diff options
Diffstat (limited to 'lcc/cpp/eval.c')
| -rwxr-xr-x | lcc/cpp/eval.c | 520 |
1 files changed, 520 insertions, 0 deletions
diff --git a/lcc/cpp/eval.c b/lcc/cpp/eval.c new file mode 100755 index 0000000..2442ac2 --- /dev/null +++ b/lcc/cpp/eval.c @@ -0,0 +1,520 @@ +#include <stdlib.h>
+#include <string.h>
+#include "cpp.h"
+
+#define NSTAK 32
+#define SGN 0
+#define UNS 1
+#define UND 2
+
+#define UNSMARK 0x1000
+
+struct value {
+ long val;
+ int type;
+};
+
+/* conversion types */
+#define RELAT 1
+#define ARITH 2
+#define LOGIC 3
+#define SPCL 4
+#define SHIFT 5
+#define UNARY 6
+
+/* operator priority, arity, and conversion type, indexed by tokentype */
+struct pri {
+ char pri;
+ char arity;
+ char ctype;
+} priority[] = {
+ { 0, 0, 0 }, /* END */
+ { 0, 0, 0 }, /* UNCLASS */
+ { 0, 0, 0 }, /* NAME */
+ { 0, 0, 0 }, /* NUMBER */
+ { 0, 0, 0 }, /* STRING */
+ { 0, 0, 0 }, /* CCON */
+ { 0, 0, 0 }, /* NL */
+ { 0, 0, 0 }, /* WS */
+ { 0, 0, 0 }, /* DSHARP */
+ { 11, 2, RELAT }, /* EQ */
+ { 11, 2, RELAT }, /* NEQ */
+ { 12, 2, RELAT }, /* LEQ */
+ { 12, 2, RELAT }, /* GEQ */
+ { 13, 2, SHIFT }, /* LSH */
+ { 13, 2, SHIFT }, /* RSH */
+ { 7, 2, LOGIC }, /* LAND */
+ { 6, 2, LOGIC }, /* LOR */
+ { 0, 0, 0 }, /* PPLUS */
+ { 0, 0, 0 }, /* MMINUS */
+ { 0, 0, 0 }, /* ARROW */
+ { 0, 0, 0 }, /* SBRA */
+ { 0, 0, 0 }, /* SKET */
+ { 3, 0, 0 }, /* LP */
+ { 3, 0, 0 }, /* RP */
+ { 0, 0, 0 }, /* DOT */
+ { 10, 2, ARITH }, /* AND */
+ { 15, 2, ARITH }, /* STAR */
+ { 14, 2, ARITH }, /* PLUS */
+ { 14, 2, ARITH }, /* MINUS */
+ { 16, 1, UNARY }, /* TILDE */
+ { 16, 1, UNARY }, /* NOT */
+ { 15, 2, ARITH }, /* SLASH */
+ { 15, 2, ARITH }, /* PCT */
+ { 12, 2, RELAT }, /* LT */
+ { 12, 2, RELAT }, /* GT */
+ { 9, 2, ARITH }, /* CIRC */
+ { 8, 2, ARITH }, /* OR */
+ { 5, 2, SPCL }, /* QUEST */
+ { 5, 2, SPCL }, /* COLON */
+ { 0, 0, 0 }, /* ASGN */
+ { 4, 2, 0 }, /* COMMA */
+ { 0, 0, 0 }, /* SHARP */
+ { 0, 0, 0 }, /* SEMIC */
+ { 0, 0, 0 }, /* CBRA */
+ { 0, 0, 0 }, /* CKET */
+ { 0, 0, 0 }, /* ASPLUS */
+ { 0, 0, 0 }, /* ASMINUS */
+ { 0, 0, 0 }, /* ASSTAR */
+ { 0, 0, 0 }, /* ASSLASH */
+ { 0, 0, 0 }, /* ASPCT */
+ { 0, 0, 0 }, /* ASCIRC */
+ { 0, 0, 0 }, /* ASLSH */
+ { 0, 0, 0 }, /* ASRSH */
+ { 0, 0, 0 }, /* ASOR */
+ { 0, 0, 0 }, /* ASAND */
+ { 0, 0, 0 }, /* ELLIPS */
+ { 0, 0, 0 }, /* DSHARP1 */
+ { 0, 0, 0 }, /* NAME1 */
+ { 16, 1, UNARY }, /* DEFINED */
+ { 16, 0, UNARY }, /* UMINUS */
+};
+
+int evalop(struct pri);
+struct value tokval(Token *);
+struct value vals[NSTAK], *vp;
+enum toktype ops[NSTAK], *op;
+
+/*
+ * Evaluate an #if #elif #ifdef #ifndef line. trp->tp points to the keyword.
+ */
+long
+eval(Tokenrow *trp, int kw)
+{
+ Token *tp;
+ Nlist *np;
+ int ntok, rand;
+
+ trp->tp++;
+ if (kw==KIFDEF || kw==KIFNDEF) {
+ if (trp->lp - trp->bp != 4 || trp->tp->type!=NAME) {
+ error(ERROR, "Syntax error in #ifdef/#ifndef");
+ return 0;
+ }
+ np = lookup(trp->tp, 0);
+ return (kw==KIFDEF) == (np && np->flag&(ISDEFINED|ISMAC));
+ }
+ ntok = trp->tp - trp->bp;
+ kwdefined->val = KDEFINED; /* activate special meaning of defined */
+ expandrow(trp, "<if>");
+ kwdefined->val = NAME;
+ vp = vals;
+ op = ops;
+ *op++ = END;
+ for (rand=0, tp = trp->bp+ntok; tp < trp->lp; tp++) {
+ switch(tp->type) {
+ case WS:
+ case NL:
+ continue;
+
+ /* nilary */
+ case NAME:
+ case NAME1:
+ case NUMBER:
+ case CCON:
+ case STRING:
+ if (rand)
+ goto syntax;
+ *vp++ = tokval(tp);
+ rand = 1;
+ continue;
+
+ /* unary */
+ case DEFINED:
+ case TILDE:
+ case NOT:
+ if (rand)
+ goto syntax;
+ *op++ = tp->type;
+ continue;
+
+ /* unary-binary */
+ case PLUS: case MINUS: case STAR: case AND:
+ if (rand==0) {
+ if (tp->type==MINUS)
+ *op++ = UMINUS;
+ if (tp->type==STAR || tp->type==AND) {
+ error(ERROR, "Illegal operator * or & in #if/#elsif");
+ return 0;
+ }
+ continue;
+ }
+ /* flow through */
+
+ /* plain binary */
+ case EQ: case NEQ: case LEQ: case GEQ: case LSH: case RSH:
+ case LAND: case LOR: case SLASH: case PCT:
+ case LT: case GT: case CIRC: case OR: case QUEST:
+ case COLON: case COMMA:
+ if (rand==0)
+ goto syntax;
+ if (evalop(priority[tp->type])!=0)
+ return 0;
+ *op++ = tp->type;
+ rand = 0;
+ continue;
+
+ case LP:
+ if (rand)
+ goto syntax;
+ *op++ = LP;
+ continue;
+
+ case RP:
+ if (!rand)
+ goto syntax;
+ if (evalop(priority[RP])!=0)
+ return 0;
+ if (op<=ops || op[-1]!=LP) {
+ goto syntax;
+ }
+ op--;
+ continue;
+
+ default:
+ error(ERROR,"Bad operator (%t) in #if/#elsif", tp);
+ return 0;
+ }
+ }
+ if (rand==0)
+ goto syntax;
+ if (evalop(priority[END])!=0)
+ return 0;
+ if (op!=&ops[1] || vp!=&vals[1]) {
+ error(ERROR, "Botch in #if/#elsif");
+ return 0;
+ }
+ if (vals[0].type==UND)
+ error(ERROR, "Undefined expression value");
+ return vals[0].val;
+syntax:
+ error(ERROR, "Syntax error in #if/#elsif");
+ return 0;
+}
+
+int
+evalop(struct pri pri)
+{
+ struct value v1, v2;
+ long rv1, rv2;
+ int rtype, oper;
+
+ rv2=0;
+ rtype=0;
+ while (pri.pri < priority[op[-1]].pri) {
+ oper = *--op;
+ if (priority[oper].arity==2) {
+ v2 = *--vp;
+ rv2 = v2.val;
+ }
+ v1 = *--vp;
+ rv1 = v1.val;
+/*lint -e574 -e644 */
+ switch (priority[oper].ctype) {
+ case 0:
+ default:
+ error(WARNING, "Syntax error in #if/#endif");
+ return 1;
+ case ARITH:
+ case RELAT:
+ if (v1.type==UNS || v2.type==UNS)
+ rtype = UNS;
+ else
+ rtype = SGN;
+ if (v1.type==UND || v2.type==UND)
+ rtype = UND;
+ if (priority[oper].ctype==RELAT && rtype==UNS) {
+ oper |= UNSMARK;
+ rtype = SGN;
+ }
+ break;
+ case SHIFT:
+ if (v1.type==UND || v2.type==UND)
+ rtype = UND;
+ else
+ rtype = v1.type;
+ if (rtype==UNS)
+ oper |= UNSMARK;
+ break;
+ case UNARY:
+ rtype = v1.type;
+ break;
+ case LOGIC:
+ case SPCL:
+ break;
+ }
+ switch (oper) {
+ case EQ: case EQ|UNSMARK:
+ rv1 = rv1==rv2; break;
+ case NEQ: case NEQ|UNSMARK:
+ rv1 = rv1!=rv2; break;
+ case LEQ:
+ rv1 = rv1<=rv2; break;
+ case GEQ:
+ rv1 = rv1>=rv2; break;
+ case LT:
+ rv1 = rv1<rv2; break;
+ case GT:
+ rv1 = rv1>rv2; break;
+ case LEQ|UNSMARK:
+ rv1 = (unsigned long)rv1<=rv2; break;
+ case GEQ|UNSMARK:
+ rv1 = (unsigned long)rv1>=rv2; break;
+ case LT|UNSMARK:
+ rv1 = (unsigned long)rv1<rv2; break;
+ case GT|UNSMARK:
+ rv1 = (unsigned long)rv1>rv2; break;
+ case LSH:
+ rv1 <<= rv2; break;
+ case LSH|UNSMARK:
+ rv1 = (unsigned long)rv1<<rv2; break;
+ case RSH:
+ rv1 >>= rv2; break;
+ case RSH|UNSMARK:
+ rv1 = (unsigned long)rv1>>rv2; break;
+ case LAND:
+ rtype = UND;
+ if (v1.type==UND)
+ break;
+ if (rv1!=0) {
+ if (v2.type==UND)
+ break;
+ rv1 = rv2!=0;
+ } else
+ rv1 = 0;
+ rtype = SGN;
+ break;
+ case LOR:
+ rtype = UND;
+ if (v1.type==UND)
+ break;
+ if (rv1==0) {
+ if (v2.type==UND)
+ break;
+ rv1 = rv2!=0;
+ } else
+ rv1 = 1;
+ rtype = SGN;
+ break;
+ case AND:
+ rv1 &= rv2; break;
+ case STAR:
+ rv1 *= rv2; break;
+ case PLUS:
+ rv1 += rv2; break;
+ case MINUS:
+ rv1 -= rv2; break;
+ case UMINUS:
+ if (v1.type==UND)
+ rtype = UND;
+ rv1 = -rv1; break;
+ case OR:
+ rv1 |= rv2; break;
+ case CIRC:
+ rv1 ^= rv2; break;
+ case TILDE:
+ rv1 = ~rv1; break;
+ case NOT:
+ rv1 = !rv1; if (rtype!=UND) rtype = SGN; break;
+ case SLASH:
+ if (rv2==0) {
+ rtype = UND;
+ break;
+ }
+ if (rtype==UNS)
+ rv1 /= (unsigned long)rv2;
+ else
+ rv1 /= rv2;
+ break;
+ case PCT:
+ if (rv2==0) {
+ rtype = UND;
+ break;
+ }
+ if (rtype==UNS)
+ rv1 %= (unsigned long)rv2;
+ else
+ rv1 %= rv2;
+ break;
+ case COLON:
+ if (op[-1] != QUEST)
+ error(ERROR, "Bad ?: in #if/endif");
+ else {
+ op--;
+ if ((--vp)->val==0)
+ v1 = v2;
+ rtype = v1.type;
+ rv1 = v1.val;
+ }
+ break;
+ case DEFINED:
+ break;
+ default:
+ error(ERROR, "Eval botch (unknown operator)");
+ return 1;
+ }
+/*lint +e574 +e644 */
+ v1.val = rv1;
+ v1.type = rtype;
+ *vp++ = v1;
+ }
+ return 0;
+}
+
+struct value
+tokval(Token *tp)
+{
+ struct value v;
+ Nlist *np;
+ int i, base, c;
+ unsigned long n;
+ uchar *p;
+
+ v.type = SGN;
+ v.val = 0;
+ switch (tp->type) {
+
+ case NAME:
+ v.val = 0;
+ break;
+
+ case NAME1:
+ if ((np = lookup(tp, 0)) != NULL && np->flag&(ISDEFINED|ISMAC))
+ v.val = 1;
+ break;
+
+ case NUMBER:
+ n = 0;
+ base = 10;
+ p = tp->t;
+ c = p[tp->len];
+ p[tp->len] = '\0';
+ if (*p=='0') {
+ base = 8;
+ if (p[1]=='x' || p[1]=='X') {
+ base = 16;
+ p++;
+ }
+ p++;
+ }
+ for (;; p++) {
+ if ((i = digit(*p)) < 0)
+ break;
+ if (i>=base)
+ error(WARNING,
+ "Bad digit in number %t", tp);
+ n *= base;
+ n += i;
+ }
+ if (n>=0x80000000 && base!=10)
+ v.type = UNS;
+ for (; *p; p++) {
+ if (*p=='u' || *p=='U')
+ v.type = UNS;
+ else if (*p=='l' || *p=='L')
+ ;
+ else {
+ error(ERROR,
+ "Bad number %t in #if/#elsif", tp);
+ break;
+ }
+ }
+ v.val = n;
+ tp->t[tp->len] = c;
+ break;
+
+ case CCON:
+ n = 0;
+ p = tp->t;
+ if (*p=='L') {
+ p += 1;
+ error(WARNING, "Wide char constant value undefined");
+ }
+ p += 1;
+ if (*p=='\\') {
+ p += 1;
+ if ((i = digit(*p))>=0 && i<=7) {
+ n = i;
+ p += 1;
+ if ((i = digit(*p))>=0 && i<=7) {
+ p += 1;
+ n <<= 3;
+ n += i;
+ if ((i = digit(*p))>=0 && i<=7) {
+ p += 1;
+ n <<= 3;
+ n += i;
+ }
+ }
+ } else if (*p=='x') {
+ p += 1;
+ while ((i = digit(*p))>=0 && i<=15) {
+ p += 1;
+ n <<= 4;
+ n += i;
+ }
+ } else {
+ static char cvcon[]
+ = "b\bf\fn\nr\rt\tv\v''\"\"??\\\\";
+ for (i=0; i<sizeof(cvcon); i+=2) {
+ if (*p == cvcon[i]) {
+ n = cvcon[i+1];
+ break;
+ }
+ }
+ p += 1;
+ if (i>=sizeof(cvcon))
+ error(WARNING,
+ "Undefined escape in character constant");
+ }
+ } else if (*p=='\'')
+ error(ERROR, "Empty character constant");
+ else
+ n = *p++;
+ if (*p!='\'')
+ error(WARNING, "Multibyte character constant undefined");
+ else if (n>127)
+ error(WARNING, "Character constant taken as not signed");
+ v.val = n;
+ break;
+
+ case STRING:
+ error(ERROR, "String in #if/#elsif");
+ break;
+ }
+ return v;
+}
+
+int
+digit(int i)
+{
+ if ('0'<=i && i<='9')
+ i -= '0';
+ else if ('a'<=i && i<='f')
+ i -= 'a'-10;
+ else if ('A'<=i && i<='F')
+ i -= 'A'-10;
+ else
+ i = -1;
+ return i;
+}
|