Show sym.c syntax highlighted
#include "c.h"
#include <stdio.h>
#define equalp(x) v.x == p->sym.u.c.v.x
struct table {
int level;
Table previous;
struct entry {
struct symbol sym;
struct entry *link;
} *buckets[256];
Symbol all;
};
#define HASHSIZE NELEMS(((Table)0)->buckets)
static struct table
cns = { CONSTANTS },
ext = { GLOBAL },
ids = { GLOBAL },
tys = { GLOBAL };
Table constants = &cns;
Table externals = &ext;
Table identifiers = &ids;
Table globals = &ids;
Table types = &tys;
Table labels;
int level = GLOBAL;
static int tempid;
List loci, symbols;
Table table(Table tp, int level) {
Table new;
NEW0(new, FUNC);
new->previous = tp;
new->level = level;
if (tp)
new->all = tp->all;
return new;
}
void foreach(Table tp, int lev, void (*apply)(Symbol, void *), void *cl) {
assert(tp);
while (tp && tp->level > lev)
tp = tp->previous;
if (tp && tp->level == lev) {
Symbol p;
Coordinate sav;
sav = src;
for (p = tp->all; p && p->scope == lev; p = p->up) {
src = p->src;
(*apply)(p, cl);
}
src = sav;
}
}
void enterscope(void) {
if (++level == LOCAL)
tempid = 0;
}
void exitscope(void) {
rmtypes(level);
if (types->level == level)
types = types->previous;
if (identifiers->level == level) {
if (Aflag >= 2) {
int n = 0;
Symbol p;
for (p = identifiers->all; p && p->scope == level; p = p->up)
if (++n > 127) {
warning("more than 127 identifiers declared in a block\n");
break;
}
}
identifiers = identifiers->previous;
}
assert(level >= GLOBAL);
--level;
}
Symbol install(const char *name, Table *tpp, int level, int arena) {
Table tp = *tpp;
struct entry *p;
unsigned h = (unsigned long)name&(HASHSIZE-1);
assert(level == 0 || level >= tp->level);
if (level > 0 && tp->level < level)
tp = *tpp = table(tp, level);
NEW0(p, arena);
p->sym.name = (char *)name;
p->sym.scope = level;
p->sym.up = tp->all;
tp->all = &p->sym;
p->link = tp->buckets[h];
tp->buckets[h] = p;
return &p->sym;
}
Symbol relocate(const char *name, Table src, Table dst) {
struct entry *p, **q;
Symbol *r;
unsigned h = (unsigned long)name&(HASHSIZE-1);
for (q = &src->buckets[h]; *q; q = &(*q)->link)
if (name == (*q)->sym.name)
break;
assert(*q);
/*
Remove the entry from src's hash chain
and from its list of all symbols.
*/
p = *q;
*q = (*q)->link;
for (r = &src->all; *r && *r != &p->sym; r = &(*r)->up)
;
assert(*r == &p->sym);
*r = p->sym.up;
/*
Insert the entry into dst's hash chain
and into its list of all symbols.
Return the symbol-table entry.
*/
p->link = dst->buckets[h];
dst->buckets[h] = p;
p->sym.up = dst->all;
dst->all = &p->sym;
return &p->sym;
}
Symbol lookup(const char *name, Table tp) {
struct entry *p;
unsigned h = (unsigned long)name&(HASHSIZE-1);
assert(tp);
do
for (p = tp->buckets[h]; p; p = p->link)
if (name == p->sym.name)
return &p->sym;
while ((tp = tp->previous) != NULL);
return NULL;
}
int genlabel(int n) {
static int label = 1;
label += n;
return label - n;
}
Symbol findlabel(int lab) {
struct entry *p;
unsigned h = lab&(HASHSIZE-1);
for (p = labels->buckets[h]; p; p = p->link)
if (lab == p->sym.u.l.label)
return &p->sym;
NEW0(p, FUNC);
p->sym.name = stringd(lab);
p->sym.scope = LABELS;
p->sym.up = labels->all;
labels->all = &p->sym;
p->link = labels->buckets[h];
labels->buckets[h] = p;
p->sym.generated = 1;
p->sym.u.l.label = lab;
(*IR->defsymbol)(&p->sym);
return &p->sym;
}
Symbol constant(Type ty, Value v) {
struct entry *p;
unsigned h = v.u&(HASHSIZE-1);
ty = unqual(ty);
for (p = constants->buckets[h]; p; p = p->link)
if (eqtype(ty, p->sym.type, 1))
switch (ty->op) {
case INT: if (equalp(i)) return &p->sym; break;
case UNSIGNED: if (equalp(u)) return &p->sym; break;
case FLOAT: if (equalp(d)) return &p->sym; break;
case FUNCTION: if (equalp(g)) return &p->sym; break;
case ARRAY:
case POINTER: if (equalp(p)) return &p->sym; break;
default: assert(0);
}
NEW0(p, PERM);
p->sym.name = vtoa(ty, v);
p->sym.scope = CONSTANTS;
p->sym.type = ty;
p->sym.sclass = STATIC;
p->sym.u.c.v = v;
p->link = constants->buckets[h];
p->sym.up = constants->all;
constants->all = &p->sym;
constants->buckets[h] = p;
if (ty->u.sym && !ty->u.sym->addressed)
(*IR->defsymbol)(&p->sym);
p->sym.defined = 1;
return &p->sym;
}
Symbol intconst(int n) {
Value v;
v.i = n;
return constant(inttype, v);
}
Symbol genident(int scls, Type ty, int lev) {
Symbol p;
NEW0(p, lev >= LOCAL ? FUNC : PERM);
p->name = stringd(genlabel(1));
p->scope = lev;
p->sclass = scls;
p->type = ty;
p->generated = 1;
if (lev == GLOBAL)
(*IR->defsymbol)(p);
return p;
}
Symbol temporary(int scls, Type ty) {
Symbol p;
NEW0(p, FUNC);
p->name = stringd(++tempid);
p->scope = level < LOCAL ? LOCAL : level;
p->sclass = scls;
p->type = ty;
p->temporary = 1;
p->generated = 1;
return p;
}
Symbol newtemp(int sclass, int tc, int size) {
Symbol p = temporary(sclass, btot(tc, size));
(*IR->local)(p);
p->defined = 1;
return p;
}
Symbol allsymbols(Table tp) {
return tp->all;
}
void locus(Table tp, Coordinate *cp) {
loci = append(cp, loci);
symbols = append(allsymbols(tp), symbols);
}
void use(Symbol p, Coordinate src) {
Coordinate *cp;
NEW(cp, PERM);
*cp = src;
p->uses = append(cp, p->uses);
}
/* findtype - find type ty in identifiers */
Symbol findtype(Type ty) {
Table tp = identifiers;
int i;
struct entry *p;
assert(tp);
do
for (i = 0; i < HASHSIZE; i++)
for (p = tp->buckets[i]; p; p = p->link)
if (p->sym.type == ty && p->sym.sclass == TYPEDEF)
return &p->sym;
while ((tp = tp->previous) != NULL);
return NULL;
}
/* mkstr - make a string constant */
Symbol mkstr(char *str) {
Value v;
Symbol p;
v.p = str;
p = constant(array(chartype, strlen(v.p) + 1, 0), v);
if (p->u.c.loc == NULL)
p->u.c.loc = genident(STATIC, p->type, GLOBAL);
return p;
}
/* mksymbol - make a symbol for name, install in &globals if sclass==EXTERN */
Symbol mksymbol(int sclass, const char *name, Type ty) {
Symbol p;
if (sclass == EXTERN)
p = install(string(name), &globals, GLOBAL, PERM);
else {
NEW0(p, PERM);
p->name = string(name);
p->scope = GLOBAL;
}
p->sclass = sclass;
p->type = ty;
(*IR->defsymbol)(p);
p->defined = 1;
return p;
}
/* vtoa - return string for the constant v of type ty */
char *vtoa(Type ty, Value v) {
char buf[50];
ty = unqual(ty);
switch (ty->op) {
case INT: return stringd(v.i);
case UNSIGNED: return stringf((v.u&~0x7FFF) ? "0x%X" : "%U", v.u);
case FLOAT: return stringf("%g", (double)v.d);
case ARRAY:
if (ty->type == chartype || ty->type == signedchar
|| ty->type == unsignedchar)
return v.p;
return stringf("%p", v.p);
case POINTER: return stringf("%p", v.p);
case FUNCTION: return stringf("%p", v.g);
}
assert(0); return NULL;
}
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