1423 lines
22 KiB
C
1423 lines
22 KiB
C
#include "b.h"
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void extdef(void);
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struct hshtab * lookup(void);
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void blkhed(void);
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void blkend(void);
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void statement(int d);
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struct tnode * tree(void);
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void errflush(int o);
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int line = 1;
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int peeksym = -1, peeksym2 = -1;;
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int contlab = -1;
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int brklab = -1;
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int wordsize = 4;
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const char* modulename = "bmodule_main";
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int bsymb_part;
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int code_part;
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int string_part;
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int paramsize;
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struct hshtab hshtab[HSHSIZ];
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int hshused;
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int eof;
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int peekc;
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const char* ctab;
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struct hshtab *bsym;
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struct hshtab *paraml, *parame;
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int cval;
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int isn;
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char symbuf[NCPS+1];
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FILE *sbufp;
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int stack;
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struct tnode **cp;
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int *space;
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int ospace[OSSIZ];
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int retlab;
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int nerror;
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struct swtab swtab[SWSIZ];
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struct swtab *swp;
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int deflab;
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int contlab;
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int brklab;
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int opdope[];
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int line;
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int peeksym, peeksym2;
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void
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init(char *s, int val)
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{
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char *sp;
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struct hshtab *np;
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sp = symbuf;
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while (sp < symbuf+NCPS+1)
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if ((*sp++ = *s++) == '\0')
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s--;
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np = lookup();
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np->class = KEYWF;
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np->offset = val;
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}
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static void
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usage(void)
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{
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error("Usage: em_b [-w wordsize] [-B modulename] [-i inputfile] [-o outputfile]");
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exit(1);
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}
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int
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main(int argc, char *argv[])
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{
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for (;;) {
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int opt = getopt(argc, argv, "w:B:i:o:");
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if (opt == -1)
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break;
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switch (opt) {
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case 'w':
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wordsize = atoi(optarg);
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break;
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case 'B':
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modulename = aprintf("bmodule_%s", optarg);
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break;
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case 'i':
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if (freopen(optarg, "r", stdin) == NULL) {
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error("Can't find %s", optarg);
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exit(1);
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}
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break;
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case 'o':
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if (freopen(optarg, "w", stdout) == NULL) {
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error("Can't create %s", optarg);
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exit(1);
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}
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break;
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default:
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usage();
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}
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}
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if (optind < argc)
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usage();
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init("auto", AUTO);
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init("extrn", EXTERN);
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init("case", CASE);
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init("if", IF);
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init("else", ELSE);
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init("while", WHILE);
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init("switch", SWITCH);
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init("goto", GOTO);
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init("return", RETURN);
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init("default", DEFAULT);
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init("break", BREAK);
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C_init(wordsize, wordsize);
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C_open(NULL);
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C_magic();
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C_ms_emx(wordsize, wordsize);
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bsymb_part = 0;
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string_part = 0;
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code_part = C_getid();
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C_beginpart(code_part);
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while (!eof) {
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extdef();
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blkend();
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}
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C_endpart(code_part);
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C_insertpart(code_part);
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if (string_part)
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C_insertpart(string_part);
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C_exa_dnam((char*) modulename);
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C_df_dnam((char*) modulename);
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if (bsymb_part)
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C_insertpart(bsymb_part);
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C_rom_cst(0);
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C_close();
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return nerror != 0;
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}
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/*
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* Lexer
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*/
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int
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spnextchar(void)
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{
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int c;
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if ((c = peekc) == 0)
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c = getchar();
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if (c == '\t')
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c = ' ';
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else if (c == '\n') {
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c = ' ';
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line++;
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}
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peekc = c;
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return c;
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}
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int
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nextchar(void)
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{
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while (spnextchar() == ' ')
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peekc = 0;
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return peekc;
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}
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int
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subseq(int c, int a, int b)
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{
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if (spnextchar() != c)
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return a;
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peekc = 0;
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return b;
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}
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/* Only decimal and octal bases, could extend */
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int
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getnum(void)
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{
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int base;
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int c;
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base = 10;
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cval = 0;
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if ((c=spnextchar()) == '0')
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base = 8;
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for (; ctab[c] == DIGIT; c = getchar())
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cval = cval*base + c-'0';
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peekc = c;
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return CON;
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}
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int
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mapch(char c)
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{
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int a;
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if ((a=getchar()) == c)
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return -1;
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switch (a) {
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case '\n':
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case '\0':
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error("Nonterminated string");
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peekc = a;
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return -1;
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case '*':
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switch (a=getchar()) {
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case 't':
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return('\t');
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case 'n':
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return('\n');
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case '0':
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return('\0');
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case '(':
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return('{');
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case ')':
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return('}');
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case 'e':
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return(EOS);
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case '\n':
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line++;
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return('\n');
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}
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}
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return a;
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}
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int
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getcc(void)
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{
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char *cp;
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int c, cc;
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cval = 0;
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cc = 0;
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cp = (char*) &cval;
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while ((c = mapch('\'')) >= 0)
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if (cc++ < wordsize)
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*cp++ = c;
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if (cc > wordsize)
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error("Long character constant");
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return CON;
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}
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int
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getstr(void)
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{
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int c;
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int i;
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char b;
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int partid;
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partid = C_getid();
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C_beginpart(partid);
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if (string_part)
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C_insertpart(string_part);
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cval = isn++;
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C_df_dlb(cval);
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for (i = 1; (c = mapch('"')) >= 0; i++) {
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b = c;
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C_con_scon(&b, 1);
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}
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b = 04;
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C_con_scon(&b, 1);
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b = 0;
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while ((i++%4) != 0)
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C_con_scon(&b, 1);
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C_endpart(partid);
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string_part = partid;
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return STRING;
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}
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struct hshtab *
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lookup(void)
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{
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int i;
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char *sp, *np;
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struct hshtab *rp;
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i = 0;
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sp = symbuf;
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while (sp < symbuf+NCPS)
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i += *sp++&0177;
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rp = &hshtab[i%HSHSIZ];
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while (*(np = rp->name)) {
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for (sp=symbuf; sp < symbuf+NCPS;)
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if (*np++ != *sp++)
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goto no;
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return rp;
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no:
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if (++rp >= &hshtab[HSHSIZ])
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rp = hshtab;
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}
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if (++hshused > HSHSIZ) {
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error("Symbol table overflow");
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exit(1);
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}
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rp->class = 0;
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rp->offset = 0;
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rp->dim = 0;
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sp = symbuf;
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for (np = rp->name; sp < symbuf+NCPS+1;)
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*np++ = *sp++;
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return rp;
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}
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/*
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* Symbol peeking with one peeksym doesn't work if an ASSIGN is only peeked,
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* since it itself peeks a symbol, which is then overwritten.
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*/
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/* Note: does not push bsyms !! */
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int
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pushsym(int sym)
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{
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if (peeksym < 0)
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peeksym = sym;
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else if (peeksym2 < 0) {
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peeksym2 = peeksym;
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peeksym = sym;
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} else
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error("Cannot push more than two symbols\n");
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return sym;
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}
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int
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symbol(void)
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{
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int c;
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char *sp;
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if (peeksym >= 0) {
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c = peeksym;
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peeksym = peeksym2;
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peeksym2 = -1;
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return c;
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}
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if (peekc) {
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c = peekc;
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peekc = 0;
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} else
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if (eof)
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return EOFC;
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else
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c = getchar();
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if (c==EOF) {
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eof++;
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return(EOFC);
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}
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loop:
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switch (ctab[c]) {
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case NEWLN:
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line++;
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/* fall through */
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case SPACE:
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c = getchar();
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goto loop;
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case HASH:
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/* # is invalid in B; but we handle it out of convenience so that we can read
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* in input files that have been run through the C preprocessor. Ideally we
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* should only recognise it when it's the first character in a line, but as
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* it's not used anywhere else we can get away with recognising it anywhere.
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*/
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while ((c = getchar()) == ' ')
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;
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peekc = c;
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getnum();
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line = cval;
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while ((c = getchar()) != '\n')
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;
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goto loop;
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case PLUS:
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return subseq(c,PLUS,INCBEF);
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case MINUS:
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return subseq(c,MINUS,DECBEF);
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case LESS:
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if (subseq(c,0,1))
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return LSHIFT;
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return subseq('=', LESS, LESSEQ);
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|
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case GREAT:
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if (subseq(c,0,1))
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return RSHIFT;
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return subseq('=', GREAT, GREATEQ);
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|
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case ASSIGN:
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if (subseq(' ',0,1))
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return ASSIGN;
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/* avoid peeking a name, which could overwrite
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* an already set bsym. */
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if (ctab[peekc = spnextchar()] == LETTER)
|
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return ASSIGN;
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c = symbol();
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if (PLUS <= c && c <= EOR)
|
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return c + ASPLUS-PLUS;
|
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if (c == ASSIGN)
|
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return EQUAL;
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pushsym(c);
|
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return ASSIGN;
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|
|
case EXCLA:
|
|
return subseq('=',EXCLA,NEQUAL);
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|
|
|
case DIVIDE:
|
|
if (subseq('*',1,0))
|
|
return DIVIDE;
|
|
while ((c = spnextchar()) != EOFC) {
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peekc = 0;
|
|
if (c == '*') {
|
|
if (spnextchar() == '/') {
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peekc = 0;
|
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c = getchar();
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goto loop;
|
|
}
|
|
}
|
|
}
|
|
eof++;
|
|
error("Nonterminated comment");
|
|
return EOFC;
|
|
|
|
case DIGIT:
|
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peekc = c;
|
|
return getnum();
|
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|
|
case SQUOTE:
|
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return(getcc());
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|
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case DQUOTE:
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|
return(getstr());
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|
|
case LETTER:
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|
sp = symbuf;
|
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while (ctab[c] == LETTER || ctab[c] == DIGIT) {
|
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if (sp < symbuf+NCPS)
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*sp++ = c;
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c = getchar();
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}
|
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while (sp < symbuf+NCPS+1)
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*sp++ = '\0';
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peekc = c;
|
|
bsym = lookup();
|
|
if (bsym->class == KEYWF) {
|
|
cval = bsym->offset;
|
|
return KEYW;
|
|
}
|
|
return NAME;
|
|
|
|
case UNKN:
|
|
error("Unknown character");
|
|
c = getchar();
|
|
goto loop;
|
|
}
|
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return (ctab[c]);
|
|
}
|
|
|
|
/*
|
|
* Declarations and Definitions
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*/
|
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|
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/* Declares a list of names to be of storage class "kw". */
|
|
void
|
|
declare(int kw)
|
|
{
|
|
int o;
|
|
|
|
while ((o = symbol()) == NAME) {
|
|
if (bsym->class)
|
|
error("%s redeclared", bsym->name);
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|
bsym->class = kw;
|
|
while ((o = symbol()) == LBRACK) {
|
|
if ((o = symbol()) == CON) {
|
|
if (bsym->dim)
|
|
error("Bad vector");
|
|
bsym->dim = cval + 1;
|
|
o = symbol();
|
|
}
|
|
if (o != RBRACK)
|
|
goto syntax;
|
|
}
|
|
if (kw == ARG) {
|
|
bsym->next = NULL;
|
|
if (!paraml)
|
|
paraml = bsym;
|
|
else
|
|
parame->next = bsym;
|
|
parame = bsym;
|
|
}
|
|
if (o != COMMA)
|
|
break;
|
|
}
|
|
if ((o == SEMI && kw != ARG) || (o == RPARN && kw == ARG))
|
|
return;
|
|
syntax:
|
|
error("Declaration syntax");
|
|
errflush(o);
|
|
}
|
|
|
|
void
|
|
declist(void)
|
|
{
|
|
int o;
|
|
|
|
while ((o = symbol()) == KEYW && (cval == AUTO || cval == EXTERN))
|
|
declare(cval);
|
|
pushsym(o);
|
|
}
|
|
|
|
void
|
|
function(void)
|
|
{
|
|
declare(ARG);
|
|
statement(1);
|
|
C_ret(0);
|
|
C_end(paramsize);
|
|
}
|
|
|
|
void
|
|
global(char *s)
|
|
{
|
|
C_exa_dnam(manglename(s, 'b'));
|
|
}
|
|
|
|
void
|
|
bsymb(char *s)
|
|
{
|
|
int newpart = C_getid();
|
|
C_beginpart(newpart);
|
|
if (bsymb_part != 0)
|
|
C_insertpart(bsymb_part);
|
|
C_rom_dlb(isn, 0);
|
|
C_endpart(newpart);
|
|
|
|
bsymb_part = newpart;
|
|
C_df_dlb(isn++);
|
|
}
|
|
|
|
void
|
|
extdef(void)
|
|
{
|
|
int o, dim, i;
|
|
char *bs;
|
|
char *ms;
|
|
int neg;
|
|
|
|
if ((o = symbol()) == EOFC || o == SEMI)
|
|
return;
|
|
if (o != NAME)
|
|
goto syntax;
|
|
bs = bsym->name;
|
|
i = dim = 0;
|
|
neg = 0;
|
|
switch(o = symbol()) {
|
|
|
|
case SEMI:
|
|
global(bs);
|
|
C_df_dnam(manglename(bs, 'b'));
|
|
C_bss_cst(wordsize, 0, 1);
|
|
goto done;
|
|
|
|
/* init */
|
|
case CON:
|
|
case STRING:
|
|
case MINUS:
|
|
global(bs);
|
|
if (o == STRING)
|
|
bsymb(bs);
|
|
else if (o == MINUS) {
|
|
o = symbol();
|
|
if (o != CON)
|
|
goto syntax;
|
|
cval = -cval;
|
|
}
|
|
C_df_dnam(manglename(bs, 'b'));
|
|
pushsym(o);
|
|
goto init;
|
|
|
|
/* vector */
|
|
case LBRACK:
|
|
if ((o=symbol()) == CON) {
|
|
dim = cval + 1;
|
|
o=symbol();
|
|
}
|
|
if (o != RBRACK)
|
|
goto syntax;
|
|
global(bs);
|
|
if ((o=symbol()) == SEMI) {
|
|
bsymb(bs);
|
|
C_df_dnam(manglename(bs, 'b'));
|
|
C_con_dlb(isn, 0);
|
|
C_df_dlb(isn++);
|
|
C_bss_cst(wordsize*dim, 0, 1);
|
|
goto done;
|
|
}
|
|
bsymb(bs);
|
|
C_df_dnam(manglename(bs, 'b'));
|
|
C_con_dlb(isn, 0);
|
|
C_df_dlb(isn++);
|
|
pushsym(o);
|
|
|
|
init:
|
|
do {
|
|
if ((o=symbol()) != CON && o != STRING && o != NAME)
|
|
goto syntax;
|
|
if (o == NAME) {
|
|
bsymb(NULL);
|
|
C_con_dnam(manglename(bsym->name, 'b'), 0);
|
|
} else {
|
|
if (o == STRING) {
|
|
bsymb(NULL);
|
|
C_con_dlb(cval, 0);
|
|
} else
|
|
C_con_cst(cval);
|
|
}
|
|
i++;
|
|
} while ((o=symbol()) == COMMA);
|
|
dim = (i > dim) ? i : dim;
|
|
if (i == 0)
|
|
C_bss_cst((dim-i)*wordsize, 0, 1);
|
|
else {
|
|
while (dim -i) {
|
|
C_con_cst(0);
|
|
i++;
|
|
}
|
|
}
|
|
if (o == SEMI)
|
|
goto done;
|
|
goto syntax;
|
|
|
|
/* function */
|
|
case LPARN:
|
|
global(bs);
|
|
ms = manglename(bs, 'b');
|
|
bsymb(ms);
|
|
C_df_dnam(ms);
|
|
ms = manglename(bs, 'i');
|
|
C_con_pnam(ms);
|
|
C_inp(ms);
|
|
C_pro_narg(ms);
|
|
function();
|
|
done:
|
|
return;
|
|
|
|
case EOFC:
|
|
return;
|
|
}
|
|
syntax:
|
|
error("External definition syntax");
|
|
printtoken(o, stderr);
|
|
errflush(o);
|
|
statement(0);
|
|
}
|
|
|
|
void
|
|
blkhed(void)
|
|
{
|
|
int al, pl;
|
|
struct hshtab *bs;
|
|
|
|
declist();
|
|
stack = al = -wordsize;
|
|
pl = 0; /* EM parameters start at offset 0. */
|
|
while (paraml) {
|
|
paraml = (bs = paraml)->next;
|
|
bs->offset = pl;
|
|
pl += wordsize;
|
|
}
|
|
for (bs = hshtab; bs < &hshtab[HSHSIZ]; bs++)
|
|
if (bs->name[0]) {
|
|
if (bs->class == AUTO) {
|
|
bs->offset = al;
|
|
if (bs->dim) {
|
|
al -= bs->dim*wordsize;
|
|
C_lal(al);
|
|
al -= wordsize;
|
|
fromnativeaddr();
|
|
C_stl(al);
|
|
bs->offset = al;
|
|
}
|
|
al -= wordsize;
|
|
} else if (bs->class == ARG)
|
|
bs->class = AUTO;
|
|
}
|
|
paramsize = -al - wordsize;
|
|
}
|
|
|
|
void
|
|
blkend(void)
|
|
{
|
|
struct hshtab *np;
|
|
|
|
for (np = hshtab; np < &hshtab[HSHSIZ]; np++)
|
|
if (np->class != KEYWF) {
|
|
np->name[0] = '\0';
|
|
hshused--;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Statements and Expressions
|
|
*/
|
|
|
|
struct tnode *
|
|
pexpr(void)
|
|
{
|
|
struct tnode *t;
|
|
int o;
|
|
|
|
if ((o = symbol()) != LPARN)
|
|
goto syntax;
|
|
t = tree();
|
|
if ((o = symbol()) != RPARN)
|
|
goto syntax;
|
|
return t;
|
|
syntax:
|
|
error("Statement syntax");
|
|
errflush(o);
|
|
return NULL;
|
|
}
|
|
|
|
void
|
|
fnlabel(int l)
|
|
{
|
|
C_ilb(l);
|
|
}
|
|
|
|
/* Jump to "lab", if the expression "t" evaluated to 0. */
|
|
void
|
|
cbranch(struct tnode *t, int lab)
|
|
{
|
|
rcexpr(t);
|
|
C_zeq(lab);
|
|
}
|
|
|
|
void
|
|
jump(int lab)
|
|
{
|
|
C_bra(lab);
|
|
}
|
|
|
|
void
|
|
pswitch(void)
|
|
{
|
|
struct swtab *sswp;
|
|
int dl, swlab;
|
|
|
|
if (swp == NULL)
|
|
swp = swtab;
|
|
sswp = swp;
|
|
swlab = isn++;
|
|
C_lae_dlb(swlab, 0);
|
|
C_csb(wordsize);
|
|
|
|
dl = deflab;
|
|
deflab = 0;
|
|
statement(0);
|
|
if (!deflab)
|
|
deflab = brklab;
|
|
|
|
C_df_dlb(swlab);
|
|
C_rom_ilb(deflab);
|
|
C_rom_cst(swp - sswp);
|
|
|
|
while (swp > sswp && swp > swtab) {
|
|
--swp;
|
|
C_rom_cst(swp->swval);
|
|
C_rom_ilb(swp->swlab);
|
|
}
|
|
|
|
C_df_ilb(brklab);
|
|
|
|
deflab = dl;
|
|
swp = sswp;
|
|
}
|
|
|
|
void
|
|
statement(int d)
|
|
{
|
|
int o, o1, o2;
|
|
|
|
stmt:
|
|
if ((o = symbol()) == LBRACE) {
|
|
if (d)
|
|
blkhed();
|
|
while (!eof) {
|
|
if ((o = symbol()) == RBRACE)
|
|
goto bend;
|
|
pushsym(o);
|
|
statement(0);
|
|
}
|
|
error("Missing '}'");
|
|
bend:
|
|
return;
|
|
} else {
|
|
pushsym(o);
|
|
if (d)
|
|
blkhed();
|
|
}
|
|
|
|
switch (o = symbol()) {
|
|
|
|
case EOFC:
|
|
error("Unexpected EOF");
|
|
|
|
case SEMI:
|
|
case RBRACE:
|
|
return;
|
|
|
|
case KEYW:
|
|
switch (cval) {
|
|
case GOTO:
|
|
if ((o = symbol()) != NAME)
|
|
goto syntax;
|
|
if (bsym->offset == 0)
|
|
bsym->offset = isn++;
|
|
jump(bsym->offset);
|
|
goto semi;
|
|
|
|
case RETURN:
|
|
if (pushsym(symbol()) == LPARN) {
|
|
rcexpr(pexpr());
|
|
C_ret(wordsize);
|
|
} else {
|
|
C_ret(0);
|
|
}
|
|
goto semi;
|
|
|
|
case IF:
|
|
cbranch(pexpr(), o1=isn++);
|
|
statement(0);
|
|
if ((o = symbol()) == KEYW && cval == ELSE) {
|
|
jump(o2 = isn++);
|
|
fnlabel(o1);
|
|
statement(0);
|
|
fnlabel(o2);
|
|
return;
|
|
}
|
|
pushsym(o);
|
|
fnlabel(o1);
|
|
return;
|
|
|
|
case WHILE:
|
|
o1 = contlab;
|
|
o2 = brklab;
|
|
fnlabel(contlab = isn++);
|
|
cbranch(pexpr(), brklab=isn++);
|
|
statement(0);
|
|
jump(contlab);
|
|
fnlabel(brklab);
|
|
contlab = o1;
|
|
brklab = o2;
|
|
return;
|
|
|
|
case BREAK:
|
|
if (brklab < 0)
|
|
error("Nothing to break from");
|
|
jump(brklab);
|
|
goto semi;
|
|
|
|
/* Not part of B, but very easy to implement */
|
|
/*
|
|
case CONTINUE:
|
|
if (contlab < 0)
|
|
error("Nothing to continue");
|
|
jump(contlab);
|
|
goto semi;
|
|
*/
|
|
|
|
case SWITCH:
|
|
o1 = brklab;
|
|
brklab = isn++;
|
|
rcexpr(pexpr());
|
|
/* rcexpr(tree()); */
|
|
pswitch();
|
|
brklab = o1;
|
|
return;
|
|
|
|
case CASE:
|
|
if ((o = symbol()) != CON)
|
|
goto syntax;
|
|
if ((o = symbol()) != COLON)
|
|
goto syntax;
|
|
if (swp == NULL) {
|
|
error("Case not in switch");
|
|
goto stmt;
|
|
}
|
|
if (swp >= swtab+SWSIZ)
|
|
error("Switch table overflow");
|
|
else {
|
|
swp->swlab = isn;
|
|
(swp++)->swval = cval;
|
|
fnlabel(isn++);
|
|
}
|
|
goto stmt;
|
|
|
|
case DEFAULT:
|
|
if (swp == NULL)
|
|
error("Default not in switch");
|
|
if ((o = symbol()) != COLON)
|
|
goto syntax;
|
|
deflab = isn++;
|
|
fnlabel(deflab);
|
|
goto stmt;
|
|
}
|
|
|
|
error("Unknown keyword");
|
|
goto syntax;
|
|
|
|
case NAME:
|
|
if (peekc == ':') {
|
|
peekc = 0;
|
|
if (bsym->class) {
|
|
error("Redefinition");
|
|
goto stmt;
|
|
}
|
|
bsym->class = INTERN;
|
|
if (bsym->offset == 0)
|
|
bsym->offset = isn++;
|
|
fnlabel(bsym->offset);
|
|
goto stmt;
|
|
}
|
|
}
|
|
pushsym(o);
|
|
rcexpr(tree());
|
|
C_asp(wordsize);
|
|
goto semi;
|
|
|
|
semi:
|
|
if ((o = symbol()) != SEMI)
|
|
goto syntax;
|
|
return;
|
|
|
|
syntax:
|
|
error("Statement syntax");
|
|
errflush(o);
|
|
goto stmt;
|
|
}
|
|
|
|
struct tnode *
|
|
block(int op, int value, struct tnode *tr1, struct tnode *tr2)
|
|
{
|
|
struct tnode t;
|
|
int n;
|
|
int *p, *ap;
|
|
|
|
p = space;
|
|
t.op = op;
|
|
t.value = value;
|
|
t.tr1 = tr1;
|
|
t.tr2 = tr2;
|
|
ap = (int*) &t;
|
|
n = (sizeof(struct tnode)+sizeof(int)-1) & ~sizeof(int);
|
|
if (space+n >= &ospace[OSSIZ]) {
|
|
error("Expression overflow 1");
|
|
exit(1);
|
|
}
|
|
while (n--)
|
|
*space++ = *ap++;
|
|
return (struct tnode *) p;
|
|
}
|
|
|
|
void
|
|
chklval(struct tnode *p)
|
|
{
|
|
if (p->op != NAME && p->op != STAR)
|
|
error("Lvalue required");
|
|
}
|
|
|
|
void
|
|
build(int op)
|
|
{
|
|
struct tnode *p1, *p2;
|
|
int dope;
|
|
|
|
/* a[i] -> *(a+i) */
|
|
if (op == LBRACK) {
|
|
build(PLUS);
|
|
op = STAR;
|
|
}
|
|
dope = opdope[op];
|
|
if (dope&01)
|
|
p2 = *--cp;
|
|
p1 = *--cp;
|
|
switch (op) {
|
|
case QUEST:
|
|
if (p2->op != COLON)
|
|
error("Illegal conditional");
|
|
break;
|
|
|
|
case AMPER:
|
|
if (p1->op == STAR) {
|
|
*cp++ = p1->tr1;
|
|
return;
|
|
}
|
|
if (p1->op == NAME) {
|
|
*cp++ = block(op,0,p1,NULL);
|
|
return;
|
|
}
|
|
error("Illegal lvalue");
|
|
}
|
|
if (dope&02)
|
|
chklval(p1);
|
|
if (dope&01)
|
|
*cp++ = block(op,0,p1,p2);
|
|
else
|
|
*cp++ = block(op,0,p1,NULL);
|
|
}
|
|
|
|
struct tnode *
|
|
tree(void)
|
|
{
|
|
struct tnode *cmst[CMSIZ];
|
|
int opst[SSIZE], prst[SSIZE];
|
|
int *op, *pp;
|
|
int andflg;
|
|
int o, os;
|
|
int p, ps;
|
|
|
|
space = ospace;
|
|
op = opst;
|
|
pp = prst;
|
|
cp = cmst;
|
|
*op = SEOF;
|
|
*pp = 06;
|
|
andflg = 0;
|
|
|
|
advanc:
|
|
switch (o=symbol()) {
|
|
case NAME:
|
|
if (pushsym(symbol()) == LPARN) { /* function */
|
|
if (bsym->class == 0)
|
|
bsym->class = EXTERN;
|
|
} else if (bsym->class == 0) {
|
|
error("%s undefined", bsym->name);
|
|
bsym->class = EXTERN;
|
|
}
|
|
*cp++ = block(NAME,0,(struct tnode *)bsym,NULL);
|
|
goto tand;
|
|
|
|
case STRING:
|
|
*cp++ = block(STRING,cval,NULL,NULL);
|
|
goto tand;
|
|
|
|
case CON:
|
|
caseCON:
|
|
*cp++ = block(CON,cval,NULL,NULL);
|
|
goto tand;
|
|
|
|
tand:
|
|
if (cp >= &cmst[CMSIZ]) {
|
|
error("Expression overflow 2");
|
|
exit(1);
|
|
}
|
|
if (andflg)
|
|
goto syntax;
|
|
andflg = 1;
|
|
goto advanc;
|
|
|
|
case DECBEF:
|
|
case INCBEF:
|
|
if (andflg)
|
|
o += 2;
|
|
goto oponst;
|
|
|
|
case EXCLA:
|
|
case NOT:
|
|
if (andflg)
|
|
goto syntax;
|
|
goto oponst;
|
|
|
|
case MINUS:
|
|
if (!andflg) {
|
|
if (pushsym(symbol()) == CON) {
|
|
symbol();
|
|
cval = -cval;
|
|
goto caseCON;
|
|
}
|
|
o = NEG;
|
|
}
|
|
andflg = 0;
|
|
goto oponst;
|
|
|
|
case AND:
|
|
case TIMES:
|
|
if (andflg)
|
|
andflg = 0;
|
|
else
|
|
if (o == AND)
|
|
o = AMPER;
|
|
else
|
|
o = STAR;
|
|
goto oponst;
|
|
|
|
case LPARN:
|
|
if (andflg) {
|
|
o = symbol();
|
|
if (o == RPARN)
|
|
o = MCALL;
|
|
else {
|
|
pushsym(o);
|
|
o = CALL;
|
|
andflg = 0;
|
|
}
|
|
}
|
|
goto oponst;
|
|
|
|
case RPARN:
|
|
case RBRACK:
|
|
if (!andflg)
|
|
goto syntax;
|
|
goto oponst;
|
|
}
|
|
|
|
if (!andflg)
|
|
goto syntax;
|
|
andflg = 0;
|
|
|
|
oponst:
|
|
p = (opdope[o]>>9) & 077;
|
|
opon1:
|
|
ps = *pp;
|
|
if (p > ps || (p == ps && (opdope[o]&0200))) { /* right-assoc */
|
|
switch (o) {
|
|
case LPARN:
|
|
case LBRACK:
|
|
case CALL:
|
|
p = 04;
|
|
}
|
|
if (op >= &opst[SSIZE]) {
|
|
error("Expression overflow 3");
|
|
exit(1);
|
|
}
|
|
*++op = o;
|
|
*++pp = p;
|
|
goto advanc;
|
|
}
|
|
--pp;
|
|
switch (os = *op--) {
|
|
case SEOF:
|
|
pushsym(o);
|
|
return(*--cp);
|
|
|
|
case CALL:
|
|
if (o != RPARN)
|
|
goto syntax;
|
|
build(os);
|
|
goto advanc;
|
|
|
|
case MCALL:
|
|
*cp++ = NULL;
|
|
os = CALL;
|
|
goto fbuild;
|
|
|
|
case LPARN:
|
|
if (o != RPARN)
|
|
goto syntax;
|
|
goto advanc;
|
|
|
|
case LBRACK:
|
|
if (o != RBRACK)
|
|
goto syntax;
|
|
build(LBRACK);
|
|
goto advanc;
|
|
|
|
}
|
|
fbuild:
|
|
build(os);
|
|
goto opon1;
|
|
syntax:
|
|
error("Expression syntax");
|
|
errflush(o);
|
|
return NULL;
|
|
}
|
|
|
|
void
|
|
error(char *s, ...)
|
|
{
|
|
va_list args;
|
|
|
|
va_start(args, s);
|
|
nerror++;
|
|
fprintf(stderr, "%d: ", line);
|
|
vfprintf(stderr, s, args);
|
|
putc('\n', stderr);
|
|
va_end(args);
|
|
}
|
|
|
|
void
|
|
errflush(int o)
|
|
{
|
|
while (o > RBRACE) /* ; { } */
|
|
o = symbol();
|
|
pushsym(o);
|
|
}
|
|
|
|
/*
|
|
* 000001 binary
|
|
* 000002 need lvalue
|
|
* 000004 relational
|
|
* 000010 assignment
|
|
* 000100 commutative
|
|
* 000200 right-assoc
|
|
* 0XX000 precedence
|
|
*/
|
|
int opdope[] = {
|
|
000000, /* EOFC */
|
|
000000, /* ; */
|
|
000000, /* { */
|
|
000000, /* } */
|
|
036000, /* [ */
|
|
002000, /* ] */
|
|
036000, /* ( */
|
|
002000, /* ) */
|
|
014201, /* : */
|
|
007001, /* , */
|
|
000000, /* 10 */
|
|
000000, /* 11 */
|
|
000000, /* 12 */
|
|
000000, /* 13 */
|
|
000000, /* 14 */
|
|
036001, /* mcall */
|
|
036001, /* call */
|
|
034202, /* ++a */
|
|
034202, /* a++ */
|
|
034202, /* --a */
|
|
034202, /* a-- */
|
|
034200, /* !un */
|
|
034200, /* -un */
|
|
034200, /* &un */
|
|
034200, /* *un */
|
|
014201, /* ? */
|
|
034200, /* ~un */
|
|
000000, /* 27 */
|
|
000000, /* 28 */
|
|
000000, /* 29 */
|
|
030101, /* + */
|
|
030001, /* - */
|
|
032001, /* % */
|
|
032101, /* * */
|
|
032001, /* / */
|
|
016101, /* | */
|
|
020101, /* & */
|
|
026001, /* << */
|
|
026001, /* >> */
|
|
022105, /* == */
|
|
022105, /* != */
|
|
024005, /* <= */
|
|
024005, /* < */
|
|
024005, /* >= */
|
|
024005, /* > */
|
|
017005, /* ^ */
|
|
000000, /* 46 */
|
|
000000, /* 47 */
|
|
000000, /* 48 */
|
|
012013, /* = */
|
|
012213, /* =+ */
|
|
012213, /* =- */
|
|
012213, /* =% */
|
|
012213, /* =* */
|
|
012213, /* =/ */
|
|
012213, /* =| */
|
|
012213, /* =& */
|
|
012213, /* =<< */
|
|
012213, /* =>> */
|
|
012213, /* === */
|
|
012213, /* =!= */
|
|
012213, /* =<= */
|
|
012213, /* =< */
|
|
012213, /* =>= */
|
|
012213, /* => */
|
|
012213, /* =^ */
|
|
000000, /* 66 */
|
|
000000, /* 67 */
|
|
000000, /* 68 */
|
|
000000, /* 69 */
|
|
000000, /* CON */
|
|
000000, /* STRING */
|
|
000000 /* NAME */
|
|
};
|
|
|
|
const char ctaba[129] = {
|
|
EOFC, /* -1 */
|
|
EOFC, UNKN, UNKN, UNKN, UNKN, UNKN, UNKN, UNKN,
|
|
LETTER, SPACE, NEWLN, SPACE, SPACE, UNKN, UNKN, UNKN,
|
|
UNKN, UNKN, UNKN, UNKN, UNKN, UNKN, UNKN, UNKN,
|
|
UNKN, UNKN, UNKN, UNKN, UNKN, UNKN, UNKN, UNKN,
|
|
SPACE, EXCLA, DQUOTE, HASH, UNKN, MOD, AND, SQUOTE,
|
|
LPARN, RPARN, TIMES, PLUS, COMMA, MINUS, UNKN, DIVIDE,
|
|
DIGIT, DIGIT, DIGIT, DIGIT, DIGIT, DIGIT, DIGIT, DIGIT,
|
|
DIGIT, DIGIT, COLON, SEMI, LESS, ASSIGN, GREAT, QUEST,
|
|
UNKN, LETTER, LETTER, LETTER, LETTER, LETTER, LETTER, LETTER,
|
|
LETTER, LETTER, LETTER, LETTER, LETTER, LETTER, LETTER, LETTER,
|
|
LETTER, LETTER, LETTER, LETTER, LETTER, LETTER, LETTER, LETTER,
|
|
LETTER, LETTER, LETTER, LBRACK, UNKN, RBRACK, EOR, LETTER,
|
|
UNKN, LETTER, LETTER, LETTER, LETTER, LETTER, LETTER, LETTER,
|
|
LETTER, LETTER, LETTER, LETTER, LETTER, LETTER, LETTER, LETTER,
|
|
LETTER, LETTER, LETTER, LETTER, LETTER, LETTER, LETTER, LETTER,
|
|
LETTER, LETTER, LETTER, LBRACE, OR, RBRACE, NOT, UNKN
|
|
};
|
|
const char* ctab = &ctaba[1]; /* allows indexing with -1 */
|
|
|
|
/* debug function */
|
|
void printtoken(int tok, FILE *out)
|
|
{
|
|
static char *strtab[128];
|
|
strtab[0] = "EOFC";
|
|
strtab[1] = "SEMI";
|
|
strtab[2] = "LBRACE";
|
|
strtab[3] = "RBRACE";
|
|
strtab[4] = "LBRACK";
|
|
strtab[5] = "RBRACK";
|
|
strtab[6] = "LPARN";
|
|
strtab[7] = "RPARN";
|
|
strtab[8] = "COLON";
|
|
strtab[9] = "COMMA";
|
|
strtab[10] = "HASH";
|
|
|
|
strtab[15] = "MCALL";
|
|
strtab[16] = "CALL";
|
|
strtab[17] = "DECBEF";
|
|
strtab[18] = "INCBEF";
|
|
strtab[19] = "DECAFT";
|
|
strtab[20] = "INCAFT";
|
|
strtab[21] = "EXCLA";
|
|
strtab[22] = "NEG";
|
|
strtab[23] = "AMPER";
|
|
strtab[24] = "STAR";
|
|
strtab[25] = "QUEST";
|
|
strtab[26] = "NOT";
|
|
|
|
strtab[30] = "PLUS";
|
|
strtab[31] = "MINUS";
|
|
strtab[32] = "MOD";
|
|
strtab[33] = "TIMES";
|
|
strtab[34] = "DIVIDE";
|
|
strtab[35] = "OR";
|
|
strtab[36] = "AND";
|
|
strtab[37] = "LSHIFT";
|
|
strtab[38] = "RSHIFT";
|
|
strtab[39] = "EQUAL";
|
|
strtab[40] = "NEQUAL";
|
|
strtab[41] = "LESSEQ";
|
|
strtab[42] = "LESS";
|
|
strtab[43] = "GREATEQ";
|
|
strtab[44] = "GREAT";
|
|
strtab[45] = "EOR";
|
|
|
|
strtab[49] = "ASSIGN";
|
|
strtab[50] = "ASPLUS";
|
|
strtab[51] = "ASMINUS";
|
|
strtab[52] = "ASMOD";
|
|
strtab[53] = "ASTIMES";
|
|
strtab[54] = "ASDIV";
|
|
strtab[55] = "ASOR";
|
|
strtab[56] = "ASAND";
|
|
strtab[57] = "ASLSH";
|
|
strtab[58] = "ASRSH";
|
|
strtab[59] = "ASEQUAL";
|
|
strtab[60] = "ASNEQL";
|
|
strtab[61] = "ASLEQ";
|
|
strtab[62] = "ASLESS";
|
|
strtab[63] = "ASGTQ";
|
|
strtab[64] = "ASGREAT";
|
|
strtab[65] = "ASEOR";
|
|
|
|
strtab[70] = "CON";
|
|
strtab[71] = "STRING";
|
|
strtab[72] = "NAME";
|
|
strtab[73] = "KEYW";
|
|
|
|
strtab[127] = "UNKN";
|
|
|
|
if (tok == CON || tok == STRING) {
|
|
fprintf(out, "%s(%d) ", strtab[tok], cval);
|
|
return;
|
|
}
|
|
if (tok == NAME) {
|
|
fprintf(out, "%s(%s) ", strtab[tok], symbuf);
|
|
return;
|
|
}
|
|
|
|
fprintf(out, "%s ", strtab[tok]);
|
|
}
|
|
|