/*
* generate:
* res = n;
* simplifies and calls gmove.
*/
func cgen(n *gc.Node, res *gc.Node) {
//print("cgen %N(%d) -> %N(%d)\n", n, n->addable, res, res->addable);
if gc.Debug['g'] != 0 {
gc.Dump("\ncgen-n", n)
gc.Dump("cgen-res", res)
}
if n == nil || n.Type == nil {
return
}
if res == nil || res.Type == nil {
gc.Fatal("cgen: res nil")
}
for n.Op == gc.OCONVNOP {
n = n.Left
}
switch n.Op {
case gc.OSLICE,
gc.OSLICEARR,
gc.OSLICESTR,
gc.OSLICE3,
gc.OSLICE3ARR:
if res.Op != gc.ONAME || res.Addable == 0 {
var n1 gc.Node
gc.Tempname(&n1, n.Type)
gc.Cgen_slice(n, &n1)
cgen(&n1, res)
} else {
gc.Cgen_slice(n, res)
}
return
case gc.OEFACE:
if res.Op != gc.ONAME || res.Addable == 0 {
var n1 gc.Node
gc.Tempname(&n1, n.Type)
gc.Cgen_eface(n, &n1)
cgen(&n1, res)
} else {
gc.Cgen_eface(n, res)
}
return
}
if n.Ullman >= gc.UINF {
if n.Op == gc.OINDREG {
gc.Fatal("cgen: this is going to misscompile")
}
if res.Ullman >= gc.UINF {
var n1 gc.Node
gc.Tempname(&n1, n.Type)
cgen(n, &n1)
cgen(&n1, res)
return
}
}
if gc.Isfat(n.Type) {
if n.Type.Width < 0 {
gc.Fatal("forgot to compute width for %v", gc.Tconv(n.Type, 0))
}
sgen(n, res, n.Type.Width)
return
}
if res.Addable == 0 {
if n.Ullman > res.Ullman {
var n1 gc.Node
regalloc(&n1, n.Type, res)
cgen(n, &n1)
if n1.Ullman > res.Ullman {
gc.Dump("n1", &n1)
gc.Dump("res", res)
gc.Fatal("loop in cgen")
}
cgen(&n1, res)
regfree(&n1)
return
}
var f int
if res.Ullman >= gc.UINF {
goto gen
}
if gc.Complexop(n, res) {
gc.Complexgen(n, res)
return
}
f = 1 // gen thru register
switch n.Op {
case gc.OLITERAL:
if gc.Smallintconst(n) {
f = 0
}
case gc.OREGISTER:
f = 0
}
if !gc.Iscomplex[n.Type.Etype] {
a := optoas(gc.OAS, res.Type)
var addr obj.Addr
if sudoaddable(a, res, &addr) {
var p1 *obj.Prog
if f != 0 {
var n2 gc.Node
regalloc(&n2, res.Type, nil)
cgen(n, &n2)
p1 = gins(a, &n2, nil)
regfree(&n2)
} else {
p1 = gins(a, n, nil)
}
p1.To = addr
if gc.Debug['g'] != 0 {
fmt.Printf("%v [ignore previous line]\n", p1)
}
sudoclean()
return
}
}
gen:
var n1 gc.Node
igen(res, &n1, nil)
cgen(n, &n1)
regfree(&n1)
return
}
// update addressability for string, slice
// can't do in walk because n->left->addable
// changes if n->left is an escaping local variable.
switch n.Op {
case gc.OSPTR,
gc.OLEN:
if gc.Isslice(n.Left.Type) || gc.Istype(n.Left.Type, gc.TSTRING) {
n.Addable = n.Left.Addable
}
case gc.OCAP:
if gc.Isslice(n.Left.Type) {
n.Addable = n.Left.Addable
}
case gc.OITAB:
n.Addable = n.Left.Addable
}
if gc.Complexop(n, res) {
gc.Complexgen(n, res)
return
}
// if both are addressable, move
if n.Addable != 0 {
if n.Op == gc.OREGISTER || res.Op == gc.OREGISTER {
gmove(n, res)
} else {
var n1 gc.Node
regalloc(&n1, n.Type, nil)
gmove(n, &n1)
cgen(&n1, res)
regfree(&n1)
}
return
}
nl := n.Left
nr := n.Right
if nl != nil && nl.Ullman >= gc.UINF {
if nr != nil && nr.Ullman >= gc.UINF {
var n1 gc.Node
gc.Tempname(&n1, nl.Type)
cgen(nl, &n1)
n2 := *n
n2.Left = &n1
cgen(&n2, res)
return
}
}
if !gc.Iscomplex[n.Type.Etype] {
a := optoas(gc.OAS, n.Type)
var addr obj.Addr
if sudoaddable(a, n, &addr) {
if res.Op == gc.OREGISTER {
p1 := gins(a, nil, res)
p1.From = addr
} else {
var n2 gc.Node
regalloc(&n2, n.Type, nil)
p1 := gins(a, nil, &n2)
p1.From = addr
gins(a, &n2, res)
regfree(&n2)
}
sudoclean()
return
}
}
// TODO(minux): we shouldn't reverse FP comparisons, but then we need to synthesize
// OGE, OLE, and ONE ourselves.
// if(nl != N && isfloat[n->type->etype] && isfloat[nl->type->etype]) goto flt;
var a int
switch n.Op {
default:
gc.Dump("cgen", n)
gc.Fatal("cgen: unknown op %v", gc.Nconv(n, obj.FmtShort|obj.FmtSign))
// these call bgen to get a bool value
case gc.OOROR,
gc.OANDAND,
gc.OEQ,
gc.ONE,
gc.OLT,
gc.OLE,
gc.OGE,
gc.OGT,
gc.ONOT:
p1 := gc.Gbranch(ppc64.ABR, nil, 0)
p2 := gc.Pc
gmove(gc.Nodbool(true), res)
p3 := gc.Gbranch(ppc64.ABR, nil, 0)
gc.Patch(p1, gc.Pc)
bgen(n, true, 0, p2)
gmove(gc.Nodbool(false), res)
gc.Patch(p3, gc.Pc)
return
case gc.OPLUS:
cgen(nl, res)
return
// unary
case gc.OCOM:
a := optoas(gc.OXOR, nl.Type)
var n1 gc.Node
regalloc(&n1, nl.Type, nil)
cgen(nl, &n1)
var n2 gc.Node
gc.Nodconst(&n2, nl.Type, -1)
gins(a, &n2, &n1)
gmove(&n1, res)
regfree(&n1)
return
case gc.OMINUS:
if gc.Isfloat[nl.Type.Etype] {
nr = gc.Nodintconst(-1)
gc.Convlit(&nr, n.Type)
a = optoas(gc.OMUL, nl.Type)
goto sbop
}
a := optoas(int(n.Op), nl.Type)
// unary
var n1 gc.Node
regalloc(&n1, nl.Type, res)
cgen(nl, &n1)
gins(a, nil, &n1)
gmove(&n1, res)
regfree(&n1)
return
// symmetric binary
case gc.OAND,
gc.OOR,
gc.OXOR,
gc.OADD,
gc.OMUL:
a = optoas(int(n.Op), nl.Type)
goto sbop
// asymmetric binary
case gc.OSUB:
a = optoas(int(n.Op), nl.Type)
goto abop
case gc.OHMUL:
cgen_hmul(nl, nr, res)
case gc.OCONV:
if n.Type.Width > nl.Type.Width {
// If loading from memory, do conversion during load,
// so as to avoid use of 8-bit register in, say, int(*byteptr).
switch nl.Op {
case gc.ODOT,
gc.ODOTPTR,
gc.OINDEX,
gc.OIND,
gc.ONAME:
var n1 gc.Node
igen(nl, &n1, res)
var n2 gc.Node
regalloc(&n2, n.Type, res)
gmove(&n1, &n2)
gmove(&n2, res)
regfree(&n2)
regfree(&n1)
return
}
}
var n1 gc.Node
regalloc(&n1, nl.Type, res)
var n2 gc.Node
regalloc(&n2, n.Type, &n1)
cgen(nl, &n1)
// if we do the conversion n1 -> n2 here
// reusing the register, then gmove won't
// have to allocate its own register.
gmove(&n1, &n2)
gmove(&n2, res)
regfree(&n2)
regfree(&n1)
case gc.ODOT,
gc.ODOTPTR,
gc.OINDEX,
gc.OIND,
gc.ONAME: // PHEAP or PPARAMREF var
var n1 gc.Node
igen(n, &n1, res)
gmove(&n1, res)
regfree(&n1)
// interface table is first word of interface value
case gc.OITAB:
var n1 gc.Node
igen(nl, &n1, res)
n1.Type = n.Type
gmove(&n1, res)
regfree(&n1)
// pointer is the first word of string or slice.
case gc.OSPTR:
if gc.Isconst(nl, gc.CTSTR) {
var n1 gc.Node
regalloc(&n1, gc.Types[gc.Tptr], res)
p1 := gins(ppc64.AMOVD, nil, &n1)
gc.Datastring(nl.Val.U.Sval, &p1.From)
gmove(&n1, res)
regfree(&n1)
break
}
var n1 gc.Node
igen(nl, &n1, res)
n1.Type = n.Type
gmove(&n1, res)
regfree(&n1)
case gc.OLEN:
if gc.Istype(nl.Type, gc.TMAP) || gc.Istype(nl.Type, gc.TCHAN) {
// map and chan have len in the first int-sized word.
// a zero pointer means zero length
var n1 gc.Node
regalloc(&n1, gc.Types[gc.Tptr], res)
cgen(nl, &n1)
var n2 gc.Node
gc.Nodconst(&n2, gc.Types[gc.Tptr], 0)
gins(optoas(gc.OCMP, gc.Types[gc.Tptr]), &n1, &n2)
p1 := gc.Gbranch(optoas(gc.OEQ, gc.Types[gc.Tptr]), nil, 0)
n2 = n1
n2.Op = gc.OINDREG
n2.Type = gc.Types[gc.Simtype[gc.TINT]]
gmove(&n2, &n1)
gc.Patch(p1, gc.Pc)
gmove(&n1, res)
regfree(&n1)
break
}
if gc.Istype(nl.Type, gc.TSTRING) || gc.Isslice(nl.Type) {
// both slice and string have len one pointer into the struct.
// a zero pointer means zero length
var n1 gc.Node
igen(nl, &n1, res)
n1.Type = gc.Types[gc.Simtype[gc.TUINT]]
n1.Xoffset += int64(gc.Array_nel)
gmove(&n1, res)
regfree(&n1)
break
}
gc.Fatal("cgen: OLEN: unknown type %v", gc.Tconv(nl.Type, obj.FmtLong))
case gc.OCAP:
if gc.Istype(nl.Type, gc.TCHAN) {
// chan has cap in the second int-sized word.
// a zero pointer means zero length
var n1 gc.Node
regalloc(&n1, gc.Types[gc.Tptr], res)
cgen(nl, &n1)
var n2 gc.Node
gc.Nodconst(&n2, gc.Types[gc.Tptr], 0)
gins(optoas(gc.OCMP, gc.Types[gc.Tptr]), &n1, &n2)
p1 := gc.Gbranch(optoas(gc.OEQ, gc.Types[gc.Tptr]), nil, 0)
n2 = n1
n2.Op = gc.OINDREG
n2.Xoffset = int64(gc.Widthint)
n2.Type = gc.Types[gc.Simtype[gc.TINT]]
gmove(&n2, &n1)
gc.Patch(p1, gc.Pc)
gmove(&n1, res)
regfree(&n1)
break
}
if gc.Isslice(nl.Type) {
var n1 gc.Node
igen(nl, &n1, res)
n1.Type = gc.Types[gc.Simtype[gc.TUINT]]
n1.Xoffset += int64(gc.Array_cap)
gmove(&n1, res)
regfree(&n1)
break
}
gc.Fatal("cgen: OCAP: unknown type %v", gc.Tconv(nl.Type, obj.FmtLong))
case gc.OADDR:
if n.Bounded { // let race detector avoid nil checks
gc.Disable_checknil++
}
agen(nl, res)
if n.Bounded {
gc.Disable_checknil--
}
case gc.OCALLMETH:
gc.Cgen_callmeth(n, 0)
cgen_callret(n, res)
case gc.OCALLINTER:
cgen_callinter(n, res, 0)
cgen_callret(n, res)
case gc.OCALLFUNC:
cgen_call(n, 0)
cgen_callret(n, res)
case gc.OMOD,
gc.ODIV:
if gc.Isfloat[n.Type.Etype] {
a = optoas(int(n.Op), nl.Type)
goto abop
}
if nl.Ullman >= nr.Ullman {
var n1 gc.Node
regalloc(&n1, nl.Type, res)
cgen(nl, &n1)
cgen_div(int(n.Op), &n1, nr, res)
regfree(&n1)
} else {
var n2 gc.Node
if !gc.Smallintconst(nr) {
regalloc(&n2, nr.Type, res)
cgen(nr, &n2)
} else {
n2 = *nr
}
cgen_div(int(n.Op), nl, &n2, res)
if n2.Op != gc.OLITERAL {
regfree(&n2)
}
}
case gc.OLSH,
gc.ORSH,
gc.OLROT:
cgen_shift(int(n.Op), n.Bounded, nl, nr, res)
}
return
/*
* put simplest on right - we'll generate into left
* and then adjust it using the computation of right.
* constants and variables have the same ullman
* count, so look for constants specially.
*
* an integer constant we can use as an immediate
* is simpler than a variable - we can use the immediate
* in the adjustment instruction directly - so it goes
* on the right.
*
* other constants, like big integers or floating point
* constants, require a mov into a register, so those
* might as well go on the left, so we can reuse that
* register for the computation.
*/
sbop: // symmetric binary
if nl.Ullman < nr.Ullman || (nl.Ullman == nr.Ullman && (gc.Smallintconst(nl) || (nr.Op == gc.OLITERAL && !gc.Smallintconst(nr)))) {
r := nl
nl = nr
nr = r
}
abop: // asymmetric binary
var n1 gc.Node
var n2 gc.Node
if nl.Ullman >= nr.Ullman {
regalloc(&n1, nl.Type, res)
cgen(nl, &n1)
/*
* This generates smaller code - it avoids a MOV - but it's
* easily 10% slower due to not being able to
* optimize/manipulate the move.
* To see, run: go test -bench . crypto/md5
* with and without.
*
if(sudoaddable(a, nr, &addr)) {
p1 = gins(a, N, &n1);
p1->from = addr;
gmove(&n1, res);
sudoclean();
regfree(&n1);
goto ret;
}
*
*/
// TODO(minux): enable using constants directly in certain instructions.
//if(smallintconst(nr))
// n2 = *nr;
//else {
regalloc(&n2, nr.Type, nil)
cgen(nr, &n2)
} else //}
{
//if(smallintconst(nr))
// n2 = *nr;
//else {
regalloc(&n2, nr.Type, res)
cgen(nr, &n2)
//}
regalloc(&n1, nl.Type, nil)
cgen(nl, &n1)
}
gins(a, &n2, &n1)
// Normalize result for types smaller than word.
if n.Type.Width < int64(gc.Widthreg) {
switch n.Op {
case gc.OADD,
gc.OSUB,
gc.OMUL,
gc.OLSH:
gins(optoas(gc.OAS, n.Type), &n1, &n1)
}
}
gmove(&n1, res)
regfree(&n1)
if n2.Op != gc.OLITERAL {
regfree(&n2)
}
return
}
/*
* allocate a register (reusing res if possible) and generate
* a = &n
* The caller must call regfree(a).
* The generated code checks that the result is not nil.
*/
func agenr(n *gc.Node, a *gc.Node, res *gc.Node) {
if gc.Debug['g'] != 0 {
gc.Dump("agenr-n", n)
}
nl := n.Left
nr := n.Right
switch n.Op {
case gc.ODOT,
gc.ODOTPTR,
gc.OCALLFUNC,
gc.OCALLMETH,
gc.OCALLINTER:
var n1 gc.Node
igen(n, &n1, res)
regalloc(a, gc.Types[gc.Tptr], &n1)
agen(&n1, a)
regfree(&n1)
case gc.OIND:
cgenr(n.Left, a, res)
gc.Cgen_checknil(a)
case gc.OINDEX:
var p2 *obj.Prog // to be patched to panicindex.
w := uint32(n.Type.Width)
//bounded = debug['B'] || n->bounded;
var n3 gc.Node
var n1 gc.Node
if nr.Addable != 0 {
var tmp gc.Node
if !gc.Isconst(nr, gc.CTINT) {
gc.Tempname(&tmp, gc.Types[gc.TINT64])
}
if !gc.Isconst(nl, gc.CTSTR) {
agenr(nl, &n3, res)
}
if !gc.Isconst(nr, gc.CTINT) {
cgen(nr, &tmp)
regalloc(&n1, tmp.Type, nil)
gmove(&tmp, &n1)
}
} else if nl.Addable != 0 {
if !gc.Isconst(nr, gc.CTINT) {
var tmp gc.Node
gc.Tempname(&tmp, gc.Types[gc.TINT64])
cgen(nr, &tmp)
regalloc(&n1, tmp.Type, nil)
gmove(&tmp, &n1)
}
if !gc.Isconst(nl, gc.CTSTR) {
agenr(nl, &n3, res)
}
} else {
var tmp gc.Node
gc.Tempname(&tmp, gc.Types[gc.TINT64])
cgen(nr, &tmp)
nr = &tmp
if !gc.Isconst(nl, gc.CTSTR) {
agenr(nl, &n3, res)
}
regalloc(&n1, tmp.Type, nil)
gins(optoas(gc.OAS, tmp.Type), &tmp, &n1)
}
// &a is in &n3 (allocated in res)
// i is in &n1 (if not constant)
// w is width
// constant index
if gc.Isconst(nr, gc.CTINT) {
if gc.Isconst(nl, gc.CTSTR) {
gc.Fatal("constant string constant index")
}
v := uint64(gc.Mpgetfix(nr.Val.U.Xval))
if gc.Isslice(nl.Type) || nl.Type.Etype == gc.TSTRING {
if gc.Debug['B'] == 0 && !n.Bounded {
n1 = n3
n1.Op = gc.OINDREG
n1.Type = gc.Types[gc.Tptr]
n1.Xoffset = int64(gc.Array_nel)
var n4 gc.Node
regalloc(&n4, n1.Type, nil)
gmove(&n1, &n4)
ginscon2(optoas(gc.OCMP, gc.Types[gc.TUINT64]), &n4, int64(v))
regfree(&n4)
p1 := gc.Gbranch(optoas(gc.OGT, gc.Types[gc.TUINT64]), nil, +1)
ginscall(gc.Panicindex, 0)
gc.Patch(p1, gc.Pc)
}
n1 = n3
n1.Op = gc.OINDREG
n1.Type = gc.Types[gc.Tptr]
n1.Xoffset = int64(gc.Array_array)
gmove(&n1, &n3)
}
if v*uint64(w) != 0 {
ginscon(optoas(gc.OADD, gc.Types[gc.Tptr]), int64(v*uint64(w)), &n3)
}
*a = n3
break
}
var n2 gc.Node
regalloc(&n2, gc.Types[gc.TINT64], &n1) // i
gmove(&n1, &n2)
regfree(&n1)
var n4 gc.Node
if gc.Debug['B'] == 0 && !n.Bounded {
// check bounds
if gc.Isconst(nl, gc.CTSTR) {
gc.Nodconst(&n4, gc.Types[gc.TUINT64], int64(len(nl.Val.U.Sval)))
} else if gc.Isslice(nl.Type) || nl.Type.Etype == gc.TSTRING {
n1 = n3
n1.Op = gc.OINDREG
n1.Type = gc.Types[gc.Tptr]
n1.Xoffset = int64(gc.Array_nel)
regalloc(&n4, gc.Types[gc.TUINT64], nil)
gmove(&n1, &n4)
} else {
if nl.Type.Bound < (1<<15)-1 {
gc.Nodconst(&n4, gc.Types[gc.TUINT64], nl.Type.Bound)
} else {
regalloc(&n4, gc.Types[gc.TUINT64], nil)
p1 := gins(ppc64.AMOVD, nil, &n4)
p1.From.Type = obj.TYPE_CONST
p1.From.Offset = nl.Type.Bound
}
}
gins(optoas(gc.OCMP, gc.Types[gc.TUINT64]), &n2, &n4)
if n4.Op == gc.OREGISTER {
regfree(&n4)
}
p1 := gc.Gbranch(optoas(gc.OLT, gc.Types[gc.TUINT64]), nil, +1)
if p2 != nil {
gc.Patch(p2, gc.Pc)
}
ginscall(gc.Panicindex, 0)
gc.Patch(p1, gc.Pc)
}
if gc.Isconst(nl, gc.CTSTR) {
regalloc(&n3, gc.Types[gc.Tptr], res)
p1 := gins(ppc64.AMOVD, nil, &n3)
gc.Datastring(nl.Val.U.Sval, &p1.From)
p1.From.Type = obj.TYPE_ADDR
} else if gc.Isslice(nl.Type) || nl.Type.Etype == gc.TSTRING {
n1 = n3
n1.Op = gc.OINDREG
n1.Type = gc.Types[gc.Tptr]
n1.Xoffset = int64(gc.Array_array)
gmove(&n1, &n3)
}
if w == 0 {
} else // nothing to do
if w == 1 {
/* w already scaled */
gins(optoas(gc.OADD, gc.Types[gc.Tptr]), &n2, &n3)
/* else if(w == 2 || w == 4 || w == 8) {
// TODO(minux): scale using shift
} */
} else {
regalloc(&n4, gc.Types[gc.TUINT64], nil)
gc.Nodconst(&n1, gc.Types[gc.TUINT64], int64(w))
gmove(&n1, &n4)
gins(optoas(gc.OMUL, gc.Types[gc.TUINT64]), &n4, &n2)
gins(optoas(gc.OADD, gc.Types[gc.Tptr]), &n2, &n3)
regfree(&n4)
}
*a = n3
regfree(&n2)
default:
regalloc(a, gc.Types[gc.Tptr], res)
agen(n, a)
}
}
/*
* allocate a register (reusing res if possible) and generate
* a = &n
* The caller must call regfree(a).
* The generated code checks that the result is not nil.
*/
func agenr(n *gc.Node, a *gc.Node, res *gc.Node) {
if gc.Debug['g'] != 0 {
gc.Dump("\nagenr-n", n)
}
nl := n.Left
nr := n.Right
switch n.Op {
case gc.ODOT,
gc.ODOTPTR,
gc.OCALLFUNC,
gc.OCALLMETH,
gc.OCALLINTER:
var n1 gc.Node
igen(n, &n1, res)
regalloc(a, gc.Types[gc.Tptr], &n1)
agen(&n1, a)
regfree(&n1)
case gc.OIND:
cgenr(n.Left, a, res)
gc.Cgen_checknil(a)
case gc.OINDEX:
freelen := 0
w := uint64(n.Type.Width)
// Generate the non-addressable child first.
var n3 gc.Node
var nlen gc.Node
var tmp gc.Node
var n1 gc.Node
if nr.Addable != 0 {
goto irad
}
if nl.Addable != 0 {
cgenr(nr, &n1, nil)
if !gc.Isconst(nl, gc.CTSTR) {
if gc.Isfixedarray(nl.Type) {
agenr(nl, &n3, res)
} else {
igen(nl, &nlen, res)
freelen = 1
nlen.Type = gc.Types[gc.Tptr]
nlen.Xoffset += int64(gc.Array_array)
regalloc(&n3, gc.Types[gc.Tptr], res)
gmove(&nlen, &n3)
nlen.Type = gc.Types[gc.Simtype[gc.TUINT]]
nlen.Xoffset += int64(gc.Array_nel) - int64(gc.Array_array)
}
}
goto index
}
gc.Tempname(&tmp, nr.Type)
cgen(nr, &tmp)
nr = &tmp
irad:
if !gc.Isconst(nl, gc.CTSTR) {
if gc.Isfixedarray(nl.Type) {
agenr(nl, &n3, res)
} else {
if nl.Addable == 0 {
// igen will need an addressable node.
var tmp2 gc.Node
gc.Tempname(&tmp2, nl.Type)
cgen(nl, &tmp2)
nl = &tmp2
}
igen(nl, &nlen, res)
freelen = 1
nlen.Type = gc.Types[gc.Tptr]
nlen.Xoffset += int64(gc.Array_array)
regalloc(&n3, gc.Types[gc.Tptr], res)
gmove(&nlen, &n3)
nlen.Type = gc.Types[gc.Simtype[gc.TUINT]]
nlen.Xoffset += int64(gc.Array_nel) - int64(gc.Array_array)
}
}
if !gc.Isconst(nr, gc.CTINT) {
cgenr(nr, &n1, nil)
}
goto index
// &a is in &n3 (allocated in res)
// i is in &n1 (if not constant)
// len(a) is in nlen (if needed)
// w is width
// constant index
index:
if gc.Isconst(nr, gc.CTINT) {
if gc.Isconst(nl, gc.CTSTR) {
gc.Fatal("constant string constant index") // front end should handle
}
v := uint64(gc.Mpgetfix(nr.Val.U.Xval))
if gc.Isslice(nl.Type) || nl.Type.Etype == gc.TSTRING {
if gc.Debug['B'] == 0 && !n.Bounded {
var n2 gc.Node
gc.Nodconst(&n2, gc.Types[gc.Simtype[gc.TUINT]], int64(v))
if gc.Smallintconst(nr) {
gins(optoas(gc.OCMP, gc.Types[gc.Simtype[gc.TUINT]]), &nlen, &n2)
} else {
regalloc(&tmp, gc.Types[gc.Simtype[gc.TUINT]], nil)
gmove(&n2, &tmp)
gins(optoas(gc.OCMP, gc.Types[gc.Simtype[gc.TUINT]]), &nlen, &tmp)
regfree(&tmp)
}
p1 := gc.Gbranch(optoas(gc.OGT, gc.Types[gc.Simtype[gc.TUINT]]), nil, +1)
ginscall(gc.Panicindex, -1)
gc.Patch(p1, gc.Pc)
}
regfree(&nlen)
}
if v*w != 0 {
ginscon(optoas(gc.OADD, gc.Types[gc.Tptr]), int64(v*w), &n3)
}
*a = n3
break
}
// type of the index
t := gc.Types[gc.TUINT64]
if gc.Issigned[n1.Type.Etype] {
t = gc.Types[gc.TINT64]
}
var n2 gc.Node
regalloc(&n2, t, &n1) // i
gmove(&n1, &n2)
regfree(&n1)
if gc.Debug['B'] == 0 && !n.Bounded {
// check bounds
t = gc.Types[gc.Simtype[gc.TUINT]]
if gc.Is64(nr.Type) {
t = gc.Types[gc.TUINT64]
}
if gc.Isconst(nl, gc.CTSTR) {
gc.Nodconst(&nlen, t, int64(len(nl.Val.U.Sval)))
} else if gc.Isslice(nl.Type) || nl.Type.Etype == gc.TSTRING {
if gc.Is64(nr.Type) {
var n5 gc.Node
regalloc(&n5, t, nil)
gmove(&nlen, &n5)
regfree(&nlen)
nlen = n5
}
} else {
gc.Nodconst(&nlen, t, nl.Type.Bound)
if !gc.Smallintconst(&nlen) {
var n5 gc.Node
regalloc(&n5, t, nil)
gmove(&nlen, &n5)
nlen = n5
freelen = 1
}
}
gins(optoas(gc.OCMP, t), &n2, &nlen)
p1 := gc.Gbranch(optoas(gc.OLT, t), nil, +1)
ginscall(gc.Panicindex, -1)
gc.Patch(p1, gc.Pc)
}
if gc.Isconst(nl, gc.CTSTR) {
regalloc(&n3, gc.Types[gc.Tptr], res)
p1 := gins(x86.ALEAQ, nil, &n3)
gc.Datastring(nl.Val.U.Sval, &p1.From)
gins(x86.AADDQ, &n2, &n3)
goto indexdone
}
if w == 0 {
} else // nothing to do
if w == 1 || w == 2 || w == 4 || w == 8 {
p1 := gins(x86.ALEAQ, &n2, &n3)
p1.From.Type = obj.TYPE_MEM
p1.From.Scale = int16(w)
p1.From.Index = p1.From.Reg
p1.From.Reg = p1.To.Reg
} else {
ginscon(optoas(gc.OMUL, t), int64(w), &n2)
gins(optoas(gc.OADD, gc.Types[gc.Tptr]), &n2, &n3)
}
indexdone:
*a = n3
regfree(&n2)
if freelen != 0 {
regfree(&nlen)
}
default:
regalloc(a, gc.Types[gc.Tptr], res)
agen(n, a)
}
}
/*
* generate:
* newreg = &n;
*
* caller must regfree(a).
* The generated code checks that the result is not nil.
*/
func agenr(n *gc.Node, a *gc.Node, res *gc.Node) {
if gc.Debug['g'] != 0 {
gc.Dump("agenr-n", n)
}
nl := n.Left
nr := n.Right
switch n.Op {
case gc.ODOT,
gc.ODOTPTR,
gc.OCALLFUNC,
gc.OCALLMETH,
gc.OCALLINTER:
var n1 gc.Node
igen(n, &n1, res)
regalloc(a, gc.Types[gc.Tptr], &n1)
agen(&n1, a)
regfree(&n1)
case gc.OIND:
cgenr(n.Left, a, res)
gc.Cgen_checknil(a)
case gc.OINDEX:
var p2 *obj.Prog // to be patched to panicindex.
w := uint32(n.Type.Width)
bounded := gc.Debug['B'] != 0 || n.Bounded
var n1 gc.Node
var n3 gc.Node
if nr.Addable != 0 {
var tmp gc.Node
if !gc.Isconst(nr, gc.CTINT) {
gc.Tempname(&tmp, gc.Types[gc.TINT32])
}
if !gc.Isconst(nl, gc.CTSTR) {
agenr(nl, &n3, res)
}
if !gc.Isconst(nr, gc.CTINT) {
p2 = cgenindex(nr, &tmp, bounded)
regalloc(&n1, tmp.Type, nil)
gmove(&tmp, &n1)
}
} else if nl.Addable != 0 {
if !gc.Isconst(nr, gc.CTINT) {
var tmp gc.Node
gc.Tempname(&tmp, gc.Types[gc.TINT32])
p2 = cgenindex(nr, &tmp, bounded)
regalloc(&n1, tmp.Type, nil)
gmove(&tmp, &n1)
}
if !gc.Isconst(nl, gc.CTSTR) {
agenr(nl, &n3, res)
}
} else {
var tmp gc.Node
gc.Tempname(&tmp, gc.Types[gc.TINT32])
p2 = cgenindex(nr, &tmp, bounded)
nr = &tmp
if !gc.Isconst(nl, gc.CTSTR) {
agenr(nl, &n3, res)
}
regalloc(&n1, tmp.Type, nil)
gins(optoas(gc.OAS, tmp.Type), &tmp, &n1)
}
// &a is in &n3 (allocated in res)
// i is in &n1 (if not constant)
// w is width
// constant index
if gc.Isconst(nr, gc.CTINT) {
if gc.Isconst(nl, gc.CTSTR) {
gc.Fatal("constant string constant index")
}
v := uint64(gc.Mpgetfix(nr.Val.U.Xval))
var n2 gc.Node
if gc.Isslice(nl.Type) || nl.Type.Etype == gc.TSTRING {
if gc.Debug['B'] == 0 && !n.Bounded {
n1 = n3
n1.Op = gc.OINDREG
n1.Type = gc.Types[gc.Tptr]
n1.Xoffset = int64(gc.Array_nel)
var n4 gc.Node
regalloc(&n4, n1.Type, nil)
gmove(&n1, &n4)
gc.Nodconst(&n2, gc.Types[gc.TUINT32], int64(v))
gcmp(optoas(gc.OCMP, gc.Types[gc.TUINT32]), &n4, &n2)
regfree(&n4)
p1 := gc.Gbranch(optoas(gc.OGT, gc.Types[gc.TUINT32]), nil, +1)
ginscall(gc.Panicindex, 0)
gc.Patch(p1, gc.Pc)
}
n1 = n3
n1.Op = gc.OINDREG
n1.Type = gc.Types[gc.Tptr]
n1.Xoffset = int64(gc.Array_array)
gmove(&n1, &n3)
}
gc.Nodconst(&n2, gc.Types[gc.Tptr], int64(v*uint64(w)))
gins(optoas(gc.OADD, gc.Types[gc.Tptr]), &n2, &n3)
*a = n3
break
}
var n2 gc.Node
regalloc(&n2, gc.Types[gc.TINT32], &n1) // i
gmove(&n1, &n2)
regfree(&n1)
var n4 gc.Node
if gc.Debug['B'] == 0 && !n.Bounded {
// check bounds
if gc.Isconst(nl, gc.CTSTR) {
gc.Nodconst(&n4, gc.Types[gc.TUINT32], int64(len(nl.Val.U.Sval)))
} else if gc.Isslice(nl.Type) || nl.Type.Etype == gc.TSTRING {
n1 = n3
n1.Op = gc.OINDREG
n1.Type = gc.Types[gc.Tptr]
n1.Xoffset = int64(gc.Array_nel)
regalloc(&n4, gc.Types[gc.TUINT32], nil)
gmove(&n1, &n4)
} else {
gc.Nodconst(&n4, gc.Types[gc.TUINT32], nl.Type.Bound)
}
gcmp(optoas(gc.OCMP, gc.Types[gc.TUINT32]), &n2, &n4)
if n4.Op == gc.OREGISTER {
regfree(&n4)
}
p1 := gc.Gbranch(optoas(gc.OLT, gc.Types[gc.TUINT32]), nil, +1)
if p2 != nil {
gc.Patch(p2, gc.Pc)
}
ginscall(gc.Panicindex, 0)
gc.Patch(p1, gc.Pc)
}
if gc.Isconst(nl, gc.CTSTR) {
regalloc(&n3, gc.Types[gc.Tptr], res)
p1 := gins(arm.AMOVW, nil, &n3)
gc.Datastring(nl.Val.U.Sval, &p1.From)
p1.From.Type = obj.TYPE_ADDR
} else if gc.Isslice(nl.Type) || nl.Type.Etype == gc.TSTRING {
n1 = n3
n1.Op = gc.OINDREG
n1.Type = gc.Types[gc.Tptr]
n1.Xoffset = int64(gc.Array_array)
gmove(&n1, &n3)
}
if w == 0 {
} else // nothing to do
if w == 1 || w == 2 || w == 4 || w == 8 {
n4 = gc.Node{}
n4.Op = gc.OADDR
n4.Left = &n2
cgen(&n4, &n3)
if w == 1 {
gins(arm.AADD, &n2, &n3)
} else if w == 2 {
gshift(arm.AADD, &n2, arm.SHIFT_LL, 1, &n3)
} else if w == 4 {
gshift(arm.AADD, &n2, arm.SHIFT_LL, 2, &n3)
} else if w == 8 {
gshift(arm.AADD, &n2, arm.SHIFT_LL, 3, &n3)
}
} else {
regalloc(&n4, gc.Types[gc.TUINT32], nil)
gc.Nodconst(&n1, gc.Types[gc.TUINT32], int64(w))
gmove(&n1, &n4)
gins(optoas(gc.OMUL, gc.Types[gc.TUINT32]), &n4, &n2)
gins(optoas(gc.OADD, gc.Types[gc.Tptr]), &n2, &n3)
regfree(&n4)
}
*a = n3
regfree(&n2)
default:
regalloc(a, gc.Types[gc.Tptr], res)
agen(n, a)
}
}
/*
* generate:
* res = n;
* simplifies and calls gmove.
*/
func cgen(n *gc.Node, res *gc.Node) {
if gc.Debug['g'] != 0 {
gc.Dump("\ncgen-n", n)
gc.Dump("cgen-res", res)
}
if n == nil || n.Type == nil {
return
}
if res == nil || res.Type == nil {
gc.Fatal("cgen: res nil")
}
switch n.Op {
case gc.OSLICE,
gc.OSLICEARR,
gc.OSLICESTR,
gc.OSLICE3,
gc.OSLICE3ARR:
if res.Op != gc.ONAME || res.Addable == 0 {
var n1 gc.Node
gc.Tempname(&n1, n.Type)
gc.Cgen_slice(n, &n1)
cgen(&n1, res)
} else {
gc.Cgen_slice(n, res)
}
return
case gc.OEFACE:
if res.Op != gc.ONAME || res.Addable == 0 {
var n1 gc.Node
gc.Tempname(&n1, n.Type)
gc.Cgen_eface(n, &n1)
cgen(&n1, res)
} else {
gc.Cgen_eface(n, res)
}
return
}
for n.Op == gc.OCONVNOP {
n = n.Left
}
if n.Ullman >= gc.UINF {
if n.Op == gc.OINDREG {
gc.Fatal("cgen: this is going to misscompile")
}
if res.Ullman >= gc.UINF {
var n1 gc.Node
gc.Tempname(&n1, n.Type)
cgen(n, &n1)
cgen(&n1, res)
return
}
}
if gc.Isfat(n.Type) {
if n.Type.Width < 0 {
gc.Fatal("forgot to compute width for %v", gc.Tconv(n.Type, 0))
}
sgen(n, res, n.Type.Width)
return
}
// update addressability for string, slice
// can't do in walk because n->left->addable
// changes if n->left is an escaping local variable.
switch n.Op {
case gc.OSPTR,
gc.OLEN:
if gc.Isslice(n.Left.Type) || gc.Istype(n.Left.Type, gc.TSTRING) {
n.Addable = n.Left.Addable
}
case gc.OCAP:
if gc.Isslice(n.Left.Type) {
n.Addable = n.Left.Addable
}
case gc.OITAB:
n.Addable = n.Left.Addable
}
// if both are addressable, move
if n.Addable != 0 && res.Addable != 0 {
if gc.Is64(n.Type) || gc.Is64(res.Type) || n.Op == gc.OREGISTER || res.Op == gc.OREGISTER || gc.Iscomplex[n.Type.Etype] || gc.Iscomplex[res.Type.Etype] {
gmove(n, res)
} else {
var n1 gc.Node
regalloc(&n1, n.Type, nil)
gmove(n, &n1)
cgen(&n1, res)
regfree(&n1)
}
return
}
// if both are not addressable, use a temporary.
if n.Addable == 0 && res.Addable == 0 {
// could use regalloc here sometimes,
// but have to check for ullman >= UINF.
var n1 gc.Node
gc.Tempname(&n1, n.Type)
cgen(n, &n1)
cgen(&n1, res)
return
}
// if result is not addressable directly but n is,
// compute its address and then store via the address.
if res.Addable == 0 {
var n1 gc.Node
igen(res, &n1, nil)
cgen(n, &n1)
regfree(&n1)
return
}
if gc.Complexop(n, res) {
gc.Complexgen(n, res)
return
}
// if n is sudoaddable generate addr and move
if !gc.Is64(n.Type) && !gc.Is64(res.Type) && !gc.Iscomplex[n.Type.Etype] && !gc.Iscomplex[res.Type.Etype] {
a := optoas(gc.OAS, n.Type)
var w int
var addr obj.Addr
if sudoaddable(a, n, &addr, &w) {
if res.Op != gc.OREGISTER {
var n2 gc.Node
regalloc(&n2, res.Type, nil)
p1 := gins(a, nil, &n2)
p1.From = addr
if gc.Debug['g'] != 0 {
fmt.Printf("%v [ignore previous line]\n", p1)
}
gmove(&n2, res)
regfree(&n2)
} else {
p1 := gins(a, nil, res)
p1.From = addr
if gc.Debug['g'] != 0 {
fmt.Printf("%v [ignore previous line]\n", p1)
}
}
sudoclean()
return
}
}
// otherwise, the result is addressable but n is not.
// let's do some computation.
nl := n.Left
nr := n.Right
if nl != nil && nl.Ullman >= gc.UINF {
if nr != nil && nr.Ullman >= gc.UINF {
var n1 gc.Node
gc.Tempname(&n1, nl.Type)
cgen(nl, &n1)
n2 := *n
n2.Left = &n1
cgen(&n2, res)
return
}
}
// 64-bit ops are hard on 32-bit machine.
if gc.Is64(n.Type) || gc.Is64(res.Type) || n.Left != nil && gc.Is64(n.Left.Type) {
switch n.Op {
// math goes to cgen64.
case gc.OMINUS,
gc.OCOM,
gc.OADD,
gc.OSUB,
gc.OMUL,
gc.OLROT,
gc.OLSH,
gc.ORSH,
gc.OAND,
gc.OOR,
gc.OXOR:
cgen64(n, res)
return
}
}
var a int
var f0 gc.Node
var n1 gc.Node
var n2 gc.Node
if nl != nil && gc.Isfloat[n.Type.Etype] && gc.Isfloat[nl.Type.Etype] {
// floating-point.
regalloc(&f0, nl.Type, res)
if nr != nil {
goto flt2
}
if n.Op == gc.OMINUS {
nr = gc.Nodintconst(-1)
gc.Convlit(&nr, n.Type)
n.Op = gc.OMUL
goto flt2
}
// unary
cgen(nl, &f0)
if n.Op != gc.OCONV && n.Op != gc.OPLUS {
gins(optoas(int(n.Op), n.Type), &f0, &f0)
}
gmove(&f0, res)
regfree(&f0)
return
}
switch n.Op {
default:
gc.Dump("cgen", n)
gc.Fatal("cgen: unknown op %v", gc.Nconv(n, obj.FmtShort|obj.FmtSign))
case gc.OREAL,
gc.OIMAG,
gc.OCOMPLEX:
gc.Fatal("unexpected complex")
// these call bgen to get a bool value
case gc.OOROR,
gc.OANDAND,
gc.OEQ,
gc.ONE,
gc.OLT,
gc.OLE,
gc.OGE,
gc.OGT,
gc.ONOT:
p1 := gc.Gbranch(arm.AB, nil, 0)
p2 := gc.Pc
gmove(gc.Nodbool(true), res)
p3 := gc.Gbranch(arm.AB, nil, 0)
gc.Patch(p1, gc.Pc)
bgen(n, true, 0, p2)
gmove(gc.Nodbool(false), res)
gc.Patch(p3, gc.Pc)
return
case gc.OPLUS:
cgen(nl, res)
return
// unary
case gc.OCOM:
a := optoas(gc.OXOR, nl.Type)
regalloc(&n1, nl.Type, nil)
cgen(nl, &n1)
gc.Nodconst(&n2, nl.Type, -1)
gins(a, &n2, &n1)
goto norm
case gc.OMINUS:
regalloc(&n1, nl.Type, nil)
cgen(nl, &n1)
gc.Nodconst(&n2, nl.Type, 0)
gins(optoas(gc.OMINUS, nl.Type), &n2, &n1)
goto norm
// symmetric binary
case gc.OAND,
gc.OOR,
gc.OXOR,
gc.OADD,
gc.OMUL:
a = optoas(int(n.Op), nl.Type)
// symmetric binary
if nl.Ullman < nr.Ullman {
r := nl
nl = nr
nr = r
}
goto abop
// asymmetric binary
case gc.OSUB:
a = optoas(int(n.Op), nl.Type)
goto abop
case gc.OHMUL:
cgen_hmul(nl, nr, res)
case gc.OLROT,
gc.OLSH,
gc.ORSH:
cgen_shift(int(n.Op), n.Bounded, nl, nr, res)
case gc.OCONV:
if gc.Eqtype(n.Type, nl.Type) || gc.Noconv(n.Type, nl.Type) {
cgen(nl, res)
break
}
var n1 gc.Node
if nl.Addable != 0 && !gc.Is64(nl.Type) {
regalloc(&n1, nl.Type, res)
gmove(nl, &n1)
} else {
if n.Type.Width > int64(gc.Widthptr) || gc.Is64(nl.Type) || gc.Isfloat[nl.Type.Etype] {
gc.Tempname(&n1, nl.Type)
} else {
regalloc(&n1, nl.Type, res)
}
cgen(nl, &n1)
}
var n2 gc.Node
if n.Type.Width > int64(gc.Widthptr) || gc.Is64(n.Type) || gc.Isfloat[n.Type.Etype] {
gc.Tempname(&n2, n.Type)
} else {
regalloc(&n2, n.Type, nil)
}
gmove(&n1, &n2)
gmove(&n2, res)
if n1.Op == gc.OREGISTER {
regfree(&n1)
}
if n2.Op == gc.OREGISTER {
regfree(&n2)
}
case gc.ODOT,
gc.ODOTPTR,
gc.OINDEX,
gc.OIND,
gc.ONAME: // PHEAP or PPARAMREF var
var n1 gc.Node
igen(n, &n1, res)
gmove(&n1, res)
regfree(&n1)
// interface table is first word of interface value
case gc.OITAB:
var n1 gc.Node
igen(nl, &n1, res)
n1.Type = n.Type
gmove(&n1, res)
regfree(&n1)
// pointer is the first word of string or slice.
case gc.OSPTR:
if gc.Isconst(nl, gc.CTSTR) {
var n1 gc.Node
regalloc(&n1, gc.Types[gc.Tptr], res)
p1 := gins(arm.AMOVW, nil, &n1)
gc.Datastring(nl.Val.U.Sval, &p1.From)
gmove(&n1, res)
regfree(&n1)
break
}
var n1 gc.Node
igen(nl, &n1, res)
n1.Type = n.Type
gmove(&n1, res)
regfree(&n1)
case gc.OLEN:
if gc.Istype(nl.Type, gc.TMAP) || gc.Istype(nl.Type, gc.TCHAN) {
// map has len in the first 32-bit word.
// a zero pointer means zero length
var n1 gc.Node
regalloc(&n1, gc.Types[gc.Tptr], res)
cgen(nl, &n1)
var n2 gc.Node
gc.Nodconst(&n2, gc.Types[gc.Tptr], 0)
gcmp(optoas(gc.OCMP, gc.Types[gc.Tptr]), &n1, &n2)
p1 := gc.Gbranch(optoas(gc.OEQ, gc.Types[gc.Tptr]), nil, -1)
n2 = n1
n2.Op = gc.OINDREG
n2.Type = gc.Types[gc.TINT32]
gmove(&n2, &n1)
gc.Patch(p1, gc.Pc)
gmove(&n1, res)
regfree(&n1)
break
}
if gc.Istype(nl.Type, gc.TSTRING) || gc.Isslice(nl.Type) {
// both slice and string have len one pointer into the struct.
var n1 gc.Node
igen(nl, &n1, res)
n1.Type = gc.Types[gc.TUINT32]
n1.Xoffset += int64(gc.Array_nel)
gmove(&n1, res)
regfree(&n1)
break
}
gc.Fatal("cgen: OLEN: unknown type %v", gc.Tconv(nl.Type, obj.FmtLong))
case gc.OCAP:
if gc.Istype(nl.Type, gc.TCHAN) {
// chan has cap in the second 32-bit word.
// a zero pointer means zero length
var n1 gc.Node
regalloc(&n1, gc.Types[gc.Tptr], res)
cgen(nl, &n1)
var n2 gc.Node
gc.Nodconst(&n2, gc.Types[gc.Tptr], 0)
gcmp(optoas(gc.OCMP, gc.Types[gc.Tptr]), &n1, &n2)
p1 := gc.Gbranch(optoas(gc.OEQ, gc.Types[gc.Tptr]), nil, -1)
n2 = n1
n2.Op = gc.OINDREG
n2.Xoffset = 4
n2.Type = gc.Types[gc.TINT32]
gmove(&n2, &n1)
gc.Patch(p1, gc.Pc)
gmove(&n1, res)
regfree(&n1)
break
}
if gc.Isslice(nl.Type) {
var n1 gc.Node
igen(nl, &n1, res)
n1.Type = gc.Types[gc.TUINT32]
n1.Xoffset += int64(gc.Array_cap)
gmove(&n1, res)
regfree(&n1)
break
}
gc.Fatal("cgen: OCAP: unknown type %v", gc.Tconv(nl.Type, obj.FmtLong))
case gc.OADDR:
agen(nl, res)
// Release res so that it is available for cgen_call.
// Pick it up again after the call.
case gc.OCALLMETH,
gc.OCALLFUNC:
rg := -1
if n.Ullman >= gc.UINF {
if res != nil && (res.Op == gc.OREGISTER || res.Op == gc.OINDREG) {
rg = int(res.Val.U.Reg)
reg[rg]--
}
}
if n.Op == gc.OCALLMETH {
gc.Cgen_callmeth(n, 0)
} else {
cgen_call(n, 0)
}
if rg >= 0 {
reg[rg]++
}
cgen_callret(n, res)
case gc.OCALLINTER:
cgen_callinter(n, res, 0)
cgen_callret(n, res)
case gc.OMOD,
gc.ODIV:
a = optoas(int(n.Op), nl.Type)
goto abop
}
return
// TODO(kaib): use fewer registers here.
abop: // asymmetric binary
if nl.Ullman >= nr.Ullman {
regalloc(&n1, nl.Type, res)
cgen(nl, &n1)
switch n.Op {
case gc.OADD,
gc.OSUB,
gc.OAND,
gc.OOR,
gc.OXOR:
if gc.Smallintconst(nr) {
n2 = *nr
break
}
fallthrough
default:
regalloc(&n2, nr.Type, nil)
cgen(nr, &n2)
}
} else {
switch n.Op {
case gc.OADD,
gc.OSUB,
gc.OAND,
gc.OOR,
gc.OXOR:
if gc.Smallintconst(nr) {
n2 = *nr
break
}
fallthrough
default:
regalloc(&n2, nr.Type, res)
cgen(nr, &n2)
}
regalloc(&n1, nl.Type, nil)
cgen(nl, &n1)
}
gins(a, &n2, &n1)
// Normalize result for types smaller than word.
norm:
if n.Type.Width < int64(gc.Widthptr) {
switch n.Op {
case gc.OADD,
gc.OSUB,
gc.OMUL,
gc.OCOM,
gc.OMINUS:
gins(optoas(gc.OAS, n.Type), &n1, &n1)
}
}
gmove(&n1, res)
regfree(&n1)
if n2.Op != gc.OLITERAL {
regfree(&n2)
}
return
flt2: // binary
var f1 gc.Node
if nl.Ullman >= nr.Ullman {
cgen(nl, &f0)
regalloc(&f1, n.Type, nil)
gmove(&f0, &f1)
cgen(nr, &f0)
gins(optoas(int(n.Op), n.Type), &f0, &f1)
} else {
cgen(nr, &f0)
regalloc(&f1, n.Type, nil)
cgen(nl, &f1)
gins(optoas(int(n.Op), n.Type), &f0, &f1)
}
gmove(&f1, res)
regfree(&f0)
regfree(&f1)
return
}
/*
* address gen
* res = &n;
* The generated code checks that the result is not nil.
*/
func agen(n *gc.Node, res *gc.Node) {
if gc.Debug['g'] != 0 {
gc.Dump("\nagen-res", res)
gc.Dump("agen-r", n)
}
if n == nil || n.Type == nil || res == nil || res.Type == nil {
gc.Fatal("agen")
}
for n.Op == gc.OCONVNOP {
n = n.Left
}
if gc.Isconst(n, gc.CTNIL) && n.Type.Width > int64(gc.Widthptr) {
// Use of a nil interface or nil slice.
// Create a temporary we can take the address of and read.
// The generated code is just going to panic, so it need not
// be terribly efficient. See issue 3670.
var n1 gc.Node
gc.Tempname(&n1, n.Type)
gc.Gvardef(&n1)
clearfat(&n1)
var n2 gc.Node
regalloc(&n2, gc.Types[gc.Tptr], res)
gins(x86.ALEAL, &n1, &n2)
gmove(&n2, res)
regfree(&n2)
return
}
// addressable var is easy
if n.Addable != 0 {
if n.Op == gc.OREGISTER {
gc.Fatal("agen OREGISTER")
}
var n1 gc.Node
regalloc(&n1, gc.Types[gc.Tptr], res)
gins(x86.ALEAL, n, &n1)
gmove(&n1, res)
regfree(&n1)
return
}
// let's compute
nl := n.Left
nr := n.Right
switch n.Op {
default:
gc.Fatal("agen %v", gc.Oconv(int(n.Op), 0))
case gc.OCALLMETH:
gc.Cgen_callmeth(n, 0)
cgen_aret(n, res)
case gc.OCALLINTER:
cgen_callinter(n, res, 0)
cgen_aret(n, res)
case gc.OCALLFUNC:
cgen_call(n, 0)
cgen_aret(n, res)
case gc.OSLICE,
gc.OSLICEARR,
gc.OSLICESTR,
gc.OSLICE3,
gc.OSLICE3ARR:
var n1 gc.Node
gc.Tempname(&n1, n.Type)
gc.Cgen_slice(n, &n1)
agen(&n1, res)
case gc.OEFACE:
var n1 gc.Node
gc.Tempname(&n1, n.Type)
gc.Cgen_eface(n, &n1)
agen(&n1, res)
case gc.OINDEX:
var p2 *obj.Prog // to be patched to panicindex.
w := uint32(n.Type.Width)
bounded := gc.Debug['B'] != 0 || n.Bounded
var n3 gc.Node
var tmp gc.Node
var n1 gc.Node
if nr.Addable != 0 {
// Generate &nl first, and move nr into register.
if !gc.Isconst(nl, gc.CTSTR) {
igen(nl, &n3, res)
}
if !gc.Isconst(nr, gc.CTINT) {
p2 = igenindex(nr, &tmp, bool2int(bounded))
regalloc(&n1, tmp.Type, nil)
gmove(&tmp, &n1)
}
} else if nl.Addable != 0 {
// Generate nr first, and move &nl into register.
if !gc.Isconst(nr, gc.CTINT) {
p2 = igenindex(nr, &tmp, bool2int(bounded))
regalloc(&n1, tmp.Type, nil)
gmove(&tmp, &n1)
}
if !gc.Isconst(nl, gc.CTSTR) {
igen(nl, &n3, res)
}
} else {
p2 = igenindex(nr, &tmp, bool2int(bounded))
nr = &tmp
if !gc.Isconst(nl, gc.CTSTR) {
igen(nl, &n3, res)
}
regalloc(&n1, tmp.Type, nil)
gins(optoas(gc.OAS, tmp.Type), &tmp, &n1)
}
// For fixed array we really want the pointer in n3.
var n2 gc.Node
if gc.Isfixedarray(nl.Type) {
regalloc(&n2, gc.Types[gc.Tptr], &n3)
agen(&n3, &n2)
regfree(&n3)
n3 = n2
}
// &a[0] is in n3 (allocated in res)
// i is in n1 (if not constant)
// len(a) is in nlen (if needed)
// w is width
// constant index
if gc.Isconst(nr, gc.CTINT) {
if gc.Isconst(nl, gc.CTSTR) {
gc.Fatal("constant string constant index") // front end should handle
}
v := uint64(gc.Mpgetfix(nr.Val.U.Xval))
if gc.Isslice(nl.Type) || nl.Type.Etype == gc.TSTRING {
if gc.Debug['B'] == 0 && !n.Bounded {
nlen := n3
nlen.Type = gc.Types[gc.TUINT32]
nlen.Xoffset += int64(gc.Array_nel)
gc.Nodconst(&n2, gc.Types[gc.TUINT32], int64(v))
gins(optoas(gc.OCMP, gc.Types[gc.TUINT32]), &nlen, &n2)
p1 := gc.Gbranch(optoas(gc.OGT, gc.Types[gc.TUINT32]), nil, +1)
ginscall(gc.Panicindex, -1)
gc.Patch(p1, gc.Pc)
}
}
// Load base pointer in n2 = n3.
regalloc(&n2, gc.Types[gc.Tptr], &n3)
n3.Type = gc.Types[gc.Tptr]
n3.Xoffset += int64(gc.Array_array)
gmove(&n3, &n2)
regfree(&n3)
if v*uint64(w) != 0 {
gc.Nodconst(&n1, gc.Types[gc.Tptr], int64(v*uint64(w)))
gins(optoas(gc.OADD, gc.Types[gc.Tptr]), &n1, &n2)
}
gmove(&n2, res)
regfree(&n2)
break
}
// i is in register n1, extend to 32 bits.
t := gc.Types[gc.TUINT32]
if gc.Issigned[n1.Type.Etype] {
t = gc.Types[gc.TINT32]
}
regalloc(&n2, t, &n1) // i
gmove(&n1, &n2)
regfree(&n1)
if gc.Debug['B'] == 0 && !n.Bounded {
// check bounds
t := gc.Types[gc.TUINT32]
var nlen gc.Node
if gc.Isconst(nl, gc.CTSTR) {
gc.Nodconst(&nlen, t, int64(len(nl.Val.U.Sval)))
} else if gc.Isslice(nl.Type) || nl.Type.Etype == gc.TSTRING {
nlen = n3
nlen.Type = t
nlen.Xoffset += int64(gc.Array_nel)
} else {
gc.Nodconst(&nlen, t, nl.Type.Bound)
}
gins(optoas(gc.OCMP, t), &n2, &nlen)
p1 := gc.Gbranch(optoas(gc.OLT, t), nil, +1)
if p2 != nil {
gc.Patch(p2, gc.Pc)
}
ginscall(gc.Panicindex, -1)
gc.Patch(p1, gc.Pc)
}
if gc.Isconst(nl, gc.CTSTR) {
regalloc(&n3, gc.Types[gc.Tptr], res)
p1 := gins(x86.ALEAL, nil, &n3)
gc.Datastring(nl.Val.U.Sval, &p1.From)
p1.From.Scale = 1
p1.From.Index = n2.Val.U.Reg
goto indexdone
}
// Load base pointer in n3.
regalloc(&tmp, gc.Types[gc.Tptr], &n3)
if gc.Isslice(nl.Type) || nl.Type.Etype == gc.TSTRING {
n3.Type = gc.Types[gc.Tptr]
n3.Xoffset += int64(gc.Array_array)
gmove(&n3, &tmp)
}
regfree(&n3)
n3 = tmp
if w == 0 {
} else // nothing to do
if w == 1 || w == 2 || w == 4 || w == 8 {
// LEAL (n3)(n2*w), n3
p1 := gins(x86.ALEAL, &n2, &n3)
p1.From.Scale = int16(w)
p1.From.Type = obj.TYPE_MEM
p1.From.Index = p1.From.Reg
p1.From.Reg = p1.To.Reg
} else {
gc.Nodconst(&tmp, gc.Types[gc.TUINT32], int64(w))
gins(optoas(gc.OMUL, gc.Types[gc.TUINT32]), &tmp, &n2)
gins(optoas(gc.OADD, gc.Types[gc.Tptr]), &n2, &n3)
}
indexdone:
gmove(&n3, res)
regfree(&n2)
regfree(&n3)
// should only get here with names in this func.
case gc.ONAME:
if n.Funcdepth > 0 && n.Funcdepth != gc.Funcdepth {
gc.Dump("bad agen", n)
gc.Fatal("agen: bad ONAME funcdepth %d != %d", n.Funcdepth, gc.Funcdepth)
}
// should only get here for heap vars or paramref
if n.Class&gc.PHEAP == 0 && n.Class != gc.PPARAMREF {
gc.Dump("bad agen", n)
gc.Fatal("agen: bad ONAME class %#x", n.Class)
}
cgen(n.Heapaddr, res)
if n.Xoffset != 0 {
var n1 gc.Node
gc.Nodconst(&n1, gc.Types[gc.Tptr], n.Xoffset)
gins(optoas(gc.OADD, gc.Types[gc.Tptr]), &n1, res)
}
case gc.OIND:
cgen(nl, res)
gc.Cgen_checknil(res)
case gc.ODOT:
agen(nl, res)
if n.Xoffset != 0 {
var n1 gc.Node
gc.Nodconst(&n1, gc.Types[gc.Tptr], n.Xoffset)
gins(optoas(gc.OADD, gc.Types[gc.Tptr]), &n1, res)
}
case gc.ODOTPTR:
t := nl.Type
if !gc.Isptr[t.Etype] {
gc.Fatal("agen: not ptr %v", gc.Nconv(n, 0))
}
cgen(nl, res)
gc.Cgen_checknil(res)
if n.Xoffset != 0 {
var n1 gc.Node
gc.Nodconst(&n1, gc.Types[gc.Tptr], n.Xoffset)
gins(optoas(gc.OADD, gc.Types[gc.Tptr]), &n1, res)
}
}
}
/*
* generate:
* res = n;
* simplifies and calls gmove.
*
* TODO:
* sudoaddable
*/
func cgen(n *gc.Node, res *gc.Node) {
if gc.Debug['g'] != 0 {
gc.Dump("\ncgen-n", n)
gc.Dump("cgen-res", res)
}
if n == nil || n.Type == nil {
gc.Fatal("cgen: n nil")
}
if res == nil || res.Type == nil {
gc.Fatal("cgen: res nil")
}
switch n.Op {
case gc.OSLICE,
gc.OSLICEARR,
gc.OSLICESTR,
gc.OSLICE3,
gc.OSLICE3ARR:
if res.Op != gc.ONAME || res.Addable == 0 {
var n1 gc.Node
gc.Tempname(&n1, n.Type)
gc.Cgen_slice(n, &n1)
cgen(&n1, res)
} else {
gc.Cgen_slice(n, res)
}
return
case gc.OEFACE:
if res.Op != gc.ONAME || res.Addable == 0 {
var n1 gc.Node
gc.Tempname(&n1, n.Type)
gc.Cgen_eface(n, &n1)
cgen(&n1, res)
} else {
gc.Cgen_eface(n, res)
}
return
}
for n.Op == gc.OCONVNOP {
n = n.Left
}
// function calls on both sides? introduce temporary
if n.Ullman >= gc.UINF && res.Ullman >= gc.UINF {
var n1 gc.Node
gc.Tempname(&n1, n.Type)
cgen(n, &n1)
cgen(&n1, res)
return
}
// structs etc get handled specially
if gc.Isfat(n.Type) {
if n.Type.Width < 0 {
gc.Fatal("forgot to compute width for %v", gc.Tconv(n.Type, 0))
}
sgen(n, res, n.Type.Width)
return
}
// update addressability for string, slice
// can't do in walk because n->left->addable
// changes if n->left is an escaping local variable.
switch n.Op {
case gc.OSPTR,
gc.OLEN:
if gc.Isslice(n.Left.Type) || gc.Istype(n.Left.Type, gc.TSTRING) {
n.Addable = n.Left.Addable
}
case gc.OCAP:
if gc.Isslice(n.Left.Type) {
n.Addable = n.Left.Addable
}
case gc.OITAB:
n.Addable = n.Left.Addable
}
// if both are addressable, move
if n.Addable != 0 && res.Addable != 0 {
gmove(n, res)
return
}
// if both are not addressable, use a temporary.
if n.Addable == 0 && res.Addable == 0 {
// could use regalloc here sometimes,
// but have to check for ullman >= UINF.
var n1 gc.Node
gc.Tempname(&n1, n.Type)
cgen(n, &n1)
cgen(&n1, res)
return
}
// if result is not addressable directly but n is,
// compute its address and then store via the address.
if res.Addable == 0 {
var n1 gc.Node
igen(res, &n1, nil)
cgen(n, &n1)
regfree(&n1)
return
}
// complex types
if gc.Complexop(n, res) {
gc.Complexgen(n, res)
return
}
// otherwise, the result is addressable but n is not.
// let's do some computation.
// use ullman to pick operand to eval first.
nl := n.Left
nr := n.Right
if nl != nil && nl.Ullman >= gc.UINF {
if nr != nil && nr.Ullman >= gc.UINF {
// both are hard
var n1 gc.Node
gc.Tempname(&n1, nl.Type)
cgen(nl, &n1)
n2 := *n
n2.Left = &n1
cgen(&n2, res)
return
}
}
// 64-bit ops are hard on 32-bit machine.
if gc.Is64(n.Type) || gc.Is64(res.Type) || n.Left != nil && gc.Is64(n.Left.Type) {
switch n.Op {
// math goes to cgen64.
case gc.OMINUS,
gc.OCOM,
gc.OADD,
gc.OSUB,
gc.OMUL,
gc.OLROT,
gc.OLSH,
gc.ORSH,
gc.OAND,
gc.OOR,
gc.OXOR:
cgen64(n, res)
return
}
}
if nl != nil && gc.Isfloat[n.Type.Etype] && gc.Isfloat[nl.Type.Etype] {
cgen_float(n, res)
return
}
var a int
switch n.Op {
default:
gc.Dump("cgen", n)
gc.Fatal("cgen %v", gc.Oconv(int(n.Op), 0))
case gc.OREAL,
gc.OIMAG,
gc.OCOMPLEX:
gc.Fatal("unexpected complex")
return
// these call bgen to get a bool value
case gc.OOROR,
gc.OANDAND,
gc.OEQ,
gc.ONE,
gc.OLT,
gc.OLE,
gc.OGE,
gc.OGT,
gc.ONOT:
p1 := gc.Gbranch(obj.AJMP, nil, 0)
p2 := gc.Pc
gmove(gc.Nodbool(true), res)
p3 := gc.Gbranch(obj.AJMP, nil, 0)
gc.Patch(p1, gc.Pc)
bgen(n, true, 0, p2)
gmove(gc.Nodbool(false), res)
gc.Patch(p3, gc.Pc)
return
case gc.OPLUS:
cgen(nl, res)
return
case gc.OMINUS,
gc.OCOM:
a := optoas(int(n.Op), nl.Type)
// unary
var n1 gc.Node
gc.Tempname(&n1, nl.Type)
cgen(nl, &n1)
gins(a, nil, &n1)
gmove(&n1, res)
return
// symmetric binary
case gc.OAND,
gc.OOR,
gc.OXOR,
gc.OADD,
gc.OMUL:
a = optoas(int(n.Op), nl.Type)
if a == x86.AIMULB {
cgen_bmul(int(n.Op), nl, nr, res)
break
}
// symmetric binary
if nl.Ullman < nr.Ullman || nl.Op == gc.OLITERAL {
r := nl
nl = nr
nr = r
}
goto abop
// asymmetric binary
case gc.OSUB:
a = optoas(int(n.Op), nl.Type)
goto abop
case gc.OHMUL:
cgen_hmul(nl, nr, res)
case gc.OCONV:
if gc.Eqtype(n.Type, nl.Type) || gc.Noconv(n.Type, nl.Type) {
cgen(nl, res)
break
}
var n2 gc.Node
gc.Tempname(&n2, n.Type)
var n1 gc.Node
mgen(nl, &n1, res)
gmove(&n1, &n2)
gmove(&n2, res)
mfree(&n1)
case gc.ODOT,
gc.ODOTPTR,
gc.OINDEX,
gc.OIND,
gc.ONAME: // PHEAP or PPARAMREF var
var n1 gc.Node
igen(n, &n1, res)
gmove(&n1, res)
regfree(&n1)
case gc.OITAB:
var n1 gc.Node
igen(nl, &n1, res)
n1.Type = gc.Ptrto(gc.Types[gc.TUINTPTR])
gmove(&n1, res)
regfree(&n1)
// pointer is the first word of string or slice.
case gc.OSPTR:
if gc.Isconst(nl, gc.CTSTR) {
var n1 gc.Node
regalloc(&n1, gc.Types[gc.Tptr], res)
p1 := gins(x86.ALEAL, nil, &n1)
gc.Datastring(nl.Val.U.Sval, &p1.From)
gmove(&n1, res)
regfree(&n1)
break
}
var n1 gc.Node
igen(nl, &n1, res)
n1.Type = n.Type
gmove(&n1, res)
regfree(&n1)
case gc.OLEN:
if gc.Istype(nl.Type, gc.TMAP) || gc.Istype(nl.Type, gc.TCHAN) {
// map has len in the first 32-bit word.
// a zero pointer means zero length
var n1 gc.Node
gc.Tempname(&n1, gc.Types[gc.Tptr])
cgen(nl, &n1)
var n2 gc.Node
regalloc(&n2, gc.Types[gc.Tptr], nil)
gmove(&n1, &n2)
n1 = n2
gc.Nodconst(&n2, gc.Types[gc.Tptr], 0)
gins(optoas(gc.OCMP, gc.Types[gc.Tptr]), &n1, &n2)
p1 := gc.Gbranch(optoas(gc.OEQ, gc.Types[gc.Tptr]), nil, -1)
n2 = n1
n2.Op = gc.OINDREG
n2.Type = gc.Types[gc.TINT32]
gmove(&n2, &n1)
gc.Patch(p1, gc.Pc)
gmove(&n1, res)
regfree(&n1)
break
}
if gc.Istype(nl.Type, gc.TSTRING) || gc.Isslice(nl.Type) {
// both slice and string have len one pointer into the struct.
var n1 gc.Node
igen(nl, &n1, res)
n1.Type = gc.Types[gc.TUINT32]
n1.Xoffset += int64(gc.Array_nel)
gmove(&n1, res)
regfree(&n1)
break
}
gc.Fatal("cgen: OLEN: unknown type %v", gc.Tconv(nl.Type, obj.FmtLong))
case gc.OCAP:
if gc.Istype(nl.Type, gc.TCHAN) {
// chan has cap in the second 32-bit word.
// a zero pointer means zero length
var n1 gc.Node
gc.Tempname(&n1, gc.Types[gc.Tptr])
cgen(nl, &n1)
var n2 gc.Node
regalloc(&n2, gc.Types[gc.Tptr], nil)
gmove(&n1, &n2)
n1 = n2
gc.Nodconst(&n2, gc.Types[gc.Tptr], 0)
gins(optoas(gc.OCMP, gc.Types[gc.Tptr]), &n1, &n2)
p1 := gc.Gbranch(optoas(gc.OEQ, gc.Types[gc.Tptr]), nil, -1)
n2 = n1
n2.Op = gc.OINDREG
n2.Xoffset = 4
n2.Type = gc.Types[gc.TINT32]
gmove(&n2, &n1)
gc.Patch(p1, gc.Pc)
gmove(&n1, res)
regfree(&n1)
break
}
if gc.Isslice(nl.Type) {
var n1 gc.Node
igen(nl, &n1, res)
n1.Type = gc.Types[gc.TUINT32]
n1.Xoffset += int64(gc.Array_cap)
gmove(&n1, res)
regfree(&n1)
break
}
gc.Fatal("cgen: OCAP: unknown type %v", gc.Tconv(nl.Type, obj.FmtLong))
case gc.OADDR:
agen(nl, res)
case gc.OCALLMETH:
gc.Cgen_callmeth(n, 0)
cgen_callret(n, res)
case gc.OCALLINTER:
cgen_callinter(n, res, 0)
cgen_callret(n, res)
case gc.OCALLFUNC:
cgen_call(n, 0)
cgen_callret(n, res)
case gc.OMOD,
gc.ODIV:
cgen_div(int(n.Op), nl, nr, res)
case gc.OLSH,
gc.ORSH,
gc.OLROT:
cgen_shift(int(n.Op), n.Bounded, nl, nr, res)
}
return
abop: // asymmetric binary
if gc.Smallintconst(nr) {
var n1 gc.Node
mgen(nl, &n1, res)
var n2 gc.Node
regalloc(&n2, nl.Type, &n1)
gmove(&n1, &n2)
gins(a, nr, &n2)
gmove(&n2, res)
regfree(&n2)
mfree(&n1)
} else if nl.Ullman >= nr.Ullman {
var nt gc.Node
gc.Tempname(&nt, nl.Type)
cgen(nl, &nt)
var n2 gc.Node
mgen(nr, &n2, nil)
var n1 gc.Node
regalloc(&n1, nl.Type, res)
gmove(&nt, &n1)
gins(a, &n2, &n1)
gmove(&n1, res)
regfree(&n1)
mfree(&n2)
} else {
var n2 gc.Node
regalloc(&n2, nr.Type, res)
cgen(nr, &n2)
var n1 gc.Node
regalloc(&n1, nl.Type, nil)
cgen(nl, &n1)
gins(a, &n2, &n1)
regfree(&n2)
gmove(&n1, res)
regfree(&n1)
}
return
}