ref: a63dd7c3e1fe8e41223a178f0b38a3354bd34d5e
dir: /cc2/arch/qbe/cgen.c/
/* See LICENSE file for copyright and license details. */
#include <assert.h>
#include <stdlib.h>
#include "arch.h"
#include "../../cc2.h"
#include "../../../inc/sizes.h"
enum sflags {
ISTMP = 1,
ISCONS = 2
};
static char opasmw[] = {
[OADD] = ASADDW,
[OSUB] = ASSUBW,
[OMUL] = ASMULW,
[OMOD] = ASMODW,
[ODIV] = ASDIVW,
[OSHL] = ASSHLW,
[OSHR] = ASSHRW,
[OLT] = ASLTW,
[OGT] = ASGTW,
[OLE] = ASLEW,
[OGE] = ASGEW,
[OEQ] = ASEQW,
[ONE] = ASNEW,
[OBAND] = ASBANDW,
[OBOR] = ASBORW,
[OBXOR] = ASBXORW,
[OCPL] = ASCPLW
};
static char opasml[] = {
[OADD] = ASADDL,
[OSUB] = ASSUBL,
[OMUL] = ASMULL,
[OMOD] = ASMODL,
[ODIV] = ASDIVL,
[OSHL] = ASSHLL,
[OSHR] = ASSHRL,
[OLT] = ASLTL,
[OGT] = ASGTL,
[OLE] = ASLEL,
[OGE] = ASGEL,
[OEQ] = ASEQL,
[ONE] = ASNEL,
[OBAND] = ASBANDL,
[OBOR] = ASBORL,
[OBXOR] = ASBXORL,
[OCPL] = ASCPLL
};
static char opasms[] = {
[OADD] = ASADDS,
[OSUB] = ASSUBS,
[OMUL] = ASMULS,
[OMOD] = ASMODS,
[ODIV] = ASDIVS,
[OSHL] = ASSHLS,
[OSHR] = ASSHRS,
[OLT] = ASLTS,
[OGT] = ASGTS,
[OLE] = ASLES,
[OGE] = ASGES,
[OEQ] = ASEQS,
[ONE] = ASNES,
[OBAND] = ASBANDS,
[OBOR] = ASBORS,
[OBXOR] = ASBXORS,
[OCPL] = ASCPLS
};
static char opasmd[] = {
[OADD] = ASADDD,
[OSUB] = ASSUBD,
[OMUL] = ASMULD,
[OMOD] = ASMODD,
[ODIV] = ASDIVD,
[OSHL] = ASSHLD,
[OSHR] = ASSHRD,
[OLT] = ASLTD,
[OGT] = ASGTD,
[OLE] = ASLED,
[OGE] = ASGED,
[OEQ] = ASEQD,
[ONE] = ASNED,
[OBAND] = ASBANDD,
[OBOR] = ASBORD,
[OBXOR] = ASBXORD,
[OCPL] = ASCPLD
};
extern Type int32type;
static Node *
tmpnode(Node *np)
{
Symbol *sym;
sym = getsym(TMPSYM);
sym->type = np->type;
sym->kind = STMP;
np->u.sym = sym;
np->op = OTMP;
np->flags |= ISTMP;
return np;
}
static Node *
load(Node *np, Node *new)
{
int op;
Type *tp;
tp = &np->type;
new->type = *tp;
tmpnode(new);
switch (tp->size) {
case 1:
op = ASLDB;
break;
case 2:
op = ASLDH;
break;
case 4:
op = (tp->flags & INTF) ? ASLDW : ASLDS;
break;
case 8:
op = (tp->flags & INTF) ? ASLDL : ASLDD;
break;
default:
abort();
}
code(op, new, np, NULL);
return new;
}
static Node *
assign(Node *to, Node *from)
{
Type *tp;
int op;
tp = &to->type;
switch (tp->size) {
case 1:
op = ASSTB;
break;
case 2:
op = ASSTH;
break;
case 4:
op = (tp->flags & INTF) ? ASSTW : ASSTS;
break;
case 8:
op = (tp->flags & INTF) ? ASSTL : ASSTD;
break;
default:
abort();
}
code(op, to, from, NULL);
return from;
}
static Node *rhs(Node *np, Node *new);
static Node *
lhs(Node *np, Node *new)
{
switch (np->op) {
case OMEM:
case OAUTO:
return np;
case OPTR:
return rhs(np->left, new);
default:
abort();
}
}
static void
bool(Node *np, Symbol *true, Symbol *false)
{
Node *l = np->left, *r = np->right;
Node ret, *ifyes, *ifno;
Symbol *label;
switch (np->op) {
case OAND:
label = newlabel();
bool(l, label, true);
setlabel(label);
bool(r, true, false);
break;
case OOR:
label = newlabel();
bool(l, true, label);
setlabel(label);
bool(r, true, false);
break;
default:
ifyes = label2node(true);
ifno = label2node(false);
rhs(l, &ret);
code(ASBRANCH, &ret, ifyes, ifno);
deltree(ifyes);
deltree(ifno);
break;
}
}
static Node *
function(void)
{
Symbol *p;
/* allocate stack space for parameters */
for (p = locals; p && (p->type.flags & PARF) != 0; p = p->next)
code(ASALLOC, label2node(p), NULL, NULL);
/* allocate stack space for local variables) */
for ( ; p && p->id != TMPSYM; p = p->next) {
if (p->kind != SAUTO)
continue;
code(ASALLOC, label2node(p), NULL, NULL);
}
/* store formal parameters in parameters */
for (p = locals; p; p = p->next) {
if ((p->type.flags & PARF) == 0)
break;
code(ASFORM, label2node(p), NULL, NULL);
}
return NULL;
}
static Node *
rhs(Node *np, Node *ret)
{
Node aux1, aux2, *phi, *l = np->left, *r = np->right;
Type *tp;
int off, op;
char *tbl;
Symbol *true, *false;
tp = &np->type;
switch (np->op) {
case OBFUN:
return function();
case ONOP:
case OEFUN:
return NULL;
case OCONST:
case OMEM:
case OAUTO:
return load(np, ret);
case OAND:
case OOR:
true = newlabel();
false = newlabel();
phi = label2node(newlabel());
ret->type = int32type;
tmpnode(ret);
bool(np, true, false);
setlabel(true);
assign(ret, constnode(1, &int32type));
code(ASJMP, NULL, phi, NULL);
setlabel(false);
assign(ret, constnode(0, &int32type));
setlabel(phi->u.sym);
deltree(phi);
return ret;
case OSHR:
case OMOD:
case ODIV:
case OLT:
case OGT:
case OLE:
case OGE:
/*
* unsigned version of operations are always +1 the
* signed version
*/
off = (tp->flags & SIGNF) == 0;
goto binary;
case OADD:
case OSUB:
case OMUL:
case OSHL:
case OBAND:
case OBOR:
case OBXOR:
case OEQ:
case ONE:
off = 0;
binary:
if (l->complex >= r->complex) {
rhs(l, &aux1);
rhs(r, &aux2);
} else {
rhs(r, &aux2);
rhs(l, &aux1);
}
switch (tp->size) {
case 4:
tbl = (tp->flags & INTF) ? opasmw : opasms;
break;
case 8:
tbl = (tp->flags & INTF) ? opasml : opasmd;
break;
default:
abort();
}
op = tbl[np->op] + off;
ret = tmpnode(ret);
code(op, ret, &aux1, &aux2);
return ret;
case OASSIG:
lhs(l, &aux1);
rhs(r, ret);
return assign(&aux1, ret);
default:
abort();
}
abort();
}
Node *
cgen(Node *np)
{
Node ret, *aux, *next, *phi, *ifyes, *ifno;
setlabel(np->label);
switch (np->op) {
case OJMP:
ifyes = label2node(np->u.sym);
code(ASJMP, NULL, ifyes, NULL);
deltree(ifyes);
break;
case OBRANCH:
next = np->next;
if (!next->label)
next->label = newlabel();
ifyes = label2node(np->u.sym);
ifno = label2node(next->label);
rhs(np->left, &ret);
code(ASBRANCH, &ret, ifyes, ifno);
deltree(ifyes);
deltree(ifno);
break;
case ORET:
aux = (np->left) ? rhs(np->left, &ret) : NULL;
code(ASRET, NULL, aux, NULL);
break;
default:
rhs(np, &ret);
break;
}
return NULL;
}
/*
* This is strongly influenced by
* http://plan9.bell-labs.com/sys/doc/compiler.ps (/sys/doc/compiler.ps)
* calculate addresability as follows
* AUTO => 11 value+fp
* REG => 11 reg
* STATIC => 11 (value)
* CONST => 11 $value
* These values of addressability are not used in the code generation.
* They are only used to calculate the Sethi-Ullman numbers. Since
* QBE is AMD64 targered we could do a better job there, and try to
* detect some of the complex addressing modes of these processors.
*/
Node *
sethi(Node *np)
{
Node *lp, *rp;
if (!np)
return np;
np->complex = 0;
np->address = 0;
lp = np->left;
rp = np->right;
switch (np->op) {
case OAUTO:
case OREG:
case OMEM:
case OCONST:
np->address = 11;
break;
case OCPL:
np->op = OAND;
rp = constnode(~(TUINT) 0, &np->type);
goto binary;
case OSNEG:
np->op = OSUB;
rp = lp;
lp = constnode(0, &np->type);
if ((np->type.flags & INTF) == 0)
lp->u.f = 0.0;
default:
binary:
lp = sethi(lp);
rp = sethi(rp);
break;
}
np->left = lp;
np->right = rp;
if (np->address > 10)
return np;
if (lp)
np->complex = lp->complex;
if (rp) {
int d = np->complex - rp->complex;
if (d == 0)
++np->complex;
else if (d < 0)
np->complex = rp->complex;
}
if (np->complex == 0)
++np->complex;
return np;
}