ref: 79f242a1b486146c944786b26b8b9a82a18670e2
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 lflags {
FORCE = 1 << 0,
LOADL = 1 << 1,
LOADR = 1 << 2
};
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
};
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;
}
/*
* load() load the address passed in a child of np in a temporary
* if it is not already in a temporay. It can be forced to load
* using the FORCE flag
*/
static Node *
load(Node *np, int flags)
{
int op;
Type *tp;
Node *child;
child = (flags & LOADL) ? np->left : np->right;
if (!child)
return NULL;
tp = &child->type;
if ((flags & FORCE) || !(child->flags & (ISTMP|ISCONS))) {
Node *new = tmpnode(newnode(OTMP));
new->type = *tp;
new->left = child;
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, child, NULL);
child = new;
}
return (flags & LOADL) ? (np->left = child) : (np->right = child);
}
static Node *
cast(Node *nd)
{
Type *ts, *td;
Node *tmp, *ns;
int op, disint, sisint;
extern Type uint32type, int32type;
ns = load(nd, LOADL);
td = &nd->type;
ts = &ns->type;
disint = (td->flags & INTF) != 0;
sisint = (ts->flags & INTF) != 0;
if (disint && sisint) {
if (td->size <= ts->size)
return nd;
assert(td->size == 4 || td->size == 8);
switch (ts->size) {
case 1:
op = (td->size == 4) ? ASEXTBW : ASEXTBL;
break;
case 2:
op = (td->size == 4) ? ASEXTHW : ASEXTHL;
break;
case 4:
op = ASEXTWL;
break;
default:
abort();
}
/*
* unsigned version of operations are always +1 the
* signed version
*/
op += (td->flags & SIGNF) == 0;
} else if (disint) {
/* conversion from float to int */
switch (ts->size) {
case 4:
op = (td->size == 8) ? ASSTOL : ASSTOW;
break;
case 8:
op = (td->size == 8) ? ASDTOL : ASDTOW;
break;
default:
abort();
}
/* TODO: Add signess */
} else if (sisint) {
/* conversion from int to float */
switch (ts->size) {
case 1:
case 2:
tmp = tmpnode(newnode(ONOP));
tmp->type = (ts->flags&SIGNF) ? int32type : uint32type;
tmp->left = ns;
nd->left = ns = cast(tmp);
case 4:
op = (td->size == 8) ? ASSWTOD : ASSWTOS;
break;
case 8:
op = (td->size == 8) ? ASSLTOD : ASSLTOS;
break;
default:
abort();
}
/* TODO: Add signess */
} else {
/* conversion from float to float */
op = (td->size == 4) ? ASEXTS : ASTRUNCD;
}
code(op, tmpnode(nd), ns, NULL);
return nd;
}
static Node *
call(Node *np)
{
int n, op;
Type *tp = &np->type;
Node **q, *tmp, *p, *pars[NR_FUNPARAM];
for (n = 0, p = np->right; p; p = p->right) {
cgen(p->left);
pars[n++] = load(p, LOADL);
}
switch (tp->size) {
case 0:
np->left = tmpnode(newnode(OTMP));
op = ASCALLW;
break;
case 1:
op = ASCALLB;
break;
case 2:
op = ASCALLH;
break;
case 4:
op = (tp->flags & INTF) ? ASCALLW : ASCALLS;
break;
case 8:
op = (tp->flags & INTF) ? ASCALLL : ASCALLD;
break;
default:
abort();
}
code(op, tmpnode(np), np->left, NULL);
for (q = pars; q < &pars[n]; ++q) {
op = (q == &pars[n-1]) ? ASPARE : ASPAR;
p = newnode(OTMP);
p->type = (*q)->type;
code(op, NULL, *q, tmpnode(p));
}
code(ASCALL, NULL, NULL, NULL);
return np;
}
static Node *
abbrev(Node *np)
{
Node *tmp;
if (np->u.subop == 0)
return np->right;
tmp = newnode(np->u.subop);
tmp->type = np->type;
tmp->right = np->right;
tmp->left = np->left;
return np->right = cgen(tmp);
}
static Node *
assign(Node *to, Node *from)
{
Type *tp = &to->type;
int op;
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 *
ternary(Node *np)
{
Symbol *yes, *no, *phi;
Node *ifyes, *ifno, *phinode, *colon;
tmpnode(np);
phi = newlabel();
yes = newlabel();
no = newlabel();
ifyes = label2node(yes);
ifno = label2node(no);
phinode = label2node(phi);
colon = np->right;
cgen(np->left);
code(ASBRANCH, load(np, LOADL), ifyes, ifno);
setlabel(yes);
cgen(colon->left);
assign(np, load(colon, LOADL));
code(ASJMP, NULL, phinode, NULL);
setlabel(no);
cgen(colon->right);
assign(np, load(colon, LOADR));
setlabel(phi);
deltree(ifyes);
deltree(ifno);
deltree(phinode);
return np;
}
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;
}
/* TODO: Fix "memory leaks" */
Node *
cgen(Node *np)
{
Node *ifyes, *ifno, *next;
Symbol *sym;
Type *tp;
int op, off;
char *tbl;
if (!np)
return NULL;
setlabel(np->label);
if (np->op != OCALL && np->op != OASK) {
np->left = cgen(np->left);
np->right = cgen(np->right);
}
tp = &np->type;
switch (np->op) {
case OSTRING:
abort();
case OBFUN:
return function();
case OEFUN:
return NULL;
case OCONST:
case OLABEL:
np->flags |= ISCONS;
case OMEM:
case OAUTO:
return np;
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:
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;
code(op, tmpnode(np), load(np, LOADL), load(np, LOADR));
return np;
case ONOP:
case OBLOOP:
case OELOOP:
return NULL;
case OCAST:
return cast(np);
case OADDR:
np->flags |= ISTMP;
np->op = OTMP;
np->u.sym = np->left->u.sym;
return np;
case OPTR:
load(np, LOADL);
load(np, LOADL|FORCE);
return np->left;
case OCPL:
case ONEG:
case OINC:
case ODEC:
abort();
case OASSIG:
abbrev(np);
return assign(np->left, load(np, LOADR));
case OCOMMA:
return np->right;
case OCALL:
return call(np);
case OFIELD:
case OAND:
case OOR:
abort();
case OASK:
return ternary(np);
case OBRANCH:
next = np->next;
load(np, LOADL);
if (!next->label)
next->label = newlabel();
ifyes = label2node(np->u.sym);
ifno = label2node(next->label);
op = ASBRANCH;
np = np->left;
goto emit_jump;
case OJMP:
ifyes = label2node(np->u.sym);
op = ASJMP;
np = ifno = NULL;
emit_jump:
code(op, np, ifyes, ifno);
deltree(ifyes);
deltree(ifno);
return NULL;
case ORET:
code(ASRET, NULL, load(np, LOADL), NULL);
return NULL;
case OCASE:
case ODEFAULT:
case OESWITCH:
case OBSWITCH:
default:
abort();
}
}
/*
* 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 here, 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;
default:
sethi(lp);
sethi(rp);
break;
}
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;
}