ref: dfc2beaa2c71a595983aefba6782ad412a4662b6
dir: /cc2/parser.c/
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "../inc/cc.h"
#include "../inc/sizes.h"
#include "arch.h"
#include "cc2.h"
#define MAXLINE 200
#define STACKSIZ 50
extern Type int8type, int16type, int32type, int64type,
uint8type, uint16type, uint32type, uint64type,
float32type, float64type, float80type,
booltype,
ptrtype,
voidtype,
elipsistype;
Type funtype = {
.flags = FUNF
};
union tokenop {
void *arg;
int op;
};
typedef void parsefun(char *, union tokenop);
static parsefun type, symbol, getname, unary, binary, ternary, call,
parameter, constant, composed, binit, einit,
jump, oreturn, loop, assign, ocase, odefault, casetbl;
typedef void evalfun(void);
static evalfun vardecl, beginfun, endfun, endpars, stmt,
array, aggregate, flddecl, labeldcl;
static struct decoc {
void (*eval)(void);
void (*parse)(char *token, union tokenop);
union tokenop u;
} optbl[] = { /* eval parse args */
[AUTO] = { vardecl, symbol, .u.op = OAUTO},
[REG] = { vardecl, symbol, .u.op = OREG},
[GLOB] = { vardecl, symbol, .u.op = OMEM},
[EXTRN] = { vardecl, symbol, .u.op = OMEM},
[PRIVAT] = { vardecl, symbol, .u.op = OMEM},
[LOCAL] = { vardecl, symbol, .u.op = OMEM},
[MEMBER] = { flddecl, symbol, .u.op = OMEM},
[LABEL] = { labeldcl, symbol, .u.op = OLABEL},
[INT8] = { NULL, type, .u.arg = &int8type},
[INT16] = { NULL, type, .u.arg = &int16type},
[INT32] = { NULL, type, .u.arg = &int32type},
[INT64] = { NULL, type, .u.arg = &int64type},
[UINT8] = { NULL, type, .u.arg = &uint8type},
[UINT16] = { NULL, type, .u.arg = &uint16type},
[UINT32] = { NULL, type, .u.arg = &uint32type},
[UINT64] = { NULL, type, .u.arg = &uint64type},
[FLOAT] = { NULL, type, .u.arg = &float32type},
[DOUBLE] = { NULL, type, .u.arg = &float64type},
[LDOUBLE] = { NULL, type, .u.arg = &float80type},
[VOID] = { NULL, type, .u.arg = &voidtype},
[BOOL] = { NULL, type, .u.arg = &booltype},
[POINTER] = { NULL, type, .u.arg = &ptrtype},
[ELLIPSIS] = { NULL, type, .u.arg = &elipsistype},
[FUNCTION] = { NULL, type, .u.arg = &funtype},
[VECTOR] = { array,composed, 0},
[UNION] = {aggregate,composed, 0},
[STRUCT] = {aggregate,composed, 0},
[ONAME] = { NULL, getname, 0},
['{'] = { beginfun, NULL, 0},
['}'] = { endfun, NULL, 0},
['('] = { NULL, binit, 0},
[')'] = { NULL, einit, 0},
[OEPARS] = { endpars, NULL, 0},
[OSTMT] = { stmt, NULL, 0},
[OCPL] = { NULL, unary, 0},
[ONEG] = { NULL, unary, 0},
[OADDR] = { NULL, unary, 0},
[OPTR] = { NULL, unary, 0},
[OCAST] = { NULL, unary, 0},
[OPAR ] = { NULL, unary, 0},
[OAND] = { NULL, binary, 0},
[OOR] = { NULL, binary, 0},
[OFIELD] = { NULL, binary, 0},
[OADD] = { NULL, binary, 0},
[OSUB] = { NULL, binary, 0},
[OMUL] = { NULL, binary, 0},
[OMOD] = { NULL, binary, 0},
[ODIV] = { NULL, binary, 0},
[OSHL] = { NULL, binary, 0},
[OSHR] = { NULL, binary, 0},
[OLT] = { NULL, binary, 0},
[OGT] = { NULL, binary, 0},
[OLE] = { NULL, binary, 0},
[OGE] = { NULL, binary, 0},
[OEQ] = { NULL, binary, 0},
[ONE] = { NULL, binary, 0},
[OBAND] = { NULL, binary, 0},
[OBOR] = { NULL, binary, 0},
[OBXOR] = { NULL, binary, 0},
[OCOMMA] = { NULL, binary, 0},
[OASSIG] = { NULL, assign, 0},
[OASK] = { NULL, ternary, 0},
[OCALL] = { NULL, call, 0},
[OCONST] = { NULL,constant, 0},
[OJMP] = { NULL, jump, 0},
[OBRANCH] = { NULL, jump, 0},
[ORET] = { NULL, oreturn, 0},
[OBLOOP] = { NULL, loop, 0},
[OELOOP] = { NULL, loop, 0},
[OCASE] = { NULL, jump, 0},
[OSWITCH] = { NULL, jump, 0},
[ODEFAULT] = { NULL,odefault, 0},
[OTABLE] = { NULL, casetbl, 0}
};
static int sclass, inpars, ininit, endf, lineno;
static Node *stmtp;
static void *stack[STACKSIZ], **sp = stack;
static void
push(void *elem)
{
if (sp == stack[STACKSIZ])
error(ESTACKO);
*sp++ = elem;
}
static void *
pop(void)
{
if (sp == stack)
error(ESTACKU);
return *--sp;
}
static int
empty(void)
{
return sp == stack;
}
static void
type(char *token, union tokenop u)
{
push(u.arg);
}
static void
composed(char *token, union tokenop u)
{
Symbol *sym;
sym = getsym(atoi(token+1));
push(&sym->type);
}
static void
getname(char *t, union tokenop u)
{
push((*++t) ? xstrdup(t) : NULL);
}
static void
symbol(char *token, union tokenop u)
{
Node *np;
sclass = *token++;
np = newnode();
np->u.sym = getsym(atoi(token));
np->op = u.op;
push(np);
}
static Type *
gettype(char *token)
{
struct decoc *dp;
dp = &optbl[*token];
if (!dp->parse)
error(ESYNTAX);
(*dp->parse)(token, dp->u);
return pop();
}
static void
constant(char *token, union tokenop u)
{
static char letters[] = "0123456789ABCDEF";
Node *np = newnode();
TUINT v;
unsigned c;
++token;
if (*token == OSTRING) {
++token;
np->op = OSTRING;
np->type.flags = STRF;
np->type.size = strlen(token);
np->type.align = int8type.align;
np->u.s = xstrdup(token);
} else {
np->op = OCONST;
np->type = *gettype(token++);
for (v = 0; c = *token++; v += c) {
v <<= 4;
c = strchr(letters, c) - letters;
}
np->u.i = v;
}
push(np);
}
static void
assign(char *token, union tokenop u)
{
int c, op = *token++;
Node *np = newnode();
switch (*token) {
case ODIV:
case OMOD:
case OADD:
case OSUB:
case OSHL:
case OSHR:
case OBAND:
case OBXOR:
case OBOR:
case OINC:
case ODEC:
c = *token++;
break;
default:
c = 0;
break;
}
np->u.subop = c;
np->op = op;
np->type = *gettype(token);
np->right = pop();
np->left = pop();
push(np);
}
static void
ternary(char *token, union tokenop u)
{
Node *ask, *colon;
Type *tp;
tp = gettype(++token);
colon = newnode();
colon->op = OCOLON;
colon->right = pop();
colon->left = pop();
ask = newnode();
ask->op = OASK;
ask->type = *tp;
ask->left = pop();
push(ask);
}
static Node *
eval(char *tok)
{
struct decoc *dp;
do {
dp = &optbl[*tok];
if (!dp->parse)
break;
(*dp->parse)(tok, dp->u);
} while (tok = strtok(NULL, "\t\n"));
}
static int
nextline(void)
{
char line[MAXLINE];
size_t len;
int c;
void (*fun)(void);
repeat:
++lineno;
if (!fgets(line, sizeof(line), stdin))
return 0;
if ((len = strlen(line)) == 0 || line[0] == '\n')
goto repeat;
if (line[len-1] != '\n')
error(ELNLINE);
line[len-1] = '\0';
c = *line;
eval(strtok(line, "\t\n"));
if ((fun = *optbl[c].eval) != NULL)
(*fun)();
if (sp != stack)
error(ESTACKA);
return 1;
}
static void
oreturn(char *token, union tokenop u)
{
Node *np;
np = newnode();
np->op = *token;
eval(strtok(NULL, "\t\n"));
if (!empty())
np->left = pop();
push(np);
}
static void
jump(char *token, union tokenop u)
{
Node *np, *aux;
np = newnode();
np->op = *token;
eval(strtok(NULL, "\t\n"));
if (*token != OJMP)
np->left = pop();
aux = pop();
np->u.sym = aux->u.sym;
delnode(aux);
push(np);
}
static void
casetbl(char *token, union tokenop u)
{
Node *np, *aux;
np = newnode();
np->op = *token;
eval(strtok(NULL, "\t\n"));
np->left = pop();
push(np);
}
static void
odefault(char *token, union tokenop u)
{
Node *np;
np = newnode();
np->op = *token;
eval(strtok(NULL, "\t\n"));
np->left = pop();
push(np);
}
static void
loop(char *token, union tokenop u)
{
Node *np;
np = newnode();
np->op = *token;
push(np);
}
static void
unary(char *token, union tokenop u)
{
Node *np = newnode();
np->op = *token++;
np->type = *gettype(token);
np->left = pop();
np->right = NULL;
push(np);
}
static void
call(char *token, union tokenop u)
{
Node *np, *par, *fun;
for (par = NULL;; par = np) {
np = pop();
if (np->op != OPAR)
break;
np->right = par;
}
fun = newnode();
fun->op = *token++;
fun->type = *gettype(token);
fun->left = np;
fun->right = par;
push(fun);
}
static void
binary(char *token, union tokenop u)
{
Node *np = newnode();
np->op = *token++;
np->type = *gettype(token);
np->right = pop();
np->left = pop();
push(np);
}
static void
binit(char *token, union tokenop u)
{
ininit = 1;
}
static void
einit(char *token, union tokenop u)
{
ininit = 0;
endinit();
}
static void
endpars(void)
{
if (!curfun || !inpars)
error(ESYNTAX);
inpars = 0;
}
static void
aggregate(void)
{
Node *align, *size;
char *name;
Type *tp;
Symbol *sym;
align = pop();
size = pop();
name = pop();
tp = pop();
tp->size = size->u.i;
tp->align = align->u.i;
/*
* type is the first field of Symbol so we can obtain the
* address of the symbol from the address of the type.
* We have to do this because composed returns the pointer
* to the type, but in this function we also need the
* symbol to store the name.
*/
sym = (Symbol *) tp;
sym->name = name;
delnode(align);
delnode(size);
}
static void
array(void)
{
Type *tp, *base;
Node *size;
size = pop();
base = pop();
tp = pop();
tp->size = size->u.i;
tp->align = base->align;
delnode(size);
}
static void
decl(Symbol *sym)
{
Type *tp = &sym->type;
if (tp->flags & FUNF) {
curfun = sym;
} else {
switch (sym->kind) {
case EXTRN:
case GLOB:
case PRIVAT:
case LOCAL:
defglobal(sym);
break;
case AUTO:
case REG:
if (!curfun)
error(ESYNTAX);
((inpars) ? defpar : defvar)(sym);
break;
default:
abort();
}
}
}
static void
vardecl(void)
{
Type *tp;
Node *np;
Symbol *sym;
char *name;
name = pop();
tp = pop();
np = pop();
sym = np->u.sym;
/*
* We have to free sym->name because in tentative declarations
* we can have multiple declarations of the same symbol, and in
* this case our parser will allocate twice the memory
*/
free(sym->name);
sym->name = name;
sym->type = *tp;
sym->kind = sclass;
if (ininit)
sym->type.flags |= INITF;
decl(sym);
delnode(np);
}
static void
flddecl(void)
{
Node *off, *np;
char *name;
Type *tp;
Symbol *sym;
off = pop();
name = pop();
tp = pop();
np = pop();
sym = np->u.sym;
sym->u.off = off->u.i;
sym->name = name;
sym->type = *tp;
delnode(np);
delnode(off);
}
static void
labeldcl(void)
{
Node *np;
Symbol *sym;
np = pop();
sym = np->u.sym;
delnode(np);
nextline();
stmtp->label = sym;
sym->u.label = stmtp;
}
static void
addstmt(Node *np)
{
if (!curfun->u.label)
curfun->u.label = np;
else
stmtp->stmt = np;
stmtp = np;
}
static void
stmt(void)
{
Node *np;
np = pop();
if (ininit) {
data(np);
deltree(np);
return;
}
addstmt(np);
}
static void
beginfun(void)
{
inpars = 1;
pushctx();
}
static void
endfun(void)
{
endf = 1;
}
void
parse(void)
{
cleannodes(); /* remove code of previous function */
popctx(); /* remove context of previous function */
curfun = NULL;
endf = 0;
while (!endf && nextline())
/* nothing */;
if (ferror(stdin))
error(EFERROR, strerror(errno));
}