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complex constant multiply and divide

R=rsc
CC=golang-dev
https://golang.org/cl/217041
This commit is contained in:
Ken Thompson 2010-02-18 17:55:11 -08:00
parent d17ffb9753
commit fc010adcd7
5 changed files with 92 additions and 10 deletions

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@ -9,6 +9,7 @@ char *runtimeimport =
"func \"\".printfloat (? float64)\n"
"func \"\".printint (? int64)\n"
"func \"\".printuint (? uint64)\n"
"func \"\".printcomplex (? complex128)\n"
"func \"\".printstring (? string)\n"
"func \"\".printpointer (? any)\n"
"func \"\".printiface (? any)\n"

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@ -9,6 +9,8 @@ static Val tocplx(Val);
static Val toflt(Val);
static Val tostr(Val);
static Val copyval(Val);
static void cmplxmpy(Mpcplx *v, Mpcplx *rv);
static void cmplxdiv(Mpcplx *v, Mpcplx *rv);
/*
* truncate float literal fv to 32-bit or 64-bit precision
@ -614,9 +616,10 @@ evconst(Node *n)
mpsubfltflt(&v.u.cval->imag, &rv.u.cval->imag);
break;
case TUP(OMUL, CTCPLX):
goto illegal; // TODO
cmplxmpy(v.u.cval, rv.u.cval);
break;
case TUP(ODIV, CTCPLX):
goto illegal; // TODO
cmplxdiv(v.u.cval, rv.u.cval);
break;
case TUP(OEQ, CTNIL):
@ -793,6 +796,13 @@ unary:
mpnegflt(v.u.fval);
break;
case TUP(OPLUS, CTCPLX):
break;
case TUP(OMINUS, CTCPLX):
mpnegflt(&v.u.cval->real);
mpnegflt(&v.u.cval->imag);
break;
case TUP(ONOT, CTBOOL):
if(!v.u.bval)
goto settrue;
@ -1187,3 +1197,65 @@ convconst(Node *con, Type *t, Val *val)
fatal("convconst %lT constant", t);
}
// complex multiply v *= rv
// (a, b) * (c, d) = (a*c - b*d, b*c + a*d)
static void
cmplxmpy(Mpcplx *v, Mpcplx *rv)
{
Mpflt ac, bd, bc, ad;
mpmovefltflt(&ac, &v->real);
mpmulfltflt(&ac, &rv->real); // ac
mpmovefltflt(&bd, &v->imag);
mpmulfltflt(&bd, &rv->imag); // bd
mpmovefltflt(&bc, &v->imag);
mpmulfltflt(&bc, &rv->real); // bc
mpmovefltflt(&ad, &v->real);
mpmulfltflt(&ad, &rv->imag); // ad
mpmovefltflt(&v->real, &ac);
mpsubfltflt(&v->real, &bd); // ac-bd
mpmovefltflt(&v->imag, &bc);
mpaddfltflt(&v->imag, &ad); // bc+ad
}
// complex divide v /= rv
// (a, b) / (c, d) = ((a*c + b*d), (b*c - a*d))/(c*c + d*d)
static void
cmplxdiv(Mpcplx *v, Mpcplx *rv)
{
Mpflt ac, bd, bc, ad, cc_plus_dd;
mpmovefltflt(&cc_plus_dd, &rv->real);
mpmulfltflt(&cc_plus_dd, &rv->real); // cc
mpmovefltflt(&ac, &rv->imag);
mpmulfltflt(&ac, &rv->imag); // dd
mpaddfltflt(&cc_plus_dd, &ac); // cc+dd
mpmovefltflt(&ac, &v->real);
mpmulfltflt(&ac, &rv->real); // ac
mpmovefltflt(&bd, &v->imag);
mpmulfltflt(&bd, &rv->imag); // bd
mpmovefltflt(&bc, &v->imag);
mpmulfltflt(&bc, &rv->real); // bc
mpmovefltflt(&ad, &v->real);
mpmulfltflt(&ad, &rv->imag); // ad
mpmovefltflt(&v->real, &ac);
mpaddfltflt(&v->real, &bd); // ac+bd
mpdivfltflt(&v->real, &cc_plus_dd); // (ac+bd)/(cc+dd)
mpmovefltflt(&v->imag, &bc);
mpsubfltflt(&v->imag, &ad); // bc-ad
mpdivfltflt(&v->imag, &cc_plus_dd); // (bc+ad)/(cc+dd)
}

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@ -20,6 +20,7 @@ func printbool(bool)
func printfloat(float64)
func printint(int64)
func printuint(uint64)
func printcomplex(complex128)
func printstring(string)
func printpointer(any)
func printiface(any)

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@ -1370,6 +1370,10 @@ checkconv(Type *nt, Type *t, int explicit, int *op, int *et, char *desc)
if(isint[nt->etype] || isfloat[nt->etype])
return 1;
// between versions of complex
if(iscomplex[t->etype] || iscomplex[nt->etype])
return 1;
// to string
if(istype(t, TSTRING)) {
// integer rune

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@ -794,11 +794,13 @@ walkexpr(Node **np, NodeList **init)
case OCONV:
case OCONVNOP:
if(thechar == '5') {
if(isfloat[n->left->type->etype] && (n->type->etype == TINT64 || n->type->etype == TUINT64)) {
if(isfloat[n->left->type->etype] &&
(n->type->etype == TINT64 || n->type->etype == TUINT64)) {
n = mkcall("float64toint64", n->type, init, conv(n->left, types[TFLOAT64]));
goto ret;
}
if((n->left->type->etype == TINT64 || n->left->type->etype == TUINT64) && isfloat[n->type->etype]) {
if((n->left->type->etype == TINT64 || n->left->type->etype == TUINT64) &&
isfloat[n->type->etype]) {
n = mkcall("int64tofloat64", n->type, init, conv(n->left, types[TINT64]));
goto ret;
}
@ -1727,7 +1729,7 @@ walkprint(Node *nn, NodeList **init, int defer)
} else if(iscomplex[et]) {
if(defer) {
fmtprint(&fmt, "%%f");
t = types[TFLOAT64];
t = types[TCOMPLEX128];
} else
on = syslook("printcomplex", 0);
} else if(et == TBOOL) {
@ -2036,8 +2038,10 @@ convas(Node *n, NodeList **init)
if(lt == T || rt == T)
goto out;
if(isblank(n->left))
if(isblank(n->left)) {
defaultlit(&n->right, T);
goto out;
}
if(n->left->op == OINDEXMAP) {
n = mkcall1(mapfn("mapassign1", n->left->left->type), T, init,