示例#1
0
文件: ggen.go 项目: ckeyer/gosrc
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 = appendpp(p, ppc64.AMOVD, obj.TYPE_REG, ppc64.REGZERO, 0, obj.TYPE_MEM, ppc64.REGSP, gc.Ctxt.FixedFrameSize()+frame+lo+i)
		}
	} else if cnt <= int64(128*gc.Widthptr) {
		p = appendpp(p, ppc64.AADD, obj.TYPE_CONST, 0, gc.Ctxt.FixedFrameSize()+frame+lo-8, obj.TYPE_REG, ppc64.REGRT1, 0)
		p.Reg = ppc64.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, ppc64.AMOVD, obj.TYPE_CONST, 0, gc.Ctxt.FixedFrameSize()+frame+lo-8, obj.TYPE_REG, ppc64.REGTMP, 0)
		p = appendpp(p, ppc64.AADD, obj.TYPE_REG, ppc64.REGTMP, 0, obj.TYPE_REG, ppc64.REGRT1, 0)
		p.Reg = ppc64.REGSP
		p = appendpp(p, ppc64.AMOVD, obj.TYPE_CONST, 0, cnt, obj.TYPE_REG, ppc64.REGTMP, 0)
		p = appendpp(p, ppc64.AADD, obj.TYPE_REG, ppc64.REGTMP, 0, obj.TYPE_REG, ppc64.REGRT2, 0)
		p.Reg = ppc64.REGRT1
		p = appendpp(p, ppc64.AMOVDU, obj.TYPE_REG, ppc64.REGZERO, 0, obj.TYPE_MEM, ppc64.REGRT1, int64(gc.Widthptr))
		p1 := p
		p = appendpp(p, ppc64.ACMP, obj.TYPE_REG, ppc64.REGRT1, 0, obj.TYPE_REG, ppc64.REGRT2, 0)
		p = appendpp(p, ppc64.ABNE, obj.TYPE_NONE, 0, 0, obj.TYPE_BRANCH, 0, 0)
		gc.Patch(p, p1)
	}

	return p
}
示例#2
0
文件: gsubr.go 项目: ckeyer/gosrc
/*
 * insert n into reg slot of p
 */
func raddr(n *gc.Node, p *obj.Prog) {
	var a obj.Addr
	gc.Naddr(&a, n)
	if a.Type != obj.TYPE_REG {
		if n != nil {
			gc.Fatalf("bad in raddr: %v", gc.Oconv(int(n.Op), 0))
		} else {
			gc.Fatalf("bad in raddr: <null>")
		}
		p.Reg = 0
	} else {
		p.Reg = a.Reg
	}
}
示例#3
0
文件: peep.go 项目: ckeyer/gosrc
// copysub1 replaces v with s in p1->reg if f!=0 or indicates if it could if f==0.
// Returns 1 on failure to substitute (it always succeeds on mips).
func copysub1(p1 *obj.Prog, v *obj.Addr, s *obj.Addr, f int) int {
	if f != 0 {
		if copyau1(p1, v) {
			p1.Reg = s.Reg
		}
	}
	return 0
}
示例#4
0
文件: ggen.go 项目: ckeyer/gosrc
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 = appendpp(p, mips.AMOVV, obj.TYPE_REG, mips.REGZERO, 0, obj.TYPE_MEM, mips.REGSP, 8+frame+lo+i)
		}
		// TODO(dfc): https://golang.org/issue/12108
		// If DUFFZERO is used inside a tail call (see genwrapper) it will
		// overwrite the link register.
	} else if false && cnt <= int64(128*gc.Widthptr) {
		p = appendpp(p, mips.AADDV, obj.TYPE_CONST, 0, 8+frame+lo-8, obj.TYPE_REG, mips.REGRT1, 0)
		p.Reg = mips.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 = 8 * (128 - cnt/int64(gc.Widthptr))
	} else {
		//	ADDV	$(8+frame+lo-8), SP, r1
		//	ADDV	$cnt, r1, r2
		// loop:
		//	MOVV	R0, (Widthptr)r1
		//	ADDV	$Widthptr, r1
		//	BNE		r1, r2, loop
		p = appendpp(p, mips.AADDV, obj.TYPE_CONST, 0, 8+frame+lo-8, obj.TYPE_REG, mips.REGRT1, 0)
		p.Reg = mips.REGSP
		p = appendpp(p, mips.AADDV, obj.TYPE_CONST, 0, cnt, obj.TYPE_REG, mips.REGRT2, 0)
		p.Reg = mips.REGRT1
		p = appendpp(p, mips.AMOVV, obj.TYPE_REG, mips.REGZERO, 0, obj.TYPE_MEM, mips.REGRT1, int64(gc.Widthptr))
		p1 := p
		p = appendpp(p, mips.AADDV, obj.TYPE_CONST, 0, int64(gc.Widthptr), obj.TYPE_REG, mips.REGRT1, 0)
		p = appendpp(p, mips.ABNE, obj.TYPE_REG, mips.REGRT1, 0, obj.TYPE_BRANCH, 0, 0)
		p.Reg = mips.REGRT2
		gc.Patch(p, p1)
	}

	return p
}
示例#5
0
文件: ggen.go 项目: ckeyer/gosrc
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
}
示例#6
0
文件: ggen.go 项目: ckeyer/gosrc
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 = 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 = appendpp(p, arm64.AMOVD, obj.TYPE_REG, arm64.REGSP, 0, obj.TYPE_REG, arm64.REGRT1, 0)
		p = appendpp(p, arm64.AADD, obj.TYPE_CONST, 0, 8+frame+lo-8, obj.TYPE_REG, arm64.REGRT1, 0)
		p.Reg = arm64.REGRT1
		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, arm64.AMOVD, obj.TYPE_CONST, 0, 8+frame+lo-8, obj.TYPE_REG, arm64.REGTMP, 0)
		p = appendpp(p, arm64.AMOVD, obj.TYPE_REG, arm64.REGSP, 0, obj.TYPE_REG, arm64.REGRT1, 0)
		p = appendpp(p, arm64.AADD, obj.TYPE_REG, arm64.REGTMP, 0, obj.TYPE_REG, arm64.REGRT1, 0)
		p.Reg = arm64.REGRT1
		p = appendpp(p, arm64.AMOVD, obj.TYPE_CONST, 0, cnt, obj.TYPE_REG, arm64.REGTMP, 0)
		p = appendpp(p, arm64.AADD, obj.TYPE_REG, arm64.REGTMP, 0, obj.TYPE_REG, arm64.REGRT2, 0)
		p.Reg = arm64.REGRT1
		p = 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 = appendpp(p, arm64.ACMP, obj.TYPE_REG, arm64.REGRT1, 0, obj.TYPE_NONE, 0, 0)
		p.Reg = arm64.REGRT2
		p = appendpp(p, arm64.ABNE, obj.TYPE_NONE, 0, 0, obj.TYPE_BRANCH, 0, 0)
		gc.Patch(p, p1)
	}

	return p
}
示例#7
0
文件: ggen.go 项目: ckeyer/gosrc
/*
 * generate high multiply
 *  res = (nl * nr) >> wordsize
 */
func cgen_hmul(nl *gc.Node, nr *gc.Node, res *gc.Node) {
	if nl.Ullman < nr.Ullman {
		nl, nr = nr, nl
	}

	t := nl.Type
	w := int(t.Width * 8)
	var n1 gc.Node
	gc.Regalloc(&n1, t, res)
	gc.Cgen(nl, &n1)
	var n2 gc.Node
	gc.Regalloc(&n2, t, nil)
	gc.Cgen(nr, &n2)
	switch gc.Simtype[t.Etype] {
	case gc.TINT8,
		gc.TINT16:
		gins(optoas(gc.OMUL, t), &n2, &n1)
		gshift(arm.AMOVW, &n1, arm.SHIFT_AR, int32(w), &n1)

	case gc.TUINT8,
		gc.TUINT16:
		gins(optoas(gc.OMUL, t), &n2, &n1)
		gshift(arm.AMOVW, &n1, arm.SHIFT_LR, int32(w), &n1)

		// perform a long multiplication.
	case gc.TINT32,
		gc.TUINT32:
		var p *obj.Prog
		if gc.Issigned[t.Etype] {
			p = gins(arm.AMULL, &n2, nil)
		} else {
			p = gins(arm.AMULLU, &n2, nil)
		}

		// n2 * n1 -> (n1 n2)
		p.Reg = n1.Reg

		p.To.Type = obj.TYPE_REGREG
		p.To.Reg = n1.Reg
		p.To.Offset = int64(n2.Reg)

	default:
		gc.Fatalf("cgen_hmul %v", t)
	}

	gc.Cgen(&n1, res)
	gc.Regfree(&n1)
	gc.Regfree(&n2)
}
示例#8
0
文件: peep.go 项目: ckeyer/gosrc
// If s==nil, copyu returns the set/use of v in p; otherwise, it
// modifies p to replace reads of v with reads of s and returns 0 for
// success or non-zero for failure.
//
// If s==nil, copy returns one of the following values:
// 	1 if v only used
//	2 if v is set and used in one address (read-alter-rewrite;
// 	  can't substitute)
//	3 if v is only set
//	4 if v is set in one address and used in another (so addresses
// 	  can be rewritten independently)
//	0 otherwise (not touched)
func copyu(p *obj.Prog, v *obj.Addr, s *obj.Addr) int {
	if p.From3Type() != obj.TYPE_NONE {
		// never generates a from3
		fmt.Printf("copyu: from3 (%v) not implemented\n", gc.Ctxt.Dconv(p.From3))
	}

	switch p.As {
	default:
		fmt.Printf("copyu: can't find %v\n", obj.Aconv(int(p.As)))
		return 2

	case obj.ANOP, /* read p->from, write p->to */
		mips.AMOVV,
		mips.AMOVF,
		mips.AMOVD,
		mips.AMOVH,
		mips.AMOVHU,
		mips.AMOVB,
		mips.AMOVBU,
		mips.AMOVW,
		mips.AMOVWU,
		mips.AMOVFD,
		mips.AMOVDF,
		mips.AMOVDW,
		mips.AMOVWD,
		mips.AMOVFW,
		mips.AMOVWF,
		mips.AMOVDV,
		mips.AMOVVD,
		mips.AMOVFV,
		mips.AMOVVF,
		mips.ATRUNCFV,
		mips.ATRUNCDV,
		mips.ATRUNCFW,
		mips.ATRUNCDW:
		if s != nil {
			if copysub(&p.From, v, s, 1) != 0 {
				return 1
			}

			// Update only indirect uses of v in p->to
			if !copyas(&p.To, v) {
				if copysub(&p.To, v, s, 1) != 0 {
					return 1
				}
			}
			return 0
		}

		if copyas(&p.To, v) {
			// Fix up implicit from
			if p.From.Type == obj.TYPE_NONE {
				p.From = p.To
			}
			if copyau(&p.From, v) {
				return 4
			}
			return 3
		}

		if copyau(&p.From, v) {
			return 1
		}
		if copyau(&p.To, v) {
			// p->to only indirectly uses v
			return 1
		}

		return 0

	case mips.ASGT, /* read p->from, read p->reg, write p->to */
		mips.ASGTU,

		mips.AADD,
		mips.AADDU,
		mips.ASUB,
		mips.ASUBU,
		mips.ASLL,
		mips.ASRL,
		mips.ASRA,
		mips.AOR,
		mips.ANOR,
		mips.AAND,
		mips.AXOR,

		mips.AADDV,
		mips.AADDVU,
		mips.ASUBV,
		mips.ASUBVU,
		mips.ASLLV,
		mips.ASRLV,
		mips.ASRAV,

		mips.AADDF,
		mips.AADDD,
		mips.ASUBF,
		mips.ASUBD,
		mips.AMULF,
		mips.AMULD,
		mips.ADIVF,
		mips.ADIVD:
		if s != nil {
			if copysub(&p.From, v, s, 1) != 0 {
				return 1
			}
			if copysub1(p, v, s, 1) != 0 {
				return 1
			}

			// Update only indirect uses of v in p->to
			if !copyas(&p.To, v) {
				if copysub(&p.To, v, s, 1) != 0 {
					return 1
				}
			}
			return 0
		}

		if copyas(&p.To, v) {
			if p.Reg == 0 {
				// Fix up implicit reg (e.g., ADD
				// R3,R4 -> ADD R3,R4,R4) so we can
				// update reg and to separately.
				p.Reg = p.To.Reg
			}

			if copyau(&p.From, v) {
				return 4
			}
			if copyau1(p, v) {
				return 4
			}
			return 3
		}

		if copyau(&p.From, v) {
			return 1
		}
		if copyau1(p, v) {
			return 1
		}
		if copyau(&p.To, v) {
			return 1
		}
		return 0

	case obj.ACHECKNIL, /* read p->from */
		mips.ABEQ, /* read p->from, read p->reg */
		mips.ABNE,
		mips.ABGTZ,
		mips.ABGEZ,
		mips.ABLTZ,
		mips.ABLEZ,

		mips.ACMPEQD,
		mips.ACMPEQF,
		mips.ACMPGED,
		mips.ACMPGEF,
		mips.ACMPGTD,
		mips.ACMPGTF,
		mips.ABFPF,
		mips.ABFPT,

		mips.AMUL,
		mips.AMULU,
		mips.ADIV,
		mips.ADIVU,
		mips.AMULV,
		mips.AMULVU,
		mips.ADIVV,
		mips.ADIVVU:
		if s != nil {
			if copysub(&p.From, v, s, 1) != 0 {
				return 1
			}
			return copysub1(p, v, s, 1)
		}

		if copyau(&p.From, v) {
			return 1
		}
		if copyau1(p, v) {
			return 1
		}
		return 0

	case mips.AJMP: /* read p->to */
		if s != nil {
			if copysub(&p.To, v, s, 1) != 0 {
				return 1
			}
			return 0
		}

		if copyau(&p.To, v) {
			return 1
		}
		return 0

	case mips.ARET: /* funny */
		if s != nil {
			return 0
		}

		// All registers die at this point, so claim
		// everything is set (and not used).
		return 3

	case mips.AJAL: /* funny */
		if v.Type == obj.TYPE_REG {
			// TODO(rsc): REG_R0 and REG_F0 used to be
			// (when register numbers started at 0) exregoffset and exfregoffset,
			// which are unset entirely.
			// It's strange that this handles R0 and F0 differently from the other
			// registers. Possible failure to optimize?
			if mips.REG_R0 < v.Reg && v.Reg <= mips.REG_R31 {
				return 2
			}
			if v.Reg == mips.REGARG {
				return 2
			}
			if mips.REG_F0 < v.Reg && v.Reg <= mips.REG_F31 {
				return 2
			}
		}

		if p.From.Type == obj.TYPE_REG && v.Type == obj.TYPE_REG && p.From.Reg == v.Reg {
			return 2
		}

		if s != nil {
			if copysub(&p.To, v, s, 1) != 0 {
				return 1
			}
			return 0
		}

		if copyau(&p.To, v) {
			return 4
		}
		return 3

	// R0 is zero, used by DUFFZERO, cannot be substituted.
	// R1 is ptr to memory, used and set, cannot be substituted.
	case obj.ADUFFZERO:
		if v.Type == obj.TYPE_REG {
			if v.Reg == 0 {
				return 1
			}
			if v.Reg == 1 {
				return 2
			}
		}

		return 0

	// R1, R2 are ptr to src, dst, used and set, cannot be substituted.
	// R3 is scratch, set by DUFFCOPY, cannot be substituted.
	case obj.ADUFFCOPY:
		if v.Type == obj.TYPE_REG {
			if v.Reg == 1 || v.Reg == 2 {
				return 2
			}
			if v.Reg == 3 {
				return 3
			}
		}

		return 0

	case obj.ATEXT: /* funny */
		if v.Type == obj.TYPE_REG {
			if v.Reg == mips.REGARG {
				return 3
			}
		}
		return 0

	case obj.APCDATA,
		obj.AFUNCDATA,
		obj.AVARDEF,
		obj.AVARKILL,
		obj.AVARLIVE,
		obj.AUSEFIELD:
		return 0
	}
}
示例#9
0
文件: peep.go 项目: ckeyer/gosrc
// UNUSED
func peep(firstp *obj.Prog) {
	g := (*gc.Graph)(gc.Flowstart(firstp, nil))
	if g == nil {
		return
	}
	gactive = 0

	var r *gc.Flow
	var p *obj.Prog
	var t int
loop1:
	if gc.Debug['P'] != 0 && gc.Debug['v'] != 0 {
		gc.Dumpit("loop1", g.Start, 0)
	}

	t = 0
	for r = g.Start; r != nil; r = r.Link {
		p = r.Prog
		switch p.As {
		/*
		 * elide shift into TYPE_SHIFT operand of subsequent instruction
		 */
		//			if(shiftprop(r)) {
		//				excise(r);
		//				t++;
		//				break;
		//			}
		case arm.ASLL,
			arm.ASRL,
			arm.ASRA:
			break

		case arm.AMOVB,
			arm.AMOVH,
			arm.AMOVW,
			arm.AMOVF,
			arm.AMOVD:
			if regtyp(&p.From) {
				if p.From.Type == p.To.Type && isfloatreg(&p.From) == isfloatreg(&p.To) {
					if p.Scond == arm.C_SCOND_NONE {
						if copyprop(g, r) {
							excise(r)
							t++
							break
						}

						if subprop(r) && copyprop(g, r) {
							excise(r)
							t++
							break
						}
					}
				}
			}

		case arm.AMOVHS,
			arm.AMOVHU,
			arm.AMOVBS,
			arm.AMOVBU:
			if p.From.Type == obj.TYPE_REG {
				if shortprop(r) {
					t++
				}
			}
		}
	}

	/*
		if(p->scond == C_SCOND_NONE)
		if(regtyp(&p->to))
		if(isdconst(&p->from)) {
			constprop(&p->from, &p->to, r->s1);
		}
		break;
	*/
	if t != 0 {
		goto loop1
	}

	for r := (*gc.Flow)(g.Start); r != nil; r = r.Link {
		p = r.Prog
		switch p.As {
		/*
		 * EOR -1,x,y => MVN x,y
		 */
		case arm.AEOR:
			if isdconst(&p.From) && p.From.Offset == -1 {
				p.As = arm.AMVN
				p.From.Type = obj.TYPE_REG
				if p.Reg != 0 {
					p.From.Reg = p.Reg
				} else {
					p.From.Reg = p.To.Reg
				}
				p.Reg = 0
			}
		}
	}

	for r := (*gc.Flow)(g.Start); r != nil; r = r.Link {
		p = r.Prog
		switch p.As {
		case arm.AMOVW,
			arm.AMOVB,
			arm.AMOVBS,
			arm.AMOVBU:
			if p.From.Type == obj.TYPE_MEM && p.From.Offset == 0 {
				xtramodes(g, r, &p.From)
			} else if p.To.Type == obj.TYPE_MEM && p.To.Offset == 0 {
				xtramodes(g, r, &p.To)
			} else {
				continue
			}
		}
	}

	//		case ACMP:
	//			/*
	//			 * elide CMP $0,x if calculation of x can set condition codes
	//			 */
	//			if(isdconst(&p->from) || p->from.offset != 0)
	//				continue;
	//			r2 = r->s1;
	//			if(r2 == nil)
	//				continue;
	//			t = r2->prog->as;
	//			switch(t) {
	//			default:
	//				continue;
	//			case ABEQ:
	//			case ABNE:
	//			case ABMI:
	//			case ABPL:
	//				break;
	//			case ABGE:
	//				t = ABPL;
	//				break;
	//			case ABLT:
	//				t = ABMI;
	//				break;
	//			case ABHI:
	//				t = ABNE;
	//				break;
	//			case ABLS:
	//				t = ABEQ;
	//				break;
	//			}
	//			r1 = r;
	//			do
	//				r1 = uniqp(r1);
	//			while (r1 != nil && r1->prog->as == ANOP);
	//			if(r1 == nil)
	//				continue;
	//			p1 = r1->prog;
	//			if(p1->to.type != TYPE_REG)
	//				continue;
	//			if(p1->to.reg != p->reg)
	//			if(!(p1->as == AMOVW && p1->from.type == TYPE_REG && p1->from.reg == p->reg))
	//				continue;
	//
	//			switch(p1->as) {
	//			default:
	//				continue;
	//			case AMOVW:
	//				if(p1->from.type != TYPE_REG)
	//					continue;
	//			case AAND:
	//			case AEOR:
	//			case AORR:
	//			case ABIC:
	//			case AMVN:
	//			case ASUB:
	//			case ARSB:
	//			case AADD:
	//			case AADC:
	//			case ASBC:
	//			case ARSC:
	//				break;
	//			}
	//			p1->scond |= C_SBIT;
	//			r2->prog->as = t;
	//			excise(r);
	//			continue;

	//	predicate(g);

	gc.Flowend(g)
}
示例#10
0
文件: peep.go 项目: ckeyer/gosrc
/*
 * ASLL x,y,w
 * .. (not use w, not set x y w)
 * AXXX w,a,b (a != w)
 * .. (not use w)
 * (set w)
 * ----------- changed to
 * ..
 * AXXX (x<<y),a,b
 * ..
 */
func shiftprop(r *gc.Flow) bool {
	p := (*obj.Prog)(r.Prog)
	if p.To.Type != obj.TYPE_REG {
		if gc.Debug['P'] != 0 {
			fmt.Printf("\tBOTCH: result not reg; FAILURE\n")
		}
		return false
	}

	n := int(int(p.To.Reg))
	a := obj.Addr(obj.Addr{})
	if p.Reg != 0 && p.Reg != p.To.Reg {
		a.Type = obj.TYPE_REG
		a.Reg = p.Reg
	}

	if gc.Debug['P'] != 0 {
		fmt.Printf("shiftprop\n%v", p)
	}
	r1 := (*gc.Flow)(r)
	var p1 *obj.Prog
	for {
		/* find first use of shift result; abort if shift operands or result are changed */
		r1 = gc.Uniqs(r1)

		if r1 == nil {
			if gc.Debug['P'] != 0 {
				fmt.Printf("\tbranch; FAILURE\n")
			}
			return false
		}

		if gc.Uniqp(r1) == nil {
			if gc.Debug['P'] != 0 {
				fmt.Printf("\tmerge; FAILURE\n")
			}
			return false
		}

		p1 = r1.Prog
		if gc.Debug['P'] != 0 {
			fmt.Printf("\n%v", p1)
		}
		switch copyu(p1, &p.To, nil) {
		case 0: /* not used or set */
			if (p.From.Type == obj.TYPE_REG && copyu(p1, &p.From, nil) > 1) || (a.Type == obj.TYPE_REG && copyu(p1, &a, nil) > 1) {
				if gc.Debug['P'] != 0 {
					fmt.Printf("\targs modified; FAILURE\n")
				}
				return false
			}

			continue
		case 3: /* set, not used */
			{
				if gc.Debug['P'] != 0 {
					fmt.Printf("\tBOTCH: noref; FAILURE\n")
				}
				return false
			}
		}

		break
	}

	/* check whether substitution can be done */
	switch p1.As {
	default:
		if gc.Debug['P'] != 0 {
			fmt.Printf("\tnon-dpi; FAILURE\n")
		}
		return false

	case arm.AAND,
		arm.AEOR,
		arm.AADD,
		arm.AADC,
		arm.AORR,
		arm.ASUB,
		arm.ASBC,
		arm.ARSB,
		arm.ARSC:
		if int(p1.Reg) == n || (p1.Reg == 0 && p1.To.Type == obj.TYPE_REG && int(p1.To.Reg) == n) {
			if p1.From.Type != obj.TYPE_REG {
				if gc.Debug['P'] != 0 {
					fmt.Printf("\tcan't swap; FAILURE\n")
				}
				return false
			}

			p1.Reg = p1.From.Reg
			p1.From.Reg = int16(n)
			switch p1.As {
			case arm.ASUB:
				p1.As = arm.ARSB

			case arm.ARSB:
				p1.As = arm.ASUB

			case arm.ASBC:
				p1.As = arm.ARSC

			case arm.ARSC:
				p1.As = arm.ASBC
			}

			if gc.Debug['P'] != 0 {
				fmt.Printf("\t=>%v", p1)
			}
		}
		fallthrough

	case arm.ABIC,
		arm.ATST,
		arm.ACMP,
		arm.ACMN:
		if int(p1.Reg) == n {
			if gc.Debug['P'] != 0 {
				fmt.Printf("\tcan't swap; FAILURE\n")
			}
			return false
		}

		if p1.Reg == 0 && int(p1.To.Reg) == n {
			if gc.Debug['P'] != 0 {
				fmt.Printf("\tshift result used twice; FAILURE\n")
			}
			return false
		}

		//	case AMVN:
		if p1.From.Type == obj.TYPE_SHIFT {
			if gc.Debug['P'] != 0 {
				fmt.Printf("\tshift result used in shift; FAILURE\n")
			}
			return false
		}

		if p1.From.Type != obj.TYPE_REG || int(p1.From.Reg) != n {
			if gc.Debug['P'] != 0 {
				fmt.Printf("\tBOTCH: where is it used?; FAILURE\n")
			}
			return false
		}
	}

	/* check whether shift result is used subsequently */
	p2 := (*obj.Prog)(p1)

	if int(p1.To.Reg) != n {
		var p1 *obj.Prog
		for {
			r1 = gc.Uniqs(r1)
			if r1 == nil {
				if gc.Debug['P'] != 0 {
					fmt.Printf("\tinconclusive; FAILURE\n")
				}
				return false
			}

			p1 = r1.Prog
			if gc.Debug['P'] != 0 {
				fmt.Printf("\n%v", p1)
			}
			switch copyu(p1, &p.To, nil) {
			case 0: /* not used or set */
				continue

			case 3: /* set, not used */
				break

			default: /* used */
				if gc.Debug['P'] != 0 {
					fmt.Printf("\treused; FAILURE\n")
				}
				return false
			}

			break
		}
	}

	/* make the substitution */
	p2.From.Reg = 0

	o := int(int(p.Reg))
	if o == 0 {
		o = int(p.To.Reg)
	}
	o &= 15

	switch p.From.Type {
	case obj.TYPE_CONST:
		o |= int((p.From.Offset & 0x1f) << 7)

	case obj.TYPE_REG:
		o |= 1<<4 | (int(p.From.Reg)&15)<<8
	}

	switch p.As {
	case arm.ASLL:
		o |= 0 << 5

	case arm.ASRL:
		o |= 1 << 5

	case arm.ASRA:
		o |= 2 << 5
	}

	p2.From = obj.Addr{}
	p2.From.Type = obj.TYPE_SHIFT
	p2.From.Offset = int64(o)
	if gc.Debug['P'] != 0 {
		fmt.Printf("\t=>%v\tSUCCEED\n", p2)
	}
	return true
}
示例#11
0
文件: obj9.go 项目: ckeyer/gosrc
func preprocess(ctxt *obj.Link, cursym *obj.LSym) {
	// TODO(minux): add morestack short-cuts with small fixed frame-size.
	ctxt.Cursym = cursym

	if cursym.Text == nil || cursym.Text.Link == nil {
		return
	}

	p := cursym.Text
	textstksiz := p.To.Offset
	if textstksiz == -8 {
		// Compatibility hack.
		p.From3.Offset |= obj.NOFRAME
		textstksiz = 0
	}
	if textstksiz%8 != 0 {
		ctxt.Diag("frame size %d not a multiple of 8", textstksiz)
	}
	if p.From3.Offset&obj.NOFRAME != 0 {
		if textstksiz != 0 {
			ctxt.Diag("NOFRAME functions must have a frame size of 0, not %d", textstksiz)
		}
	}

	cursym.Args = p.To.Val.(int32)
	cursym.Locals = int32(textstksiz)

	/*
	 * find leaf subroutines
	 * strip NOPs
	 * expand RET
	 * expand BECOME pseudo
	 */
	if ctxt.Debugvlog != 0 {
		fmt.Fprintf(ctxt.Bso, "%5.2f noops\n", obj.Cputime())
	}
	ctxt.Bso.Flush()

	var q *obj.Prog
	var q1 *obj.Prog
	for p := cursym.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,
			ASTWCCC,
			AECIWX,
			AECOWX,
			AEIEIO,
			AICBI,
			AISYNC,
			ATLBIE,
			ATLBIEL,
			ASLBIA,
			ASLBIE,
			ASLBMFEE,
			ASLBMFEV,
			ASLBMTE,
			ADCBF,
			ADCBI,
			ADCBST,
			ADCBT,
			ADCBTST,
			ADCBZ,
			ASYNC,
			ATLBSYNC,
			APTESYNC,
			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:
			cursym.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 {
				for q1.As == obj.ANOP {
					q1 = q1.Link
					p.Pcond = q1
				}

				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:
			q1 = p.Link
			q.Link = q1 /* q is non-nop */
			q1.Mark |= p.Mark
			continue

		default:
			q = p
			continue
		}
	}

	autosize := int32(0)
	var aoffset int
	var mov int
	var o int
	var p1 *obj.Prog
	var p2 *obj.Prog
	for p := cursym.Text; p != nil; p = p.Link {
		o = int(p.As)
		switch o {
		case obj.ATEXT:
			mov = AMOVD
			aoffset = 0
			autosize = int32(textstksiz)

			if p.Mark&LEAF != 0 && autosize == 0 && p.From3.Offset&obj.NOFRAME == 0 {
				// A leaf function with no locals has no frame.
				p.From3.Offset |= obj.NOFRAME
			}

			if p.From3.Offset&obj.NOFRAME == 0 {
				// If there is a stack frame at all, it includes
				// space to save the LR.
				autosize += int32(ctxt.FixedFrameSize())
			}

			p.To.Offset = int64(autosize)

			q = p

			if ctxt.Flag_shared != 0 && cursym.Name != "runtime.duffzero" && cursym.Name != "runtime.duffcopy" && cursym.Name != "runtime.stackBarrier" {
				// 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, and stackBarrier is only
				// ever called from an overwritten LR-save slot on the
				// stack (when r12 will not be remotely the right thing)
				// but fortunately does not access global data.
				//
				// 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.
				q = obj.Appendp(ctxt, q)
				q.As = AWORD
				q.Lineno = p.Lineno
				q.From.Type = obj.TYPE_CONST
				q.From.Offset = 0x3c4c0000
				q = obj.Appendp(ctxt, q)
				q.As = AWORD
				q.Lineno = p.Lineno
				q.From.Type = obj.TYPE_CONST
				q.From.Offset = 0x38420000
				rel := obj.Addrel(ctxt.Cursym)
				rel.Off = 0
				rel.Siz = 8
				rel.Sym = obj.Linklookup(ctxt, ".TOC.", 0)
				rel.Type = obj.R_ADDRPOWER_PCREL
			}

			if cursym.Text.From3.Offset&obj.NOSPLIT == 0 {
				q = stacksplit(ctxt, q, autosize) // emit split check
			}

			if autosize != 0 {
				/* use MOVDU to adjust R1 when saving R31, if autosize is small */
				if cursym.Text.Mark&LEAF == 0 && autosize >= -BIG && autosize <= BIG {
					mov = AMOVDU
					aoffset = int(-autosize)
				} else {
					q = obj.Appendp(ctxt, q)
					q.As = AADD
					q.Lineno = p.Lineno
					q.From.Type = obj.TYPE_CONST
					q.From.Offset = int64(-autosize)
					q.To.Type = obj.TYPE_REG
					q.To.Reg = REGSP
					q.Spadj = +autosize
				}
			} else if cursym.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.
				cursym.Text.Mark |= LEAF
			}

			if cursym.Text.Mark&LEAF != 0 {
				cursym.Leaf = 1
				break
			}

			q = obj.Appendp(ctxt, q)
			q.As = AMOVD
			q.Lineno = p.Lineno
			q.From.Type = obj.TYPE_REG
			q.From.Reg = REG_LR
			q.To.Type = obj.TYPE_REG
			q.To.Reg = REGTMP

			q = obj.Appendp(ctxt, q)
			q.As = int16(mov)
			q.Lineno = p.Lineno
			q.From.Type = obj.TYPE_REG
			q.From.Reg = REGTMP
			q.To.Type = obj.TYPE_MEM
			q.To.Offset = int64(aoffset)
			q.To.Reg = REGSP
			if q.As == AMOVDU {
				q.Spadj = int32(-aoffset)
			}

			if ctxt.Flag_shared != 0 {
				q = obj.Appendp(ctxt, q)
				q.As = AMOVD
				q.Lineno = p.Lineno
				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 cursym.Text.From3.Offset&obj.WRAPPER != 0 {
				// 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(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_R3

				q = obj.Appendp(ctxt, q)
				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(ctxt, q)
				q.As = ABEQ
				q.To.Type = obj.TYPE_BRANCH
				p1 = q

				q = obj.Appendp(ctxt, q)
				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(ctxt, q)
				q.As = AADD
				q.From.Type = obj.TYPE_CONST
				q.From.Offset = int64(autosize) + ctxt.FixedFrameSize()
				q.Reg = REGSP
				q.To.Type = obj.TYPE_REG
				q.To.Reg = REG_R5

				q = obj.Appendp(ctxt, q)
				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(ctxt, q)
				q.As = ABNE
				q.To.Type = obj.TYPE_BRANCH
				p2 = q

				q = obj.Appendp(ctxt, q)
				q.As = AADD
				q.From.Type = obj.TYPE_CONST
				q.From.Offset = ctxt.FixedFrameSize()
				q.Reg = REGSP
				q.To.Type = obj.TYPE_REG
				q.To.Reg = REG_R6

				q = obj.Appendp(ctxt, q)
				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(ctxt, q)

				q.As = obj.ANOP
				p1.Pcond = q
				p2.Pcond = q
			}

		case obj.ARET:
			if p.From.Type == obj.TYPE_CONST {
				ctxt.Diag("using BECOME (%v) is not supported!", p)
				break
			}

			retTarget := p.To.Sym

			if cursym.Text.Mark&LEAF != 0 {
				if autosize == 0 {
					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 = ctxt.NewProg()
				q.As = ABR
				q.Lineno = p.Lineno
				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 = ctxt.NewProg()
			q.As = AMOVD
			q.Lineno = p.Lineno
			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 = ctxt.NewProg()

				q.As = AMOVD
				q.Lineno = p.Lineno
				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
			}

			if autosize != 0 {
				q = ctxt.NewProg()
				q.As = AADD
				q.Lineno = p.Lineno
				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
				p.Link = q
			}

			q1 = ctxt.NewProg()
			q1.As = ABR
			q1.Lineno = p.Lineno
			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
			q.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)
			}
		}
	}
}
示例#12
0
文件: peep.go 项目: ckeyer/gosrc
/*
 * return
 * 1 if v only used (and substitute),
 * 2 if read-alter-rewrite
 * 3 if set
 * 4 if set and used
 * 0 otherwise (not touched)
 */
func copyu(p *obj.Prog, v *obj.Addr, s *obj.Addr) int {
	switch p.As {
	default:
		fmt.Printf("copyu: can't find %v\n", obj.Aconv(int(p.As)))
		return 2

	case arm.AMOVM:
		if v.Type != obj.TYPE_REG {
			return 0
		}
		if p.From.Type == obj.TYPE_CONST { /* read reglist, read/rar */
			if s != nil {
				if p.From.Offset&(1<<uint(v.Reg)) != 0 {
					return 1
				}
				if copysub(&p.To, v, s, 1) != 0 {
					return 1
				}
				return 0
			}

			if copyau(&p.To, v) {
				if p.Scond&arm.C_WBIT != 0 {
					return 2
				}
				return 1
			}

			if p.From.Offset&(1<<uint(v.Reg)) != 0 {
				return 1 /* read/rar, write reglist */
			}
		} else {
			if s != nil {
				if p.To.Offset&(1<<uint(v.Reg)) != 0 {
					return 1
				}
				if copysub(&p.From, v, s, 1) != 0 {
					return 1
				}
				return 0
			}

			if copyau(&p.From, v) {
				if p.Scond&arm.C_WBIT != 0 {
					return 2
				}
				if p.To.Offset&(1<<uint(v.Reg)) != 0 {
					return 4
				}
				return 1
			}

			if p.To.Offset&(1<<uint(v.Reg)) != 0 {
				return 3
			}
		}

		return 0

	case obj.ANOP, /* read,, write */
		arm.ASQRTD,
		arm.AMOVW,
		arm.AMOVF,
		arm.AMOVD,
		arm.AMOVH,
		arm.AMOVHS,
		arm.AMOVHU,
		arm.AMOVB,
		arm.AMOVBS,
		arm.AMOVBU,
		arm.AMOVFW,
		arm.AMOVWF,
		arm.AMOVDW,
		arm.AMOVWD,
		arm.AMOVFD,
		arm.AMOVDF:
		if p.Scond&(arm.C_WBIT|arm.C_PBIT) != 0 {
			if v.Type == obj.TYPE_REG {
				if p.From.Type == obj.TYPE_MEM || p.From.Type == obj.TYPE_SHIFT {
					if p.From.Reg == v.Reg {
						return 2
					}
				} else {
					if p.To.Reg == v.Reg {
						return 2
					}
				}
			}
		}

		if s != nil {
			if copysub(&p.From, v, s, 1) != 0 {
				return 1
			}
			if !copyas(&p.To, v) {
				if copysub(&p.To, v, s, 1) != 0 {
					return 1
				}
			}
			return 0
		}

		if copyas(&p.To, v) {
			if p.Scond != arm.C_SCOND_NONE {
				return 2
			}
			if copyau(&p.From, v) {
				return 4
			}
			return 3
		}

		if copyau(&p.From, v) {
			return 1
		}
		if copyau(&p.To, v) {
			return 1
		}
		return 0

	case arm.AMULLU, /* read, read, write, write */
		arm.AMULL,
		arm.AMULA,
		arm.AMVN:
		return 2

	case arm.AADD, /* read, read, write */
		arm.AADC,
		arm.ASUB,
		arm.ASBC,
		arm.ARSB,
		arm.ASLL,
		arm.ASRL,
		arm.ASRA,
		arm.AORR,
		arm.AAND,
		arm.AEOR,
		arm.AMUL,
		arm.AMULU,
		arm.ADIV,
		arm.ADIVU,
		arm.AMOD,
		arm.AMODU,
		arm.AADDF,
		arm.AADDD,
		arm.ASUBF,
		arm.ASUBD,
		arm.AMULF,
		arm.AMULD,
		arm.ADIVF,
		arm.ADIVD,
		obj.ACHECKNIL,
		/* read */
		arm.ACMPF, /* read, read, */
		arm.ACMPD,
		arm.ACMP,
		arm.ACMN,
		arm.ATST:
		/* read,, */
		if s != nil {
			if copysub(&p.From, v, s, 1) != 0 {
				return 1
			}
			if copysub1(p, v, s, 1) != 0 {
				return 1
			}
			if !copyas(&p.To, v) {
				if copysub(&p.To, v, s, 1) != 0 {
					return 1
				}
			}
			return 0
		}

		if copyas(&p.To, v) {
			if p.Scond != arm.C_SCOND_NONE {
				return 2
			}
			if p.Reg == 0 {
				p.Reg = p.To.Reg
			}
			if copyau(&p.From, v) {
				return 4
			}
			if copyau1(p, v) {
				return 4
			}
			return 3
		}

		if copyau(&p.From, v) {
			return 1
		}
		if copyau1(p, v) {
			return 1
		}
		if copyau(&p.To, v) {
			return 1
		}
		return 0

	case arm.ABEQ, /* read, read */
		arm.ABNE,
		arm.ABCS,
		arm.ABHS,
		arm.ABCC,
		arm.ABLO,
		arm.ABMI,
		arm.ABPL,
		arm.ABVS,
		arm.ABVC,
		arm.ABHI,
		arm.ABLS,
		arm.ABGE,
		arm.ABLT,
		arm.ABGT,
		arm.ABLE:
		if s != nil {
			if copysub(&p.From, v, s, 1) != 0 {
				return 1
			}
			return copysub1(p, v, s, 1)
		}

		if copyau(&p.From, v) {
			return 1
		}
		if copyau1(p, v) {
			return 1
		}
		return 0

	case arm.AB: /* funny */
		if s != nil {
			if copysub(&p.To, v, s, 1) != 0 {
				return 1
			}
			return 0
		}

		if copyau(&p.To, v) {
			return 1
		}
		return 0

	case obj.ARET: /* funny */
		if s != nil {
			return 1
		}
		return 3

	case arm.ABL: /* funny */
		if v.Type == obj.TYPE_REG {
			// TODO(rsc): REG_R0 and REG_F0 used to be
			// (when register numbers started at 0) exregoffset and exfregoffset,
			// which are unset entirely.
			// It's strange that this handles R0 and F0 differently from the other
			// registers. Possible failure to optimize?
			if arm.REG_R0 < v.Reg && v.Reg <= arm.REGEXT {
				return 2
			}
			if v.Reg == arm.REGARG {
				return 2
			}
			if arm.REG_F0 < v.Reg && v.Reg <= arm.FREGEXT {
				return 2
			}
		}

		if p.From.Type == obj.TYPE_REG && v.Type == obj.TYPE_REG && p.From.Reg == v.Reg {
			return 2
		}

		if s != nil {
			if copysub(&p.To, v, s, 1) != 0 {
				return 1
			}
			return 0
		}

		if copyau(&p.To, v) {
			return 4
		}
		return 3

		// R0 is zero, used by DUFFZERO, cannot be substituted.
	// R1 is ptr to memory, used and set, cannot be substituted.
	case obj.ADUFFZERO:
		if v.Type == obj.TYPE_REG {
			if v.Reg == arm.REG_R0 {
				return 1
			}
			if v.Reg == arm.REG_R0+1 {
				return 2
			}
		}

		return 0

		// R0 is scratch, set by DUFFCOPY, cannot be substituted.
	// R1, R2 areptr to src, dst, used and set, cannot be substituted.
	case obj.ADUFFCOPY:
		if v.Type == obj.TYPE_REG {
			if v.Reg == arm.REG_R0 {
				return 3
			}
			if v.Reg == arm.REG_R0+1 || v.Reg == arm.REG_R0+2 {
				return 2
			}
		}

		return 0

	case obj.ATEXT: /* funny */
		if v.Type == obj.TYPE_REG {
			if v.Reg == arm.REGARG {
				return 3
			}
		}
		return 0

	case obj.APCDATA,
		obj.AFUNCDATA,
		obj.AVARDEF,
		obj.AVARKILL,
		obj.AVARLIVE,
		obj.AUSEFIELD:
		return 0
	}
}
示例#13
0
文件: peep.go 项目: ckeyer/gosrc
// If s==nil, copyu returns the set/use of v in p; otherwise, it
// modifies p to replace reads of v with reads of s and returns 0 for
// success or non-zero for failure.
//
// If s==nil, copy returns one of the following values:
//	1 if v only used
//	2 if v is set and used in one address (read-alter-rewrite;
//	  can't substitute)
//	3 if v is only set
//	4 if v is set in one address and used in another (so addresses
//	  can be rewritten independently)
//	0 otherwise (not touched)
func copyu(p *obj.Prog, v *obj.Addr, s *obj.Addr) int {
	if p.From3Type() != obj.TYPE_NONE {
		// 7g never generates a from3
		fmt.Printf("copyu: from3 (%v) not implemented\n", gc.Ctxt.Dconv(p.From3))
	}
	if p.RegTo2 != obj.REG_NONE {
		// 7g never generates a to2
		fmt.Printf("copyu: RegTo2 (%v) not implemented\n", obj.Rconv(int(p.RegTo2)))
	}

	switch p.As {
	default:
		fmt.Printf("copyu: can't find %v\n", obj.Aconv(int(p.As)))
		return 2

	case obj.ANOP, /* read p->from, write p->to */
		arm64.ANEG,
		arm64.AFNEGD,
		arm64.AFNEGS,
		arm64.AFSQRTD,
		arm64.AFCVTZSD,
		arm64.AFCVTZSS,
		arm64.AFCVTZSDW,
		arm64.AFCVTZSSW,
		arm64.AFCVTZUD,
		arm64.AFCVTZUS,
		arm64.AFCVTZUDW,
		arm64.AFCVTZUSW,
		arm64.AFCVTSD,
		arm64.AFCVTDS,
		arm64.ASCVTFD,
		arm64.ASCVTFS,
		arm64.ASCVTFWD,
		arm64.ASCVTFWS,
		arm64.AUCVTFD,
		arm64.AUCVTFS,
		arm64.AUCVTFWD,
		arm64.AUCVTFWS,
		arm64.AMOVB,
		arm64.AMOVBU,
		arm64.AMOVH,
		arm64.AMOVHU,
		arm64.AMOVW,
		arm64.AMOVWU,
		arm64.AMOVD,
		arm64.AFMOVS,
		arm64.AFMOVD:
		if p.Scond == 0 {
			if s != nil {
				if copysub(&p.From, v, s, 1) != 0 {
					return 1
				}

				// Update only indirect uses of v in p->to
				if !copyas(&p.To, v) {
					if copysub(&p.To, v, s, 1) != 0 {
						return 1
					}
				}
				return 0
			}

			if copyas(&p.To, v) {
				// Fix up implicit from
				if p.From.Type == obj.TYPE_NONE {
					p.From = p.To
				}
				if copyau(&p.From, v) {
					return 4
				}
				return 3
			}

			if copyau(&p.From, v) {
				return 1
			}
			if copyau(&p.To, v) {
				// p->to only indirectly uses v
				return 1
			}

			return 0
		}

		/* rar p->from, write p->to or read p->from, rar p->to */
		if p.From.Type == obj.TYPE_MEM {
			if copyas(&p.From, v) {
				// No s!=nil check; need to fail
				// anyway in that case
				return 2
			}

			if s != nil {
				if copysub(&p.To, v, s, 1) != 0 {
					return 1
				}
				return 0
			}

			if copyas(&p.To, v) {
				return 3
			}
		} else if p.To.Type == obj.TYPE_MEM {
			if copyas(&p.To, v) {
				return 2
			}
			if s != nil {
				if copysub(&p.From, v, s, 1) != 0 {
					return 1
				}
				return 0
			}

			if copyau(&p.From, v) {
				return 1
			}
		} else {
			fmt.Printf("copyu: bad %v\n", p)
		}

		return 0

	case arm64.AADD, /* read p->from, read p->reg, write p->to */
		arm64.ASUB,
		arm64.AAND,
		arm64.AORR,
		arm64.AEOR,
		arm64.AMUL,
		arm64.ASMULL,
		arm64.AUMULL,
		arm64.ASMULH,
		arm64.AUMULH,
		arm64.ASDIV,
		arm64.AUDIV,
		arm64.ALSL,
		arm64.ALSR,
		arm64.AASR,
		arm64.AFADDD,
		arm64.AFADDS,
		arm64.AFSUBD,
		arm64.AFSUBS,
		arm64.AFMULD,
		arm64.AFMULS,
		arm64.AFDIVD,
		arm64.AFDIVS:
		if s != nil {
			if copysub(&p.From, v, s, 1) != 0 {
				return 1
			}
			if copysub1(p, v, s, 1) != 0 {
				return 1
			}

			// Update only indirect uses of v in p->to
			if !copyas(&p.To, v) {
				if copysub(&p.To, v, s, 1) != 0 {
					return 1
				}
			}
			return 0
		}

		if copyas(&p.To, v) {
			if p.Reg == 0 {
				// Fix up implicit reg (e.g., ADD
				// R3,R4 -> ADD R3,R4,R4) so we can
				// update reg and to separately.
				p.Reg = p.To.Reg
			}

			if copyau(&p.From, v) {
				return 4
			}
			if copyau1(p, v) {
				return 4
			}
			return 3
		}

		if copyau(&p.From, v) {
			return 1
		}
		if copyau1(p, v) {
			return 1
		}
		if copyau(&p.To, v) {
			return 1
		}
		return 0

	case arm64.ABEQ,
		arm64.ABNE,
		arm64.ABGE,
		arm64.ABLT,
		arm64.ABGT,
		arm64.ABLE,
		arm64.ABLO,
		arm64.ABLS,
		arm64.ABHI,
		arm64.ABHS:
		return 0

	case obj.ACHECKNIL, /* read p->from */
		arm64.ACMP, /* read p->from, read p->reg */
		arm64.AFCMPD,
		arm64.AFCMPS:
		if s != nil {
			if copysub(&p.From, v, s, 1) != 0 {
				return 1
			}
			return copysub1(p, v, s, 1)
		}

		if copyau(&p.From, v) {
			return 1
		}
		if copyau1(p, v) {
			return 1
		}
		return 0

	case arm64.AB: /* read p->to */
		if s != nil {
			if copysub(&p.To, v, s, 1) != 0 {
				return 1
			}
			return 0
		}

		if copyau(&p.To, v) {
			return 1
		}
		return 0

	case obj.ARET: /* funny */
		if s != nil {
			return 0
		}

		// All registers die at this point, so claim
		// everything is set (and not used).
		return 3

	case arm64.ABL: /* funny */
		if p.From.Type == obj.TYPE_REG && v.Type == obj.TYPE_REG && p.From.Reg == v.Reg {
			return 2
		}

		if s != nil {
			if copysub(&p.To, v, s, 1) != 0 {
				return 1
			}
			return 0
		}

		if copyau(&p.To, v) {
			return 4
		}
		return 3

	// R31 is zero, used by DUFFZERO, cannot be substituted.
	// R16 is ptr to memory, used and set, cannot be substituted.
	case obj.ADUFFZERO:
		if v.Type == obj.TYPE_REG {
			if v.Reg == 31 {
				return 1
			}
			if v.Reg == 16 {
				return 2
			}
		}

		return 0

	// R16, R17 are ptr to src, dst, used and set, cannot be substituted.
	// R27 is scratch, set by DUFFCOPY, cannot be substituted.
	case obj.ADUFFCOPY:
		if v.Type == obj.TYPE_REG {
			if v.Reg == 16 || v.Reg == 17 {
				return 2
			}
			if v.Reg == 27 {
				return 3
			}
		}

		return 0

	case arm64.AHINT,
		obj.ATEXT,
		obj.APCDATA,
		obj.AFUNCDATA,
		obj.AVARDEF,
		obj.AVARKILL,
		obj.AVARLIVE,
		obj.AUSEFIELD:
		return 0
	}
}
示例#14
0
文件: obj9.go 项目: ckeyer/gosrc
/*
// 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 stacksplit(ctxt *obj.Link, p *obj.Prog, framesize int32) *obj.Prog {
	// MOVD	g_stackguard(g), R3
	p = obj.Appendp(ctxt, p)

	p.As = AMOVD
	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_R3

	var q *obj.Prog
	if framesize <= obj.StackSmall {
		// small stack: SP < stackguard
		//	CMP	stackguard, SP
		p = obj.Appendp(ctxt, p)

		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 <= obj.StackBig {
		// large stack: SP-framesize < stackguard-StackSmall
		//	ADD $-framesize, SP, R4
		//	CMP stackguard, R4
		p = obj.Appendp(ctxt, p)

		p.As = AADD
		p.From.Type = obj.TYPE_CONST
		p.From.Offset = int64(-framesize)
		p.Reg = REGSP
		p.To.Type = obj.TYPE_REG
		p.To.Reg = REG_R4

		p = obj.Appendp(ctxt, p)
		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(ctxt, p)

		p.As = ACMP
		p.From.Type = obj.TYPE_REG
		p.From.Reg = REG_R3
		p.To.Type = obj.TYPE_CONST
		p.To.Offset = obj.StackPreempt

		p = obj.Appendp(ctxt, p)
		q = p
		p.As = ABEQ
		p.To.Type = obj.TYPE_BRANCH

		p = obj.Appendp(ctxt, p)
		p.As = AADD
		p.From.Type = obj.TYPE_CONST
		p.From.Offset = obj.StackGuard
		p.Reg = REGSP
		p.To.Type = obj.TYPE_REG
		p.To.Reg = REG_R4

		p = obj.Appendp(ctxt, p)
		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(ctxt, p)
		p.As = AMOVD
		p.From.Type = obj.TYPE_CONST
		p.From.Offset = int64(framesize) + obj.StackGuard - obj.StackSmall
		p.To.Type = obj.TYPE_REG
		p.To.Reg = REGTMP

		p = obj.Appendp(ctxt, p)
		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(ctxt, p)
	q1 := p

	p.As = ABLT
	p.To.Type = obj.TYPE_BRANCH

	// MOVD	LR, R5
	p = obj.Appendp(ctxt, p)

	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
	}

	var morestacksym *obj.LSym
	if ctxt.Cursym.Cfunc != 0 {
		morestacksym = obj.Linklookup(ctxt, "runtime.morestackc", 0)
	} else if ctxt.Cursym.Text.From3.Offset&obj.NEEDCTXT == 0 {
		morestacksym = obj.Linklookup(ctxt, "runtime.morestack_noctxt", 0)
	} else {
		morestacksym = obj.Linklookup(ctxt, "runtime.morestack", 0)
	}

	if 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(ctxt, p)
		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, CTR
		p = obj.Appendp(ctxt, p)
		p.As = AMOVD
		p.From.Type = obj.TYPE_REG
		p.From.Reg = REG_R12
		p.To.Type = obj.TYPE_REG
		p.To.Reg = REG_CTR

		// BL CTR
		p = obj.Appendp(ctxt, p)
		p.As = obj.ACALL
		p.From.Type = obj.TYPE_REG
		p.From.Reg = REG_R12
		p.To.Type = obj.TYPE_REG
		p.To.Reg = REG_CTR
	} else {
		// BL	runtime.morestack(SB)
		p = obj.Appendp(ctxt, p)

		p.As = ABL
		p.To.Type = obj.TYPE_BRANCH
		p.To.Sym = morestacksym
	}
	// BR	start
	p = obj.Appendp(ctxt, p)

	p.As = ABR
	p.To.Type = obj.TYPE_BRANCH
	p.Pcond = ctxt.Cursym.Text.Link

	// placeholder for q1's jump target
	p = obj.Appendp(ctxt, p)

	p.As = obj.ANOP // zero-width place holder
	q1.Pcond = p

	return p
}
示例#15
0
文件: peep.go 项目: ckeyer/gosrc
// If s==nil, copyu returns the set/use of v in p; otherwise, it
// modifies p to replace reads of v with reads of s and returns 0 for
// success or non-zero for failure.
//
// If s==nil, copy returns one of the following values:
// 	1 if v only used
//	2 if v is set and used in one address (read-alter-rewrite;
// 	  can't substitute)
//	3 if v is only set
//	4 if v is set in one address and used in another (so addresses
// 	  can be rewritten independently)
//	0 otherwise (not touched)
func copyu(p *obj.Prog, v *obj.Addr, s *obj.Addr) int {
	if p.From3Type() != obj.TYPE_NONE {
		// 9g never generates a from3
		fmt.Printf("copyu: from3 (%v) not implemented\n", gc.Ctxt.Dconv(p.From3))
	}

	switch p.As {
	default:
		fmt.Printf("copyu: can't find %v\n", obj.Aconv(int(p.As)))
		return 2

	case obj.ANOP, /* read p->from, write p->to */
		ppc64.AMOVH,
		ppc64.AMOVHZ,
		ppc64.AMOVB,
		ppc64.AMOVBZ,
		ppc64.AMOVW,
		ppc64.AMOVWZ,
		ppc64.AMOVD,
		ppc64.ANEG,
		ppc64.ANEGCC,
		ppc64.AADDME,
		ppc64.AADDMECC,
		ppc64.AADDZE,
		ppc64.AADDZECC,
		ppc64.ASUBME,
		ppc64.ASUBMECC,
		ppc64.ASUBZE,
		ppc64.ASUBZECC,
		ppc64.AFCTIW,
		ppc64.AFCTIWZ,
		ppc64.AFCTID,
		ppc64.AFCTIDZ,
		ppc64.AFCFID,
		ppc64.AFCFIDCC,
		ppc64.AFMOVS,
		ppc64.AFMOVD,
		ppc64.AFRSP,
		ppc64.AFNEG,
		ppc64.AFNEGCC:
		if s != nil {
			if copysub(&p.From, v, s, 1) != 0 {
				return 1
			}

			// Update only indirect uses of v in p->to
			if !copyas(&p.To, v) {
				if copysub(&p.To, v, s, 1) != 0 {
					return 1
				}
			}
			return 0
		}

		if copyas(&p.To, v) {
			// Fix up implicit from
			if p.From.Type == obj.TYPE_NONE {
				p.From = p.To
			}
			if copyau(&p.From, v) {
				return 4
			}
			return 3
		}

		if copyau(&p.From, v) {
			return 1
		}
		if copyau(&p.To, v) {
			// p->to only indirectly uses v
			return 1
		}

		return 0

	case ppc64.AMOVBU, /* rar p->from, write p->to or read p->from, rar p->to */
		ppc64.AMOVBZU,
		ppc64.AMOVHU,
		ppc64.AMOVHZU,
		ppc64.AMOVWZU,
		ppc64.AMOVDU:
		if p.From.Type == obj.TYPE_MEM {
			if copyas(&p.From, v) {
				// No s!=nil check; need to fail
				// anyway in that case
				return 2
			}

			if s != nil {
				if copysub(&p.To, v, s, 1) != 0 {
					return 1
				}
				return 0
			}

			if copyas(&p.To, v) {
				return 3
			}
		} else if p.To.Type == obj.TYPE_MEM {
			if copyas(&p.To, v) {
				return 2
			}
			if s != nil {
				if copysub(&p.From, v, s, 1) != 0 {
					return 1
				}
				return 0
			}

			if copyau(&p.From, v) {
				return 1
			}
		} else {
			fmt.Printf("copyu: bad %v\n", p)
		}

		return 0

	case ppc64.ARLWMI, /* read p->from, read p->reg, rar p->to */
		ppc64.ARLWMICC:
		if copyas(&p.To, v) {
			return 2
		}
		fallthrough

		/* fall through */
	case ppc64.AADD,
		/* read p->from, read p->reg, write p->to */
		ppc64.AADDC,
		ppc64.AADDE,
		ppc64.ASUB,
		ppc64.ASLW,
		ppc64.ASRW,
		ppc64.ASRAW,
		ppc64.ASLD,
		ppc64.ASRD,
		ppc64.ASRAD,
		ppc64.AOR,
		ppc64.AORCC,
		ppc64.AORN,
		ppc64.AORNCC,
		ppc64.AAND,
		ppc64.AANDCC,
		ppc64.AANDN,
		ppc64.AANDNCC,
		ppc64.ANAND,
		ppc64.ANANDCC,
		ppc64.ANOR,
		ppc64.ANORCC,
		ppc64.AXOR,
		ppc64.AMULHW,
		ppc64.AMULHWU,
		ppc64.AMULLW,
		ppc64.AMULLD,
		ppc64.ADIVW,
		ppc64.ADIVD,
		ppc64.ADIVWU,
		ppc64.ADIVDU,
		ppc64.AREM,
		ppc64.AREMU,
		ppc64.AREMD,
		ppc64.AREMDU,
		ppc64.ARLWNM,
		ppc64.ARLWNMCC,
		ppc64.AFADDS,
		ppc64.AFADD,
		ppc64.AFSUBS,
		ppc64.AFSUB,
		ppc64.AFMULS,
		ppc64.AFMUL,
		ppc64.AFDIVS,
		ppc64.AFDIV:
		if s != nil {
			if copysub(&p.From, v, s, 1) != 0 {
				return 1
			}
			if copysub1(p, v, s, 1) != 0 {
				return 1
			}

			// Update only indirect uses of v in p->to
			if !copyas(&p.To, v) {
				if copysub(&p.To, v, s, 1) != 0 {
					return 1
				}
			}
			return 0
		}

		if copyas(&p.To, v) {
			if p.Reg == 0 {
				// Fix up implicit reg (e.g., ADD
				// R3,R4 -> ADD R3,R4,R4) so we can
				// update reg and to separately.
				p.Reg = p.To.Reg
			}

			if copyau(&p.From, v) {
				return 4
			}
			if copyau1(p, v) {
				return 4
			}
			return 3
		}

		if copyau(&p.From, v) {
			return 1
		}
		if copyau1(p, v) {
			return 1
		}
		if copyau(&p.To, v) {
			return 1
		}
		return 0

	case ppc64.ABEQ,
		ppc64.ABGT,
		ppc64.ABGE,
		ppc64.ABLT,
		ppc64.ABLE,
		ppc64.ABNE,
		ppc64.ABVC,
		ppc64.ABVS:
		return 0

	case obj.ACHECKNIL, /* read p->from */
		ppc64.ACMP, /* read p->from, read p->to */
		ppc64.ACMPU,
		ppc64.ACMPW,
		ppc64.ACMPWU,
		ppc64.AFCMPO,
		ppc64.AFCMPU:
		if s != nil {
			if copysub(&p.From, v, s, 1) != 0 {
				return 1
			}
			return copysub(&p.To, v, s, 1)
		}

		if copyau(&p.From, v) {
			return 1
		}
		if copyau(&p.To, v) {
			return 1
		}
		return 0

		// 9g never generates a branch to a GPR (this isn't
	// even a normal instruction; liblink turns it in to a
	// mov and a branch).
	case ppc64.ABR: /* read p->to */
		if s != nil {
			if copysub(&p.To, v, s, 1) != 0 {
				return 1
			}
			return 0
		}

		if copyau(&p.To, v) {
			return 1
		}
		return 0

	case obj.ARET: /* funny */
		if s != nil {
			return 0
		}

		// All registers die at this point, so claim
		// everything is set (and not used).
		return 3

	case ppc64.ABL: /* funny */
		if v.Type == obj.TYPE_REG {
			// TODO(rsc): REG_R0 and REG_F0 used to be
			// (when register numbers started at 0) exregoffset and exfregoffset,
			// which are unset entirely.
			// It's strange that this handles R0 and F0 differently from the other
			// registers. Possible failure to optimize?
			if ppc64.REG_R0 < v.Reg && v.Reg <= ppc64.REGEXT {
				return 2
			}
			if v.Reg == ppc64.REGARG {
				return 2
			}
			if ppc64.REG_F0 < v.Reg && v.Reg <= ppc64.FREGEXT {
				return 2
			}
		}

		if p.From.Type == obj.TYPE_REG && v.Type == obj.TYPE_REG && p.From.Reg == v.Reg {
			return 2
		}

		if s != nil {
			if copysub(&p.To, v, s, 1) != 0 {
				return 1
			}
			return 0
		}

		if copyau(&p.To, v) {
			return 4
		}
		return 3

		// R0 is zero, used by DUFFZERO, cannot be substituted.
	// R3 is ptr to memory, used and set, cannot be substituted.
	case obj.ADUFFZERO:
		if v.Type == obj.TYPE_REG {
			if v.Reg == 0 {
				return 1
			}
			if v.Reg == 3 {
				return 2
			}
		}

		return 0

		// R3, R4 are ptr to src, dst, used and set, cannot be substituted.
	// R5 is scratch, set by DUFFCOPY, cannot be substituted.
	case obj.ADUFFCOPY:
		if v.Type == obj.TYPE_REG {
			if v.Reg == 3 || v.Reg == 4 {
				return 2
			}
			if v.Reg == 5 {
				return 3
			}
		}

		return 0

	case obj.ATEXT: /* funny */
		if v.Type == obj.TYPE_REG {
			if v.Reg == ppc64.REGARG {
				return 3
			}
		}
		return 0

	case obj.APCDATA,
		obj.AFUNCDATA,
		obj.AVARDEF,
		obj.AVARKILL,
		obj.AVARLIVE,
		obj.AUSEFIELD:
		return 0
	}
}
示例#16
0
文件: obj0.go 项目: ckeyer/gosrc
func preprocess(ctxt *obj.Link, cursym *obj.LSym) {
	// TODO(minux): add morestack short-cuts with small fixed frame-size.
	ctxt.Cursym = cursym

	// a switch for enabling/disabling instruction scheduling
	nosched := true

	if cursym.Text == nil || cursym.Text.Link == nil {
		return
	}

	p := cursym.Text
	textstksiz := p.To.Offset

	cursym.Args = p.To.Val.(int32)
	cursym.Locals = int32(textstksiz)

	/*
	 * find leaf subroutines
	 * strip NOPs
	 * expand RET
	 * expand BECOME pseudo
	 */
	if ctxt.Debugvlog != 0 {
		fmt.Fprintf(ctxt.Bso, "%5.2f noops\n", obj.Cputime())
	}
	ctxt.Bso.Flush()

	var q *obj.Prog
	var q1 *obj.Prog
	for p := cursym.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
			}

		/* too hard, just leave alone */
		case AMOVW,
			AMOVV:
			q = p
			if p.To.Type == obj.TYPE_REG && p.To.Reg >= REG_SPECIAL {
				p.Mark |= LABEL | SYNC
				break
			}
			if p.From.Type == obj.TYPE_REG && p.From.Reg >= REG_SPECIAL {
				p.Mark |= LABEL | SYNC
			}

		/* too hard, just leave alone */
		case ASYSCALL,
			AWORD,
			ATLBWR,
			ATLBWI,
			ATLBP,
			ATLBR:
			q = p
			p.Mark |= LABEL | SYNC

		case ANOR:
			q = p
			if p.To.Type == obj.TYPE_REG {
				if p.To.Reg == REGZERO {
					p.Mark |= LABEL | SYNC
				}
			}

		case ABGEZAL,
			ABLTZAL,
			AJAL,
			obj.ADUFFZERO,
			obj.ADUFFCOPY:
			cursym.Text.Mark &^= LEAF
			fallthrough

		case AJMP,
			ABEQ,
			ABGEZ,
			ABGTZ,
			ABLEZ,
			ABLTZ,
			ABNE,
			ABFPT, ABFPF:
			if p.As == ABFPT || p.As == ABFPF {
				// We don't treat ABFPT and ABFPF as branches here,
				// so that we will always fill nop (0x0) in their
				// delay slot during assembly.
				// This is to workaround a kernel FPU emulator bug
				// where it uses the user stack to simulate the
				// instruction in the delay slot if it's not 0x0,
				// and somehow that leads to SIGSEGV when the kernel
				// jump to the stack.
				p.Mark |= SYNC
			} else {
				p.Mark |= BRANCH
			}
			q = p
			q1 = p.Pcond
			if q1 != nil {
				for q1.As == obj.ANOP {
					q1 = q1.Link
					p.Pcond = q1
				}

				if q1.Mark&LEAF == 0 {
					q1.Mark |= LABEL
				}
			}
			//else {
			//	p.Mark |= LABEL
			//}
			q1 = p.Link
			if q1 != nil {
				q1.Mark |= LABEL
			}
			continue

		case ARET:
			q = p
			if p.Link != nil {
				p.Link.Mark |= LABEL
			}
			continue

		case obj.ANOP:
			q1 = p.Link
			q.Link = q1 /* q is non-nop */
			q1.Mark |= p.Mark
			continue

		default:
			q = p
			continue
		}
	}

	autosize := int32(0)
	var o int
	var p1 *obj.Prog
	var p2 *obj.Prog
	for p := cursym.Text; p != nil; p = p.Link {
		o = int(p.As)
		switch o {
		case obj.ATEXT:
			autosize = int32(textstksiz + 8)
			if (p.Mark&LEAF != 0) && autosize <= 8 {
				autosize = 0
			} else if autosize&4 != 0 {
				autosize += 4
			}
			p.To.Offset = int64(autosize) - 8

			if p.From3.Offset&obj.NOSPLIT == 0 {
				p = stacksplit(ctxt, p, autosize) // emit split check
			}

			q = p

			if autosize != 0 {
				q = obj.Appendp(ctxt, p)
				q.As = AADDV
				q.Lineno = p.Lineno
				q.From.Type = obj.TYPE_CONST
				q.From.Offset = int64(-autosize)
				q.To.Type = obj.TYPE_REG
				q.To.Reg = REGSP
				q.Spadj = +autosize
			} else if cursym.Text.Mark&LEAF == 0 {
				if cursym.Text.From3.Offset&obj.NOSPLIT != 0 {
					if ctxt.Debugvlog != 0 {
						fmt.Fprintf(ctxt.Bso, "save suppressed in: %s\n", cursym.Name)
						ctxt.Bso.Flush()
					}

					cursym.Text.Mark |= LEAF
				}
			}

			if cursym.Text.Mark&LEAF != 0 {
				cursym.Leaf = 1
				break
			}

			q = obj.Appendp(ctxt, q)
			q.As = AMOVV
			q.Lineno = p.Lineno
			q.From.Type = obj.TYPE_REG
			q.From.Reg = REGLINK
			q.To.Type = obj.TYPE_MEM
			q.To.Offset = int64(0)
			q.To.Reg = REGSP

			if cursym.Text.From3.Offset&obj.WRAPPER != 0 {
				// if(g->panic != nil && g->panic->argp == FP) g->panic->argp = bottom-of-frame
				//
				//	MOVV	g_panic(g), R1
				//	BEQ		R1, end
				//	MOVV	panic_argp(R1), R2
				//	ADDV	$(autosize+8), R29, R3
				//	BNE		R2, R3, end
				//	ADDV	$8, R29, R2
				//	MOVV	R2, panic_argp(R1)
				// end:
				//	NOP
				//
				// The NOP is needed to give the jumps somewhere to land.
				// It is a liblink NOP, not an mips NOP: it encodes to 0 instruction bytes.

				q = obj.Appendp(ctxt, q)

				q.As = AMOVV
				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 = ABEQ
				q.From.Type = obj.TYPE_REG
				q.From.Reg = REG_R1
				q.To.Type = obj.TYPE_BRANCH
				q.Mark |= BRANCH
				p1 = q

				q = obj.Appendp(ctxt, q)
				q.As = AMOVV
				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 = AADDV
				q.From.Type = obj.TYPE_CONST
				q.From.Offset = int64(autosize) + 8
				q.Reg = REGSP
				q.To.Type = obj.TYPE_REG
				q.To.Reg = REG_R3

				q = obj.Appendp(ctxt, q)
				q.As = ABNE
				q.From.Type = obj.TYPE_REG
				q.From.Reg = REG_R2
				q.Reg = REG_R3
				q.To.Type = obj.TYPE_BRANCH
				q.Mark |= BRANCH
				p2 = q

				q = obj.Appendp(ctxt, q)
				q.As = AADDV
				q.From.Type = obj.TYPE_CONST
				q.From.Offset = 8
				q.Reg = REGSP
				q.To.Type = obj.TYPE_REG
				q.To.Reg = REG_R2

				q = obj.Appendp(ctxt, q)
				q.As = AMOVV
				q.From.Type = obj.TYPE_REG
				q.From.Reg = REG_R2
				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
				p1.Pcond = q
				p2.Pcond = q
			}

		case ARET:
			if p.From.Type == obj.TYPE_CONST {
				ctxt.Diag("using BECOME (%v) is not supported!", p)
				break
			}

			if p.To.Sym != nil { // retjmp
				p.As = AJMP
				p.To.Type = obj.TYPE_BRANCH
				break
			}

			if cursym.Text.Mark&LEAF != 0 {
				if autosize == 0 {
					p.As = AJMP
					p.From = obj.Addr{}
					p.To.Type = obj.TYPE_MEM
					p.To.Offset = 0
					p.To.Reg = REGLINK
					p.Mark |= BRANCH
					break
				}

				p.As = AADDV
				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 = ctxt.NewProg()
				q.As = AJMP
				q.Lineno = p.Lineno
				q.To.Type = obj.TYPE_MEM
				q.To.Offset = 0
				q.To.Reg = REGLINK
				q.Mark |= BRANCH
				q.Spadj = +autosize

				q.Link = p.Link
				p.Link = q
				break
			}

			p.As = AMOVV
			p.From.Type = obj.TYPE_MEM
			p.From.Offset = 0
			p.From.Reg = REGSP
			p.To.Type = obj.TYPE_REG
			p.To.Reg = REG_R4

			if false {
				// Debug bad returns
				q = ctxt.NewProg()

				q.As = AMOVV
				q.Lineno = p.Lineno
				q.From.Type = obj.TYPE_MEM
				q.From.Offset = 0
				q.From.Reg = REG_R4
				q.To.Type = obj.TYPE_REG
				q.To.Reg = REGTMP

				q.Link = p.Link
				p.Link = q
				p = q
			}

			if autosize != 0 {
				q = ctxt.NewProg()
				q.As = AADDV
				q.Lineno = p.Lineno
				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
				p.Link = q
			}

			q1 = ctxt.NewProg()
			q1.As = AJMP
			q1.Lineno = p.Lineno
			q1.To.Type = obj.TYPE_MEM
			q1.To.Offset = 0
			q1.To.Reg = REG_R4
			q1.Mark |= BRANCH
			q1.Spadj = +autosize

			q1.Link = q.Link
			q.Link = q1

		case AADDV,
			AADDVU:
			if p.To.Type == obj.TYPE_REG && p.To.Reg == REGSP && p.From.Type == obj.TYPE_CONST {
				p.Spadj = int32(-p.From.Offset)
			}
		}
	}

	if nosched {
		// if we don't do instruction scheduling, simply add
		// NOP after each branch instruction.
		for p = cursym.Text; p != nil; p = p.Link {
			if p.Mark&BRANCH != 0 {
				addnop(ctxt, p)
			}
		}
		return
	}

	// instruction scheduling
	q = nil          // p - 1
	q1 = cursym.Text // top of block
	o = 0            // count of instructions
	for p = cursym.Text; p != nil; p = p1 {
		p1 = p.Link
		o++
		if p.Mark&NOSCHED != 0 {
			if q1 != p {
				sched(ctxt, q1, q)
			}
			for ; p != nil; p = p.Link {
				if p.Mark&NOSCHED == 0 {
					break
				}
				q = p
			}
			p1 = p
			q1 = p
			o = 0
			continue
		}
		if p.Mark&(LABEL|SYNC) != 0 {
			if q1 != p {
				sched(ctxt, q1, q)
			}
			q1 = p
			o = 1
		}
		if p.Mark&(BRANCH|SYNC) != 0 {
			sched(ctxt, q1, p)
			q1 = p1
			o = 0
		}
		if o >= NSCHED {
			sched(ctxt, q1, p)
			q1 = p1
			o = 0
		}
		q = p
	}
}
示例#17
0
文件: obj0.go 项目: ckeyer/gosrc
func stacksplit(ctxt *obj.Link, p *obj.Prog, framesize int32) *obj.Prog {
	// MOVV	g_stackguard(g), R1
	p = obj.Appendp(ctxt, p)

	p.As = AMOVV
	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

	var q *obj.Prog
	if framesize <= obj.StackSmall {
		// small stack: SP < stackguard
		//	AGTU	SP, stackguard, R1
		p = obj.Appendp(ctxt, p)

		p.As = ASGTU
		p.From.Type = obj.TYPE_REG
		p.From.Reg = REGSP
		p.Reg = REG_R1
		p.To.Type = obj.TYPE_REG
		p.To.Reg = REG_R1
	} else if framesize <= obj.StackBig {
		// large stack: SP-framesize < stackguard-StackSmall
		//	ADDV	$-framesize, SP, R2
		//	SGTU	R2, stackguard, R1
		p = obj.Appendp(ctxt, p)

		p.As = AADDV
		p.From.Type = obj.TYPE_CONST
		p.From.Offset = int64(-framesize)
		p.Reg = REGSP
		p.To.Type = obj.TYPE_REG
		p.To.Reg = REG_R2

		p = obj.Appendp(ctxt, p)
		p.As = ASGTU
		p.From.Type = obj.TYPE_REG
		p.From.Reg = REG_R2
		p.Reg = REG_R1
		p.To.Type = obj.TYPE_REG
		p.To.Reg = REG_R1
	} 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 R1
		//	MOVV	$StackPreempt, R2
		//	BEQ	R1, R2, label-of-call-to-morestack
		//	ADDV	$StackGuard, SP, R2
		//	SUBVU	R1, R2
		//	MOVV	$(framesize+(StackGuard-StackSmall)), R1
		//	SGTU	R2, R1, R1
		p = obj.Appendp(ctxt, p)

		p.As = AMOVV
		p.From.Type = obj.TYPE_CONST
		p.From.Offset = obj.StackPreempt
		p.To.Type = obj.TYPE_REG
		p.To.Reg = REG_R2

		p = obj.Appendp(ctxt, p)
		q = p
		p.As = ABEQ
		p.From.Type = obj.TYPE_REG
		p.From.Reg = REG_R1
		p.Reg = REG_R2
		p.To.Type = obj.TYPE_BRANCH
		p.Mark |= BRANCH

		p = obj.Appendp(ctxt, p)
		p.As = AADDV
		p.From.Type = obj.TYPE_CONST
		p.From.Offset = obj.StackGuard
		p.Reg = REGSP
		p.To.Type = obj.TYPE_REG
		p.To.Reg = REG_R2

		p = obj.Appendp(ctxt, p)
		p.As = ASUBVU
		p.From.Type = obj.TYPE_REG
		p.From.Reg = REG_R1
		p.To.Type = obj.TYPE_REG
		p.To.Reg = REG_R2

		p = obj.Appendp(ctxt, p)
		p.As = AMOVV
		p.From.Type = obj.TYPE_CONST
		p.From.Offset = int64(framesize) + obj.StackGuard - obj.StackSmall
		p.To.Type = obj.TYPE_REG
		p.To.Reg = REG_R1

		p = obj.Appendp(ctxt, p)
		p.As = ASGTU
		p.From.Type = obj.TYPE_REG
		p.From.Reg = REG_R2
		p.Reg = REG_R1
		p.To.Type = obj.TYPE_REG
		p.To.Reg = REG_R1
	}

	// q1: BNE	R1, done
	p = obj.Appendp(ctxt, p)
	q1 := p

	p.As = ABNE
	p.From.Type = obj.TYPE_REG
	p.From.Reg = REG_R1
	p.To.Type = obj.TYPE_BRANCH
	p.Mark |= BRANCH

	// MOVV	LINK, R3
	p = obj.Appendp(ctxt, p)

	p.As = AMOVV
	p.From.Type = obj.TYPE_REG
	p.From.Reg = REGLINK
	p.To.Type = obj.TYPE_REG
	p.To.Reg = REG_R3
	if q != nil {
		q.Pcond = p
		p.Mark |= LABEL
	}

	// JAL	runtime.morestack(SB)
	p = obj.Appendp(ctxt, p)

	p.As = AJAL
	p.To.Type = obj.TYPE_BRANCH
	if ctxt.Cursym.Cfunc != 0 {
		p.To.Sym = obj.Linklookup(ctxt, "runtime.morestackc", 0)
	} else if ctxt.Cursym.Text.From3.Offset&obj.NEEDCTXT == 0 {
		p.To.Sym = obj.Linklookup(ctxt, "runtime.morestack_noctxt", 0)
	} else {
		p.To.Sym = obj.Linklookup(ctxt, "runtime.morestack", 0)
	}
	p.Mark |= BRANCH

	// JMP	start
	p = obj.Appendp(ctxt, p)

	p.As = AJMP
	p.To.Type = obj.TYPE_BRANCH
	p.Pcond = ctxt.Cursym.Text.Link
	p.Mark |= BRANCH

	// placeholder for q1's jump target
	p = obj.Appendp(ctxt, p)

	p.As = obj.ANOP // zero-width place holder
	q1.Pcond = p

	return p
}
示例#18
0
文件: obj5.go 项目: ckeyer/gosrc
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 {
	}

	spfix := obj.Appendp(ctxt, last)
	spfix.As = obj.ANOP
	spfix.Spadj = -framesize

	// MOVW	LR, R3
	movw := obj.Appendp(ctxt, spfix)
	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
	b.Spadj = +framesize

	return bls
}
示例#19
0
文件: obj7.go 项目: ckeyer/gosrc
func stacksplit(ctxt *obj.Link, p *obj.Prog, framesize int32) *obj.Prog {
	// MOV	g_stackguard(g), R1
	p = obj.Appendp(ctxt, p)

	p.As = AMOVD
	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

	q := (*obj.Prog)(nil)
	if framesize <= obj.StackSmall {
		// small stack: SP < stackguard
		//	MOV	SP, R2
		//	CMP	stackguard, R2
		p = obj.Appendp(ctxt, p)

		p.As = AMOVD
		p.From.Type = obj.TYPE_REG
		p.From.Reg = REGSP
		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 if framesize <= obj.StackBig {
		// large stack: SP-framesize < stackguard-StackSmall
		//	SUB	$framesize, SP, R2
		//	CMP	stackguard, R2
		p = obj.Appendp(ctxt, p)

		p.As = ASUB
		p.From.Type = obj.TYPE_CONST
		p.From.Offset = int64(framesize)
		p.Reg = REGSP
		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
		//	BEQ	label_of_call_to_morestack
		//	ADD	$StackGuard, SP, R2
		//	SUB	R1, R2
		//	MOV	$(framesize+(StackGuard-StackSmall)), R3
		//	CMP	R3, R2
		p = obj.Appendp(ctxt, p)

		p.As = ACMP
		p.From.Type = obj.TYPE_CONST
		p.From.Offset = obj.StackPreempt
		p.Reg = REG_R1

		p = obj.Appendp(ctxt, p)
		q = p
		p.As = ABEQ
		p.To.Type = obj.TYPE_BRANCH

		p = obj.Appendp(ctxt, p)
		p.As = AADD
		p.From.Type = obj.TYPE_CONST
		p.From.Offset = obj.StackGuard
		p.Reg = REGSP
		p.To.Type = obj.TYPE_REG
		p.To.Reg = REG_R2

		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 = obj.Appendp(ctxt, p)
		p.As = AMOVD
		p.From.Type = obj.TYPE_CONST
		p.From.Offset = int64(framesize) + (obj.StackGuard - obj.StackSmall)
		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_R3
		p.Reg = REG_R2
	}

	// BLS	do-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 {
	}

	spfix := obj.Appendp(ctxt, last)
	spfix.As = obj.ANOP
	spfix.Spadj = -framesize

	// MOV	LR, R3
	movlr := obj.Appendp(ctxt, spfix)
	movlr.As = AMOVD
	movlr.From.Type = obj.TYPE_REG
	movlr.From.Reg = REGLINK
	movlr.To.Type = obj.TYPE_REG
	movlr.To.Reg = REG_R3
	if q != nil {
		q.Pcond = movlr
	}
	bls.Pcond = movlr

	debug := movlr
	if false {
		debug = obj.Appendp(ctxt, debug)
		debug.As = AMOVD
		debug.From.Type = obj.TYPE_CONST
		debug.From.Offset = int64(framesize)
		debug.To.Type = obj.TYPE_REG
		debug.To.Reg = REGTMP
	}

	// BL	runtime.morestack(SB)
	call := obj.Appendp(ctxt, debug)
	call.As = ABL
	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
	jmp := obj.Appendp(ctxt, call)
	jmp.As = AB
	jmp.To.Type = obj.TYPE_BRANCH
	jmp.Pcond = ctxt.Cursym.Text.Link
	jmp.Spadj = +framesize

	// placeholder for bls's jump target
	// p = obj.Appendp(ctxt, p)
	// p.As = obj.ANOP

	return bls
}