diff options
Diffstat (limited to 'minic')
| -rw-r--r-- | minic/minic.y | 161 |
1 files changed, 102 insertions, 59 deletions
diff --git a/minic/minic.y b/minic/minic.y index d2e69a2..c66ac65 100644 --- a/minic/minic.y +++ b/minic/minic.y @@ -7,7 +7,8 @@ enum { NString = 16, - NVar = 256, + NGlo = 256, + NVar = 512, NStr = 256, }; @@ -58,6 +59,8 @@ struct Stmt { While, Seq, Expr, + Break, + Ret, } t; void *p1, *p2, *p3; }; @@ -66,12 +69,12 @@ int yylex(void), yyerror(char *); Symb expr(Node *), lval(Node *); FILE *of; -int lbl, tmp, nstr; -char *str[NStr]; +int lbl, tmp, nglo; +char *ini[NGlo]; struct { char v[NString]; unsigned ctyp; - char glob; + int glo; } varh[NVar]; void @@ -109,12 +112,12 @@ varclr() unsigned h; for (h=0; h<NVar; h++) - if (!varh[h].glob) + if (!varh[h].glo) varh[h].v[0] = 0; } void -varadd(char *v, int glob, unsigned ctyp) +varadd(char *v, int glo, unsigned ctyp) { unsigned h0, h; @@ -123,7 +126,7 @@ varadd(char *v, int glob, unsigned ctyp) do { if (varh[h].v[0] == 0) { strcpy(varh[h].v, v); - varh[h].glob = glob; + varh[h].glo = glo; varh[h].ctyp = ctyp; return; } @@ -133,21 +136,28 @@ varadd(char *v, int glob, unsigned ctyp) die("too many variables"); } -unsigned -varctyp(char *v, unsigned d) +Symb * +varget(char *v) { + static Symb s; unsigned h0, h; h0 = hash(v); h = h0; do { - if (strcmp(varh[h].v, v) == 0) - return varh[h].ctyp; + if (strcmp(varh[h].v, v) == 0) { + if (!varh[h].glo) { + s.t = Var; + strcpy(s.u.v, v); + } else { + s.t = Glo; + s.u.n = varh[h].glo; + } + s.ctyp = varh[h].ctyp; + return &s; + } } while (++h != h0 && varh[h].v[0] != 0); - if (d != -1u) - return d; - die("undeclared variable"); - return INT; + return 0; } char @@ -174,12 +184,12 @@ psymb(Symb s) case Var: fprintf(of, "%%%s", s.u.v); break; + case Glo: + fprintf(of, "$glo%d", s.u.n); + break; case Con: fprintf(of, "%d", s.u.n); break; - case Glo: - fprintf(of, "$%s", s.u.v); - break; } } @@ -266,9 +276,12 @@ call(Node *n, Symb *sr) unsigned ft; f = n->l->u.v; - ft = varctyp(f, FUNC(INT)); - if (KIND(ft) != FUN) - die("called variable is not a function"); + if (varget(f)) { + ft = varget(f)->ctyp; + if (KIND(ft) != FUN) + die("invalid call"); + } else + ft = FUNC(INT); sr->ctyp = DREF(ft); for (a=n->r; a; a=a->r) a->u.s = expr(a->l); @@ -329,7 +342,7 @@ expr(Node *n) case 'S': sr.t = Glo; - sprintf(sr.u.v, "str%d", n->u.n); + sr.u.n = n->u.n; sr.ctyp = IDIR(INT); break; @@ -422,9 +435,9 @@ lval(Node *n) default: die("invalid lvalue"); case 'V': - sr.t = Var; - sr.ctyp = varctyp(n->u.v, -1u); - strcpy(sr.u.v, n->u.v); + if (!varget(n->u.v)) + die("undefined variable"); + sr = *varget(n->u.v); break; case '@': sr = expr(n->l); @@ -436,23 +449,32 @@ lval(Node *n) return sr; } -void -stmt(Stmt *s) +int +stmt(Stmt *s, int b) { int l; Symb x; -Again: + if (!s) - return; + return 0; switch (s->t) { + case Ret: + x = expr(s->p1); + fprintf(of, "\tret "); + psymb(x); + fprintf(of, "\n"); + return 1; + case Break: + if (b < 0) + die("break not in loop"); + fprintf(of, "\tjmp @l%d\n", b); + return 1; case Expr: expr(s->p1); - break; + return 0; case Seq: - stmt(s->p1); - s = s->p2; - goto Again; + return stmt(s->p1, b) || stmt(s->p2, b); case If: x = expr(s->p1); fprintf(of, "\tjnz "); /* to be clean, a comparison to 0 should be inserted here */ @@ -461,15 +483,14 @@ Again: lbl += 3; fprintf(of, ", @l%d, @l%d\n", l, l+1); fprintf(of, "@l%d\n", l); - stmt(s->p2); + if (!stmt(s->p2, b)) if (s->p3) fprintf(of, "\tjmp @l%d\n", l+2); fprintf(of, "@l%d\n", l+1); - if (s->p3) { - stmt(s->p3); + if (s->p3) + if (!stmt(s->p3, b)) fprintf(of, "@l%d\n", l+2); - } - break; + return 0; case While: l = lbl; lbl += 3; @@ -479,10 +500,10 @@ Again: psymb(x); fprintf(of, ", @l%d, @l%d\n", l+1, l+2); fprintf(of, "@l%d\n", l+1); - stmt(s->p2); - fprintf(of, "\tjmp @l%d\n", l); + if (!stmt(s->p2, l+2)) + fprintf(of, "\tjmp @l%d\n", l); fprintf(of, "@l%d\n", l+2); - break; + return 0; } } @@ -547,7 +568,7 @@ mkstmt(int t, void *p1, void *p2, void *p3) %token PP MM LE GE SIZEOF %token TINT TLNG -%token IF ELSE WHILE +%token IF ELSE WHILE BREAK RETURN %right '=' %left EQ NE @@ -570,15 +591,20 @@ fdcl: type IDENT '(' ')' ';' varadd($2->u.v, 1, FUNC($1)); }; -func: prot '{' dcls stmts '}' +idcl: type IDENT ';' { - int i; + if (nglo == NGlo) + die("too many string literals"); + ini[nglo] = alloc(sizeof "{ x 0 }"); + sprintf(ini[nglo], "{ %c 0 }", irtyp($1)); + varadd($2->u.v, nglo++, $1); +}; - stmt($4); - fprintf(of, "\tret\n"); +func: prot '{' dcls stmts '}' +{ + if (!stmt($4, -1)) + fprintf(of, "\tret 0\n"); fprintf(of, "}\n\n"); - for (i=0; i<nstr; i++) - fprintf(of, "data $str%d = \"%s\"\n", i, str[i]); }; prot: IDENT '(' ')' @@ -586,7 +612,8 @@ prot: IDENT '(' ')' varclr(); lbl = 0; tmp = 0; - fprintf(of, "function $%s() {\n", $1->u.v); + varadd($1->u.v, 1, FUNC(INT)); + fprintf(of, "function w $%s() {\n", $1->u.v); fprintf(of, "@l%d\n", lbl++); }; @@ -608,6 +635,8 @@ type: type '*' { $$ = IDIR($1); } stmt: ';' { $$ = 0; } | '{' stmts '}' { $$ = $2; } + | BREAK ';' { $$ = mkstmt(Break, 0, 0, 0); } + | RETURN expr ';' { $$ = mkstmt(Ret, $2, 0, 0); } | expr ';' { $$ = mkstmt(Expr, $1, 0, 0); } | WHILE '(' expr ')' stmt { $$ = mkstmt(While, $3, $5, 0); } | IF '(' expr ')' stmt ELSE stmt { $$ = mkstmt(If, $3, $5, $7); } @@ -671,19 +700,26 @@ yylex() { "if", IF }, { "else", ELSE }, { "while", WHILE }, + { "return", RETURN }, + { "break", BREAK }, { "sizeof", SIZEOF }, { 0, 0 } }; int i, c, c1, n; char v[NString], *p; - do + do { c = getchar(); - while (isspace(c)); + if (c == '#') + while ((c = getchar()) != '\n') + ; + } while (isspace(c)); + if (c == EOF) return 0; + if (isdigit(c)) { n = 0; do { @@ -716,26 +752,28 @@ yylex() } if (c == '"') { - if (nstr == NStr) - die("too many string literals"); i = 0; n = 32; p = alloc(n); - for (i=0;; i++) { + p[0] = '"'; + for (i=1;; i++) { c = getchar(); if (c == EOF) die("unclosed string literal"); - if (c == '"' && (!i || p[i-1]!='\\')) - break; - if (i >= n) { + if (i+1 >= n) { p = memcpy(alloc(n*2), p, n); n *= 2; } p[i] = c; + if (c == '"' && (!i || p[i-1]!='\\')) + break; } - str[nstr] = p; + p[i+1] = 0; + if (nglo == NGlo) + die("too many globals"); + ini[nglo] = p; yylval.n = mknode('S', 0, 0); - yylval.n->u.n = nstr++; + yylval.n->u.n = nglo++; return STR; } @@ -765,8 +803,13 @@ yyerror(char *err) int main() { + int i; + of = stdout; + nglo = 1; if (yyparse() != 0) die("parse error"); + for (i=1; i<nglo; i++) + fprintf(of, "data $glo%d = %s\n", i, ini[i]); return 0; } |