCOPY - q4.To = p.To - - q1.As = AADR - q1.From.Type = obj.TYPE_BRANCH - q1.To.Type = obj.TYPE_REG - q1.To.Reg = REG_R27 - - q2 := obj.Appendp(q1, c.newprog) - q2.Pos = p.Pos - q2.As = ASTP - q2.From.Type = obj.TYPE_REGREG - q2.From.Reg = REGFP - q2.From.Offset = int64(REG_R27) - q2.To.Type = obj.TYPE_MEM - q2.To.Reg = REGSP - q2.To.Offset = -24 - - // maintaine FP for DUFFCOPY - q3 := obj.Appendp(q2, c.newprog) - q3.Pos = p.Pos - q3.As = ASUB - q3.From.Type = obj.TYPE_CONST - q3.From.Offset = 24 - q3.Reg = REGSP - q3.To.Type = obj.TYPE_REG - q3.To.Reg = REGFP - - q5 := obj.Appendp(q4, c.newprog) - q5.Pos = p.Pos - q5.As = ASUB - q5.From.Type = obj.TYPE_CONST - q5.From.Offset = 8 - q5.Reg = REGSP - q5.To.Type = obj.TYPE_REG - q5.To.Reg = REGFP - q1.From.SetTarget(q5) - p = q5 - } + // ADR ret_addr, R27 + // STP (FP, R27), -24(SP) + // SUB 24, SP, FP + // DUFFCOPY + // ret_addr: + // SUB 8, SP, FP + + q1 := p + // copy DUFFCOPY from q1 to q4 + q4 := obj.Appendp(p, c.newprog) + q4.Pos = p.Pos + q4.As = obj.ADUFFCOPY + q4.To = p.To + + q1.As = AADR + q1.From.Type = obj.TYPE_BRANCH + q1.To.Type = obj.TYPE_REG + q1.To.Reg = REG_R27 + + q2 := obj.Appendp(q1, c.newprog) + q2.Pos = p.Pos + q2.As = ASTP + q2.From.Type = obj.TYPE_REGREG + q2.From.Reg = REGFP + q2.From.Offset = int64(REG_R27) + q2.To.Type = obj.TYPE_MEM + q2.To.Reg = REGSP + q2.To.Offset = -24 + + // maintain FP for DUFFCOPY + q3 := obj.Appendp(q2, c.newprog) + q3.Pos = p.Pos + q3.As = ASUB + q3.From.Type = obj.TYPE_CONST + q3.From.Offset = 24 + q3.Reg = REGSP + q3.To.Type = obj.TYPE_REG + q3.To.Reg = REGFP + + q5 := obj.Appendp(q4, c.newprog) + q5.Pos = p.Pos + q5.As = ASUB + q5.From.Type = obj.TYPE_CONST + q5.From.Offset = 8 + q5.Reg = REGSP + q5.To.Type = obj.TYPE_REG + q5.To.Reg = REGFP + q1.From.SetTarget(q5) + p = q5 case obj.ADUFFZERO: - if objabi.Framepointer_enabled { - // ADR ret_addr, R27 - // STP (FP, R27), -24(SP) - // SUB 24, SP, FP - // DUFFZERO - // ret_addr: - // SUB 8, SP, FP - - q1 := p - // copy DUFFZERO from q1 to q4 - q4 := obj.Appendp(p, c.newprog) - q4.Pos = p.Pos - q4.As = obj.ADUFFZERO - q4.To = p.To - - q1.As = AADR - q1.From.Type = obj.TYPE_BRANCH - q1.To.Type = obj.TYPE_REG - q1.To.Reg = REG_R27 - - q2 := obj.Appendp(q1, c.newprog) - q2.Pos = p.Pos - q2.As = ASTP - q2.From.Type = obj.TYPE_REGREG - q2.From.Reg = REGFP - q2.From.Offset = int64(REG_R27) - q2.To.Type = obj.TYPE_MEM - q2.To.Reg = REGSP - q2.To.Offset = -24 - - // maintaine FP for DUFFZERO - q3 := obj.Appendp(q2, c.newprog) - q3.Pos = p.Pos - q3.As = ASUB - q3.From.Type = obj.TYPE_CONST - q3.From.Offset = 24 - q3.Reg = REGSP - q3.To.Type = obj.TYPE_REG - q3.To.Reg = REGFP - - q5 := obj.Appendp(q4, c.newprog) - q5.Pos = p.Pos - q5.As = ASUB - q5.From.Type = obj.TYPE_CONST - q5.From.Offset = 8 - q5.Reg = REGSP - q5.To.Type = obj.TYPE_REG - q5.To.Reg = REGFP - q1.From.SetTarget(q5) - p = q5 + // ADR ret_addr, R27 + // STP (FP, R27), -24(SP) + // SUB 24, SP, FP + // DUFFZERO + // ret_addr: + // SUB 8, SP, FP + + q1 := p + // copy DUFFZERO from q1 to q4 + q4 := obj.Appendp(p, c.newprog) + q4.Pos = p.Pos + q4.As = obj.ADUFFZERO + q4.To = p.To + + q1.As = AADR + q1.From.Type = obj.TYPE_BRANCH + q1.To.Type = obj.TYPE_REG + q1.To.Reg = REG_R27 + + q2 := obj.Appendp(q1, c.newprog) + q2.Pos = p.Pos + q2.As = ASTP + q2.From.Type = obj.TYPE_REGREG + q2.From.Reg = REGFP + q2.From.Offset = int64(REG_R27) + q2.To.Type = obj.TYPE_MEM + q2.To.Reg = REGSP + q2.To.Offset = -24 + + // maintain FP for DUFFZERO + q3 := obj.Appendp(q2, c.newprog) + q3.Pos = p.Pos + q3.As = ASUB + q3.From.Type = obj.TYPE_CONST + q3.From.Offset = 24 + q3.Reg = REGSP + q3.To.Type = obj.TYPE_REG + q3.To.Reg = REGFP + + q5 := obj.Appendp(q4, c.newprog) + q5.Pos = p.Pos + q5.As = ASUB + q5.From.Type = obj.TYPE_CONST + q5.From.Offset = 8 + q5.Reg = REGSP + q5.To.Type = obj.TYPE_REG + q5.To.Reg = REGFP + q1.From.SetTarget(q5) + p = q5 + } + + if p.To.Type == obj.TYPE_REG && p.To.Reg == REGSP && p.Spadj == 0 { + f := c.cursym.Func() + if f.FuncFlag&objabi.FuncFlag_SPWRITE == 0 { + c.cursym.Func().FuncFlag |= objabi.FuncFlag_SPWRITE + 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") + } + } } } } |