Golang Fatal Examples, rsc/io/tmp/bootstrap/internal/gc.Fatal Golang Examples

Example #1

0

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File: ggen.go Project: rsc/tmp

func defframe(ptxt *obj.Prog) {
	var n *gc.Node

	// fill in argument size, stack size
	ptxt.To.Type = obj.TYPE_TEXTSIZE

	ptxt.To.Val = int32(gc.Rnd(gc.Curfn.Type.Argwid, int64(gc.Widthptr)))
	frame := uint32(gc.Rnd(gc.Stksize+gc.Maxarg, int64(gc.Widthreg)))
	ptxt.To.Offset = int64(frame)

	// insert code to zero ambiguously live variables
	// so that the garbage collector only sees initialized values
	// when it looks for pointers.
	p := ptxt

	hi := int64(0)
	lo := hi
	ax := uint32(0)

	// iterate through declarations - they are sorted in decreasing xoffset order.
	for l := gc.Curfn.Func.Dcl; l != nil; l = l.Next {
		n = l.N
		if !n.Needzero {
			continue
		}
		if n.Class != gc.PAUTO {
			gc.Fatal("needzero class %d", n.Class)
		}
		if n.Type.Width%int64(gc.Widthptr) != 0 || n.Xoffset%int64(gc.Widthptr) != 0 || n.Type.Width == 0 {
			gc.Fatal("var %v has size %d offset %d", gc.Nconv(n, obj.FmtLong), int(n.Type.Width), int(n.Xoffset))
		}

		if lo != hi && n.Xoffset+n.Type.Width >= lo-int64(2*gc.Widthreg) {
			// merge with range we already have
			lo = n.Xoffset

			continue
		}

		// zero old range
		p = zerorange(p, int64(frame), lo, hi, &ax)

		// set new range
		hi = n.Xoffset + n.Type.Width

		lo = n.Xoffset
	}

	// zero final range
	zerorange(p, int64(frame), lo, hi, &ax)
}

Example #2

0

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File: peep.go Project: rsc/tmp

/*
 * direct reference,
 * could be set/use depending on
 * semantics
 */
func copyas(a *obj.Addr, v *obj.Addr) bool {
	if x86.REG_AL <= a.Reg && a.Reg <= x86.REG_R15B {
		gc.Fatal("use of byte register")
	}
	if x86.REG_AL <= v.Reg && v.Reg <= x86.REG_R15B {
		gc.Fatal("use of byte register")
	}

	if a.Type != v.Type || a.Name != v.Name || a.Reg != v.Reg {
		return false
	}
	if regtyp(v) {
		return true
	}
	if v.Type == obj.TYPE_MEM && (v.Name == obj.NAME_AUTO || v.Name == obj.NAME_PARAM) {
		if v.Offset == a.Offset {
			return true
		}
	}
	return false
}

Example #3

0

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File: prog.go Project: rsc/tmp

func proginfo(p *obj.Prog) {
	info := &p.Info
	*info = progtable[p.As]
	if info.Flags == 0 {
		gc.Fatal("unknown instruction %v", p)
	}

	if (info.Flags&gc.ShiftCX != 0) && p.From.Type != obj.TYPE_CONST {
		info.Reguse |= CX
	}

	if info.Flags&gc.ImulAXDX != 0 {
		if p.To.Type == obj.TYPE_NONE {
			info.Reguse |= AX
			info.Regset |= AX | DX
		} else {
			info.Flags |= RightRdwr
		}
	}

	// Addressing makes some registers used.
	if p.From.Type == obj.TYPE_MEM && p.From.Name == obj.NAME_NONE {
		info.Regindex |= RtoB(int(p.From.Reg))
	}
	if p.From.Index != x86.REG_NONE {
		info.Regindex |= RtoB(int(p.From.Index))
	}
	if p.To.Type == obj.TYPE_MEM && p.To.Name == obj.NAME_NONE {
		info.Regindex |= RtoB(int(p.To.Reg))
	}
	if p.To.Index != x86.REG_NONE {
		info.Regindex |= RtoB(int(p.To.Index))
	}
	if gc.Ctxt.Flag_dynlink {
		// When -dynlink is passed, many operations on external names (and
		// also calling duffzero/duffcopy) use R15 as a scratch register.
		if p.As == x86.ALEAQ || info.Flags == gc.Pseudo || p.As == obj.ACALL || p.As == obj.ARET || p.As == obj.AJMP {
			return
		}
		if p.As == obj.ADUFFZERO || p.As == obj.ADUFFCOPY || (p.From.Name == obj.NAME_EXTERN && !p.From.Sym.Local) || (p.To.Name == obj.NAME_EXTERN && !p.To.Sym.Local) {
			info.Reguse |= R15
			info.Regset |= R15
			return
		}
	}
}

Example #4

0

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File: ggen.go Project: rsc/tmp

func zerorange(p *obj.Prog, frame int64, lo int64, hi int64, ax *uint32) *obj.Prog {
	cnt := hi - lo
	if cnt == 0 {
		return p
	}
	if *ax == 0 {
		p = appendpp(p, x86.AMOVQ, obj.TYPE_CONST, 0, 0, obj.TYPE_REG, x86.REG_AX, 0)
		*ax = 1
	}

	if cnt%int64(gc.Widthreg) != 0 {
		// should only happen with nacl
		if cnt%int64(gc.Widthptr) != 0 {
			gc.Fatal("zerorange count not a multiple of widthptr %d", cnt)
		}
		p = appendpp(p, x86.AMOVL, obj.TYPE_REG, x86.REG_AX, 0, obj.TYPE_MEM, x86.REG_SP, frame+lo)
		lo += int64(gc.Widthptr)
		cnt -= int64(gc.Widthptr)
	}

	if cnt <= int64(4*gc.Widthreg) {
		for i := int64(0); i < cnt; i += int64(gc.Widthreg) {
			p = appendpp(p, x86.AMOVQ, obj.TYPE_REG, x86.REG_AX, 0, obj.TYPE_MEM, x86.REG_SP, frame+lo+i)
		}
	} else if !gc.Nacl && (cnt <= int64(128*gc.Widthreg)) {
		q := cnt / int64(gc.Widthreg)
		p = appendpp(p, leaptr, obj.TYPE_MEM, x86.REG_SP, frame+lo+dzDI(q), obj.TYPE_REG, x86.REG_DI, 0)
		p = appendpp(p, obj.ADUFFZERO, obj.TYPE_NONE, 0, 0, obj.TYPE_ADDR, 0, dzOff(q))
		p.To.Sym = gc.Linksym(gc.Pkglookup("duffzero", gc.Runtimepkg))
	} else {
		p = appendpp(p, x86.AMOVQ, obj.TYPE_CONST, 0, cnt/int64(gc.Widthreg), obj.TYPE_REG, x86.REG_CX, 0)
		p = appendpp(p, leaptr, obj.TYPE_MEM, x86.REG_SP, frame+lo, obj.TYPE_REG, x86.REG_DI, 0)
		p = appendpp(p, x86.AREP, obj.TYPE_NONE, 0, 0, obj.TYPE_NONE, 0, 0)
		p = appendpp(p, x86.ASTOSQ, obj.TYPE_NONE, 0, 0, obj.TYPE_NONE, 0, 0)
	}

	return p
}

Example #5

0

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