func span0(ctxt *obj.Link, cursym *obj.LSym) { p := cursym.Text if p == nil || p.Link == nil { // handle external functions and ELF section symbols return } ctxt.Cursym = cursym ctxt.Autosize = int32(p.To.Offset + 8) if oprange[AOR&obj.AMask] == nil { buildop(ctxt) } c := int64(0) p.Pc = c var m int var o *Optab for p = p.Link; p != nil; p = p.Link { ctxt.Curp = p p.Pc = c o = oplook(ctxt, p) m = int(o.size) if m == 0 { if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != obj.AUSEFIELD { ctxt.Diag("zero-width instruction\n%v", p) } continue } c += int64(m) } cursym.Size = c /* * if any procedure is large enough to * generate a large SBRA branch, then * generate extra passes putting branches * around jmps to fix. this is rare. */ bflag := 1 var otxt int64 var q *obj.Prog for bflag != 0 { if ctxt.Debugvlog != 0 { fmt.Fprintf(ctxt.Bso, "%5.2f span1\n", obj.Cputime()) } bflag = 0 c = 0 for p = cursym.Text.Link; p != nil; p = p.Link { p.Pc = c o = oplook(ctxt, p) // very large conditional branches if o.type_ == 6 && p.Pcond != nil { otxt = p.Pcond.Pc - c if otxt < -(1<<17)+10 || otxt >= (1<<17)-10 { q = ctxt.NewProg() q.Link = p.Link p.Link = q q.As = AJMP q.Lineno = p.Lineno q.To.Type = obj.TYPE_BRANCH q.Pcond = p.Pcond p.Pcond = q q = ctxt.NewProg() q.Link = p.Link p.Link = q q.As = AJMP q.Lineno = p.Lineno q.To.Type = obj.TYPE_BRANCH q.Pcond = q.Link.Link addnop(ctxt, p.Link) addnop(ctxt, p) bflag = 1 } } m = int(o.size) if m == 0 { if p.As != obj.ANOP && p.As != obj.AFUNCDATA && p.As != obj.APCDATA && p.As != obj.AUSEFIELD { ctxt.Diag("zero-width instruction\n%v", p) } continue } c += int64(m) } cursym.Size = c } c += -c & (FuncAlign - 1) cursym.Size = c /* * lay out the code, emitting code and data relocations. */ cursym.Grow(cursym.Size) bp := cursym.P var i int32 var out [4]uint32 for p := cursym.Text.Link; p != nil; p = p.Link { ctxt.Pc = p.Pc ctxt.Curp = p o = oplook(ctxt, p) if int(o.size) > 4*len(out) { log.Fatalf("out array in span0 is too small, need at least %d for %v", o.size/4, p) } asmout(ctxt, p, o, out[:]) for i = 0; i < int32(o.size/4); i++ { ctxt.Arch.ByteOrder.PutUint32(bp, out[i]) bp = bp[4:] } } }