func zerorange(p *obj.Prog, frame int64, lo int64, hi int64) *obj.Prog { cnt := hi - lo if cnt == 0 { return p } if cnt < int64(4*gc.Widthptr) { for i := int64(0); i < cnt; i += int64(gc.Widthptr) { p = gc.Appendpp(p, arm64.AMOVD, obj.TYPE_REG, arm64.REGZERO, 0, obj.TYPE_MEM, arm64.REGSP, 8+frame+lo+i) } } else if cnt <= int64(128*gc.Widthptr) && !darwin { // darwin ld64 cannot handle BR26 reloc with non-zero addend p = gc.Appendpp(p, arm64.AMOVD, obj.TYPE_REG, arm64.REGSP, 0, obj.TYPE_REG, arm64.REGRT1, 0) p = gc.Appendpp(p, arm64.AADD, obj.TYPE_CONST, 0, 8+frame+lo-8, obj.TYPE_REG, arm64.REGRT1, 0) p.Reg = arm64.REGRT1 p = gc.Appendpp(p, obj.ADUFFZERO, obj.TYPE_NONE, 0, 0, obj.TYPE_MEM, 0, 0) gc.Naddr(&p.To, gc.Sysfunc("duffzero")) p.To.Offset = 4 * (128 - cnt/int64(gc.Widthptr)) } else { p = gc.Appendpp(p, arm64.AMOVD, obj.TYPE_CONST, 0, 8+frame+lo-8, obj.TYPE_REG, arm64.REGTMP, 0) p = gc.Appendpp(p, arm64.AMOVD, obj.TYPE_REG, arm64.REGSP, 0, obj.TYPE_REG, arm64.REGRT1, 0) p = gc.Appendpp(p, arm64.AADD, obj.TYPE_REG, arm64.REGTMP, 0, obj.TYPE_REG, arm64.REGRT1, 0) p.Reg = arm64.REGRT1 p = gc.Appendpp(p, arm64.AMOVD, obj.TYPE_CONST, 0, cnt, obj.TYPE_REG, arm64.REGTMP, 0) p = gc.Appendpp(p, arm64.AADD, obj.TYPE_REG, arm64.REGTMP, 0, obj.TYPE_REG, arm64.REGRT2, 0) p.Reg = arm64.REGRT1 p = gc.Appendpp(p, arm64.AMOVD, obj.TYPE_REG, arm64.REGZERO, 0, obj.TYPE_MEM, arm64.REGRT1, int64(gc.Widthptr)) p.Scond = arm64.C_XPRE p1 := p p = gc.Appendpp(p, arm64.ACMP, obj.TYPE_REG, arm64.REGRT1, 0, obj.TYPE_NONE, 0, 0) p.Reg = arm64.REGRT2 p = gc.Appendpp(p, arm64.ABNE, obj.TYPE_NONE, 0, 0, obj.TYPE_BRANCH, 0, 0) gc.Patch(p, p1) } return p }
// ARM64Suffix handles the special suffix for the ARM64. // It returns a boolean to indicate success; failure means // cond was unrecognized. func ARM64Suffix(prog *obj.Prog, cond string) bool { if cond == "" { return true } bits, ok := ParseARM64Suffix(cond) if !ok { return false } prog.Scond = bits return true }
// ARMConditionCodes handles the special condition code situation for the ARM. // It returns a boolean to indicate success; failure means cond was unrecognized. func ARMConditionCodes(prog *obj.Prog, cond string) bool { if cond == "" { return true } bits, ok := ParseARMCondition(cond) if !ok { return false } /* hack to make B.NE etc. work: turn it into the corresponding conditional */ if prog.As == arm.AB { prog.As = int16(bcode[(bits^arm.C_SCOND_XOR)&0xf]) bits = (bits &^ 0xf) | arm.C_SCOND_NONE } prog.Scond = bits return true }
// Called after regopt and peep have run. // Expand CHECKNIL pseudo-op into actual nil pointer check. func expandchecks(firstp *obj.Prog) { var reg int var p1 *obj.Prog for p := firstp; p != nil; p = p.Link { if p.As != obj.ACHECKNIL { continue } if gc.Debug_checknil != 0 && p.Lineno > 1 { // p->lineno==1 in generated wrappers gc.Warnl(int(p.Lineno), "generated nil check") } if p.From.Type != obj.TYPE_REG { gc.Fatalf("invalid nil check %v", p) } reg = int(p.From.Reg) // check is // CMP arg, $0 // MOV.EQ arg, 0(arg) p1 = gc.Ctxt.NewProg() gc.Clearp(p1) p1.Link = p.Link p.Link = p1 p1.Lineno = p.Lineno p1.Pc = 9999 p1.As = arm.AMOVW p1.From.Type = obj.TYPE_REG p1.From.Reg = int16(reg) p1.To.Type = obj.TYPE_MEM p1.To.Reg = int16(reg) p1.To.Offset = 0 p1.Scond = arm.C_SCOND_EQ p.As = arm.ACMP p.From.Type = obj.TYPE_CONST p.From.Reg = 0 p.From.Offset = 0 p.Reg = int16(reg) } }
func zerorange(p *obj.Prog, frame int64, lo int64, hi int64, r0 *uint32) *obj.Prog { cnt := hi - lo if cnt == 0 { return p } if *r0 == 0 { p = appendpp(p, arm.AMOVW, obj.TYPE_CONST, 0, 0, obj.TYPE_REG, arm.REG_R0, 0) *r0 = 1 } if cnt < int64(4*gc.Widthptr) { for i := int64(0); i < cnt; i += int64(gc.Widthptr) { p = appendpp(p, arm.AMOVW, obj.TYPE_REG, arm.REG_R0, 0, obj.TYPE_MEM, arm.REGSP, int32(4+frame+lo+i)) } } else if !gc.Nacl && (cnt <= int64(128*gc.Widthptr)) { p = appendpp(p, arm.AADD, obj.TYPE_CONST, 0, int32(4+frame+lo), obj.TYPE_REG, arm.REG_R1, 0) p.Reg = arm.REGSP p = appendpp(p, obj.ADUFFZERO, obj.TYPE_NONE, 0, 0, obj.TYPE_MEM, 0, 0) f := gc.Sysfunc("duffzero") gc.Naddr(&p.To, f) gc.Afunclit(&p.To, f) p.To.Offset = 4 * (128 - cnt/int64(gc.Widthptr)) } else { p = appendpp(p, arm.AADD, obj.TYPE_CONST, 0, int32(4+frame+lo), obj.TYPE_REG, arm.REG_R1, 0) p.Reg = arm.REGSP p = appendpp(p, arm.AADD, obj.TYPE_CONST, 0, int32(cnt), obj.TYPE_REG, arm.REG_R2, 0) p.Reg = arm.REG_R1 p = appendpp(p, arm.AMOVW, obj.TYPE_REG, arm.REG_R0, 0, obj.TYPE_MEM, arm.REG_R1, 4) p1 := p p.Scond |= arm.C_PBIT p = appendpp(p, arm.ACMP, obj.TYPE_REG, arm.REG_R1, 0, obj.TYPE_NONE, 0, 0) p.Reg = arm.REG_R2 p = appendpp(p, arm.ABNE, obj.TYPE_NONE, 0, 0, obj.TYPE_BRANCH, 0, 0) gc.Patch(p, p1) } return p }
func outcode(a, scond int32, g1 *obj.Addr, reg int32, g2 *obj.Addr) { var p *obj.Prog var pl *obj.Plist /* hack to make B.NE etc. work: turn it into the corresponding conditional */ if a == arm.AB { a = int32(bcode[(scond^arm.C_SCOND_XOR)&0xf]) scond = (scond &^ 0xf) | Always } if asm.Pass == 1 { goto out } p = new(obj.Prog) *p = obj.Prog{} p.Ctxt = asm.Ctxt p.As = int16(a) p.Lineno = stmtline p.Scond = uint8(scond) p.From = *g1 p.Reg = int16(reg) p.To = *g2 p.Pc = int64(asm.PC) if lastpc == nil { pl = obj.Linknewplist(asm.Ctxt) pl.Firstpc = p } else { lastpc.Link = p } lastpc = p out: if a != obj.AGLOBL && a != obj.ADATA { asm.PC++ } }
/* * block copy: * memmove(&ns, &n, w); */ func sgen(n *gc.Node, ns *gc.Node, w int64) { var res *gc.Node = ns if gc.Debug['g'] != 0 { fmt.Printf("\nsgen w=%d\n", w) gc.Dump("r", n) gc.Dump("res", ns) } if n.Ullman >= gc.UINF && ns.Ullman >= gc.UINF { gc.Fatal("sgen UINF") } if w < 0 { gc.Fatal("sgen copy %d", w) } // If copying .args, that's all the results, so record definition sites // for them for the liveness analysis. if ns.Op == gc.ONAME && ns.Sym.Name == ".args" { for l := gc.Curfn.Dcl; l != nil; l = l.Next { if l.N.Class == gc.PPARAMOUT { gc.Gvardef(l.N) } } } // Avoid taking the address for simple enough types. //if(componentgen(n, ns)) // return; if w == 0 { // evaluate side effects only. var dst gc.Node regalloc(&dst, gc.Types[gc.Tptr], nil) agen(res, &dst) agen(n, &dst) regfree(&dst) return } // determine alignment. // want to avoid unaligned access, so have to use // smaller operations for less aligned types. // for example moving [4]byte must use 4 MOVB not 1 MOVW. align := int(n.Type.Align) var op int switch align { default: gc.Fatal("sgen: invalid alignment %d for %v", align, gc.Tconv(n.Type, 0)) case 1: op = arm64.AMOVB case 2: op = arm64.AMOVH case 4: op = arm64.AMOVW case 8: op = arm64.AMOVD } if w%int64(align) != 0 { gc.Fatal("sgen: unaligned size %d (align=%d) for %v", w, align, gc.Tconv(n.Type, 0)) } c := int32(w / int64(align)) // offset on the stack osrc := int32(stkof(n)) odst := int32(stkof(res)) if osrc != -1000 && odst != -1000 && (osrc == 1000 || odst == 1000) { // osrc and odst both on stack, and at least one is in // an unknown position. Could generate code to test // for forward/backward copy, but instead just copy // to a temporary location first. var tmp gc.Node gc.Tempname(&tmp, n.Type) sgen(n, &tmp, w) sgen(&tmp, res, w) return } if osrc%int32(align) != 0 || odst%int32(align) != 0 { gc.Fatal("sgen: unaligned offset src %d or dst %d (align %d)", osrc, odst, align) } // if we are copying forward on the stack and // the src and dst overlap, then reverse direction dir := align if osrc < odst && int64(odst) < int64(osrc)+w { dir = -dir } var dst gc.Node var src gc.Node if n.Ullman >= res.Ullman { agenr(n, &dst, res) // temporarily use dst regalloc(&src, gc.Types[gc.Tptr], nil) gins(arm64.AMOVD, &dst, &src) if res.Op == gc.ONAME { gc.Gvardef(res) } agen(res, &dst) } else { if res.Op == gc.ONAME { gc.Gvardef(res) } agenr(res, &dst, res) agenr(n, &src, nil) } var tmp gc.Node regalloc(&tmp, gc.Types[gc.Tptr], nil) // set up end marker var nend gc.Node // move src and dest to the end of block if necessary if dir < 0 { if c >= 4 { regalloc(&nend, gc.Types[gc.Tptr], nil) gins(arm64.AMOVD, &src, &nend) } p := gins(arm64.AADD, nil, &src) p.From.Type = obj.TYPE_CONST p.From.Offset = w p = gins(arm64.AADD, nil, &dst) p.From.Type = obj.TYPE_CONST p.From.Offset = w } else { p := gins(arm64.AADD, nil, &src) p.From.Type = obj.TYPE_CONST p.From.Offset = int64(-dir) p = gins(arm64.AADD, nil, &dst) p.From.Type = obj.TYPE_CONST p.From.Offset = int64(-dir) if c >= 4 { regalloc(&nend, gc.Types[gc.Tptr], nil) p := gins(arm64.AMOVD, &src, &nend) p.From.Type = obj.TYPE_ADDR p.From.Offset = w } } // move // TODO: enable duffcopy for larger copies. if c >= 4 { p := gins(op, &src, &tmp) p.From.Type = obj.TYPE_MEM p.From.Offset = int64(dir) p.Scond = arm64.C_XPRE ploop := p p = gins(op, &tmp, &dst) p.To.Type = obj.TYPE_MEM p.To.Offset = int64(dir) p.Scond = arm64.C_XPRE p = gcmp(arm64.ACMP, &src, &nend) gc.Patch(gc.Gbranch(arm64.ABNE, nil, 0), ploop) regfree(&nend) } else { // TODO(austin): Instead of generating ADD $-8,R8; ADD // $-8,R7; n*(MOVDU 8(R8),R9; MOVDU R9,8(R7);) just // generate the offsets directly and eliminate the // ADDs. That will produce shorter, more // pipeline-able code. var p *obj.Prog for { tmp14 := c c-- if tmp14 <= 0 { break } p = gins(op, &src, &tmp) p.From.Type = obj.TYPE_MEM p.From.Offset = int64(dir) p.Scond = arm64.C_XPRE p = gins(op, &tmp, &dst) p.To.Type = obj.TYPE_MEM p.To.Offset = int64(dir) p.Scond = arm64.C_XPRE } } regfree(&dst) regfree(&src) regfree(&tmp) }
func clearfat(nl *gc.Node) { /* clear a fat object */ if gc.Debug['g'] != 0 { gc.Dump("\nclearfat", nl) } w := uint32(nl.Type.Width) // Avoid taking the address for simple enough types. if gc.Componentgen(nil, nl) { return } c := w % 4 // bytes q := w / 4 // quads var r0 gc.Node r0.Op = gc.OREGISTER r0.Reg = arm.REG_R0 var r1 gc.Node r1.Op = gc.OREGISTER r1.Reg = arm.REG_R1 var dst gc.Node gc.Regalloc(&dst, gc.Types[gc.Tptr], &r1) gc.Agen(nl, &dst) var nc gc.Node gc.Nodconst(&nc, gc.Types[gc.TUINT32], 0) var nz gc.Node gc.Regalloc(&nz, gc.Types[gc.TUINT32], &r0) gc.Cgen(&nc, &nz) if q > 128 { var end gc.Node gc.Regalloc(&end, gc.Types[gc.Tptr], nil) p := gins(arm.AMOVW, &dst, &end) p.From.Type = obj.TYPE_ADDR p.From.Offset = int64(q) * 4 p = gins(arm.AMOVW, &nz, &dst) p.To.Type = obj.TYPE_MEM p.To.Offset = 4 p.Scond |= arm.C_PBIT pl := p p = gins(arm.ACMP, &dst, nil) raddr(&end, p) gc.Patch(gc.Gbranch(arm.ABNE, nil, 0), pl) gc.Regfree(&end) } else if q >= 4 && !gc.Nacl { f := gc.Sysfunc("duffzero") p := gins(obj.ADUFFZERO, nil, f) gc.Afunclit(&p.To, f) // 4 and 128 = magic constants: see ../../runtime/asm_arm.s p.To.Offset = 4 * (128 - int64(q)) } else { var p *obj.Prog for q > 0 { p = gins(arm.AMOVW, &nz, &dst) p.To.Type = obj.TYPE_MEM p.To.Offset = 4 p.Scond |= arm.C_PBIT //print("1. %v\n", p); q-- } } var p *obj.Prog for c > 0 { p = gins(arm.AMOVB, &nz, &dst) p.To.Type = obj.TYPE_MEM p.To.Offset = 1 p.Scond |= arm.C_PBIT //print("2. %v\n", p); c-- } gc.Regfree(&dst) gc.Regfree(&nz) }
/* * generate shift according to op, one of: * res = nl << nr * res = nl >> nr */ func cgen_shift(op int, bounded bool, nl *gc.Node, nr *gc.Node, res *gc.Node) { if nl.Type.Width > 4 { gc.Fatalf("cgen_shift %v", nl.Type) } w := int(nl.Type.Width * 8) if op == gc.OLROT { v := nr.Int() var n1 gc.Node gc.Regalloc(&n1, nl.Type, res) if w == 32 { gc.Cgen(nl, &n1) gshift(arm.AMOVW, &n1, arm.SHIFT_RR, int32(w)-int32(v), &n1) } else { var n2 gc.Node gc.Regalloc(&n2, nl.Type, nil) gc.Cgen(nl, &n2) gshift(arm.AMOVW, &n2, arm.SHIFT_LL, int32(v), &n1) gshift(arm.AORR, &n2, arm.SHIFT_LR, int32(w)-int32(v), &n1) gc.Regfree(&n2) // Ensure sign/zero-extended result. gins(optoas(gc.OAS, nl.Type), &n1, &n1) } gmove(&n1, res) gc.Regfree(&n1) return } if nr.Op == gc.OLITERAL { var n1 gc.Node gc.Regalloc(&n1, nl.Type, res) gc.Cgen(nl, &n1) sc := uint64(nr.Int()) if sc == 0 { } else // nothing to do if sc >= uint64(nl.Type.Width*8) { if op == gc.ORSH && gc.Issigned[nl.Type.Etype] { gshift(arm.AMOVW, &n1, arm.SHIFT_AR, int32(w), &n1) } else { gins(arm.AEOR, &n1, &n1) } } else { if op == gc.ORSH && gc.Issigned[nl.Type.Etype] { gshift(arm.AMOVW, &n1, arm.SHIFT_AR, int32(sc), &n1) } else if op == gc.ORSH { gshift(arm.AMOVW, &n1, arm.SHIFT_LR, int32(sc), &n1) // OLSH } else { gshift(arm.AMOVW, &n1, arm.SHIFT_LL, int32(sc), &n1) } } if w < 32 && op == gc.OLSH { gins(optoas(gc.OAS, nl.Type), &n1, &n1) } gmove(&n1, res) gc.Regfree(&n1) return } tr := nr.Type var t gc.Node var n1 gc.Node var n2 gc.Node var n3 gc.Node if tr.Width > 4 { var nt gc.Node gc.Tempname(&nt, nr.Type) if nl.Ullman >= nr.Ullman { gc.Regalloc(&n2, nl.Type, res) gc.Cgen(nl, &n2) gc.Cgen(nr, &nt) n1 = nt } else { gc.Cgen(nr, &nt) gc.Regalloc(&n2, nl.Type, res) gc.Cgen(nl, &n2) } var hi gc.Node var lo gc.Node split64(&nt, &lo, &hi) gc.Regalloc(&n1, gc.Types[gc.TUINT32], nil) gc.Regalloc(&n3, gc.Types[gc.TUINT32], nil) gmove(&lo, &n1) gmove(&hi, &n3) splitclean() gins(arm.ATST, &n3, nil) gc.Nodconst(&t, gc.Types[gc.TUINT32], int64(w)) p1 := gins(arm.AMOVW, &t, &n1) p1.Scond = arm.C_SCOND_NE tr = gc.Types[gc.TUINT32] gc.Regfree(&n3) } else { if nl.Ullman >= nr.Ullman { gc.Regalloc(&n2, nl.Type, res) gc.Cgen(nl, &n2) gc.Regalloc(&n1, nr.Type, nil) gc.Cgen(nr, &n1) } else { gc.Regalloc(&n1, nr.Type, nil) gc.Cgen(nr, &n1) gc.Regalloc(&n2, nl.Type, res) gc.Cgen(nl, &n2) } } // test for shift being 0 gins(arm.ATST, &n1, nil) p3 := gc.Gbranch(arm.ABEQ, nil, -1) // test and fix up large shifts // TODO: if(!bounded), don't emit some of this. gc.Regalloc(&n3, tr, nil) gc.Nodconst(&t, gc.Types[gc.TUINT32], int64(w)) gmove(&t, &n3) gins(arm.ACMP, &n1, &n3) if op == gc.ORSH { var p1 *obj.Prog var p2 *obj.Prog if gc.Issigned[nl.Type.Etype] { p1 = gshift(arm.AMOVW, &n2, arm.SHIFT_AR, int32(w)-1, &n2) p2 = gregshift(arm.AMOVW, &n2, arm.SHIFT_AR, &n1, &n2) } else { p1 = gins(arm.AEOR, &n2, &n2) p2 = gregshift(arm.AMOVW, &n2, arm.SHIFT_LR, &n1, &n2) } p1.Scond = arm.C_SCOND_HS p2.Scond = arm.C_SCOND_LO } else { p1 := gins(arm.AEOR, &n2, &n2) p2 := gregshift(arm.AMOVW, &n2, arm.SHIFT_LL, &n1, &n2) p1.Scond = arm.C_SCOND_HS p2.Scond = arm.C_SCOND_LO } gc.Regfree(&n3) gc.Patch(p3, gc.Pc) // Left-shift of smaller word must be sign/zero-extended. if w < 32 && op == gc.OLSH { gins(optoas(gc.OAS, nl.Type), &n2, &n2) } gmove(&n2, res) gc.Regfree(&n1) gc.Regfree(&n2) }
func stacksplit(ctxt *obj.Link, p *obj.Prog, framesize int32) *obj.Prog { // MOVW g_stackguard(g), R1 p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_MEM p.From.Reg = REGG p.From.Offset = 2 * int64(ctxt.Arch.Ptrsize) // G.stackguard0 if ctxt.Cursym.Cfunc != 0 { p.From.Offset = 3 * int64(ctxt.Arch.Ptrsize) // G.stackguard1 } p.To.Type = obj.TYPE_REG p.To.Reg = REG_R1 if framesize <= obj.StackSmall { // small stack: SP < stackguard // CMP stackguard, SP p = obj.Appendp(ctxt, p) p.As = ACMP p.From.Type = obj.TYPE_REG p.From.Reg = REG_R1 p.Reg = REGSP } else if framesize <= obj.StackBig { // large stack: SP-framesize < stackguard-StackSmall // MOVW $-framesize(SP), R2 // CMP stackguard, R2 p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_ADDR p.From.Reg = REGSP p.From.Offset = int64(-framesize) p.To.Type = obj.TYPE_REG p.To.Reg = REG_R2 p = obj.Appendp(ctxt, p) p.As = ACMP p.From.Type = obj.TYPE_REG p.From.Reg = REG_R1 p.Reg = REG_R2 } 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. // CMP $StackPreempt, R1 // MOVW.NE $StackGuard(SP), R2 // SUB.NE R1, R2 // MOVW.NE $(framesize+(StackGuard-StackSmall)), R3 // CMP.NE R3, R2 p = obj.Appendp(ctxt, p) p.As = ACMP p.From.Type = obj.TYPE_CONST p.From.Offset = int64(uint32(obj.StackPreempt & (1<<32 - 1))) p.Reg = REG_R1 p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_ADDR p.From.Reg = REGSP p.From.Offset = obj.StackGuard p.To.Type = obj.TYPE_REG p.To.Reg = REG_R2 p.Scond = C_SCOND_NE p = obj.Appendp(ctxt, p) p.As = ASUB p.From.Type = obj.TYPE_REG p.From.Reg = REG_R1 p.To.Type = obj.TYPE_REG p.To.Reg = REG_R2 p.Scond = C_SCOND_NE p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_ADDR p.From.Offset = int64(framesize) + (obj.StackGuard - obj.StackSmall) p.To.Type = obj.TYPE_REG p.To.Reg = REG_R3 p.Scond = C_SCOND_NE p = obj.Appendp(ctxt, p) p.As = ACMP p.From.Type = obj.TYPE_REG p.From.Reg = REG_R3 p.Reg = REG_R2 p.Scond = C_SCOND_NE } // BLS call-to-morestack bls := obj.Appendp(ctxt, p) bls.As = ABLS bls.To.Type = obj.TYPE_BRANCH var last *obj.Prog for last = ctxt.Cursym.Text; last.Link != nil; last = last.Link { } // MOVW LR, R3 movw := obj.Appendp(ctxt, last) movw.As = AMOVW movw.From.Type = obj.TYPE_REG movw.From.Reg = REGLINK movw.To.Type = obj.TYPE_REG movw.To.Reg = REG_R3 bls.Pcond = movw // BL runtime.morestack call := obj.Appendp(ctxt, movw) call.As = obj.ACALL call.To.Type = obj.TYPE_BRANCH morestack := "runtime.morestack" switch { case ctxt.Cursym.Cfunc != 0: morestack = "runtime.morestackc" case ctxt.Cursym.Text.From3.Offset&obj.NEEDCTXT == 0: morestack = "runtime.morestack_noctxt" } call.To.Sym = obj.Linklookup(ctxt, morestack, 0) // B start b := obj.Appendp(ctxt, call) b.As = obj.AJMP b.To.Type = obj.TYPE_BRANCH b.Pcond = ctxt.Cursym.Text.Link return bls }
func blockcopy(n, res *gc.Node, osrc, odst, w int64) { // determine alignment. // want to avoid unaligned access, so have to use // smaller operations for less aligned types. // for example moving [4]byte must use 4 MOVB not 1 MOVW. align := int(n.Type.Align) var op obj.As switch align { default: gc.Fatalf("sgen: invalid alignment %d for %v", align, n.Type) case 1: op = arm64.AMOVB case 2: op = arm64.AMOVH case 4: op = arm64.AMOVW case 8: op = arm64.AMOVD } if w%int64(align) != 0 { gc.Fatalf("sgen: unaligned size %d (align=%d) for %v", w, align, n.Type) } c := int32(w / int64(align)) if osrc%int64(align) != 0 || odst%int64(align) != 0 { gc.Fatalf("sgen: unaligned offset src %d or dst %d (align %d)", osrc, odst, align) } // if we are copying forward on the stack and // the src and dst overlap, then reverse direction dir := align if osrc < odst && odst < osrc+w { dir = -dir } var dst gc.Node var src gc.Node if n.Ullman >= res.Ullman { gc.Agenr(n, &dst, res) // temporarily use dst gc.Regalloc(&src, gc.Types[gc.Tptr], nil) gins(arm64.AMOVD, &dst, &src) if res.Op == gc.ONAME { gc.Gvardef(res) } gc.Agen(res, &dst) } else { if res.Op == gc.ONAME { gc.Gvardef(res) } gc.Agenr(res, &dst, res) gc.Agenr(n, &src, nil) } var tmp gc.Node gc.Regalloc(&tmp, gc.Types[gc.Tptr], nil) // set up end marker var nend gc.Node // move src and dest to the end of block if necessary if dir < 0 { if c >= 4 { gc.Regalloc(&nend, gc.Types[gc.Tptr], nil) gins(arm64.AMOVD, &src, &nend) } p := gins(arm64.AADD, nil, &src) p.From.Type = obj.TYPE_CONST p.From.Offset = w p = gins(arm64.AADD, nil, &dst) p.From.Type = obj.TYPE_CONST p.From.Offset = w } else { p := gins(arm64.AADD, nil, &src) p.From.Type = obj.TYPE_CONST p.From.Offset = int64(-dir) p = gins(arm64.AADD, nil, &dst) p.From.Type = obj.TYPE_CONST p.From.Offset = int64(-dir) if c >= 4 { gc.Regalloc(&nend, gc.Types[gc.Tptr], nil) p := gins(arm64.AMOVD, &src, &nend) p.From.Type = obj.TYPE_ADDR p.From.Offset = w } } // move // TODO: enable duffcopy for larger copies. if c >= 4 { p := gins(op, &src, &tmp) p.From.Type = obj.TYPE_MEM p.From.Offset = int64(dir) p.Scond = arm64.C_XPRE ploop := p p = gins(op, &tmp, &dst) p.To.Type = obj.TYPE_MEM p.To.Offset = int64(dir) p.Scond = arm64.C_XPRE p = gcmp(arm64.ACMP, &src, &nend) gc.Patch(gc.Gbranch(arm64.ABNE, nil, 0), ploop) gc.Regfree(&nend) } else { // TODO(austin): Instead of generating ADD $-8,R8; ADD // $-8,R7; n*(MOVDU 8(R8),R9; MOVDU R9,8(R7);) just // generate the offsets directly and eliminate the // ADDs. That will produce shorter, more // pipeline-able code. var p *obj.Prog for ; c > 0; c-- { p = gins(op, &src, &tmp) p.From.Type = obj.TYPE_MEM p.From.Offset = int64(dir) p.Scond = arm64.C_XPRE p = gins(op, &tmp, &dst) p.To.Type = obj.TYPE_MEM p.To.Offset = int64(dir) p.Scond = arm64.C_XPRE } } gc.Regfree(&dst) gc.Regfree(&src) gc.Regfree(&tmp) }
/* * block copy: * memmove(&res, &n, w); * NB: character copy assumed little endian architecture */ func sgen(n *gc.Node, res *gc.Node, w int64) { if gc.Debug['g'] != 0 { fmt.Printf("\nsgen w=%d\n", w) gc.Dump("r", n) gc.Dump("res", res) } if n.Ullman >= gc.UINF && res.Ullman >= gc.UINF { gc.Fatal("sgen UINF") } if w < 0 || int64(int32(w)) != w { gc.Fatal("sgen copy %d", w) } if n.Type == nil { gc.Fatal("sgen: missing type") } if w == 0 { // evaluate side effects only. var dst gc.Node regalloc(&dst, gc.Types[gc.Tptr], nil) agen(res, &dst) agen(n, &dst) regfree(&dst) return } // If copying .args, that's all the results, so record definition sites // for them for the liveness analysis. if res.Op == gc.ONAME && res.Sym.Name == ".args" { for l := gc.Curfn.Dcl; l != nil; l = l.Next { if l.N.Class == gc.PPARAMOUT { gc.Gvardef(l.N) } } } // Avoid taking the address for simple enough types. if componentgen(n, res) { return } // determine alignment. // want to avoid unaligned access, so have to use // smaller operations for less aligned types. // for example moving [4]byte must use 4 MOVB not 1 MOVW. align := int(n.Type.Align) var op int switch align { default: gc.Fatal("sgen: invalid alignment %d for %v", align, gc.Tconv(n.Type, 0)) case 1: op = arm.AMOVB case 2: op = arm.AMOVH case 4: op = arm.AMOVW } if w%int64(align) != 0 { gc.Fatal("sgen: unaligned size %d (align=%d) for %v", w, align, gc.Tconv(n.Type, 0)) } c := int32(w / int64(align)) // offset on the stack osrc := stkof(n) odst := stkof(res) if osrc != -1000 && odst != -1000 && (osrc == 1000 || odst == 1000) { // osrc and odst both on stack, and at least one is in // an unknown position. Could generate code to test // for forward/backward copy, but instead just copy // to a temporary location first. var tmp gc.Node gc.Tempname(&tmp, n.Type) sgen(n, &tmp, w) sgen(&tmp, res, w) return } if osrc%int32(align) != 0 || odst%int32(align) != 0 { gc.Fatal("sgen: unaligned offset src %d or dst %d (align %d)", osrc, odst, align) } // if we are copying forward on the stack and // the src and dst overlap, then reverse direction dir := align if osrc < odst && int64(odst) < int64(osrc)+w { dir = -dir } if op == arm.AMOVW && !gc.Nacl && dir > 0 && c >= 4 && c <= 128 { var r0 gc.Node r0.Op = gc.OREGISTER r0.Val.U.Reg = REGALLOC_R0 var r1 gc.Node r1.Op = gc.OREGISTER r1.Val.U.Reg = REGALLOC_R0 + 1 var r2 gc.Node r2.Op = gc.OREGISTER r2.Val.U.Reg = REGALLOC_R0 + 2 var src gc.Node regalloc(&src, gc.Types[gc.Tptr], &r1) var dst gc.Node regalloc(&dst, gc.Types[gc.Tptr], &r2) if n.Ullman >= res.Ullman { // eval n first agen(n, &src) if res.Op == gc.ONAME { gc.Gvardef(res) } agen(res, &dst) } else { // eval res first if res.Op == gc.ONAME { gc.Gvardef(res) } agen(res, &dst) agen(n, &src) } var tmp gc.Node regalloc(&tmp, gc.Types[gc.Tptr], &r0) f := gc.Sysfunc("duffcopy") p := gins(obj.ADUFFCOPY, nil, f) gc.Afunclit(&p.To, f) // 8 and 128 = magic constants: see ../../runtime/asm_arm.s p.To.Offset = 8 * (128 - int64(c)) regfree(&tmp) regfree(&src) regfree(&dst) return } var dst gc.Node var src gc.Node if n.Ullman >= res.Ullman { agenr(n, &dst, res) // temporarily use dst regalloc(&src, gc.Types[gc.Tptr], nil) gins(arm.AMOVW, &dst, &src) if res.Op == gc.ONAME { gc.Gvardef(res) } agen(res, &dst) } else { if res.Op == gc.ONAME { gc.Gvardef(res) } agenr(res, &dst, res) agenr(n, &src, nil) } var tmp gc.Node regalloc(&tmp, gc.Types[gc.TUINT32], nil) // set up end marker var nend gc.Node if c >= 4 { regalloc(&nend, gc.Types[gc.TUINT32], nil) p := gins(arm.AMOVW, &src, &nend) p.From.Type = obj.TYPE_ADDR if dir < 0 { p.From.Offset = int64(dir) } else { p.From.Offset = w } } // move src and dest to the end of block if necessary if dir < 0 { p := gins(arm.AMOVW, &src, &src) p.From.Type = obj.TYPE_ADDR p.From.Offset = w + int64(dir) p = gins(arm.AMOVW, &dst, &dst) p.From.Type = obj.TYPE_ADDR p.From.Offset = w + int64(dir) } // move if c >= 4 { p := gins(op, &src, &tmp) p.From.Type = obj.TYPE_MEM p.From.Offset = int64(dir) p.Scond |= arm.C_PBIT ploop := p p = gins(op, &tmp, &dst) p.To.Type = obj.TYPE_MEM p.To.Offset = int64(dir) p.Scond |= arm.C_PBIT p = gins(arm.ACMP, &src, nil) raddr(&nend, p) gc.Patch(gc.Gbranch(arm.ABNE, nil, 0), ploop) regfree(&nend) } else { var p *obj.Prog for { tmp14 := c c-- if tmp14 <= 0 { break } p = gins(op, &src, &tmp) p.From.Type = obj.TYPE_MEM p.From.Offset = int64(dir) p.Scond |= arm.C_PBIT p = gins(op, &tmp, &dst) p.To.Type = obj.TYPE_MEM p.To.Offset = int64(dir) p.Scond |= arm.C_PBIT } } regfree(&dst) regfree(&src) regfree(&tmp) }
func stacksplit(ctxt *obj.Link, p *obj.Prog, framesize int32) *obj.Prog { // MOVW g_stackguard(g), R1 p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_MEM p.From.Reg = REGG p.From.Offset = 2 * int64(ctxt.Arch.PtrSize) // G.stackguard0 if ctxt.Cursym.CFunc() { p.From.Offset = 3 * int64(ctxt.Arch.PtrSize) // G.stackguard1 } p.To.Type = obj.TYPE_REG p.To.Reg = REG_R1 if framesize <= obj.StackSmall { // small stack: SP < stackguard // CMP stackguard, SP p = obj.Appendp(ctxt, p) p.As = ACMP p.From.Type = obj.TYPE_REG p.From.Reg = REG_R1 p.Reg = REGSP } else if framesize <= obj.StackBig { // large stack: SP-framesize < stackguard-StackSmall // MOVW $-framesize(SP), R2 // CMP stackguard, R2 p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_ADDR p.From.Reg = REGSP p.From.Offset = int64(-framesize) p.To.Type = obj.TYPE_REG p.To.Reg = REG_R2 p = obj.Appendp(ctxt, p) p.As = ACMP p.From.Type = obj.TYPE_REG p.From.Reg = REG_R1 p.Reg = REG_R2 } 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. // CMP $StackPreempt, R1 // MOVW.NE $StackGuard(SP), R2 // SUB.NE R1, R2 // MOVW.NE $(framesize+(StackGuard-StackSmall)), R3 // CMP.NE R3, R2 p = obj.Appendp(ctxt, p) p.As = ACMP p.From.Type = obj.TYPE_CONST p.From.Offset = int64(uint32(obj.StackPreempt & (1<<32 - 1))) p.Reg = REG_R1 p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_ADDR p.From.Reg = REGSP p.From.Offset = obj.StackGuard p.To.Type = obj.TYPE_REG p.To.Reg = REG_R2 p.Scond = C_SCOND_NE p = obj.Appendp(ctxt, p) p.As = ASUB p.From.Type = obj.TYPE_REG p.From.Reg = REG_R1 p.To.Type = obj.TYPE_REG p.To.Reg = REG_R2 p.Scond = C_SCOND_NE p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_ADDR p.From.Offset = int64(framesize) + (obj.StackGuard - obj.StackSmall) p.To.Type = obj.TYPE_REG p.To.Reg = REG_R3 p.Scond = C_SCOND_NE p = obj.Appendp(ctxt, p) p.As = ACMP p.From.Type = obj.TYPE_REG p.From.Reg = REG_R3 p.Reg = REG_R2 p.Scond = C_SCOND_NE } // BLS call-to-morestack bls := obj.Appendp(ctxt, p) bls.As = ABLS bls.To.Type = obj.TYPE_BRANCH var last *obj.Prog for last = ctxt.Cursym.Text; last.Link != nil; last = last.Link { } // Now we are at the end of the function, but logically // we are still in function prologue. We need to fix the // SP data and PCDATA. spfix := obj.Appendp(ctxt, last) spfix.As = obj.ANOP spfix.Spadj = -framesize pcdata := obj.Appendp(ctxt, spfix) pcdata.Lineno = ctxt.Cursym.Text.Lineno pcdata.Mode = ctxt.Cursym.Text.Mode pcdata.As = obj.APCDATA pcdata.From.Type = obj.TYPE_CONST pcdata.From.Offset = obj.PCDATA_StackMapIndex pcdata.To.Type = obj.TYPE_CONST pcdata.To.Offset = -1 // pcdata starts at -1 at function entry // MOVW LR, R3 movw := obj.Appendp(ctxt, pcdata) movw.As = AMOVW movw.From.Type = obj.TYPE_REG movw.From.Reg = REGLINK movw.To.Type = obj.TYPE_REG movw.To.Reg = REG_R3 bls.Pcond = movw // BL runtime.morestack call := obj.Appendp(ctxt, movw) call.As = obj.ACALL call.To.Type = obj.TYPE_BRANCH morestack := "runtime.morestack" switch { case ctxt.Cursym.CFunc(): morestack = "runtime.morestackc" case ctxt.Cursym.Text.From3.Offset&obj.NEEDCTXT == 0: morestack = "runtime.morestack_noctxt" } call.To.Sym = obj.Linklookup(ctxt, morestack, 0) // B start b := obj.Appendp(ctxt, call) b.As = obj.AJMP b.To.Type = obj.TYPE_BRANCH b.Pcond = ctxt.Cursym.Text.Link b.Spadj = +framesize return bls }
func stacksplit(ctxt *obj.Link, p *obj.Prog, framesize int32, noctxt bool) *obj.Prog { // MOVW g_stackguard(g), R1 p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_MEM p.From.Reg = REGG p.From.Offset = 2 * int64(ctxt.Arch.Ptrsize) // G.stackguard0 if ctxt.Cursym.Cfunc != 0 { p.From.Offset = 3 * int64(ctxt.Arch.Ptrsize) // G.stackguard1 } p.To.Type = obj.TYPE_REG p.To.Reg = REG_R1 if framesize <= obj.StackSmall { // small stack: SP < stackguard // CMP stackguard, SP p = obj.Appendp(ctxt, p) p.As = ACMP p.From.Type = obj.TYPE_REG p.From.Reg = REG_R1 p.Reg = REGSP } else if framesize <= obj.StackBig { // large stack: SP-framesize < stackguard-StackSmall // MOVW $-framesize(SP), R2 // CMP stackguard, R2 p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_ADDR p.From.Reg = REGSP p.From.Offset = int64(-framesize) p.To.Type = obj.TYPE_REG p.To.Reg = REG_R2 p = obj.Appendp(ctxt, p) p.As = ACMP p.From.Type = obj.TYPE_REG p.From.Reg = REG_R1 p.Reg = REG_R2 } 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. // CMP $StackPreempt, R1 // MOVW.NE $StackGuard(SP), R2 // SUB.NE R1, R2 // MOVW.NE $(framesize+(StackGuard-StackSmall)), R3 // CMP.NE R3, R2 p = obj.Appendp(ctxt, p) p.As = ACMP p.From.Type = obj.TYPE_CONST p.From.Offset = int64(uint32(obj.StackPreempt & (1<<32 - 1))) p.Reg = REG_R1 p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_ADDR p.From.Reg = REGSP p.From.Offset = obj.StackGuard p.To.Type = obj.TYPE_REG p.To.Reg = REG_R2 p.Scond = C_SCOND_NE p = obj.Appendp(ctxt, p) p.As = ASUB p.From.Type = obj.TYPE_REG p.From.Reg = REG_R1 p.To.Type = obj.TYPE_REG p.To.Reg = REG_R2 p.Scond = C_SCOND_NE p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_ADDR p.From.Offset = int64(framesize) + (obj.StackGuard - obj.StackSmall) p.To.Type = obj.TYPE_REG p.To.Reg = REG_R3 p.Scond = C_SCOND_NE p = obj.Appendp(ctxt, p) p.As = ACMP p.From.Type = obj.TYPE_REG p.From.Reg = REG_R3 p.Reg = REG_R2 p.Scond = C_SCOND_NE } // MOVW.LS R14, R3 p = obj.Appendp(ctxt, p) p.As = AMOVW p.Scond = C_SCOND_LS p.From.Type = obj.TYPE_REG p.From.Reg = REGLINK p.To.Type = obj.TYPE_REG p.To.Reg = REG_R3 // BL.LS runtime.morestack(SB) // modifies LR, returns with LO still asserted p = obj.Appendp(ctxt, p) p.As = ABL p.Scond = C_SCOND_LS p.To.Type = obj.TYPE_BRANCH if ctxt.Cursym.Cfunc != 0 { p.To.Sym = obj.Linklookup(ctxt, "runtime.morestackc", 0) } else { p.To.Sym = ctxt.Symmorestack[bool2int(noctxt)] } // BLS start p = obj.Appendp(ctxt, p) p.As = ABLS p.To.Type = obj.TYPE_BRANCH p.Pcond = ctxt.Cursym.Text.Link return p }
func preprocess(ctxt *obj.Link, cursym *obj.LSym) { autosize := int32(0) if ctxt.Symmorestack[0] == nil { ctxt.Symmorestack[0] = obj.Linklookup(ctxt, "runtime.morestack", 0) ctxt.Symmorestack[1] = obj.Linklookup(ctxt, "runtime.morestack_noctxt", 0) } ctxt.Cursym = cursym if cursym.Text == nil || cursym.Text.Link == nil { return } softfloat(ctxt, cursym) p := cursym.Text autoffset := int32(p.To.Offset) if autoffset < 0 { autoffset = 0 } cursym.Locals = autoffset cursym.Args = p.To.U.Argsize if ctxt.Debugzerostack != 0 { if autoffset != 0 && p.From3.Offset&obj.NOSPLIT == 0 { // MOVW $4(R13), R1 p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_ADDR p.From.Reg = REG_R13 p.From.Offset = 4 p.To.Type = obj.TYPE_REG p.To.Reg = REG_R1 // MOVW $n(R13), R2 p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_ADDR p.From.Reg = REG_R13 p.From.Offset = 4 + int64(autoffset) p.To.Type = obj.TYPE_REG p.To.Reg = REG_R2 // MOVW $0, R3 p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_CONST p.From.Offset = 0 p.To.Type = obj.TYPE_REG p.To.Reg = REG_R3 // L: // MOVW.nil R3, 0(R1) +4 // CMP R1, R2 // BNE L pl := obj.Appendp(ctxt, p) p := pl p.As = AMOVW p.From.Type = obj.TYPE_REG p.From.Reg = REG_R3 p.To.Type = obj.TYPE_MEM p.To.Reg = REG_R1 p.To.Offset = 4 p.Scond |= C_PBIT p = obj.Appendp(ctxt, p) p.As = ACMP p.From.Type = obj.TYPE_REG p.From.Reg = REG_R1 p.Reg = REG_R2 p = obj.Appendp(ctxt, p) p.As = ABNE p.To.Type = obj.TYPE_BRANCH p.Pcond = pl } } /* * find leaf subroutines * strip NOPs * expand RET * expand BECOME pseudo */ var q1 *obj.Prog var q *obj.Prog for p := cursym.Text; p != nil; p = p.Link { switch p.As { case ACASE: if ctxt.Flag_shared != 0 { linkcase(p) } case obj.ATEXT: p.Mark |= LEAF case obj.ARET: break case ADIV, ADIVU, AMOD, AMODU: q = p if ctxt.Sym_div == nil { initdiv(ctxt) } cursym.Text.Mark &^= LEAF continue case obj.ANOP: q1 = p.Link q.Link = q1 /* q is non-nop */ if q1 != nil { q1.Mark |= p.Mark } continue case ABL, ABX, obj.ADUFFZERO, obj.ADUFFCOPY: cursym.Text.Mark &^= LEAF fallthrough case ABCASE, AB, ABEQ, ABNE, ABCS, ABHS, ABCC, ABLO, ABMI, ABPL, ABVS, ABVC, ABHI, ABLS, ABGE, ABLT, ABGT, ABLE: q1 = p.Pcond if q1 != nil { for q1.As == obj.ANOP { q1 = q1.Link p.Pcond = q1 } } } q = p } var o int var p1 *obj.Prog var p2 *obj.Prog var q2 *obj.Prog for p := cursym.Text; p != nil; p = p.Link { o = int(p.As) switch o { case obj.ATEXT: autosize = int32(p.To.Offset + 4) if autosize <= 4 { if cursym.Text.Mark&LEAF != 0 { p.To.Offset = -4 autosize = 0 } } if autosize == 0 && cursym.Text.Mark&LEAF == 0 { if ctxt.Debugvlog != 0 { fmt.Fprintf(ctxt.Bso, "save suppressed in: %s\n", cursym.Name) obj.Bflush(ctxt.Bso) } cursym.Text.Mark |= LEAF } if cursym.Text.Mark&LEAF != 0 { cursym.Leaf = 1 if autosize == 0 { break } } if p.From3.Offset&obj.NOSPLIT == 0 { p = stacksplit(ctxt, p, autosize, cursym.Text.From3.Offset&obj.NEEDCTXT == 0) // emit split check } // MOVW.W R14,$-autosize(SP) p = obj.Appendp(ctxt, p) p.As = AMOVW p.Scond |= C_WBIT p.From.Type = obj.TYPE_REG p.From.Reg = REGLINK p.To.Type = obj.TYPE_MEM p.To.Offset = int64(-autosize) p.To.Reg = REGSP p.Spadj = autosize if cursym.Text.From3.Offset&obj.WRAPPER != 0 { // if(g->panic != nil && g->panic->argp == FP) g->panic->argp = bottom-of-frame // // MOVW g_panic(g), R1 // CMP $0, R1 // B.EQ end // MOVW panic_argp(R1), R2 // ADD $(autosize+4), R13, R3 // CMP R2, R3 // B.NE end // ADD $4, R13, R4 // MOVW R4, panic_argp(R1) // end: // NOP // // The NOP is needed to give the jumps somewhere to land. // It is a liblink NOP, not an ARM NOP: it encodes to 0 instruction bytes. p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_MEM p.From.Reg = REGG p.From.Offset = 4 * int64(ctxt.Arch.Ptrsize) // G.panic p.To.Type = obj.TYPE_REG p.To.Reg = REG_R1 p = obj.Appendp(ctxt, p) p.As = ACMP p.From.Type = obj.TYPE_CONST p.From.Offset = 0 p.Reg = REG_R1 p = obj.Appendp(ctxt, p) p.As = ABEQ p.To.Type = obj.TYPE_BRANCH p1 = p p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_MEM p.From.Reg = REG_R1 p.From.Offset = 0 // Panic.argp p.To.Type = obj.TYPE_REG p.To.Reg = REG_R2 p = obj.Appendp(ctxt, p) p.As = AADD p.From.Type = obj.TYPE_CONST p.From.Offset = int64(autosize) + 4 p.Reg = REG_R13 p.To.Type = obj.TYPE_REG p.To.Reg = REG_R3 p = obj.Appendp(ctxt, p) p.As = ACMP p.From.Type = obj.TYPE_REG p.From.Reg = REG_R2 p.Reg = REG_R3 p = obj.Appendp(ctxt, p) p.As = ABNE p.To.Type = obj.TYPE_BRANCH p2 = p p = obj.Appendp(ctxt, p) p.As = AADD p.From.Type = obj.TYPE_CONST p.From.Offset = 4 p.Reg = REG_R13 p.To.Type = obj.TYPE_REG p.To.Reg = REG_R4 p = obj.Appendp(ctxt, p) p.As = AMOVW p.From.Type = obj.TYPE_REG p.From.Reg = REG_R4 p.To.Type = obj.TYPE_MEM p.To.Reg = REG_R1 p.To.Offset = 0 // Panic.argp p = obj.Appendp(ctxt, p) p.As = obj.ANOP p1.Pcond = p p2.Pcond = p } case obj.ARET: obj.Nocache(p) if cursym.Text.Mark&LEAF != 0 { if autosize == 0 { p.As = AB p.From = obj.Addr{} if p.To.Sym != nil { // retjmp p.To.Type = obj.TYPE_BRANCH } else { p.To.Type = obj.TYPE_MEM p.To.Offset = 0 p.To.Reg = REGLINK } break } } p.As = AMOVW p.Scond |= C_PBIT p.From.Type = obj.TYPE_MEM p.From.Offset = int64(autosize) p.From.Reg = REGSP p.To.Type = obj.TYPE_REG p.To.Reg = REGPC // If there are instructions following // this ARET, they come from a branch // with the same stackframe, so no spadj. if p.To.Sym != nil { // retjmp p.To.Reg = REGLINK q2 = obj.Appendp(ctxt, p) q2.As = AB q2.To.Type = obj.TYPE_BRANCH q2.To.Sym = p.To.Sym p.To.Sym = nil p = q2 } case AADD: if p.From.Type == obj.TYPE_CONST && p.From.Reg == 0 && p.To.Type == obj.TYPE_REG && p.To.Reg == REGSP { p.Spadj = int32(-p.From.Offset) } case ASUB: if p.From.Type == obj.TYPE_CONST && p.From.Reg == 0 && p.To.Type == obj.TYPE_REG && p.To.Reg == REGSP { p.Spadj = int32(p.From.Offset) } case ADIV, ADIVU, AMOD, AMODU: if ctxt.Debugdivmod != 0 { break } if p.From.Type != obj.TYPE_REG { break } if p.To.Type != obj.TYPE_REG { break } q1 = p /* MOV a,4(SP) */ p = obj.Appendp(ctxt, p) p.As = AMOVW p.Lineno = q1.Lineno p.From.Type = obj.TYPE_REG p.From.Reg = q1.From.Reg p.To.Type = obj.TYPE_MEM p.To.Reg = REGSP p.To.Offset = 4 /* MOV b,REGTMP */ p = obj.Appendp(ctxt, p) p.As = AMOVW p.Lineno = q1.Lineno p.From.Type = obj.TYPE_REG p.From.Reg = q1.Reg if q1.Reg == 0 { p.From.Reg = q1.To.Reg } p.To.Type = obj.TYPE_REG p.To.Reg = REGTMP p.To.Offset = 0 /* CALL appropriate */ p = obj.Appendp(ctxt, p) p.As = ABL p.Lineno = q1.Lineno p.To.Type = obj.TYPE_BRANCH switch o { case ADIV: p.To.Sym = ctxt.Sym_div case ADIVU: p.To.Sym = ctxt.Sym_divu case AMOD: p.To.Sym = ctxt.Sym_mod case AMODU: p.To.Sym = ctxt.Sym_modu } /* MOV REGTMP, b */ p = obj.Appendp(ctxt, p) p.As = AMOVW p.Lineno = q1.Lineno p.From.Type = obj.TYPE_REG p.From.Reg = REGTMP p.From.Offset = 0 p.To.Type = obj.TYPE_REG p.To.Reg = q1.To.Reg /* ADD $8,SP */ p = obj.Appendp(ctxt, p) p.As = AADD p.Lineno = q1.Lineno p.From.Type = obj.TYPE_CONST p.From.Reg = 0 p.From.Offset = 8 p.Reg = 0 p.To.Type = obj.TYPE_REG p.To.Reg = REGSP p.Spadj = -8 /* Keep saved LR at 0(SP) after SP change. */ /* MOVW 0(SP), REGTMP; MOVW REGTMP, -8!(SP) */ /* TODO: Remove SP adjustments; see issue 6699. */ q1.As = AMOVW q1.From.Type = obj.TYPE_MEM q1.From.Reg = REGSP q1.From.Offset = 0 q1.Reg = 0 q1.To.Type = obj.TYPE_REG q1.To.Reg = REGTMP /* SUB $8,SP */ q1 = obj.Appendp(ctxt, q1) q1.As = AMOVW q1.From.Type = obj.TYPE_REG q1.From.Reg = REGTMP q1.Reg = 0 q1.To.Type = obj.TYPE_MEM q1.To.Reg = REGSP q1.To.Offset = -8 q1.Scond |= C_WBIT q1.Spadj = 8 case AMOVW: if (p.Scond&C_WBIT != 0) && p.To.Type == obj.TYPE_MEM && p.To.Reg == REGSP { p.Spadj = int32(-p.To.Offset) } if (p.Scond&C_PBIT != 0) && p.From.Type == obj.TYPE_MEM && p.From.Reg == REGSP && p.To.Reg != REGPC { p.Spadj = int32(-p.From.Offset) } if p.From.Type == obj.TYPE_ADDR && p.From.Reg == REGSP && p.To.Type == obj.TYPE_REG && p.To.Reg == REGSP { p.Spadj = int32(-p.From.Offset) } } } }
/* * attempt to generate 64-bit * res = n * return 1 on success, 0 if op not handled. */ func cgen64(n *gc.Node, res *gc.Node) { if res.Op != gc.OINDREG && res.Op != gc.ONAME { gc.Dump("n", n) gc.Dump("res", res) gc.Fatal("cgen64 %v of %v", gc.Oconv(int(n.Op), 0), gc.Oconv(int(res.Op), 0)) } l := n.Left var t1 gc.Node if !l.Addable { gc.Tempname(&t1, l.Type) gc.Cgen(l, &t1) l = &t1 } var hi1 gc.Node var lo1 gc.Node split64(l, &lo1, &hi1) switch n.Op { default: gc.Fatal("cgen64 %v", gc.Oconv(int(n.Op), 0)) case gc.OMINUS: var lo2 gc.Node var hi2 gc.Node split64(res, &lo2, &hi2) gc.Regalloc(&t1, lo1.Type, nil) var al gc.Node gc.Regalloc(&al, lo1.Type, nil) var ah gc.Node gc.Regalloc(&ah, hi1.Type, nil) gins(arm.AMOVW, &lo1, &al) gins(arm.AMOVW, &hi1, &ah) gmove(ncon(0), &t1) p1 := gins(arm.ASUB, &al, &t1) p1.Scond |= arm.C_SBIT gins(arm.AMOVW, &t1, &lo2) gmove(ncon(0), &t1) gins(arm.ASBC, &ah, &t1) gins(arm.AMOVW, &t1, &hi2) gc.Regfree(&t1) gc.Regfree(&al) gc.Regfree(&ah) splitclean() splitclean() return case gc.OCOM: gc.Regalloc(&t1, lo1.Type, nil) gmove(ncon(^uint32(0)), &t1) var lo2 gc.Node var hi2 gc.Node split64(res, &lo2, &hi2) var n1 gc.Node gc.Regalloc(&n1, lo1.Type, nil) gins(arm.AMOVW, &lo1, &n1) gins(arm.AEOR, &t1, &n1) gins(arm.AMOVW, &n1, &lo2) gins(arm.AMOVW, &hi1, &n1) gins(arm.AEOR, &t1, &n1) gins(arm.AMOVW, &n1, &hi2) gc.Regfree(&t1) gc.Regfree(&n1) splitclean() splitclean() return // binary operators. // common setup below. case gc.OADD, gc.OSUB, gc.OMUL, gc.OLSH, gc.ORSH, gc.OAND, gc.OOR, gc.OXOR, gc.OLROT: break } // setup for binary operators r := n.Right if r != nil && !r.Addable { var t2 gc.Node gc.Tempname(&t2, r.Type) gc.Cgen(r, &t2) r = &t2 } var hi2 gc.Node var lo2 gc.Node if gc.Is64(r.Type) { split64(r, &lo2, &hi2) } var al gc.Node gc.Regalloc(&al, lo1.Type, nil) var ah gc.Node gc.Regalloc(&ah, hi1.Type, nil) // Do op. Leave result in ah:al. switch n.Op { default: gc.Fatal("cgen64: not implemented: %v\n", n) // TODO: Constants case gc.OADD: var bl gc.Node gc.Regalloc(&bl, gc.Types[gc.TPTR32], nil) var bh gc.Node gc.Regalloc(&bh, gc.Types[gc.TPTR32], nil) gins(arm.AMOVW, &hi1, &ah) gins(arm.AMOVW, &lo1, &al) gins(arm.AMOVW, &hi2, &bh) gins(arm.AMOVW, &lo2, &bl) p1 := gins(arm.AADD, &bl, &al) p1.Scond |= arm.C_SBIT gins(arm.AADC, &bh, &ah) gc.Regfree(&bl) gc.Regfree(&bh) // TODO: Constants. case gc.OSUB: var bl gc.Node gc.Regalloc(&bl, gc.Types[gc.TPTR32], nil) var bh gc.Node gc.Regalloc(&bh, gc.Types[gc.TPTR32], nil) gins(arm.AMOVW, &lo1, &al) gins(arm.AMOVW, &hi1, &ah) gins(arm.AMOVW, &lo2, &bl) gins(arm.AMOVW, &hi2, &bh) p1 := gins(arm.ASUB, &bl, &al) p1.Scond |= arm.C_SBIT gins(arm.ASBC, &bh, &ah) gc.Regfree(&bl) gc.Regfree(&bh) // TODO(kaib): this can be done with 4 regs and does not need 6 case gc.OMUL: var bl gc.Node gc.Regalloc(&bl, gc.Types[gc.TPTR32], nil) var bh gc.Node gc.Regalloc(&bh, gc.Types[gc.TPTR32], nil) var cl gc.Node gc.Regalloc(&cl, gc.Types[gc.TPTR32], nil) var ch gc.Node gc.Regalloc(&ch, gc.Types[gc.TPTR32], nil) // load args into bh:bl and bh:bl. gins(arm.AMOVW, &hi1, &bh) gins(arm.AMOVW, &lo1, &bl) gins(arm.AMOVW, &hi2, &ch) gins(arm.AMOVW, &lo2, &cl) // bl * cl -> ah al p1 := gins(arm.AMULLU, nil, nil) p1.From.Type = obj.TYPE_REG p1.From.Reg = bl.Reg p1.Reg = cl.Reg p1.To.Type = obj.TYPE_REGREG p1.To.Reg = ah.Reg p1.To.Offset = int64(al.Reg) //print("%v\n", p1); // bl * ch + ah -> ah p1 = gins(arm.AMULA, nil, nil) p1.From.Type = obj.TYPE_REG p1.From.Reg = bl.Reg p1.Reg = ch.Reg p1.To.Type = obj.TYPE_REGREG2 p1.To.Reg = ah.Reg p1.To.Offset = int64(ah.Reg) //print("%v\n", p1); // bh * cl + ah -> ah p1 = gins(arm.AMULA, nil, nil) p1.From.Type = obj.TYPE_REG p1.From.Reg = bh.Reg p1.Reg = cl.Reg p1.To.Type = obj.TYPE_REGREG2 p1.To.Reg = ah.Reg p1.To.Offset = int64(ah.Reg) //print("%v\n", p1); gc.Regfree(&bh) gc.Regfree(&bl) gc.Regfree(&ch) gc.Regfree(&cl) // We only rotate by a constant c in [0,64). // if c >= 32: // lo, hi = hi, lo // c -= 32 // if c == 0: // no-op // else: // t = hi // shld hi:lo, c // shld lo:t, c case gc.OLROT: v := uint64(r.Int()) var bl gc.Node gc.Regalloc(&bl, lo1.Type, nil) var bh gc.Node gc.Regalloc(&bh, hi1.Type, nil) if v >= 32 { // reverse during load to do the first 32 bits of rotate v -= 32 gins(arm.AMOVW, &hi1, &bl) gins(arm.AMOVW, &lo1, &bh) } else { gins(arm.AMOVW, &hi1, &bh) gins(arm.AMOVW, &lo1, &bl) } if v == 0 { gins(arm.AMOVW, &bh, &ah) gins(arm.AMOVW, &bl, &al) } else { // rotate by 1 <= v <= 31 // MOVW bl<<v, al // MOVW bh<<v, ah // OR bl>>(32-v), ah // OR bh>>(32-v), al gshift(arm.AMOVW, &bl, arm.SHIFT_LL, int32(v), &al) gshift(arm.AMOVW, &bh, arm.SHIFT_LL, int32(v), &ah) gshift(arm.AORR, &bl, arm.SHIFT_LR, int32(32-v), &ah) gshift(arm.AORR, &bh, arm.SHIFT_LR, int32(32-v), &al) } gc.Regfree(&bl) gc.Regfree(&bh) case gc.OLSH: var bl gc.Node gc.Regalloc(&bl, lo1.Type, nil) var bh gc.Node gc.Regalloc(&bh, hi1.Type, nil) gins(arm.AMOVW, &hi1, &bh) gins(arm.AMOVW, &lo1, &bl) var p6 *obj.Prog var s gc.Node var n1 gc.Node var creg gc.Node var p1 *obj.Prog var p2 *obj.Prog var p3 *obj.Prog var p4 *obj.Prog var p5 *obj.Prog if r.Op == gc.OLITERAL { v := uint64(r.Int()) if v >= 64 { // TODO(kaib): replace with gins(AMOVW, nodintconst(0), &al) // here and below (verify it optimizes to EOR) gins(arm.AEOR, &al, &al) gins(arm.AEOR, &ah, &ah) } else if v > 32 { gins(arm.AEOR, &al, &al) // MOVW bl<<(v-32), ah gshift(arm.AMOVW, &bl, arm.SHIFT_LL, int32(v-32), &ah) } else if v == 32 { gins(arm.AEOR, &al, &al) gins(arm.AMOVW, &bl, &ah) } else if v > 0 { // MOVW bl<<v, al gshift(arm.AMOVW, &bl, arm.SHIFT_LL, int32(v), &al) // MOVW bh<<v, ah gshift(arm.AMOVW, &bh, arm.SHIFT_LL, int32(v), &ah) // OR bl>>(32-v), ah gshift(arm.AORR, &bl, arm.SHIFT_LR, int32(32-v), &ah) } else { gins(arm.AMOVW, &bl, &al) gins(arm.AMOVW, &bh, &ah) } goto olsh_break } gc.Regalloc(&s, gc.Types[gc.TUINT32], nil) gc.Regalloc(&creg, gc.Types[gc.TUINT32], nil) if gc.Is64(r.Type) { // shift is >= 1<<32 var cl gc.Node var ch gc.Node split64(r, &cl, &ch) gmove(&ch, &s) gins(arm.ATST, &s, nil) p6 = gc.Gbranch(arm.ABNE, nil, 0) gmove(&cl, &s) splitclean() } else { gmove(r, &s) p6 = nil } gins(arm.ATST, &s, nil) // shift == 0 p1 = gins(arm.AMOVW, &bl, &al) p1.Scond = arm.C_SCOND_EQ p1 = gins(arm.AMOVW, &bh, &ah) p1.Scond = arm.C_SCOND_EQ p2 = gc.Gbranch(arm.ABEQ, nil, 0) // shift is < 32 gc.Nodconst(&n1, gc.Types[gc.TUINT32], 32) gmove(&n1, &creg) gins(arm.ACMP, &s, &creg) // MOVW.LO bl<<s, al p1 = gregshift(arm.AMOVW, &bl, arm.SHIFT_LL, &s, &al) p1.Scond = arm.C_SCOND_LO // MOVW.LO bh<<s, ah p1 = gregshift(arm.AMOVW, &bh, arm.SHIFT_LL, &s, &ah) p1.Scond = arm.C_SCOND_LO // SUB.LO s, creg p1 = gins(arm.ASUB, &s, &creg) p1.Scond = arm.C_SCOND_LO // OR.LO bl>>creg, ah p1 = gregshift(arm.AORR, &bl, arm.SHIFT_LR, &creg, &ah) p1.Scond = arm.C_SCOND_LO // BLO end p3 = gc.Gbranch(arm.ABLO, nil, 0) // shift == 32 p1 = gins(arm.AEOR, &al, &al) p1.Scond = arm.C_SCOND_EQ p1 = gins(arm.AMOVW, &bl, &ah) p1.Scond = arm.C_SCOND_EQ p4 = gc.Gbranch(arm.ABEQ, nil, 0) // shift is < 64 gc.Nodconst(&n1, gc.Types[gc.TUINT32], 64) gmove(&n1, &creg) gins(arm.ACMP, &s, &creg) // EOR.LO al, al p1 = gins(arm.AEOR, &al, &al) p1.Scond = arm.C_SCOND_LO // MOVW.LO creg>>1, creg p1 = gshift(arm.AMOVW, &creg, arm.SHIFT_LR, 1, &creg) p1.Scond = arm.C_SCOND_LO // SUB.LO creg, s p1 = gins(arm.ASUB, &creg, &s) p1.Scond = arm.C_SCOND_LO // MOVW bl<<s, ah p1 = gregshift(arm.AMOVW, &bl, arm.SHIFT_LL, &s, &ah) p1.Scond = arm.C_SCOND_LO p5 = gc.Gbranch(arm.ABLO, nil, 0) // shift >= 64 if p6 != nil { gc.Patch(p6, gc.Pc) } gins(arm.AEOR, &al, &al) gins(arm.AEOR, &ah, &ah) gc.Patch(p2, gc.Pc) gc.Patch(p3, gc.Pc) gc.Patch(p4, gc.Pc) gc.Patch(p5, gc.Pc) gc.Regfree(&s) gc.Regfree(&creg) olsh_break: gc.Regfree(&bl) gc.Regfree(&bh) case gc.ORSH: var bl gc.Node gc.Regalloc(&bl, lo1.Type, nil) var bh gc.Node gc.Regalloc(&bh, hi1.Type, nil) gins(arm.AMOVW, &hi1, &bh) gins(arm.AMOVW, &lo1, &bl) var p4 *obj.Prog var p5 *obj.Prog var n1 gc.Node var p6 *obj.Prog var s gc.Node var p1 *obj.Prog var p2 *obj.Prog var creg gc.Node var p3 *obj.Prog if r.Op == gc.OLITERAL { v := uint64(r.Int()) if v >= 64 { if bh.Type.Etype == gc.TINT32 { // MOVW bh->31, al gshift(arm.AMOVW, &bh, arm.SHIFT_AR, 31, &al) // MOVW bh->31, ah gshift(arm.AMOVW, &bh, arm.SHIFT_AR, 31, &ah) } else { gins(arm.AEOR, &al, &al) gins(arm.AEOR, &ah, &ah) } } else if v > 32 { if bh.Type.Etype == gc.TINT32 { // MOVW bh->(v-32), al gshift(arm.AMOVW, &bh, arm.SHIFT_AR, int32(v-32), &al) // MOVW bh->31, ah gshift(arm.AMOVW, &bh, arm.SHIFT_AR, 31, &ah) } else { // MOVW bh>>(v-32), al gshift(arm.AMOVW, &bh, arm.SHIFT_LR, int32(v-32), &al) gins(arm.AEOR, &ah, &ah) } } else if v == 32 { gins(arm.AMOVW, &bh, &al) if bh.Type.Etype == gc.TINT32 { // MOVW bh->31, ah gshift(arm.AMOVW, &bh, arm.SHIFT_AR, 31, &ah) } else { gins(arm.AEOR, &ah, &ah) } } else if v > 0 { // MOVW bl>>v, al gshift(arm.AMOVW, &bl, arm.SHIFT_LR, int32(v), &al) // OR bh<<(32-v), al gshift(arm.AORR, &bh, arm.SHIFT_LL, int32(32-v), &al) if bh.Type.Etype == gc.TINT32 { // MOVW bh->v, ah gshift(arm.AMOVW, &bh, arm.SHIFT_AR, int32(v), &ah) } else { // MOVW bh>>v, ah gshift(arm.AMOVW, &bh, arm.SHIFT_LR, int32(v), &ah) } } else { gins(arm.AMOVW, &bl, &al) gins(arm.AMOVW, &bh, &ah) } goto orsh_break } gc.Regalloc(&s, gc.Types[gc.TUINT32], nil) gc.Regalloc(&creg, gc.Types[gc.TUINT32], nil) if gc.Is64(r.Type) { // shift is >= 1<<32 var ch gc.Node var cl gc.Node split64(r, &cl, &ch) gmove(&ch, &s) gins(arm.ATST, &s, nil) var p1 *obj.Prog if bh.Type.Etype == gc.TINT32 { p1 = gshift(arm.AMOVW, &bh, arm.SHIFT_AR, 31, &ah) } else { p1 = gins(arm.AEOR, &ah, &ah) } p1.Scond = arm.C_SCOND_NE p6 = gc.Gbranch(arm.ABNE, nil, 0) gmove(&cl, &s) splitclean() } else { gmove(r, &s) p6 = nil } gins(arm.ATST, &s, nil) // shift == 0 p1 = gins(arm.AMOVW, &bl, &al) p1.Scond = arm.C_SCOND_EQ p1 = gins(arm.AMOVW, &bh, &ah) p1.Scond = arm.C_SCOND_EQ p2 = gc.Gbranch(arm.ABEQ, nil, 0) // check if shift is < 32 gc.Nodconst(&n1, gc.Types[gc.TUINT32], 32) gmove(&n1, &creg) gins(arm.ACMP, &s, &creg) // MOVW.LO bl>>s, al p1 = gregshift(arm.AMOVW, &bl, arm.SHIFT_LR, &s, &al) p1.Scond = arm.C_SCOND_LO // SUB.LO s,creg p1 = gins(arm.ASUB, &s, &creg) p1.Scond = arm.C_SCOND_LO // OR.LO bh<<(32-s), al p1 = gregshift(arm.AORR, &bh, arm.SHIFT_LL, &creg, &al) p1.Scond = arm.C_SCOND_LO if bh.Type.Etype == gc.TINT32 { // MOVW bh->s, ah p1 = gregshift(arm.AMOVW, &bh, arm.SHIFT_AR, &s, &ah) } else { // MOVW bh>>s, ah p1 = gregshift(arm.AMOVW, &bh, arm.SHIFT_LR, &s, &ah) } p1.Scond = arm.C_SCOND_LO // BLO end p3 = gc.Gbranch(arm.ABLO, nil, 0) // shift == 32 p1 = gins(arm.AMOVW, &bh, &al) p1.Scond = arm.C_SCOND_EQ if bh.Type.Etype == gc.TINT32 { gshift(arm.AMOVW, &bh, arm.SHIFT_AR, 31, &ah) } else { gins(arm.AEOR, &ah, &ah) } p4 = gc.Gbranch(arm.ABEQ, nil, 0) // check if shift is < 64 gc.Nodconst(&n1, gc.Types[gc.TUINT32], 64) gmove(&n1, &creg) gins(arm.ACMP, &s, &creg) // MOVW.LO creg>>1, creg p1 = gshift(arm.AMOVW, &creg, arm.SHIFT_LR, 1, &creg) p1.Scond = arm.C_SCOND_LO // SUB.LO creg, s p1 = gins(arm.ASUB, &creg, &s) p1.Scond = arm.C_SCOND_LO if bh.Type.Etype == gc.TINT32 { // MOVW bh->(s-32), al p1 := gregshift(arm.AMOVW, &bh, arm.SHIFT_AR, &s, &al) p1.Scond = arm.C_SCOND_LO } else { // MOVW bh>>(v-32), al p1 := gregshift(arm.AMOVW, &bh, arm.SHIFT_LR, &s, &al) p1.Scond = arm.C_SCOND_LO } // BLO end p5 = gc.Gbranch(arm.ABLO, nil, 0) // s >= 64 if p6 != nil { gc.Patch(p6, gc.Pc) } if bh.Type.Etype == gc.TINT32 { // MOVW bh->31, al gshift(arm.AMOVW, &bh, arm.SHIFT_AR, 31, &al) } else { gins(arm.AEOR, &al, &al) } gc.Patch(p2, gc.Pc) gc.Patch(p3, gc.Pc) gc.Patch(p4, gc.Pc) gc.Patch(p5, gc.Pc) gc.Regfree(&s) gc.Regfree(&creg) orsh_break: gc.Regfree(&bl) gc.Regfree(&bh) // TODO(kaib): literal optimizations // make constant the right side (it usually is anyway). // if(lo1.op == OLITERAL) { // nswap(&lo1, &lo2); // nswap(&hi1, &hi2); // } // if(lo2.op == OLITERAL) { // // special cases for constants. // lv = mpgetfix(lo2.val.u.xval); // hv = mpgetfix(hi2.val.u.xval); // splitclean(); // right side // split64(res, &lo2, &hi2); // switch(n->op) { // case OXOR: // gmove(&lo1, &lo2); // gmove(&hi1, &hi2); // switch(lv) { // case 0: // break; // case 0xffffffffu: // gins(ANOTL, N, &lo2); // break; // default: // gins(AXORL, ncon(lv), &lo2); // break; // } // switch(hv) { // case 0: // break; // case 0xffffffffu: // gins(ANOTL, N, &hi2); // break; // default: // gins(AXORL, ncon(hv), &hi2); // break; // } // break; // case OAND: // switch(lv) { // case 0: // gins(AMOVL, ncon(0), &lo2); // break; // default: // gmove(&lo1, &lo2); // if(lv != 0xffffffffu) // gins(AANDL, ncon(lv), &lo2); // break; // } // switch(hv) { // case 0: // gins(AMOVL, ncon(0), &hi2); // break; // default: // gmove(&hi1, &hi2); // if(hv != 0xffffffffu) // gins(AANDL, ncon(hv), &hi2); // break; // } // break; // case OOR: // switch(lv) { // case 0: // gmove(&lo1, &lo2); // break; // case 0xffffffffu: // gins(AMOVL, ncon(0xffffffffu), &lo2); // break; // default: // gmove(&lo1, &lo2); // gins(AORL, ncon(lv), &lo2); // break; // } // switch(hv) { // case 0: // gmove(&hi1, &hi2); // break; // case 0xffffffffu: // gins(AMOVL, ncon(0xffffffffu), &hi2); // break; // default: // gmove(&hi1, &hi2); // gins(AORL, ncon(hv), &hi2); // break; // } // break; // } // splitclean(); // splitclean(); // goto out; // } case gc.OXOR, gc.OAND, gc.OOR: var n1 gc.Node gc.Regalloc(&n1, lo1.Type, nil) gins(arm.AMOVW, &lo1, &al) gins(arm.AMOVW, &hi1, &ah) gins(arm.AMOVW, &lo2, &n1) gins(optoas(int(n.Op), lo1.Type), &n1, &al) gins(arm.AMOVW, &hi2, &n1) gins(optoas(int(n.Op), lo1.Type), &n1, &ah) gc.Regfree(&n1) } if gc.Is64(r.Type) { splitclean() } splitclean() split64(res, &lo1, &hi1) gins(arm.AMOVW, &al, &lo1) gins(arm.AMOVW, &ah, &hi1) splitclean() //out: gc.Regfree(&al) gc.Regfree(&ah) }
func preprocess(ctxt *obj.Link, cursym *obj.LSym) { if ctxt.Symmorestack[0] == nil { ctxt.Symmorestack[0] = obj.Linklookup(ctxt, "runtime.morestack", 0) ctxt.Symmorestack[1] = obj.Linklookup(ctxt, "runtime.morestack_noctxt", 0) } ctxt.Cursym = cursym if cursym.Text == nil || cursym.Text.Link == nil { return } p := cursym.Text textstksiz := p.To.Offset aoffset := int32(textstksiz) cursym.Args = p.To.U.Argsize cursym.Locals = int32(textstksiz) /* * find leaf subroutines * strip NOPs * expand RET */ obj.Bflush(ctxt.Bso) q := (*obj.Prog)(nil) var q1 *obj.Prog for p := cursym.Text; p != nil; p = p.Link { switch p.As { case obj.ATEXT: p.Mark |= LEAF case obj.ARET: break case obj.ANOP: q1 = p.Link q.Link = q1 /* q is non-nop */ q1.Mark |= p.Mark continue case ABL, obj.ADUFFZERO, obj.ADUFFCOPY: cursym.Text.Mark &^= LEAF fallthrough case ACBNZ, ACBZ, ACBNZW, ACBZW, ATBZ, ATBNZ, ABCASE, AB, ABEQ, ABNE, ABCS, ABHS, ABCC, ABLO, ABMI, ABPL, ABVS, ABVC, ABHI, ABLS, ABGE, ABLT, ABGT, ABLE, AADR, /* strange */ AADRP: q1 = p.Pcond if q1 != nil { for q1.As == obj.ANOP { q1 = q1.Link p.Pcond = q1 } } break } q = p } var o int var q2 *obj.Prog var retjmp *obj.LSym var stkadj int64 for p := cursym.Text; p != nil; p = p.Link { o = int(p.As) switch o { case obj.ATEXT: cursym.Text = p if textstksiz < 0 { ctxt.Autosize = 0 } else { ctxt.Autosize = int32(textstksiz + 8) } if (cursym.Text.Mark&LEAF != 0) && ctxt.Autosize <= 8 { ctxt.Autosize = 0 } else if ctxt.Autosize&(16-1) != 0 { stkadj = 16 - (int64(ctxt.Autosize) & (16 - 1)) ctxt.Autosize += int32(stkadj) cursym.Locals += int32(stkadj) } p.To.Offset = int64(ctxt.Autosize) - 8 if ctxt.Autosize == 0 && !(cursym.Text.Mark&LEAF != 0) { if ctxt.Debugvlog != 0 { fmt.Fprintf(ctxt.Bso, "save suppressed in: %s\n", cursym.Text.From.Sym.Name) } obj.Bflush(ctxt.Bso) cursym.Text.Mark |= LEAF } if !(p.From3.Offset&obj.NOSPLIT != 0) { p = stacksplit(ctxt, p, ctxt.Autosize, bool2int(cursym.Text.From3.Offset&obj.NEEDCTXT == 0)) // emit split check } aoffset = ctxt.Autosize if aoffset > 0xF0 { aoffset = 0xF0 } if cursym.Text.Mark&LEAF != 0 { cursym.Leaf = 1 if ctxt.Autosize == 0 { break } aoffset = 0 } q = p if ctxt.Autosize > aoffset { q = ctxt.NewProg() q.As = ASUB q.Lineno = p.Lineno q.From.Type = obj.TYPE_CONST q.From.Offset = int64(ctxt.Autosize) - int64(aoffset) q.To.Type = obj.TYPE_REG q.To.Reg = REGSP q.Spadj = int32(q.From.Offset) q.Link = p.Link p.Link = q if cursym.Text.Mark&LEAF != 0 { break } } q1 = ctxt.NewProg() q1.As = AMOVD q1.Lineno = p.Lineno q1.From.Type = obj.TYPE_REG q1.From.Reg = REGLINK q1.To.Type = obj.TYPE_MEM q1.Scond = C_XPRE q1.To.Offset = int64(-aoffset) q1.To.Reg = REGSP q1.Link = q.Link q1.Spadj = aoffset q.Link = q1 if cursym.Text.From3.Offset&obj.WRAPPER != 0 { // if(g->panic != nil && g->panic->argp == FP) g->panic->argp = bottom-of-frame // // MOV g_panic(g), R1 // CMP ZR, R1 // BEQ end // MOV panic_argp(R1), R2 // ADD $(autosize+8), RSP, R3 // CMP R2, R3 // BNE end // ADD $8, RSP, R4 // MOVD R4, panic_argp(R1) // end: // NOP // // The NOP is needed to give the jumps somewhere to land. // It is a liblink NOP, not a ARM64 NOP: it encodes to 0 instruction bytes. q = q1 q = obj.Appendp(ctxt, q) q.As = AMOVD q.From.Type = obj.TYPE_MEM q.From.Reg = REGG q.From.Offset = 4 * int64(ctxt.Arch.Ptrsize) // G.panic q.To.Type = obj.TYPE_REG q.To.Reg = REG_R1 q = obj.Appendp(ctxt, q) q.As = ACMP q.From.Type = obj.TYPE_REG q.From.Reg = REGZERO q.Reg = REG_R1 q = obj.Appendp(ctxt, q) q.As = ABEQ q.To.Type = obj.TYPE_BRANCH q1 = q q = obj.Appendp(ctxt, q) q.As = AMOVD q.From.Type = obj.TYPE_MEM q.From.Reg = REG_R1 q.From.Offset = 0 // Panic.argp q.To.Type = obj.TYPE_REG q.To.Reg = REG_R2 q = obj.Appendp(ctxt, q) q.As = AADD q.From.Type = obj.TYPE_CONST q.From.Offset = int64(ctxt.Autosize) + 8 q.Reg = REGSP q.To.Type = obj.TYPE_REG q.To.Reg = REG_R3 q = obj.Appendp(ctxt, q) q.As = ACMP q.From.Type = obj.TYPE_REG q.From.Reg = REG_R2 q.Reg = REG_R3 q = obj.Appendp(ctxt, q) q.As = ABNE q.To.Type = obj.TYPE_BRANCH q2 = q q = obj.Appendp(ctxt, q) q.As = AADD q.From.Type = obj.TYPE_CONST q.From.Offset = 8 q.Reg = REGSP q.To.Type = obj.TYPE_REG q.To.Reg = REG_R4 q = obj.Appendp(ctxt, q) q.As = AMOVD q.From.Type = obj.TYPE_REG q.From.Reg = REG_R4 q.To.Type = obj.TYPE_MEM q.To.Reg = REG_R1 q.To.Offset = 0 // Panic.argp q = obj.Appendp(ctxt, q) q.As = obj.ANOP q1.Pcond = q q2.Pcond = q } case obj.ARET: nocache(p) if p.From.Type == obj.TYPE_CONST { ctxt.Diag("using BECOME (%v) is not supported!", p) break } retjmp = p.To.Sym p.To = obj.Addr{} if cursym.Text.Mark&LEAF != 0 { if ctxt.Autosize != 0 { p.As = AADD p.From.Type = obj.TYPE_CONST p.From.Offset = int64(ctxt.Autosize) p.To.Type = obj.TYPE_REG p.To.Reg = REGSP p.Spadj = -ctxt.Autosize } } else { /* want write-back pre-indexed SP+autosize -> SP, loading REGLINK*/ aoffset = ctxt.Autosize if aoffset > 0xF0 { aoffset = 0xF0 } p.As = AMOVD p.From.Type = obj.TYPE_MEM p.Scond = C_XPOST p.From.Offset = int64(aoffset) p.From.Reg = REGSP p.To.Type = obj.TYPE_REG p.To.Reg = REGLINK p.Spadj = -aoffset if ctxt.Autosize > aoffset { q = ctxt.NewProg() q.As = AADD q.From.Type = obj.TYPE_CONST q.From.Offset = int64(ctxt.Autosize) - int64(aoffset) q.To.Type = obj.TYPE_REG q.To.Reg = REGSP q.Link = p.Link q.Spadj = int32(-q.From.Offset) q.Lineno = p.Lineno p.Link = q p = q } } if p.As != obj.ARET { q = ctxt.NewProg() q.Lineno = p.Lineno q.Link = p.Link p.Link = q p = q } if retjmp != nil { // retjmp p.As = AB p.To.Type = obj.TYPE_BRANCH p.To.Sym = retjmp p.Spadj = +ctxt.Autosize break } p.As = obj.ARET p.Lineno = p.Lineno p.To.Type = obj.TYPE_MEM p.To.Offset = 0 p.To.Reg = REGLINK p.Spadj = +ctxt.Autosize case AADD, ASUB: if p.To.Type == obj.TYPE_REG && p.To.Reg == REGSP && p.From.Type == obj.TYPE_CONST { if p.As == AADD { p.Spadj = int32(-p.From.Offset) } else { p.Spadj = int32(+p.From.Offset) } } break } } }
func blockcopy(n, res *gc.Node, osrc, odst, w int64) { // determine alignment. // want to avoid unaligned access, so have to use // smaller operations for less aligned types. // for example moving [4]byte must use 4 MOVB not 1 MOVW. align := int(n.Type.Align) var op int switch align { default: gc.Fatalf("sgen: invalid alignment %d for %v", align, n.Type) case 1: op = arm.AMOVB case 2: op = arm.AMOVH case 4: op = arm.AMOVW } if w%int64(align) != 0 { gc.Fatalf("sgen: unaligned size %d (align=%d) for %v", w, align, n.Type) } c := int32(w / int64(align)) if osrc%int64(align) != 0 || odst%int64(align) != 0 { gc.Fatalf("sgen: unaligned offset src %d or dst %d (align %d)", osrc, odst, align) } // if we are copying forward on the stack and // the src and dst overlap, then reverse direction dir := align if osrc < odst && int64(odst) < int64(osrc)+w { dir = -dir } if op == arm.AMOVW && !gc.Nacl && dir > 0 && c >= 4 && c <= 128 { var r0 gc.Node r0.Op = gc.OREGISTER r0.Reg = arm.REG_R0 var r1 gc.Node r1.Op = gc.OREGISTER r1.Reg = arm.REG_R0 + 1 var r2 gc.Node r2.Op = gc.OREGISTER r2.Reg = arm.REG_R0 + 2 var src gc.Node gc.Regalloc(&src, gc.Types[gc.Tptr], &r1) var dst gc.Node gc.Regalloc(&dst, gc.Types[gc.Tptr], &r2) if n.Ullman >= res.Ullman { // eval n first gc.Agen(n, &src) if res.Op == gc.ONAME { gc.Gvardef(res) } gc.Agen(res, &dst) } else { // eval res first if res.Op == gc.ONAME { gc.Gvardef(res) } gc.Agen(res, &dst) gc.Agen(n, &src) } var tmp gc.Node gc.Regalloc(&tmp, gc.Types[gc.Tptr], &r0) f := gc.Sysfunc("duffcopy") p := gins(obj.ADUFFCOPY, nil, f) gc.Afunclit(&p.To, f) // 8 and 128 = magic constants: see ../../runtime/asm_arm.s p.To.Offset = 8 * (128 - int64(c)) gc.Regfree(&tmp) gc.Regfree(&src) gc.Regfree(&dst) return } var dst gc.Node var src gc.Node if n.Ullman >= res.Ullman { gc.Agenr(n, &dst, res) // temporarily use dst gc.Regalloc(&src, gc.Types[gc.Tptr], nil) gins(arm.AMOVW, &dst, &src) if res.Op == gc.ONAME { gc.Gvardef(res) } gc.Agen(res, &dst) } else { if res.Op == gc.ONAME { gc.Gvardef(res) } gc.Agenr(res, &dst, res) gc.Agenr(n, &src, nil) } var tmp gc.Node gc.Regalloc(&tmp, gc.Types[gc.TUINT32], nil) // set up end marker var nend gc.Node if c >= 4 { gc.Regalloc(&nend, gc.Types[gc.TUINT32], nil) p := gins(arm.AMOVW, &src, &nend) p.From.Type = obj.TYPE_ADDR if dir < 0 { p.From.Offset = int64(dir) } else { p.From.Offset = w } } // move src and dest to the end of block if necessary if dir < 0 { p := gins(arm.AMOVW, &src, &src) p.From.Type = obj.TYPE_ADDR p.From.Offset = w + int64(dir) p = gins(arm.AMOVW, &dst, &dst) p.From.Type = obj.TYPE_ADDR p.From.Offset = w + int64(dir) } // move if c >= 4 { p := gins(op, &src, &tmp) p.From.Type = obj.TYPE_MEM p.From.Offset = int64(dir) p.Scond |= arm.C_PBIT ploop := p p = gins(op, &tmp, &dst) p.To.Type = obj.TYPE_MEM p.To.Offset = int64(dir) p.Scond |= arm.C_PBIT p = gins(arm.ACMP, &src, nil) raddr(&nend, p) gc.Patch(gc.Gbranch(arm.ABNE, nil, 0), ploop) gc.Regfree(&nend) } else { var p *obj.Prog for { tmp14 := c c-- if tmp14 <= 0 { break } p = gins(op, &src, &tmp) p.From.Type = obj.TYPE_MEM p.From.Offset = int64(dir) p.Scond |= arm.C_PBIT p = gins(op, &tmp, &dst) p.To.Type = obj.TYPE_MEM p.To.Offset = int64(dir) p.Scond |= arm.C_PBIT } } gc.Regfree(&dst) gc.Regfree(&src) gc.Regfree(&tmp) }
func preprocess(ctxt *obj.Link, cursym *obj.LSym) { ctxt.Cursym = cursym if cursym.Text == nil || cursym.Text.Link == nil { return } p := cursym.Text textstksiz := p.To.Offset aoffset := int32(textstksiz) cursym.Args = p.To.Val.(int32) cursym.Locals = int32(textstksiz) /* * find leaf subroutines * strip NOPs * expand RET */ q := (*obj.Prog)(nil) var q1 *obj.Prog for p := cursym.Text; p != nil; p = p.Link { switch p.As { case obj.ATEXT: p.Mark |= LEAF case obj.ARET: break case obj.ANOP: q1 = p.Link q.Link = q1 /* q is non-nop */ q1.Mark |= p.Mark continue case ABL, obj.ADUFFZERO, obj.ADUFFCOPY: cursym.Text.Mark &^= LEAF fallthrough case ACBNZ, ACBZ, ACBNZW, ACBZW, ATBZ, ATBNZ, AB, ABEQ, ABNE, ABCS, ABHS, ABCC, ABLO, ABMI, ABPL, ABVS, ABVC, ABHI, ABLS, ABGE, ABLT, ABGT, ABLE, AADR, /* strange */ AADRP: q1 = p.Pcond if q1 != nil { for q1.As == obj.ANOP { q1 = q1.Link p.Pcond = q1 } } break } q = p } var q2 *obj.Prog var retjmp *obj.LSym for p := cursym.Text; p != nil; p = p.Link { o := p.As switch o { case obj.ATEXT: cursym.Text = p if textstksiz < 0 { ctxt.Autosize = 0 } else { ctxt.Autosize = int32(textstksiz + 8) } if (cursym.Text.Mark&LEAF != 0) && ctxt.Autosize <= 8 { ctxt.Autosize = 0 } else if ctxt.Autosize&(16-1) != 0 { // The frame includes an LR. // If the frame size is 8, it's only an LR, // so there's no potential for breaking references to // local variables by growing the frame size, // because there are no local variables. // But otherwise, if there is a non-empty locals section, // the author of the code is responsible for making sure // that the frame size is 8 mod 16. if ctxt.Autosize == 8 { ctxt.Autosize += 8 cursym.Locals += 8 } else { ctxt.Diag("%v: unaligned frame size %d - must be 8 mod 16 (or 0)", p, ctxt.Autosize-8) } } p.To.Offset = int64(ctxt.Autosize) - 8 if ctxt.Autosize == 0 && !(cursym.Text.Mark&LEAF != 0) { if ctxt.Debugvlog != 0 { ctxt.Logf("save suppressed in: %s\n", cursym.Text.From.Sym.Name) } cursym.Text.Mark |= LEAF } if !(p.From3.Offset&obj.NOSPLIT != 0) { p = stacksplit(ctxt, p, ctxt.Autosize) // emit split check } aoffset = ctxt.Autosize if aoffset > 0xF0 { aoffset = 0xF0 } if cursym.Text.Mark&LEAF != 0 { cursym.Leaf = true if ctxt.Autosize == 0 { break } aoffset = 0 } q = p if ctxt.Autosize > aoffset { q = ctxt.NewProg() q.As = ASUB q.Lineno = p.Lineno q.From.Type = obj.TYPE_CONST q.From.Offset = int64(ctxt.Autosize) - int64(aoffset) q.To.Type = obj.TYPE_REG q.To.Reg = REGSP q.Spadj = int32(q.From.Offset) q.Link = p.Link p.Link = q if cursym.Text.Mark&LEAF != 0 { break } } q1 = ctxt.NewProg() q1.As = AMOVD q1.Lineno = p.Lineno q1.From.Type = obj.TYPE_REG q1.From.Reg = REGLINK q1.To.Type = obj.TYPE_MEM q1.Scond = C_XPRE q1.To.Offset = int64(-aoffset) q1.To.Reg = REGSP q1.Link = q.Link q1.Spadj = aoffset q.Link = q1 if cursym.Text.From3.Offset&obj.WRAPPER != 0 { // if(g->panic != nil && g->panic->argp == FP) g->panic->argp = bottom-of-frame // // MOV g_panic(g), R1 // CMP ZR, R1 // BEQ end // MOV panic_argp(R1), R2 // ADD $(autosize+8), RSP, R3 // CMP R2, R3 // BNE end // ADD $8, RSP, R4 // MOVD R4, panic_argp(R1) // end: // NOP // // The NOP is needed to give the jumps somewhere to land. // It is a liblink NOP, not a ARM64 NOP: it encodes to 0 instruction bytes. q = q1 q = obj.Appendp(ctxt, q) q.As = AMOVD q.From.Type = obj.TYPE_MEM q.From.Reg = REGG q.From.Offset = 4 * int64(ctxt.Arch.PtrSize) // G.panic q.To.Type = obj.TYPE_REG q.To.Reg = REG_R1 q = obj.Appendp(ctxt, q) q.As = ACMP q.From.Type = obj.TYPE_REG q.From.Reg = REGZERO q.Reg = REG_R1 q = obj.Appendp(ctxt, q) q.As = ABEQ q.To.Type = obj.TYPE_BRANCH q1 = q q = obj.Appendp(ctxt, q) q.As = AMOVD q.From.Type = obj.TYPE_MEM q.From.Reg = REG_R1 q.From.Offset = 0 // Panic.argp q.To.Type = obj.TYPE_REG q.To.Reg = REG_R2 q = obj.Appendp(ctxt, q) q.As = AADD q.From.Type = obj.TYPE_CONST q.From.Offset = int64(ctxt.Autosize) + 8 q.Reg = REGSP q.To.Type = obj.TYPE_REG q.To.Reg = REG_R3 q = obj.Appendp(ctxt, q) q.As = ACMP q.From.Type = obj.TYPE_REG q.From.Reg = REG_R2 q.Reg = REG_R3 q = obj.Appendp(ctxt, q) q.As = ABNE q.To.Type = obj.TYPE_BRANCH q2 = q q = obj.Appendp(ctxt, q) q.As = AADD q.From.Type = obj.TYPE_CONST q.From.Offset = 8 q.Reg = REGSP q.To.Type = obj.TYPE_REG q.To.Reg = REG_R4 q = obj.Appendp(ctxt, q) q.As = AMOVD q.From.Type = obj.TYPE_REG q.From.Reg = REG_R4 q.To.Type = obj.TYPE_MEM q.To.Reg = REG_R1 q.To.Offset = 0 // Panic.argp q = obj.Appendp(ctxt, q) q.As = obj.ANOP q1.Pcond = q q2.Pcond = q } case obj.ARET: nocache(p) if p.From.Type == obj.TYPE_CONST { ctxt.Diag("using BECOME (%v) is not supported!", p) break } retjmp = p.To.Sym p.To = obj.Addr{} if cursym.Text.Mark&LEAF != 0 { if ctxt.Autosize != 0 { p.As = AADD p.From.Type = obj.TYPE_CONST p.From.Offset = int64(ctxt.Autosize) p.To.Type = obj.TYPE_REG p.To.Reg = REGSP p.Spadj = -ctxt.Autosize } } else { /* want write-back pre-indexed SP+autosize -> SP, loading REGLINK*/ aoffset = ctxt.Autosize if aoffset > 0xF0 { aoffset = 0xF0 } p.As = AMOVD p.From.Type = obj.TYPE_MEM p.Scond = C_XPOST p.From.Offset = int64(aoffset) p.From.Reg = REGSP p.To.Type = obj.TYPE_REG p.To.Reg = REGLINK p.Spadj = -aoffset if ctxt.Autosize > aoffset { q = ctxt.NewProg() q.As = AADD q.From.Type = obj.TYPE_CONST q.From.Offset = int64(ctxt.Autosize) - int64(aoffset) q.To.Type = obj.TYPE_REG q.To.Reg = REGSP q.Link = p.Link q.Spadj = int32(-q.From.Offset) q.Lineno = p.Lineno p.Link = q p = q } } if p.As != obj.ARET { q = ctxt.NewProg() q.Lineno = p.Lineno q.Link = p.Link p.Link = q p = q } if retjmp != nil { // retjmp p.As = AB p.To.Type = obj.TYPE_BRANCH p.To.Sym = retjmp p.Spadj = +ctxt.Autosize break } p.As = obj.ARET p.To.Type = obj.TYPE_MEM p.To.Offset = 0 p.To.Reg = REGLINK p.Spadj = +ctxt.Autosize case AADD, ASUB: if p.To.Type == obj.TYPE_REG && p.To.Reg == REGSP && p.From.Type == obj.TYPE_CONST { if p.As == AADD { p.Spadj = int32(-p.From.Offset) } else { p.Spadj = int32(+p.From.Offset) } } break } } }