mirrors/tinycc
1
0
Fork 0
mirror of https://github.com/frida/tinycc synced 2024-11-28 10:33:07 +03:00
Code Issues Packages Projects Releases Wiki Activity
9a8dfaac35
tinycc/tcc.c
bellard 9a8dfaac35 added comments + correct error reporting
2001-10-28 15:20:12 +00:00

1076 lines
24 KiB
C
Raw Blame History

#include <stdio.h>
#define TEXT_SIZE 20000
#define DATA_SIZE 2000
#define SYM_TABLE_SIZE 10000
#define VAR_TABLE_SIZE 4096
/* vac: offset of variables
vat: type of variables
loc : local variable index
glo : global variable index
parm : parameter variable index
ind : output code ptr
lsym: loop symbol stack
rsym: return symbol
prog: output code
astk: arg position stack
*/
int tok, *vac, *vat, *lsym, rsym,
prog, ind, loc, glo, file, vt,
vc, *macro_stack, *macro_stack_ptr, line_num;
char *idtable, *idptr, *idlast, *filename;
/* The current value can be: */
#define VT_CONST 0x0002 /* constant in vc */
#define VT_VAR 0x0004 /* value is in eax */
#define VT_LOCAL 0x0008 /* offset on stack */
#define VT_LVAL 0x0010 /* const or var is an lvalue */
#define VT_CMP 0x0020 /* the value is stored in processor flags (in vc) */
#define VT_FORWARD 0x0040 /* value is forward reference (only used for functions) */
#define VT_JMP 0x0080 /* value is the consequence of jmp. bit 0 is set if inv */
#define VT_LVALN -17 /* ~VT_LVAL */
/*
*
* VT_FUNC indicates a function. The return type is the stored type. A
* function pointer is stored as a 'char' pointer.
*
* If VT_PTRMASK is non nul, then it indicates the number of pointer
* iterations to reach the basic type.
*
* Basic types:
*
* VT_BYTE indicate a char
*
*
* otherwise integer type is assumed.
* */
#define VT_BYTE 0x00001 /* byte pointer. HARDCODED VALUE */
#define VT_PTRMASK 0x00f00 /* pointer mask */
#define VT_PTRINC 0x00100 /* pointer increment */
#define VT_FUNC 0x01000 /* function type */
#define VT_TYPE 0x01f01 /* type mask */
#define VT_TYPEN 0xffffe0fe /* ~VT_TYPE */
#define VT_FUNCN -4097
/* Special infos */
#define VT_DEFINE 0x02000 /* special value for #defined symbols */
/* token values */
#define TOK_INT 256
#define TOK_VOID 257
#define TOK_CHAR 258
#define TOK_IF 259
#define TOK_ELSE 260
#define TOK_WHILE 261
#define TOK_BREAK 262
#define TOK_RETURN 263
#define TOK_DEFINE 264
#define TOK_MAIN 265
#define TOK_FOR 266
#define TOK_EQ 0x94 /* warning: depend on asm code */
#define TOK_NE 0x95 /* warning: depend on asm code */
#define TOK_LT 0x9c /* warning: depend on asm code */
#define TOK_GE 0x9d /* warning: depend on asm code */
#define TOK_LE 0x9e /* warning: depend on asm code */
#define TOK_GT 0x9f /* warning: depend on asm code */
#define TOK_LAND 0xa0
#define TOK_LOR 0xa1
#define TOK_DEC 0xa2
#define TOK_MID 0xa3 /* inc/dec, to void constant */
#define TOK_INC 0xa4
#define TOK_SHL 0xe0 /* warning: depend on asm code */
#define TOK_SHR 0xf8 /* warning: depend on asm code */
#ifdef TINY
#define expr_eq() expr()
#endif
int inp()
{
#if 0
int c;
c = fgetc(file);
printf("c=%c\n", c);
return c;
#else
return fgetc(file);
#endif
}
int isid(c)
{
return (c >= 'a' & c <= 'z') |
(c >= 'A' & c <= 'Z') |
c == '_';
}
int isnum(c)
{
return c >= '0' & c <= '9';
}
#ifndef TINY
/* XXX: use stderr ? */
void error(char *msg)
{
printf("%s:%d: %s\n", filename, line_num, msg);
exit(1);
}
void warning(char *msg)
{
printf("%s:%d: warning: %s\n", filename, line_num, msg);
}
void skip(c)
{
if (tok != c) {
printf("%s:%d: '%c' expected\n", filename, line_num, c);
exit(1);
}
next();
}
void test_lvalue()
{
if (!(vt & VT_LVAL))
error("lvalue expected\n");
}
#else
#define skip(c) next()
#define test_lvalue()
#endif
void next()
{
int c, v;
char *q, *p;
while(1) {
c = inp();
#ifndef TINY
if (c == '/') {
/* comments */
c = inp();
if (c == '/') {
/* single line comments */
while (c != '\n')
c = inp();
} else if (c == '*') {
/* comments */
while ((c = inp()) >= 0) {
if (c == '*') {
c = inp();
if (c == '/') {
c = ' ';
break;
} else if (c == '*')
ungetc(c, file);
} else if (c == '\n')
line_num++;
}
} else {
ungetc(c, file);
c = '/';
break;
}
} else
#endif
if (c == 35) {
/* preprocessor: we handle only define */
next();
if (tok == TOK_DEFINE) {
next();
/* now tok is the macro symbol */
vat[tok] = VT_DEFINE;
vac[tok] = ftell(file);
}
/* ignore preprocessor or shell */
while (c != '\n')
c = inp();
}
if (c == '\n') {
/* end of line : check if we are in macro state. if so,
pop new file position */
if (macro_stack_ptr > macro_stack)
fseek(file, *--macro_stack_ptr, 0);
else
line_num++;
} else if (c != ' ' & c != 9)
break;
}
if (isid(c)) {
q = idptr;
idlast = q;
while(isid(c) | isnum(c)) {
*q++ = c;
c = inp();
}
*q++ = '\0';
ungetc(c, file);
p = idtable;
tok = 256;
while (p < idptr) {
if (strcmp(p, idptr) == 0)
break;
while (*p++);
tok++;
}
/* if not found, add symbol */
if (p == idptr)
idptr = q;
/* eval defines */
if (vat[tok] & VT_DEFINE) {
*macro_stack_ptr++ = ftell(file);
fseek(file, vac[tok], 0);
next();
}
} else {
#ifdef TINY
q = "<=\236>=\235!=\225++\244--\242==\224";
#else
q = "<=\236>=\235!=\225&&\240||\241++\244--\242==\224<<\340>>\370";
#endif
/* two chars */
v = inp();
while (*q) {
if (*q == c & q[1] == v) {
tok = q[2] & 0xff;
return;
}
q = q + 3;
}
ungetc(v, file);
/* single char substitutions */
if (c == '<')
tok = TOK_LT;
else if (c == '>')
tok = TOK_GT;
else
tok = c;
}
}
void g(c)
{
*(char *)ind++ = c;
}
void o(c)
{
while (c) {
g(c);
c = c / 256;
}
}
/* output a symbol and patch all calls to it */
void gsym(t)
{
int n;
while (t) {
n = *(int *)t; /* next value */
*(int *)t = ind - t - 4;
t = n;
}
}
/* psym is used to put an instruction with a data field which is a
reference to a symbol. It is in fact the same as oad ! */
#define psym oad
/* instruction + 4 bytes data. Return the address of the data */
int oad(c, s)
{
o(c);
*(int *)ind = s;
s = ind;
ind = ind + 4;
return s;
}
void vset(t, v)
{
vt = t;
vc = v;
}
/* generate a value in eax from vt and vc */
void gv()
{
#ifndef TINY
int t;
#endif
if (vt & VT_LVAL) {
if ((vt & VT_TYPE) == VT_BYTE)
o(0xbe0f); /* movsbl x, %eax */
else
o(0x8b); /* movl x,%eax */
if (vt & VT_CONST)
oad(0x05, vc);
else if (vt & VT_LOCAL)
oad(0x85, vc);
else
g(0x00);
} else {
if (vt & VT_CONST) {
oad(0xb8, vc); /* mov $xx, %eax */
} else if (vt & VT_LOCAL) {
oad(0x858d, vc); /* lea xxx(%ebp), %eax */
} else if (vt & VT_CMP) {
oad(0xb8, 0); /* mov $0, %eax */
o(0x0f); /* setxx %al */
o(vc);
o(0xc0);
}
#ifndef TINY
else if (vt & VT_JMP) {
t = vt & 1;
oad(0xb8, t); /* mov $1, %eax */
oad(0xe9, 5); /* jmp after */
gsym(vc);
oad(0xb8, t ^ 1); /* mov $0, %eax */
}
#endif
}
vt = (vt & VT_TYPE) | VT_VAR;
}
/* generate a test. set 'inv' to invert test */
/* XXX: handle constant */
int gtst(inv, t)
{
if (vt & VT_CMP) {
/* fast case : can jump directly since flags are set */
g(0x0f);
t = psym((vc - 16) ^ inv, t);
} else
#ifndef TINY
if (vt & VT_JMP) {
/* && or || optimization */
if ((vt & 1) == inv)
t = vc;
else {
t = psym(0xe9, t);
gsym(vc);
}
} else
if ((vt & (VT_CONST | VT_LVAL)) == VT_CONST) {
/* constant jmp optimization */
if ((vc != 0) != inv)
t = psym(0xe9, t);
} else
#endif
{
gv();
o(0xc085); /* test %eax, %eax */
g(0x0f);
t = psym(0x85 ^ inv, t);
}
return t;
}
/* return the size in bytes of a given type */
int type_size(t)
{
if ((t & VT_PTRMASK) > VT_PTRINC | (t & VT_TYPE) == VT_PTRINC)
return 4;
else
return 1;
}
#define POST_ADD 0x1000
#define PRE_ADD 0
/* a defines POST/PRE add. c is the token ++ or -- */
void inc(a, c)
{
test_lvalue();
vt = vt & VT_LVALN;
gv();
o(0x018bc189); /* movl %eax, %ecx ; mov (%ecx), %eax */
o(0x408d | a); /* leal x(%eax), %eax/%edx */
g((c - TOK_MID) * type_size(vt));
o(0x0189 | a); /* mov %eax/%edx, (%ecx) */
}
/* XXX: handle ptr sub and 'int + ptr' case (only 'ptr + int' handled) */
/* XXX: handle constant propagation (need to track live eax) */
void gen_op(op, l)
{
int t;
gv();
t = vt;
o(0x50); /* push %eax */
next();
if (l < 0)
expr();
else
sum(l);
gv();
o(0x59); /* pop %ecx */
if (op == '+' | op == '-') {
/* XXX: incorrect for short (futur!) */
if (type_size(t) == 4)
o(0x02e0c1); /* shl $2, %eax */
if (op == '-')
o(0xd8f7); /* neg %eax */
o(0xc801); /* add %ecx, %eax */
vt = t;
} else if (op == '&')
o(0xc821);
else if (op == '^')
o(0xc831);
else if (op == '|')
o(0xc809);
else if (op == '*')
o(0xc1af0f); /* imul %ecx, %eax */
#ifndef TINY
else if (op == TOK_SHL | op == TOK_SHR) {
o(0xd391); /* xchg %ecx, %eax, shl/sar %cl, %eax */
o(op);
}
#endif
else if (op == '/' | op == '%') {
o(0x91); /* xchg %ecx, %eax */
o(0xf9f799); /* cltd, idiv %ecx, %eax */
if (op == '%')
o(0x92); /* xchg %edx, %eax */
} else {
o(0xc139); /* cmp %eax,%ecx */
vset(VT_CMP, op);
}
}
/* return 0 if no type declaration. otherwise, return the basic type
and skip it.
XXX: A '2' is ored to ensure non zero return if int type.
*/
int ist()
{
int t;
if (tok == TOK_INT | tok == TOK_CHAR | tok == TOK_VOID) {
t = tok;
next();
return (t != TOK_INT) | 2;
} else {
return 0;
}
}
/* Read a type declaration (except basic type), and return the
type. If v is true, then also put variable name in 'vc' */
int typ(v,t)
{
int u, p, n;
t = t & -3; /* suppress the ored '2' */
while (tok == '*') {
next();
t = t + VT_PTRINC;
}
/* recursive type */
/* XXX: incorrect if abstract type for functions (e.g. 'int ()') */
if (tok == '(') {
next();
u = typ(v, 0);
skip(')');
} else {
u = 0;
/* type identifier */
if (v) {
vc = tok;
next();
}
}
/* function declaration */
if (tok == '(') {
next();
p = 4;
n = vc; /* must save vc there */
while (tok != ')') {
/* read param name and compute offset */
if (t = ist())
t = typ(1, t); /* XXX: should accept both arg/non arg if v == 0 */
else {
vc = tok;
t = 0;
next();
}
p = p + 4;
vat[vc] = VT_LOCAL | VT_LVAL | t;
vac[vc] = p;
if (tok == ',')
next();
}
next(); /* skip ')' */
vc = n;
if (u)
t = u + VT_BYTE;
else
t = t | VT_FUNC;
}
return t;
}
/* read a number in base b */
int getn(c, b)
{
int n, t;
n = 0;
#ifndef TINY
while (1) {
if (c >= 'a')
t = c - 'a' + 10;
else if (c >= 'A')
t = c - 'A' + 10;
else
t = c - '0';
if (t < 0 | t >= b)
break;
n = n * b + t;
c = inp();
}
#else
while (isnum(c)) {
n = n * b + c - '0';
c = inp();
}
#endif
ungetc(c, file);
return n;
}
int getq(n)
{
if (n == '\\') {
n = inp();
if (n == 'n')
n = '\n';
#ifndef TINY
else if (n == 'r')
n = '\r';
else if (n == 't')
n = '\t';
#endif
else if (isnum(n))
n = getn(n, 8);
}
return n;
}
void unary()
{
int n, t, ft, fc, p;
if (isnum(tok)) {
/* number */
#ifndef TINY
t = 10;
if (tok == '0') {
t = 8;
tok = inp();
if (tok == 'x') {
t = 16;
tok = inp();
}
}
vset(VT_CONST, getn(tok, t));
#else
vset(VT_CONST, getn(tok, 10));
#endif
next();
} else
#ifndef TINY
if (tok == '\'') {
vset(VT_CONST, getq(inp()));
next(); /* skip char */
skip('\'');
} else
#endif
if (tok == '\"') {
vset(VT_CONST | VT_PTRINC | VT_BYTE, glo);
while (tok == '\"') {
while((n = inp()) != 34) {
*(char *)glo = getq(n);
glo++;
}
next();
}
*(char *)glo = 0;
glo = (glo + 4) & -4; /* align heap */
} else {
t = tok;
next();
if (t == '(') {
/* cast ? */
if (t = ist()) {
ft = typ(0, t);
skip(')');
unary();
vt = (vt & VT_TYPEN) | ft;
} else {
expr();
skip(')');
}
} else if (t == '*') {
unary();
if (vt & VT_LVAL)
gv();
#ifndef TINY
if (!(vt & VT_PTRMASK))
error("pointer expected");
#endif
vt = (vt - VT_PTRINC) | VT_LVAL;
} else if (t == '&') {
unary();
test_lvalue();
vt = (vt & VT_LVALN) + VT_PTRINC;
} else
#ifndef TINY
if (t == '!') {
unary();
if (vt & VT_CMP)
vc = vc ^ 1;
else
vset(VT_JMP, gtst(1, 0));
} else
if (t == '~') {
unary();
if ((vt & (VT_CONST | VT_LVAL)) == VT_CONST)
vc = ~vc;
else {
gv();
o(0xd0f7);
}
} else
if (t == '+') {
unary();
} else
#endif
if (t == TOK_INC | t == TOK_DEC) {
unary();
inc(PRE_ADD, t);
} else if (t == '-') {
unary();
if ((vt & (VT_CONST | VT_LVAL)) == VT_CONST)
vc = -vc;
else {
gv();
o(0xd8f7); /* neg %eax */
}
} else
{
vset(vat[t], vac[t]);
/* forward reference or external reference ? */
if (vt == 0) {
n = dlsym(0, idlast);
if (n == 0)
vset(VT_CONST | VT_FORWARD | VT_LVAL, vac + t);
else
vset(VT_CONST | VT_LVAL, n);
}
}
}
/* post operations */
if (tok == TOK_INC | tok == TOK_DEC) {
inc(POST_ADD, tok);
next();
} else
if (tok == '[') {
#ifndef TINY
if (!(vt & VT_PTRMASK))
error("pointer expected");
#endif
gen_op('+', -1);
/* dereference pointer */
vt = (vt - VT_PTRINC) | VT_LVAL;
skip(']');
} else
if (tok == '(') {
/* function call */
/* lvalue is implied */
vt = vt & VT_LVALN;
if ((vt & VT_CONST) == 0) {
/* evaluate function address */
gv();
o(0x50); /* push %eax */
}
ft = vt;
fc = vc;
next();
t = 0;
while (tok != ')') {
t = t + 4;
expr_eq();
gv();
o(0x50); /* push %eax */
if (tok == ',')
next();
}
skip(')');
/* horrible, but needed : convert to native ordering (could
parse parameters in reverse order, but would cost more
code) */
n = 0;
p = t - 4;
while (n < p) {
oad(0x24848b, p); /* mov x(%esp,1), %eax */
oad(0x248487, n); /* xchg x(%esp,1), %eax */
oad(0x248489, p); /* mov %eax, x(%esp,1) */
n = n + 4;
p = p - 4;
}
if (ft & VT_CONST) {
/* forward reference */
if (ft & VT_FORWARD)
*(int *)fc = psym(0xe8, *(int *)fc);
else
oad(0xe8, fc - ind - 5);
} else {
oad(0x2494ff, t); /* call *xxx(%esp) */
t = t + 4;
}
if (t)
oad(0xc481, t);
/* return value is variable, int */
vt = VT_VAR;
}
}
void uneq()
{
int ft, fc, b;
unary();
if (tok == '=') {
test_lvalue();
next();
fc = vc;
ft = vt;
b = (vt & VT_TYPE) == VT_BYTE;
if (ft & VT_VAR)
o(0x50); /* push %eax */
expr_eq();
#ifndef TINY
if ((vt & VT_PTRMASK) != (ft & VT_PTRMASK))
warning("incompatible type");
#endif
gv(); /* generate value */
if (ft & VT_VAR) {
o(0x59); /* pop %ecx */
o(0x0189 - b); /* mov %eax/%al, (%ecx) */
} else if (ft & VT_LOCAL)
oad(0x8589 - b, fc); /* mov %eax/%al,xxx(%ebp) */
else
oad(0xa3 - b, fc); /* mov %eax/%al,xxx */
}
}
void sum(l)
{
#ifndef TINY
int t;
#endif
if (l == 0)
uneq();
else {
sum(--l);
while ((l == 0 & (tok == '*' | tok == '/' | tok == '%')) |
(l == 1 & (tok == '+' | tok == '-')) |
#ifndef TINY
(l == 2 & (tok == TOK_SHL | tok == TOK_SHR)) |
#endif
(l == 3 & (tok >= TOK_LT & tok <= TOK_GT)) |
(l == 4 & (tok == TOK_EQ | tok == TOK_NE)) |
(l == 5 & tok == '&') |
(l == 6 & tok == '^') |
(l == 7 & tok == '|')) {
gen_op(tok, l);
}
}
}
#ifdef TINY
void expr()
{
sum(8);
}
#else
void eand()
{
int t;
sum(8);
t = 0;
while (1) {
if (tok != TOK_LAND) {
if (t) {
t = gtst(1, t);
vset(VT_JMP | 1, t);
}
break;
}
t = gtst(1, t);
next();
sum(8);
}
}
void eor()
{
int t, u;
eand();
t = 0;
while (1) {
if (tok != TOK_LOR) {
if (t) {
t = gtst(0, t);
vset(VT_JMP, t);
}
break;
}
t = gtst(0, t);
next();
eand();
}
}
void expr_eq()
{
int t, u;
eor();
if (tok == '?') {
next();
t = gtst(1, 0);
expr();
gv();
skip(':');
u = psym(0xe9, 0);
gsym(t);
expr_eq();
gv();
gsym(u);
}
}
void expr()
{
while (1) {
expr_eq();
if (tok != ',')
break;
next();
}
}
#endif
void block()
{
int a, c, d;
if (tok == TOK_IF) {
/* if test */
next();
skip('(');
expr();
skip(')');
a = gtst(1, 0);
block();
c = tok;
if (c == TOK_ELSE) {
next();
d = psym(0xe9, 0); /* jmp */
gsym(a);
block();
gsym(d); /* patch else jmp */
} else
gsym(a);
} else if (tok == TOK_WHILE) {
next();
d = ind;
skip('(');
expr();
skip(')');
*++lsym = gtst(1, 0);
block();
oad(0xe9, d - ind - 5); /* jmp */
gsym(*lsym--);
} else if (tok == '{') {
next();
/* declarations */
decl(VT_LOCAL);
while (tok != '}')
block();
next();
} else if (tok == TOK_RETURN) {
next();
if (tok != ';') {
expr();
gv();
}
skip(';');
rsym = psym(0xe9, rsym); /* jmp */
} else if (tok == TOK_BREAK) {
/* compute jump */
*lsym = psym(0xe9, *lsym);
next();
skip(';');
} else
#ifndef TINY
if (tok == TOK_FOR) {
int e;
next();
skip('(');
if (tok != ';')
expr();
skip(';');
d = ind;
c = ind;
a = 0;
if (tok != ';') {
expr();
a = gtst(1, 0);
}
*++lsym = a;
skip(';');
if (tok != ')') {
e = psym(0xe9, 0);
c = ind;
expr();
oad(0xe9, d - ind - 5); /* jmp */
gsym(e);
}
skip(')');
block();
oad(0xe9, c - ind - 5); /* jmp */
gsym(*lsym--);
} else
#endif
{
if (tok != ';')
expr();
skip(';');
}
}
/* 'l' is true if local declarations */
void decl(l)
{
int *a, t, b;
while (b = ist()) {
while (1) { /* iterate thru each declaration */
vt = typ(1, b);
if (tok == '{') {
/* patch forward references (XXX: does not work for
function pointers) */
if (vat[vc] == 0)
gsym(vac[vc]);
/* put function address */
vat[vc] = VT_CONST | VT_LVAL | vt;
vac[vc] = ind;
loc = 0;
o(0xe58955); /* push %ebp, mov %esp, %ebp */
a = oad(0xec81, 0); /* sub $xxx, %esp */
rsym = 0;
block();
gsym(rsym);
o(0xc3c9); /* leave, ret */
*a = loc; /* save local variables */
break;
} else {
/* variable */
vat[vc] = l | VT_LVAL | vt;
if (l == VT_LOCAL) {
loc = loc + 4;
vac[vc] = -loc;
} else {
vac[vc] = glo;
glo = glo + 4;
}
if (tok != ',') {
skip(';');
break;
}
next();
}
}
}
}
int main(int c, char **v)
{
int (*t)();
if (c < 2) {
printf("usage: tc src\n");
return 1;
}
v++;
filename = *v;
file = fopen(filename, "r");
#ifndef TINY
if (!file) {
perror(filename);
exit(1);
}
#endif
idtable = malloc(SYM_TABLE_SIZE);
#ifdef TINY
memcpy(idtable,
"int\0void\0char\0if\0else\0while\0break\0return\0define\0main", 53);
idptr = idtable + 53;
#else
memcpy(idtable,
"int\0void\0char\0if\0else\0while\0break\0return\0define\0main\0for", 57);
idptr = idtable + 57;
#endif
glo = malloc(DATA_SIZE);
prog = malloc(TEXT_SIZE);
vac = malloc(VAR_TABLE_SIZE);
vat = malloc(VAR_TABLE_SIZE);
lsym = malloc(256);
macro_stack = malloc(256);
macro_stack_ptr = macro_stack;
ind = prog;
line_num = 1;
next();
decl(VT_CONST);
#ifdef TEST
{
FILE *f;
f = fopen(v[1], "w");
fwrite((void *)prog, 1, ind - prog, f);
fclose(f);
return 0;
}
#else
t = vac[TOK_MAIN];
if (!t)
error("main() not defined");
return (*t)(c - 1, v);
#endif
}
Reference in New Issue View Git Blame Copy Permalink