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efl/src/bin/embryo/embryo_cc_sc1.c

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/* Small compiler
* Function and variable definition and declaration, statement parser.
*
* Copyright (c) ITB CompuPhase, 1997-2003
*
* This software is provided "as-is", without any express or implied
* warranty. In no event will the authors be held liable for any
* damages arising from the use of this software. Permission is granted
* to anyone to use this software for any purpose, including commercial
* applications, and to alter it and redistribute it freely, subject to
* the following restrictions:
*
* 1. The origin of this software must not be misrepresented;
* you must not claim that you wrote the original software.
* If you use this software in a product, an acknowledgment in the
* product documentation would be appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and
* must not be misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source
* distribution.
* Version: $Id$
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <assert.h>
#include <ctype.h>
#include <limits.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#ifdef HAVE_EVIL
# include <Evil.h>
#endif
#include <Eina.h>
#include "embryo_cc_sc.h"
#include "embryo_cc_prefix.h"
#define VERSION_STR "2.4"
#define VERSION_INT 240
static void resetglobals(void);
static void initglobals(void);
static void setopt(int argc, char **argv,
char *iname, char *oname,
char *pname, char *rname);
static void setconfig(char *root);
static void about(void);
static void setconstants(void);
static void parse(void);
static void dumplits(void);
static void dumpzero(int count);
static void declfuncvar(int tok, char *symname,
int tag, int fpublic,
int fstatic, int fstock, int fconst);
static void declglb(char *firstname, int firsttag,
int fpublic, int fstatic, int stock, int fconst);
static int declloc(int fstatic);
static void decl_const(int table);
static void decl_enum(int table);
static cell needsub(int *tag);
static void initials(int ident, int tag,
cell * size, int dim[], int numdim);
static cell initvector(int ident, int tag, cell size, int fillzero);
static cell init(int ident, int *tag);
static void funcstub(int native);
static int newfunc(char *firstname, int firsttag,
int fpublic, int fstatic, int stock);
static int declargs(symbol * sym);
static void doarg(char *name, int ident, int offset,
int tags[], int numtags,
int fpublic, int fconst, arginfo * arg);
static void reduce_referrers(symbol * root);
static int testsymbols(symbol * root, int level,
int testlabs, int testconst);
static void destructsymbols(symbol * root, int level);
static constvalue *find_constval_byval(constvalue * table, cell val);
static void statement(int *lastindent, int allow_decl);
static void compound(void);
static void doexpr(int comma, int chkeffect,
int allowarray, int mark_endexpr,
int *tag, int chkfuncresult);
static void doassert(void);
static void doexit(void);
static void test(int label, int parens, int invert);
static void doif(void);
static void dowhile(void);
static void dodo(void);
static void dofor(void);
static void doswitch(void);
static void dogoto(void);
static void dolabel(void);
static symbol *fetchlab(char *name);
static void doreturn(void);
static void dobreak(void);
static void docont(void);
static void dosleep(void);
static void addwhile(int *ptr);
static void delwhile(void);
static int *readwhile(void);
static int lastst = 0; /* last executed statement type */
static int nestlevel = 0; /* number of active (open) compound statements */
static int rettype = 0; /* the type that a "return" expression should have */
static int skipinput = 0; /* number of lines to skip from the first input file */
static int wq[wqTABSZ]; /* "while queue", internal stack for nested loops */
static int *wqptr; /* pointer to next entry */
static char binfname[PATH_MAX]; /* binary file name */
int
main(int argc, char *argv[], char *env[] EINA_UNUSED)
{
e_prefix_determine(argv[0]);
return sc_compile(argc, argv);
}
int
sc_error(int number, char *message, char *filename, int firstline,
int lastline, va_list argptr)
{
static char *prefix[3] = { "error", "fatal error", "warning" };
if (number != 0)
{
char *pre;
pre = prefix[number / 100];
if (firstline >= 0)
fprintf(stderr, "%s(%d -- %d) : %s %03d: ", filename, firstline,
lastline, pre, number);
else
fprintf(stderr, "%s(%d) : %s %03d: ", filename, lastline, pre,
number);
} /* if */
vfprintf(stderr, message, argptr);
fflush(stderr);
return 0;
}
void *
sc_opensrc(char *filename)
{
return fopen(filename, "rb");
}
void
sc_closesrc(void *handle)
{
assert(handle != NULL);
fclose((FILE *) handle);
}
void
sc_resetsrc(void *handle, void *position)
{
assert(handle != NULL);
fsetpos((FILE *) handle, (fpos_t *) position);
}
char *
sc_readsrc(void *handle, char *target, int maxchars)
{
return fgets(target, maxchars, (FILE *) handle);
}
void *
sc_getpossrc(void *handle)
{
static fpos_t lastpos; /* may need to have a LIFO stack of
* such positions */
fgetpos((FILE *) handle, &lastpos);
return &lastpos;
}
int
sc_eofsrc(void *handle)
{
return feof((FILE *) handle);
}
void *
sc_openasm(int fd)
{
return fdopen(fd, "w+");
}
void
sc_closeasm(void *handle)
{
if (handle)
fclose((FILE *) handle);
}
void
sc_resetasm(void *handle)
{
fflush((FILE *) handle);
fseek((FILE *) handle, 0, SEEK_SET);
}
int
sc_writeasm(void *handle, char *st)
{
return fputs(st, (FILE *) handle) >= 0;
}
char *
sc_readasm(void *handle, char *target, int maxchars)
{
return fgets(target, maxchars, (FILE *) handle);
}
void *
sc_openbin(char *filename)
{
return fopen(filename, "wb");
}
void
sc_closebin(void *handle, int deletefile)
{
fclose((FILE *) handle);
if (deletefile)
unlink(binfname);
}
void
sc_resetbin(void *handle)
{
fflush((FILE *) handle);
fseek((FILE *) handle, 0, SEEK_SET);
}
int
sc_writebin(void *handle, void *buffer, int size)
{
return (int)fwrite(buffer, 1, size, (FILE *) handle) == size;
}
long
sc_lengthbin(void *handle)
{
return ftell((FILE *) handle);
}
/* "main" of the compiler
*/
int
sc_compile(int argc, char *argv[])
{
int entry, i, jmpcode, fd_out;
int retcode;
char incfname[PATH_MAX];
char reportname[PATH_MAX];
FILE *binf;
void *inpfmark;
char lcl_ctrlchar;
int lcl_packstr, lcl_needsemicolon, lcl_tabsize;
char *tmpdir;
/* set global variables to their initial value */
binf = NULL;
initglobals();
errorset(sRESET);
errorset(sEXPRRELEASE);
lexinit();
/* make sure that we clean up on a fatal error; do this before the
* first call to error(). */
if ((jmpcode = setjmp(errbuf)) != 0)
goto cleanup;
/* allocate memory for fixed tables */
inpfname = (char *)malloc(PATH_MAX);
litq = (cell *) malloc(litmax * sizeof(cell));
if (!litq)
error(103); /* insufficient memory */
if (!phopt_init())
error(103); /* insufficient memory */
setopt(argc, argv, inpfname, binfname, incfname, reportname);
/* open the output file */
#ifndef HAVE_EVIL
tmpdir = getenv("TMPDIR");
if (!tmpdir) tmpdir = "/tmp";
#else
tmpdir = (char *)evil_tmpdir_get();
#endif /* ! HAVE_EVIL */
snprintf(outfname, PATH_MAX, "%s/embryo_cc.asm-tmp-XXXXXX", tmpdir);
fd_out = mkstemp(outfname);
if (fd_out < 0)
error(101, outfname);
setconfig(argv[0]); /* the path to the include files */
lcl_ctrlchar = sc_ctrlchar;
lcl_packstr = sc_packstr;
lcl_needsemicolon = sc_needsemicolon;
lcl_tabsize = sc_tabsize;
inpf = inpf_org = (FILE *) sc_opensrc(inpfname);
if (!inpf)
error(100, inpfname);
freading = TRUE;
outf = (FILE *) sc_openasm(fd_out); /* first write to assembler
* file (may be temporary) */
if (!outf)
error(101, outfname);
/* immediately open the binary file, for other programs to check */
binf = (FILE *) sc_openbin(binfname);
if (!binf)
error(101, binfname);
setconstants(); /* set predefined constants and tagnames */
for (i = 0; i < skipinput; i++) /* skip lines in the input file */
if (sc_readsrc(inpf, pline, sLINEMAX))
fline++; /* keep line number up to date */
skipinput = fline;
sc_status = statFIRST;
/* do the first pass through the file */
inpfmark = sc_getpossrc(inpf);
if (incfname[0] != '\0')
{
if (strcmp(incfname, sDEF_PREFIX) == 0)
{
plungefile(incfname, FALSE, TRUE); /* parse "default.inc" */
}
else
{
if (!plungequalifiedfile(incfname)) /* parse "prefix" include
* file */
error(100, incfname); /* cannot read from ... (fatal error) */
} /* if */
} /* if */
preprocess(); /* fetch first line */
parse(); /* process all input */
/* second pass */
sc_status = statWRITE; /* set, to enable warnings */
/* ??? for re-parsing the listing file instead of the original source
* file (and doing preprocessing twice):
* - close input file, close listing file
* - re-open listing file for reading (inpf)
* - open assembler file (outf)
*/
/* reset "defined" flag of all functions and global variables */
reduce_referrers(&glbtab);
delete_symbols(&glbtab, 0, TRUE, FALSE);
#if !defined NO_DEFINE
delete_substtable();
#endif
resetglobals();
sc_ctrlchar = lcl_ctrlchar;
sc_packstr = lcl_packstr;
sc_needsemicolon = lcl_needsemicolon;
sc_tabsize = lcl_tabsize;
errorset(sRESET);
/* reset the source file */
inpf = inpf_org;
freading = TRUE;
sc_resetsrc(inpf, inpfmark); /* reset file position */
fline = skipinput; /* reset line number */
lexinit(); /* clear internal flags of lex() */
sc_status = statWRITE; /* allow to write --this variable was reset
* by resetglobals() */
writeleader();
setfile(inpfname, fnumber);
if (incfname[0] != '\0')
{
if (strcmp(incfname, sDEF_PREFIX) == 0)
plungefile(incfname, FALSE, TRUE); /* parse "default.inc" (again) */
else
plungequalifiedfile(incfname); /* parse implicit include
* file (again) */
} /* if */
preprocess(); /* fetch first line */
parse(); /* process all input */
/* inpf is already closed when readline() attempts to pop of a file */
writetrailer(); /* write remaining stuff */
entry = testsymbols(&glbtab, 0, TRUE, FALSE); /* test for unused
* or undefined functions and variables */
if (!entry)
error(13); /* no entry point (no public functions) */
cleanup:
if (inpf) /* main source file is not closed, do it now */
sc_closesrc(inpf);
/* write the binary file (the file is already open) */
if (errnum == 0 && jmpcode == 0)
{
assert(binf != NULL);
sc_resetasm(outf); /* flush and loop back, for reading */
assemble(binf, outf); /* assembler file is now input */
} /* if */
if (outf)
sc_closeasm(outf);
unlink (outfname);
if (binf)
sc_closebin(binf, errnum != 0);
if (inpfname)
free(inpfname);
if (litq)
free(litq);
phopt_cleanup();
stgbuffer_cleanup();
assert(jmpcode != 0 || loctab.next == NULL); /* on normal flow,
* local symbols
* should already have been deleted */
delete_symbols(&loctab, 0, TRUE, TRUE); /* delete local variables
* if not yet done (i.e.
* on a fatal error) */
delete_symbols(&glbtab, 0, TRUE, TRUE);
delete_consttable(&tagname_tab);
delete_consttable(&libname_tab);
delete_aliastable();
delete_pathtable();
#if !defined NO_DEFINE
delete_substtable();
#endif
if (errnum != 0)
{
printf("\n%d Error%s.\n", errnum, (errnum > 1) ? "s" : "");
retcode = 2;
}
else if (warnnum != 0)
{
printf("\n%d Warning%s.\n", warnnum, (warnnum > 1) ? "s" : "");
retcode = 1;
}
else
{
retcode = jmpcode;
} /* if */
return retcode;
}
int
sc_addconstant(char *name, cell value, int tag)
{
errorset(sFORCESET); /* make sure error engine is silenced */
sc_status = statIDLE;
add_constant(name, value, sGLOBAL, tag);
return 1;
}
int
sc_addtag(char *name)
{
cell val;
constvalue *ptr;
int last, tag;
if (!name)
{
/* no tagname was given, check for one */
if (lex(&val, &name) != tLABEL)
{
lexpush();
return 0; /* untagged */
} /* if */
} /* if */
last = 0;
ptr = tagname_tab.next;
while (ptr)
{
tag = (int)(ptr->value & TAGMASK);
if (strcmp(name, ptr->name) == 0)
return tag; /* tagname is known, return its sequence number */
tag &= (int)~FIXEDTAG;
if (tag > last)
last = tag;
ptr = ptr->next;
} /* while */
/* tagname currently unknown, add it */
tag = last + 1; /* guaranteed not to exist already */
if (sc_isupper(*name))
tag |= (int)FIXEDTAG;
append_constval(&tagname_tab, name, (cell) tag, 0);
return tag;
}
static void
resetglobals(void)
{
/* reset the subset of global variables that is modified by the
* first pass */
curfunc = NULL; /* pointer to current function */
lastst = 0; /* last executed statement type */
nestlevel = 0; /* number of active (open) compound statements */
rettype = 0; /* the type that a "return" expression should have */
litidx = 0; /* index to literal table */
stgidx = 0; /* index to the staging buffer */
labnum = 0; /* number of (internal) labels */
staging = 0; /* true if staging output */
declared = 0; /* number of local cells declared */
glb_declared = 0; /* number of global cells declared */
code_idx = 0; /* number of bytes with generated code */
ntv_funcid = 0; /* incremental number of native function */
curseg = 0; /* 1 if currently parsing CODE, 2 if parsing DATA */
freading = FALSE; /* no input file ready yet */
fline = 0; /* the line number in the current file */
fnumber = 0; /* the file number in the file table (debugging) */
fcurrent = 0; /* current file being processed (debugging) */
intest = 0; /* true if inside a test */
sideeffect = 0; /* true if an expression causes a side-effect */
stmtindent = 0; /* current indent of the statement */
indent_nowarn = TRUE; /* do not skip warning "217 loose indentation" */
sc_allowtags = TRUE; /* allow/detect tagnames */
sc_status = statIDLE;
}
static void
initglobals(void)
{
resetglobals();
skipinput = 0; /* number of lines to skip from the first
* input file */
sc_ctrlchar = CTRL_CHAR; /* the escape character */
litmax = sDEF_LITMAX; /* current size of the literal table */
errnum = 0; /* number of errors */
warnnum = 0; /* number of warnings */
/* sc_debug=sCHKBOUNDS; by default: bounds checking+assertions */
sc_debug = 0; /* by default: no debug */
charbits = 8; /* a "char" is 8 bits */
sc_packstr = FALSE; /* strings are unpacked by default */
/* sc_compress=TRUE; compress output bytecodes */
sc_compress = FALSE; /* compress output bytecodes */
sc_needsemicolon = FALSE; /* semicolon required to terminate
* expressions? */
sc_dataalign = 4;
sc_stksize = sDEF_AMXSTACK; /* default stack size */
sc_tabsize = 8; /* assume a TAB is 8 spaces */
sc_rationaltag = 0; /* assume no support for rational numbers */
rational_digits = 0; /* number of fractional digits */
outfname[0] = '\0'; /* output file name */
inpf = NULL; /* file read from */
inpfname = NULL; /* pointer to name of the file currently
* read from */
outf = NULL; /* file written to */
litq = NULL; /* the literal queue */
glbtab.next = NULL; /* clear global variables/constants table */
loctab.next = NULL; /* " local " / " " */
tagname_tab.next = NULL; /* tagname table */
libname_tab.next = NULL; /* library table (#pragma library "..."
* syntax) */
pline[0] = '\0'; /* the line read from the input file */
lptr = NULL; /* points to the current position in "pline" */
curlibrary = NULL; /* current library */
inpf_org = NULL; /* main source file */
wqptr = wq; /* initialize while queue pointer */
}
static void
parseoptions(int argc, char **argv, char *iname, char *oname,
char *pname EINA_UNUSED, char *rname EINA_UNUSED)
{
char str[PATH_MAX];
int i, stack_size;
size_t len;
/* use embryo include dir always */
snprintf(str, sizeof(str), "%s/include/", e_prefix_data_get());
insert_path(str);
insert_path("./");
for (i = 1; i < argc; i++)
{
if (!strcmp (argv[i], "-i") && (i + 1 < argc) && *argv[i + 1])
{
/* include directory */
i++;
strncpy(str, argv[i], sizeof(str));
len = strlen(str);
if (str[len - 1] != DIRSEP_CHAR)
{
str[len] = DIRSEP_CHAR;
str[len + 1] = '\0';
}
insert_path(str);
}
else if (!strcmp (argv[i], "-o") && (i + 1 < argc) && *argv[i + 1])
{
/* output file */
i++;
strcpy(oname, argv[i]); /* FIXME */
}
else if (!strcmp (argv[i], "-S") && (i + 1 < argc) && *argv[i + 1])
{
/* stack size */
i++;
stack_size = atoi(argv[i]);
if (stack_size > 64)
sc_stksize = (cell) stack_size;
else
about();
}
else if (!*iname)
{
/* input file */
strcpy(iname, argv[i]); /* FIXME */
}
else
{
/* only allow one input filename */
about();
}
}
}
static void
setopt(int argc, char **argv, char *iname, char *oname,
char *pname, char *rname)
{
*iname = '\0';
*oname = '\0';
*pname = '\0';
*rname = '\0';
strcpy(pname, sDEF_PREFIX);
parseoptions(argc, argv, iname, oname, pname, rname);
if (iname[0] == '\0')
about();
}
static void
setconfig(char *root)
{
char path[PATH_MAX];
char *ptr;
int len;
path[sizeof(path) - 1] = 0;
/* add the default "include" directory */
if (root)
{
/* path + filename (hopefully) */
strncpy(path, root, sizeof(path) - 1);
path[sizeof(path) - 1] = 0;
}
/* terminate just behind last \ or : */
if ((ptr = strrchr(path, DIRSEP_CHAR))
|| (ptr = strchr(path, ':')))
{
/* If there was no terminating "\" or ":",
* the filename probably does not
* contain the path; so we just don't add it
* to the list in that case
*/
*(ptr + 1) = '\0';
if (strlen(path) < (sizeof(path) - 1 - 7))
{
strcat(path, "include");
}
len = strlen(path);
path[len] = DIRSEP_CHAR;
path[len + 1] = '\0';
insert_path(path);
} /* if */
}
static void
about(void)
{
printf("Usage: embryo_cc <filename> [options]\n\n");
printf("Options:\n");
#if 0
printf
(" -A<num> alignment in bytes of the data segment and the\
stack\n");
printf
(" -a output assembler code (skip code generation\
pass)\n");
printf
(" -C[+/-] compact encoding for output file (default=%c)\n",
sc_compress ? '+' : '-');
printf(" -c8 [default] a character is 8-bits\
(ASCII/ISO Latin-1)\n");
printf(" -c16 a character is 16-bits (Unicode)\n");
#if defined dos_setdrive
printf(" -Dpath active directory path\n");
#endif
printf
(" -d0 no symbolic information, no run-time checks\n");
printf(" -d1 [default] run-time checks, no symbolic\
information\n");
printf
(" -d2 full debug information and dynamic checking\n");
printf(" -d3 full debug information, dynamic checking,\
no optimization\n");
#endif
printf(" -i <name> path for include files\n");
#if 0
printf(" -l create list file (preprocess only)\n");
#endif
printf(" -o <name> set base name of output file\n");
#if 0
printf
(" -P[+/-] strings are \"packed\" by default (default=%c)\n",
sc_packstr ? '+' : '-');
printf(" -p<name> set name of \"prefix\" file\n");
if (!waitkey())
longjmp(errbuf, 3);
#endif
printf
(" -S <num> stack/heap size in cells (default=%d, min=65)\n",
(int)sc_stksize);
#if 0
printf(" -s<num> skip lines from the input file\n");
printf
(" -t<num> TAB indent size (in character positions)\n");
printf(" -\\ use '\\' for escape characters\n");
printf(" -^ use '^' for escape characters\n");
printf(" -;[+/-] require a semicolon to end each statement\
(default=%c)\n", sc_needsemicolon ? '+' : '-');
printf
(" sym=val define constant \"sym\" with value \"val\"\n");
printf(" sym= define constant \"sym\" with value 0\n");
#endif
longjmp(errbuf, 3); /* user abort */
}
static void
setconstants(void)
{
int debug;
assert(sc_status == statIDLE);
append_constval(&tagname_tab, "_", 0, 0); /* "untagged" */
append_constval(&tagname_tab, "bool", 1, 0);
add_constant("true", 1, sGLOBAL, 1); /* boolean flags */
add_constant("false", 0, sGLOBAL, 1);
add_constant("EOS", 0, sGLOBAL, 0); /* End Of String, or '\0' */
add_constant("cellbits", 32, sGLOBAL, 0);
add_constant("cellmax", INT_MAX, sGLOBAL, 0);
add_constant("cellmin", INT_MIN, sGLOBAL, 0);
add_constant("charbits", charbits, sGLOBAL, 0);
add_constant("charmin", 0, sGLOBAL, 0);
add_constant("charmax", (charbits == 16) ? 0xffff : 0xff, sGLOBAL, 0);
add_constant("__Small", VERSION_INT, sGLOBAL, 0);
debug = 0;
if ((sc_debug & (sCHKBOUNDS | sSYMBOLIC)) == (sCHKBOUNDS | sSYMBOLIC))
debug = 2;
else if ((sc_debug & sCHKBOUNDS) == sCHKBOUNDS)
debug = 1;
add_constant("debug", debug, sGLOBAL, 0);
}
/* parse - process all input text
*
* At this level, only static declarations and function definitions
* are legal.
*/
static void
parse(void)
{
int tok, tag, fconst, fstock, fstatic;
cell val;
char *str;
while (freading)
{
/* first try whether a declaration possibly is native or public */
tok = lex(&val, &str); /* read in (new) token */
switch (tok)
{
case 0:
/* ignore zero's */
break;
case tNEW:
fconst = matchtoken(tCONST);
declglb(NULL, 0, FALSE, FALSE, FALSE, fconst);
break;
case tSTATIC:
/* This can be a static function or a static global variable;
* we know which of the two as soon as we have parsed up to the
* point where an opening parenthesis of a function would be
* expected. To back out after deciding it was a declaration of
* a static variable after all, we have to store the symbol name
* and tag.
*/
fstock = matchtoken(tSTOCK);
fconst = matchtoken(tCONST);
tag = sc_addtag(NULL);
tok = lex(&val, &str);
if (tok == tNATIVE || tok == tPUBLIC)
{
error(42); /* invalid combination of class specifiers */
break;
} /* if */
declfuncvar(tok, str, tag, FALSE, TRUE, fstock, fconst);
break;
case tCONST:
decl_const(sGLOBAL);
break;
case tENUM:
decl_enum(sGLOBAL);
break;
case tPUBLIC:
/* This can be a public function or a public variable;
* see the comment above (for static functions/variables)
* for details.
*/
fconst = matchtoken(tCONST);
tag = sc_addtag(NULL);
tok = lex(&val, &str);
if (tok == tNATIVE || tok == tSTOCK || tok == tSTATIC)
{
error(42); /* invalid combination of class specifiers */
break;
} /* if */
declfuncvar(tok, str, tag, TRUE, FALSE, FALSE, fconst);
break;
case tSTOCK:
/* This can be a stock function or a stock *global) variable;
* see the comment above (for static functions/variables) for
* details.
*/
fstatic = matchtoken(tSTATIC);
fconst = matchtoken(tCONST);
tag = sc_addtag(NULL);
tok = lex(&val, &str);
if (tok == tNATIVE || tok == tPUBLIC)
{
error(42); /* invalid combination of class specifiers */
break;
} /* if */
declfuncvar(tok, str, tag, FALSE, fstatic, TRUE, fconst);
break;
case tLABEL:
case tSYMBOL:
case tOPERATOR:
lexpush();
if (!newfunc(NULL, -1, FALSE, FALSE, FALSE))
{
error(10); /* illegal function or declaration */
lexclr(TRUE); /* drop the rest of the line */
} /* if */
break;
case tNATIVE:
funcstub(TRUE); /* create a dummy function */
break;
case tFORWARD:
funcstub(FALSE);
break;
case '}':
error(54); /* unmatched closing brace */
break;
case '{':
error(55); /* start of function body without function header */
break;
default:
if (freading)
{
error(10); /* illegal function or declaration */
lexclr(TRUE); /* drop the rest of the line */
} /* if */
} /* switch */
} /* while */
}
/* dumplits
*
* Dump the literal pool (strings etc.)
*
* Global references: litidx (referred to only)
*/
static void
dumplits(void)
{
int j, k;
k = 0;
while (k < litidx)
{
/* should be in the data segment */
assert(curseg == 2);
defstorage();
j = 16; /* 16 values per line */
while (j && k < litidx)
{
outval(litq[k], FALSE);
stgwrite(" ");
k++;
j--;
if (j == 0 || k >= litidx)
stgwrite("\n"); /* force a newline after 10 dumps */
/* Note: stgwrite() buffers a line until it is complete. It recognizes
* the end of line as a sequence of "\n\0", so something like "\n\t"
* so should not be passed to stgwrite().
*/
} /* while */
} /* while */
}
/* dumpzero
*
* Dump zero's for default initial values
*/
static void
dumpzero(int count)
{
int i;
if (count <= 0)
return;
assert(curseg == 2);
defstorage();
i = 0;
while (count-- > 0)
{
outval(0, FALSE);
i = (i + 1) % 16;
stgwrite((i == 0 || count == 0) ? "\n" : " ");
if (i == 0 && count > 0)
defstorage();
} /* while */
}
static void
aligndata(int numbytes)
{
if ((((glb_declared + litidx) * sizeof(cell)) % numbytes) != 0)
{
while ((((glb_declared + litidx) * sizeof(cell)) % numbytes) != 0)
stowlit(0);
} /* if */
}
static void
declfuncvar(int tok, char *symname, int tag, int fpublic, int fstatic,
int fstock, int fconst)
{
char name[sNAMEMAX + 1];
if (tok != tSYMBOL && tok != tOPERATOR)
{
if (freading)
error(20, symname); /* invalid symbol name */
return;
} /* if */
if (tok == tOPERATOR)
{
lexpush();
if (!newfunc(NULL, tag, fpublic, fstatic, fstock))
error(10); /* illegal function or declaration */
}
else
{
assert(strlen(symname) <= sNAMEMAX);
strcpy(name, symname);
if (fconst || !newfunc(name, tag, fpublic, fstatic, fstock))
declglb(name, tag, fpublic, fstatic, fstock, fconst);
/* if not a static function, try a static variable */
} /* if */
}
/* declglb - declare global symbols
*
* Declare a static (global) variable. Global variables are stored in
* the DATA segment.
*
* global references: glb_declared (altered)
*/
static void
declglb(char *firstname, int firsttag, int fpublic, int fstatic,
int stock, int fconst)
{
int ident, tag, ispublic;
int idxtag[sDIMEN_MAX];
char name[sNAMEMAX + 1];
cell val, size, cidx;
char *str;
int dim[sDIMEN_MAX];
int numdim, level;
int filenum;
symbol *sym;
#if !defined NDEBUG
cell glbdecl = 0;
#endif
filenum = fcurrent; /* save file number at the start of the
* declaration */
do
{
size = 1; /* single size (no array) */
numdim = 0; /* no dimensions */
ident = iVARIABLE;
if (firstname)
{
assert(strlen(firstname) <= sNAMEMAX);
strcpy(name, firstname); /* save symbol name */
tag = firsttag;
firstname = NULL;
}
else
{
tag = sc_addtag(NULL);
if (lex(&val, &str) != tSYMBOL) /* read in (new) token */
error(20, str); /* invalid symbol name */
assert(strlen(str) <= sNAMEMAX);
strcpy(name, str); /* save symbol name */
} /* if */
sym = findglb(name);
if (!sym)
sym = findconst(name);
if (sym && (sym->usage & uDEFINE) != 0)
error(21, name); /* symbol already defined */
ispublic = fpublic;
if (name[0] == PUBLIC_CHAR)
{
ispublic = TRUE; /* implicitly public variable */
if (stock || fstatic)
error(42); /* invalid combination of class specifiers */
} /* if */
while (matchtoken('['))
{
ident = iARRAY;
if (numdim == sDIMEN_MAX)
{
error(53); /* exceeding maximum number of dimensions */
return;
} /* if */
if (numdim > 0 && dim[numdim - 1] == 0)
error(52); /* only last dimension may be variable length */
size = needsub(&idxtag[numdim]); /* get size; size==0 for
* "var[]" */
#if INT_MAX < LONG_MAX
if (size > INT_MAX)
error(105); /* overflow, exceeding capacity */
#endif
if (ispublic)
error(56, name); /* arrays cannot be public */
dim[numdim++] = (int)size;
} /* while */
/* if this variable is never used (which can be detected only in
* the second stage), shut off code generation; make an exception
* for public variables
*/
cidx = 0; /* only to avoid a compiler warning */
if (sc_status == statWRITE && sym
&& (sym->usage & (uREAD | uWRITTEN | uPUBLIC)) == 0)
{
sc_status = statSKIP;
cidx = code_idx;
#if !defined NDEBUG
glbdecl = glb_declared;
#endif
} /* if */
defsymbol(name, ident, sGLOBAL, sizeof(cell) * glb_declared, tag);
begdseg(); /* real (initialized) data in data segment */
assert(litidx == 0); /* literal queue should be empty */
if (sc_alignnext)
{
litidx = 0;
aligndata(sc_dataalign);
dumplits(); /* dump the literal queue */
sc_alignnext = FALSE;
litidx = 0; /* global initial data is dumped, so restart at zero */
} /* if */
initials(ident, tag, &size, dim, numdim); /* stores values in
* the literal queue */
if (numdim == 1)
dim[0] = (int)size;
dumplits(); /* dump the literal queue */
dumpzero((int)size - litidx);
litidx = 0;
if (!sym)
{ /* define only if not yet defined */
sym =
addvariable(name, sizeof(cell) * glb_declared, ident, sGLOBAL,
tag, dim, numdim, idxtag);
}
else
{ /* if declared but not yet defined, adjust the
* variable's address */
sym->addr = sizeof(cell) * glb_declared;
sym->usage |= uDEFINE;
} /* if */
if (ispublic)
sym->usage |= uPUBLIC;
if (fconst)
sym->usage |= uCONST;
if (stock)
sym->usage |= uSTOCK;
if (fstatic)
sym->fnumber = filenum;
if (ident == iARRAY)
for (level = 0; level < numdim; level++)
symbolrange(level, dim[level]);
if (sc_status == statSKIP)
{
sc_status = statWRITE;
code_idx = cidx;
assert(glb_declared == glbdecl);
}
else
{
glb_declared += (int)size; /* add total number of cells */
} /* if */
}
while (matchtoken(',')); /* enddo *//* more? */
needtoken(tTERM); /* if not comma, must be semicolumn */
}
/* declloc - declare local symbols
*
* Declare local (automatic) variables. Since these variables are
* relative to the STACK, there is no switch to the DATA segment.
* These variables cannot be initialized either.
*
* global references: declared (altered)
* funcstatus (referred to only)
*/
static int
declloc(int fstatic)
{
int ident, tag;
int idxtag[sDIMEN_MAX];
char name[sNAMEMAX + 1];
symbol *sym;
cell val, size;
char *str;
value lval = { NULL, 0, 0, 0, 0, NULL };
int cur_lit = 0;
int dim[sDIMEN_MAX];
int numdim, level;
int fconst;
fconst = matchtoken(tCONST);
do
{
ident = iVARIABLE;
size = 1;
numdim = 0; /* no dimensions */
tag = sc_addtag(NULL);
if (lex(&val, &str) != tSYMBOL) /* read in (new) token */
error(20, str); /* invalid symbol name */
assert(strlen(str) <= sNAMEMAX);
strcpy(name, str); /* save symbol name */
if (name[0] == PUBLIC_CHAR)
error(56, name); /* local variables cannot be public */
/* Note: block locals may be named identical to locals at higher
* compound blocks (as with standard C); so we must check (and add)
* the "nesting level" of local variables to verify the
* multi-definition of symbols.
*/
if ((sym = findloc(name)) && sym->compound == nestlevel)
error(21, name); /* symbol already defined */
/* Although valid, a local variable whose name is equal to that
* of a global variable or to that of a local variable at a lower
* level might indicate a bug.
*/
if (((sym = findloc(name)) && sym->compound != nestlevel)
|| findglb(name))
error(219, name); /* variable shadows another symbol */
while (matchtoken('['))
{
ident = iARRAY;
if (numdim == sDIMEN_MAX)
{
error(53); /* exceeding maximum number of dimensions */
return ident;
} /* if */
if (numdim > 0 && dim[numdim - 1] == 0)
error(52); /* only last dimension may be variable length */
size = needsub(&idxtag[numdim]); /* get size; size==0 for "var[]" */
#if INT_MAX < LONG_MAX
if (size > INT_MAX)
error(105); /* overflow, exceeding capacity */
#endif
dim[numdim++] = (int)size;
} /* while */
if (ident == iARRAY || fstatic)
{
if (sc_alignnext)
{
aligndata(sc_dataalign);
sc_alignnext = FALSE;
} /* if */
cur_lit = litidx; /* save current index in the literal table */
initials(ident, tag, &size, dim, numdim);
if (size == 0)
return ident; /* error message already given */
if (numdim == 1)
dim[0] = (int)size;
} /* if */
/* reserve memory (on the stack) for the variable */
if (fstatic)
{
/* write zeros for uninitialized fields */
while (litidx < cur_lit + size)
stowlit(0);
sym =
addvariable(name, (cur_lit + glb_declared) * sizeof(cell),
ident, sSTATIC, tag, dim, numdim, idxtag);
defsymbol(name, ident, sSTATIC,
(cur_lit + glb_declared) * sizeof(cell), tag);
}
else
{
declared += (int)size; /* variables are put on stack,
* adjust "declared" */
sym =
addvariable(name, -declared * sizeof(cell), ident, sLOCAL, tag,
dim, numdim, idxtag);
defsymbol(name, ident, sLOCAL, -declared * sizeof(cell), tag);
modstk(-(int)size * sizeof(cell));
} /* if */
/* now that we have reserved memory for the variable, we can
* proceed to initialize it */
sym->compound = nestlevel; /* for multiple declaration/shadowing */
if (fconst)
sym->usage |= uCONST;
if (ident == iARRAY)
for (level = 0; level < numdim; level++)
symbolrange(level, dim[level]);
if (!fstatic)
{ /* static variables already initialized */
if (ident == iVARIABLE)
{
/* simple variable, also supports initialization */
int ctag = tag; /* set to "tag" by default */
int explicit_init = FALSE; /* is the variable explicitly
* initialized? */
if (matchtoken('='))
{
doexpr(FALSE, FALSE, FALSE, FALSE, &ctag, TRUE);
explicit_init = TRUE;
}
else
{
const1(0); /* uninitialized variable, set to zero */
} /* if */
/* now try to save the value (still in PRI) in the variable */
lval.sym = sym;
lval.ident = iVARIABLE;
lval.constval = 0;
lval.tag = tag;
check_userop(NULL, ctag, lval.tag, 2, NULL, &ctag);
store(&lval);
endexpr(TRUE); /* full expression ends after the store */
if (!matchtag(tag, ctag, TRUE))
error(213); /* tag mismatch */
/* if the variable was not explicitly initialized, reset the
* "uWRITTEN" flag that store() set */
if (!explicit_init)
sym->usage &= ~uWRITTEN;
}
else
{
/* an array */
if (litidx - cur_lit < size)
fillarray(sym, size * sizeof(cell), 0);
if (cur_lit < litidx)
{
/* check whether the complete array is set to a single value;
* if it is, more compact code can be generated */
cell first = litq[cur_lit];
int i;
for (i = cur_lit; i < litidx && litq[i] == first; i++)
/* nothing */ ;
if (i == litidx)
{
/* all values are the same */
fillarray(sym, (litidx - cur_lit) * sizeof(cell),
first);
litidx = cur_lit; /* reset literal table */
}
else
{
/* copy the literals to the array */
const1((cur_lit + glb_declared) * sizeof(cell));
copyarray(sym, (litidx - cur_lit) * sizeof(cell));
} /* if */
} /* if */
} /* if */
} /* if */
}
while (matchtoken(',')); /* enddo *//* more? */
needtoken(tTERM); /* if not comma, must be semicolumn */
return ident;
}
static cell
calc_arraysize(int dim[], int numdim, int cur)
{
if (cur == numdim)
return 0;
return dim[cur] + (dim[cur] * calc_arraysize(dim, numdim, cur + 1));
}
/* initials
*
* Initialize global objects and local arrays.
* size==array cells (count), if 0 on input, the routine counts
* the number of elements
* tag==required tagname id (not the returned tag)
*
* Global references: litidx (altered)
*/
static void
initials(int ident, int tag, cell * size, int dim[], int numdim)
{
int ctag;
int curlit = litidx;
int d;
if (!matchtoken('='))
{
if (ident == iARRAY && dim[numdim - 1] == 0)
{
/* declared as "myvar[];" which is senseless (note: this *does* make
* sense in the case of a iREFARRAY, which is a function parameter)
*/
error(9); /* array has zero length -> invalid size */
} /* if */
if (numdim > 1)
{
/* initialize the indirection tables */
#if sDIMEN_MAX>2
#error Array algorithms for more than 2 dimensions are not implemented
#endif
assert(numdim == 2);
*size = calc_arraysize(dim, numdim, 0);
for (d = 0; d < dim[0]; d++)
stowlit((dim[0] + d * (dim[1] - 1)) * sizeof(cell));
} /* if */
return;
} /* if */
if (ident == iVARIABLE)
{
assert(*size == 1);
init(ident, &ctag);
if (!matchtag(tag, ctag, TRUE))
error(213); /* tag mismatch */
}
else
{
assert(numdim > 0);
if (numdim == 1)
{
*size = initvector(ident, tag, dim[0], FALSE);
}
else
{
cell offs, dsize;
/* The simple algorithm below only works for arrays with one or
* two dimensions. This should be some recursive algorithm.
*/
if (dim[numdim - 1] != 0)
/* set size to (known) full size */
*size = calc_arraysize(dim, numdim, 0);
/* dump indirection tables */
for (d = 0; d < dim[0]; d++)
stowlit(0);
/* now dump individual vectors */
needtoken('{');
offs = dim[0];
for (d = 0; d < dim[0]; d++)
{
litq[curlit + d] = offs * sizeof(cell);
dsize = initvector(ident, tag, dim[1], TRUE);
offs += dsize - 1;
if (d + 1 < dim[0])
needtoken(',');
if (matchtoken('{') || matchtoken(tSTRING))
/* expect a '{' or a string */
lexpush();
else
break;
} /* for */
matchtoken(',');
needtoken('}');
} /* if */
} /* if */
if (*size == 0)
*size = litidx - curlit; /* number of elements defined */
}
/* initvector
* Initialize a single dimensional array
*/
static cell
initvector(int ident, int tag, cell size, int fillzero)
{
cell prev1 = 0, prev2 = 0;
int ctag;
int ellips = FALSE;
int curlit = litidx;
assert(ident == iARRAY || ident == iREFARRAY);
if (matchtoken('{'))
{
do
{
if (matchtoken('}'))
{ /* to allow for trailing ',' after the initialization */
lexpush();
break;
} /* if */
if ((ellips = matchtoken(tELLIPS)) != 0)
break;
prev2 = prev1;
prev1 = init(ident, &ctag);
if (!matchtag(tag, ctag, TRUE))
error(213); /* tag mismatch */
}
while (matchtoken(',')); /* do */
needtoken('}');
}
else
{
init(ident, &ctag);
if (!matchtag(tag, ctag, TRUE))
error(213); /* tagname mismatch */
} /* if */
/* fill up the literal queue with a series */
if (ellips)
{
cell step =
((litidx - curlit) == 1) ? (cell) 0 : prev1 - prev2;
if (size == 0 || (litidx - curlit) == 0)
error(41); /* invalid ellipsis, array size unknown */
else if ((litidx - curlit) == (int)size)
error(18); /* initialisation data exceeds declared size */
while ((litidx - curlit) < (int)size)
{
prev1 += step;
stowlit(prev1);
} /* while */
} /* if */
if (fillzero && size > 0)
{
while ((litidx - curlit) < (int)size)
stowlit(0);
} /* if */
if (size == 0)
{
size = litidx - curlit; /* number of elements defined */
}
else if (litidx - curlit > (int)size)
{ /* e.g. "myvar[3]={1,2,3,4};" */
error(18); /* initialisation data exceeds declared size */
litidx = (int)size + curlit; /* avoid overflow in memory moves */
} /* if */
return size;
}
/* init
*
* Evaluate one initializer.
*/
static cell
init(int ident, int *tag)
{
cell i = 0;
if (matchtoken(tSTRING))
{
/* lex() automatically stores strings in the literal table (and
* increases "litidx") */
if (ident == iVARIABLE)
{
error(6); /* must be assigned to an array */
litidx = 1; /* reset literal queue */
} /* if */
*tag = 0;
}
else if (constexpr(&i, tag))
{
stowlit(i); /* store expression result in literal table */
} /* if */
return i;
}
/* needsub
*
* Get required array size
*/
static cell
needsub(int *tag)
{
cell val;
*tag = 0;
if (matchtoken(']')) /* we've already seen "[" */
return 0; /* null size (like "char msg[]") */
constexpr(&val, tag); /* get value (must be constant expression) */
if (val < 0)
{
error(9); /* negative array size is invalid; assumed zero */
val = 0;
} /* if */
needtoken(']');
return val; /* return array size */
}
/* decl_const - declare a single constant
*
*/
static void
decl_const(int vclass)
{
char constname[sNAMEMAX + 1];
cell val;
char *str;
int tag, exprtag;
int symbolline;
tag = sc_addtag(NULL);
if (lex(&val, &str) != tSYMBOL) /* read in (new) token */
error(20, str); /* invalid symbol name */
symbolline = fline; /* save line where symbol was found */
strcpy(constname, str); /* save symbol name */
needtoken('=');
constexpr(&val, &exprtag); /* get value */
needtoken(tTERM);
/* add_constant() checks for duplicate definitions */
if (!matchtag(tag, exprtag, FALSE))
{
/* temporarily reset the line number to where the symbol was
* defined */
int orgfline = fline;
fline = symbolline;
error(213); /* tagname mismatch */
fline = orgfline;
} /* if */
add_constant(constname, val, vclass, tag);
}
/* decl_enum - declare enumerated constants
*
*/
static void
decl_enum(int vclass)
{
char enumname[sNAMEMAX + 1], constname[sNAMEMAX + 1];
cell val, value, size;
char *str;
int tok, tag, explicittag;
cell increment, multiplier;
/* get an explicit tag, if any (we need to remember whether an
* explicit tag was passed, even if that explicit tag was "_:", so we
* cannot call sc_addtag() here
*/
if (lex(&val, &str) == tLABEL)
{
tag = sc_addtag(str);
explicittag = TRUE;
}
else
{
lexpush();
tag = 0;
explicittag = FALSE;
} /* if */
/* get optional enum name (also serves as a tag if no explicit
* tag was set) */
if (lex(&val, &str) == tSYMBOL)
{ /* read in (new) token */
strcpy(enumname, str); /* save enum name (last constant) */
if (!explicittag)
tag = sc_addtag(enumname);
}
else
{
lexpush(); /* analyze again */
enumname[0] = '\0';
} /* if */
/* get increment and multiplier */
increment = 1;
multiplier = 1;
if (matchtoken('('))
{
if (matchtoken(taADD))
{
constexpr(&increment, NULL);
}
else if (matchtoken(taMULT))
{
constexpr(&multiplier, NULL);
}
else if (matchtoken(taSHL))
{
constexpr(&val, NULL);
while (val-- > 0)
multiplier *= 2;
} /* if */
needtoken(')');
} /* if */
needtoken('{');
/* go through all constants */
value = 0; /* default starting value */
do
{
if (matchtoken('}'))
{ /* quick exit if '}' follows ',' */
lexpush();
break;
} /* if */
tok = lex(&val, &str); /* read in (new) token */
if (tok != tSYMBOL && tok != tLABEL)
error(20, str); /* invalid symbol name */
strcpy(constname, str); /* save symbol name */
size = increment; /* default increment of 'val' */
if (tok == tLABEL || matchtoken(':'))
constexpr(&size, NULL); /* get size */
if (matchtoken('='))
constexpr(&value, NULL); /* get value */
/* add_constant() checks whether a variable (global or local) or
* a constant with the same name already exists */
add_constant(constname, value, vclass, tag);
if (multiplier == 1)
value += size;
else
value *= size * multiplier;
}
while (matchtoken(','));
needtoken('}'); /* terminates the constant list */
matchtoken(';'); /* eat an optional ; */
/* set the enum name to the last value plus one */
if (enumname[0] != '\0')
add_constant(enumname, value, vclass, tag);
}
/*
* Finds a function in the global symbol table or creates a new entry.
* It does some basic processing and error checking.
*/
symbol *
fetchfunc(char *name, int tag)
{
symbol *sym;
cell offset;
offset = code_idx;
if ((sc_debug & sSYMBOLIC) != 0)
{
offset += opcodes(1) + opargs(3) + nameincells(name);
/* ^^^ The address for the symbol is the code address. But the
* "symbol" instruction itself generates code. Therefore the
* offset is pre-adjusted to the value it will have after the
* symbol instruction.
*/
} /* if */
if ((sym = findglb(name)))
{ /* already in symbol table? */
if (sym->ident != iFUNCTN)
{
error(21, name); /* yes, but not as a function */
return NULL; /* make sure the old symbol is not damaged */
}
else if ((sym->usage & uDEFINE) != 0)
{
error(21, name); /* yes, and it's already defined */
}
else if ((sym->usage & uNATIVE) != 0)
{
error(21, name); /* yes, and it is an native */
} /* if */
assert(sym->vclass == sGLOBAL);
if ((sym->usage & uDEFINE) == 0)
{
/* as long as the function stays undefined, update the address
* and the tag */
sym->addr = offset;
sym->tag = tag;
} /* if */
}
else
{
/* don't set the "uDEFINE" flag; it may be a prototype */
sym = addsym(name, offset, iFUNCTN, sGLOBAL, tag, 0);
/* assume no arguments */
sym->dim.arglist = (arginfo *) malloc(1 * sizeof(arginfo));
sym->dim.arglist[0].ident = 0;
/* set library ID to NULL (only for native functions) */
sym->x.lib = NULL;
} /* if */
return sym;
}
/* This routine adds symbolic information for each argument.
*/
static void
define_args(void)
{
symbol *sym;
/* At this point, no local variables have been declared. All
* local symbols are function arguments.
*/
sym = loctab.next;
while (sym)
{
assert(sym->ident != iLABEL);
assert(sym->vclass == sLOCAL);
defsymbol(sym->name, sym->ident, sLOCAL, sym->addr, sym->tag);
if (sym->ident == iREFARRAY)
{
symbol *sub = sym;
while (sub)
{
symbolrange(sub->dim.array.level, sub->dim.array.length);
sub = finddepend(sub);
} /* while */
} /* if */
sym = sym->next;
} /* while */
}
static int
operatorname(char *name)
{
int opertok;
char *str;
cell val;
assert(name != NULL);
/* check the operator */
opertok = lex(&val, &str);
switch (opertok)
{
case '+':
case '-':
case '*':
case '/':
case '%':
case '>':
case '<':
case '!':
case '~':
case '=':
name[0] = (char)opertok;
name[1] = '\0';
break;
case tINC:
strcpy(name, "++");
break;
case tDEC:
strcpy(name, "--");
break;
case tlEQ:
strcpy(name, "==");
break;
case tlNE:
strcpy(name, "!=");
break;
case tlLE:
strcpy(name, "<=");
break;
case tlGE:
strcpy(name, ">=");
break;
default:
name[0] = '\0';
error(61); /* operator cannot be redefined
* (or bad operator name) */
return 0;
} /* switch */
return opertok;
}
static int
operatoradjust(int opertok, symbol * sym, char *opername, int resulttag)
{
int tags[2] = { 0, 0 };
int count = 0;
arginfo *arg;
char tmpname[sNAMEMAX + 1];
symbol *oldsym;
if (opertok == 0)
return TRUE;
/* count arguments and save (first two) tags */
while (arg = &sym->dim.arglist[count], arg->ident != 0)
{
if (count < 2)
{
if (arg->numtags > 1)
error(65, count + 1); /* function argument may only have
* a single tag */
else if (arg->numtags == 1)
tags[count] = arg->tags[0];
} /* if */
if (opertok == '~' && count == 0)
{
if (arg->ident != iREFARRAY)
error(73, arg->name); /* must be an array argument */
}
else
{
if (arg->ident != iVARIABLE)
error(66, arg->name); /* must be non-reference argument */
} /* if */
if (arg->hasdefault)
error(59, arg->name); /* arguments of an operator may not
* have a default value */
count++;
} /* while */
/* for '!', '++' and '--', count must be 1
* for '-', count may be 1 or 2
* for '=', count must be 1, and the resulttag is also important
* for all other (binary) operators and the special '~'
* operator, count must be 2
*/
switch (opertok)
{
case '!':
case '=':
case tINC:
case tDEC:
if (count != 1)
error(62); /* number or placement of the operands does
* not fit the operator */
break;
case '-':
if (count != 1 && count != 2)
error(62); /* number or placement of the operands does
* not fit the operator */
break;
default:
if (count != 2)
error(62); /* number or placement of the operands does
* not fit the operator */
} /* switch */
if (tags[0] == 0
&& ((opertok != '=' && tags[1] == 0) || (opertok == '=' && resulttag == 0)))
error(64); /* cannot change predefined operators */
/* change the operator name */
assert(opername[0] != '\0');
operator_symname(tmpname, opername, tags[0], tags[1], count, resulttag);
if ((oldsym = findglb(tmpname)))
{
int i;
if ((oldsym->usage & uDEFINE) != 0)
{
char errname[2 * sNAMEMAX + 16];
funcdisplayname(errname, tmpname);
error(21, errname); /* symbol already defined */
} /* if */
sym->usage |= oldsym->usage; /* copy flags from the previous
* definition */
for (i = 0; i < oldsym->numrefers; i++)
if (oldsym->refer[i])
refer_symbol(sym, oldsym->refer[i]);
delete_symbol(&glbtab, oldsym);
} /* if */
if ((sc_debug & sSYMBOLIC) != 0)
sym->addr += nameincells(tmpname) - nameincells(sym->name);
strcpy(sym->name, tmpname);
sym->hash = namehash(sym->name); /* calculate new hash */
/* operators should return a value, except the '~' operator */
if (opertok != '~')
sym->usage |= uRETVALUE;
return TRUE;
}
static int
check_operatortag(int opertok, int resulttag, char *opername)
{
assert(opername != NULL && opername[0] != '\0');
switch (opertok)
{
case '!':
case '<':
case '>':
case tlEQ:
case tlNE:
case tlLE:
case tlGE:
if (resulttag != sc_addtag("bool"))
{
error(63, opername, "bool:"); /* operator X requires
* a "bool:" result tag */
return FALSE;
} /* if */
break;
case '~':
if (resulttag != 0)
{
error(63, opername, "_:"); /* operator "~" requires
* a "_:" result tag */
return FALSE;
} /* if */
break;
} /* switch */
return TRUE;
}
static char *
tag2str(char *dest, int tag)
{
tag &= TAGMASK;
assert(tag >= 0);
sprintf(dest, "0%x", tag);
return sc_isdigit(dest[1]) ? &dest[1] : dest;
}
char *
operator_symname(char *symname, char *opername, int tag1, int tag2,
int numtags, int resulttag)
{
char tagstr1[10], tagstr2[10];
int opertok;
assert(numtags >= 1 && numtags <= 2);
opertok = (opername[1] == '\0') ? opername[0] : 0;
if (opertok == '=')
sprintf(symname, "%s%s%s", tag2str(tagstr1, resulttag), opername,
tag2str(tagstr2, tag1));
else if (numtags == 1 || opertok == '~')
sprintf(symname, "%s%s", opername, tag2str(tagstr1, tag1));
else
sprintf(symname, "%s%s%s", tag2str(tagstr1, tag1), opername,
tag2str(tagstr2, tag2));
return symname;
}
static int
parse_funcname(char *fname, int *tag1, int *tag2, char *opname)
{
char *ptr, *name;
int unary;
/* tags are only positive, so if the function name starts with a '-',
* the operator is an unary '-' or '--' operator.
*/
if (*fname == '-')
{
*tag1 = 0;
unary = TRUE;
ptr = fname;
}
else
{
*tag1 = (int)strtol(fname, &ptr, 16);
unary = ptr == fname; /* unary operator if it doesn't start
* with a tag name */
} /* if */
assert(!unary || *tag1 == 0);
assert(*ptr != '\0');
for (name = opname; !sc_isdigit(*ptr);)
*name++ = *ptr++;
*name = '\0';
*tag2 = (int)strtol(ptr, NULL, 16);
return unary;
}
char *
funcdisplayname(char *dest, char *funcname)
{
int tags[2];
char opname[10];
constvalue *tagsym[2];
int unary;
if (sc_isalpha(*funcname) || *funcname == '_' || *funcname == PUBLIC_CHAR
|| *funcname == '\0')
{
if (dest != funcname)
strcpy(dest, funcname);
return dest;
} /* if */
unary = parse_funcname(funcname, &tags[0], &tags[1], opname);
tagsym[1] = find_constval_byval(&tagname_tab, tags[1]);
assert(tagsym[1] != NULL);
if (unary)
{
sprintf(dest, "operator%s(%s:)", opname, tagsym[1]->name);
}
else
{
tagsym[0] = find_constval_byval(&tagname_tab, tags[0]);
/* special case: the assignment operator has the return value
* as the 2nd tag */
if (opname[0] == '=' && opname[1] == '\0')
sprintf(dest, "%s:operator%s(%s:)", tagsym[0]->name, opname,
tagsym[1]->name);
else
sprintf(dest, "operator%s(%s:,%s:)", opname, tagsym[0]->name,
tagsym[1]->name);
} /* if */
return dest;
}
static void
funcstub(int native)
{
int tok, tag;
char *str;
cell val;
char symbolname[sNAMEMAX + 1];
symbol *sym;
int opertok;
opertok = 0;
lastst = 0;
litidx = 0; /* clear the literal pool */
tag = sc_addtag(NULL);
tok = lex(&val, &str);
if (native)
{
if (tok == tPUBLIC || tok == tSTOCK || tok == tSTATIC ||
(tok == tSYMBOL && *str == PUBLIC_CHAR))
error(42); /* invalid combination of class specifiers */
}
else
{
if (tok == tPUBLIC || tok == tSTATIC)
tok = lex(&val, &str);
} /* if */
if (tok == tOPERATOR)
{
opertok = operatorname(symbolname);
if (opertok == 0)
return; /* error message already given */
check_operatortag(opertok, tag, symbolname);
}
else
{
if (tok != tSYMBOL && freading)
{
error(10); /* illegal function or declaration */
return;
} /* if */
strcpy(symbolname, str);
} /* if */
needtoken('('); /* only functions may be native/forward */
sym = fetchfunc(symbolname, tag); /* get a pointer to the
* function entry */
if (!sym)
return;
if (native)
{
sym->usage = uNATIVE | uRETVALUE | uDEFINE;
sym->x.lib = curlibrary;
} /* if */
declargs(sym);
/* "declargs()" found the ")" */
if (!operatoradjust(opertok, sym, symbolname, tag))
sym->usage &= ~uDEFINE;
/* for a native operator, also need to specify an "exported"
* function name; for a native function, this is optional
*/
if (native)
{
if (opertok != 0)
{
needtoken('=');
lexpush(); /* push back, for matchtoken() to retrieve again */
} /* if */
if (matchtoken('='))
{
/* allow number or symbol */
if (matchtoken(tSYMBOL))
{
tokeninfo(&val, &str);
if (strlen(str) > sEXPMAX)
{
error(220, str, sEXPMAX);
str[sEXPMAX] = '\0';
} /* if */
insert_alias(sym->name, str);
}
else
{
constexpr(&val, NULL);
sym->addr = val;
/*
* ?? Must mark this address, so that it won't be generated again
* and it won't be written to the output file. At the moment,
* I have assumed that this syntax is only valid if val < 0.
* To properly mix "normal" native functions and indexed native
* functions, one should use negative indices anyway.
* Special code for a negative index in sym->addr exists in
* SC4.C (ffcall()) and in SC6.C (the loops for counting the
* number of native variables and for writing them).
*/
} /* if */
} /* if */
} /* if */
needtoken(tTERM);
litidx = 0; /* clear the literal pool */
/* clear local variables queue */
delete_symbols(&loctab, 0, TRUE, TRUE);
}
/* newfunc - begin a function
*
* This routine is called from "parse" and tries to make a function
* out of the following text
*
* Global references: funcstatus,lastst,litidx
* rettype (altered)
* curfunc (altered)
* declared (altered)
* glb_declared (altered)
* sc_alignnext (altered)
*/
static int
newfunc(char *firstname, int firsttag, int fpublic, int fstatic, int stock)
{
symbol *sym;
int argcnt, tok, tag, funcline;
int opertok, opererror;
char symbolname[sNAMEMAX + 1];
char *str;
cell val, cidx, glbdecl;
int filenum;
litidx = 0; /* clear the literal pool ??? */
opertok = 0;
lastst = 0; /* no statement yet */
cidx = 0; /* just to avoid compiler warnings */
glbdecl = 0;
filenum = fcurrent; /* save file number at start of declaration */
if (firstname)
{
assert(strlen(firstname) <= sNAMEMAX);
strcpy(symbolname, firstname); /* save symbol name */
tag = firsttag;
}
else
{
tag = (firsttag >= 0) ? firsttag : sc_addtag(NULL);
tok = lex(&val, &str);
assert(!fpublic);
if (tok == tNATIVE || (tok == tPUBLIC && stock))
error(42); /* invalid combination of class specifiers */
if (tok == tOPERATOR)
{
opertok = operatorname(symbolname);
if (opertok == 0)
return TRUE; /* error message already given */
check_operatortag(opertok, tag, symbolname);
}
else
{
if (tok != tSYMBOL && freading)
{
error(20, str); /* invalid symbol name */
return FALSE;
} /* if */
assert(strlen(str) <= sNAMEMAX);
strcpy(symbolname, str);
} /* if */
} /* if */
/* check whether this is a function or a variable declaration */
if (!matchtoken('('))
return FALSE;
/* so it is a function, proceed */
funcline = fline; /* save line at which the function is defined */
if (symbolname[0] == PUBLIC_CHAR)
{
fpublic = TRUE; /* implicitly public function */
if (stock)
error(42); /* invalid combination of class specifiers */
} /* if */
sym = fetchfunc(symbolname, tag); /* get a pointer to the
* function entry */
if (!sym)
return TRUE;
if (fpublic)
sym->usage |= uPUBLIC;
if (fstatic)
sym->fnumber = filenum;
/* declare all arguments */
argcnt = declargs(sym);
opererror = !operatoradjust(opertok, sym, symbolname, tag);
if (strcmp(symbolname, uMAINFUNC) == 0)
{
if (argcnt > 0)
error(5); /* "main()" function may not have any arguments */
sym->usage |= uREAD; /* "main()" is the program's entry point:
* always used */
} /* if */
/* "declargs()" found the ")"; if a ";" appears after this, it was a
* prototype */
if (matchtoken(';'))
{
if (!sc_needsemicolon)
error(218); /* old style prototypes used with optional
* semicolumns */
delete_symbols(&loctab, 0, TRUE, TRUE); /* prototype is done;
* forget everything */
return TRUE;
} /* if */
/* so it is not a prototype, proceed */
/* if this is a function that is not referred to (this can only be
* detected in the second stage), shut code generation off */
if (sc_status == statWRITE && (sym->usage & uREAD) == 0)
{
sc_status = statSKIP;
cidx = code_idx;
glbdecl = glb_declared;
} /* if */
begcseg();
sym->usage |= uDEFINE; /* set the definition flag */
if (fpublic)
sym->usage |= uREAD; /* public functions are always "used" */
if (stock)
sym->usage |= uSTOCK;
if (opertok != 0 && opererror)
sym->usage &= ~uDEFINE;
defsymbol(sym->name, iFUNCTN, sGLOBAL,
code_idx + opcodes(1) + opargs(3) + nameincells(sym->name), tag);
/* ^^^ The address for the symbol is the code address. But the
* "symbol" instruction itself generates code. Therefore the
* offset is pre-adjusted to the value it will have after the
* symbol instruction.
*/
startfunc(sym->name); /* creates stack frame */
if ((sc_debug & sSYMBOLIC) != 0)
setline(funcline, fcurrent);
if (sc_alignnext)
{
alignframe(sc_dataalign);
sc_alignnext = FALSE;
} /* if */
declared = 0; /* number of local cells */
rettype = (sym->usage & uRETVALUE); /* set "return type" variable */
curfunc = sym;
define_args(); /* add the symbolic info for the function arguments */
statement(NULL, FALSE);
if ((rettype & uRETVALUE) != 0)
sym->usage |= uRETVALUE;
if (declared != 0)
{
/* This happens only in a very special (and useless) case, where a
* function has only a single statement in its body (no compound
* block) and that statement declares a new variable
*/
modstk((int)declared * sizeof(cell)); /* remove all local
* variables */
declared = 0;
} /* if */
if ((lastst != tRETURN) && (lastst != tGOTO))
{
const1(0);
ffret();
if ((sym->usage & uRETVALUE) != 0)
{
char symname[2 * sNAMEMAX + 16]; /* allow space for user
* defined operators */
funcdisplayname(symname, sym->name);
error(209, symname); /* function should return a value */
} /* if */
} /* if */
endfunc();
if (litidx)
{ /* if there are literals defined */
glb_declared += litidx;
begdseg(); /* flip to DATA segment */
dumplits(); /* dump literal strings */
litidx = 0;
} /* if */
testsymbols(&loctab, 0, TRUE, TRUE); /* test for unused arguments
* and labels */
delete_symbols(&loctab, 0, TRUE, TRUE); /* clear local variables
* queue */
assert(loctab.next == NULL);
curfunc = NULL;
if (sc_status == statSKIP)
{
sc_status = statWRITE;
code_idx = cidx;
glb_declared = glbdecl;
} /* if */
return TRUE;
}
static int
argcompare(arginfo * a1, arginfo * a2)
{
int result, level;
result = strcmp(a1->name, a2->name) == 0;
if (result)
result = a1->ident == a2->ident;
if (result)
result = a1->usage == a2->usage;
if (result)
result = a1->numtags == a2->numtags;
if (result)
{
int i;
for (i = 0; i < a1->numtags && result; i++)
result = a1->tags[i] == a2->tags[i];
} /* if */
if (result)
result = a1->hasdefault == a2->hasdefault;
if (a1->hasdefault)
{
if (a1->ident == iREFARRAY)
{
if (result)
result = a1->defvalue.array.size == a2->defvalue.array.size;
if (result)
result =
a1->defvalue.array.arraysize == a2->defvalue.array.arraysize;
/* also check the dimensions of both arrays */
if (result)
result = a1->numdim == a2->numdim;
for (level = 0; result && level < a1->numdim; level++)
result = a1->dim[level] == a2->dim[level];
/* ??? should also check contents of the default array
* (these troubles go away in a 2-pass compiler that forbids
* double declarations, but Small currently does not forbid them)
*/
}
else
{
if (result)
{
if ((a1->hasdefault & uSIZEOF) != 0
|| (a1->hasdefault & uTAGOF) != 0)
result = a1->hasdefault == a2->hasdefault
&& strcmp(a1->defvalue.size.symname,
a2->defvalue.size.symname) == 0
&& a1->defvalue.size.level == a2->defvalue.size.level;
else
result = a1->defvalue.val == a2->defvalue.val;
} /* if */
} /* if */
if (result)
result = a1->defvalue_tag == a2->defvalue_tag;
} /* if */
return result;
}
/* declargs()
*
* This routine adds an entry in the local symbol table for each
* argument found in the argument list.
* It returns the number of arguments.
*/
static int
declargs(symbol * sym)
{
#define MAXTAGS 16
char *ptr;
int argcnt, oldargcnt, tok, tags[MAXTAGS], numtags;
cell val;
arginfo arg, *arglist;
char name[sNAMEMAX + 1];
int ident, fpublic, fconst;
int idx;
/* if the function is already defined earlier, get the number of
* arguments of the existing definition
*/
oldargcnt = 0;
if ((sym->usage & uPROTOTYPED) != 0)
while (sym->dim.arglist[oldargcnt].ident != 0)
oldargcnt++;
argcnt = 0; /* zero aruments up to now */
ident = iVARIABLE;
numtags = 0;
fconst = FALSE;
fpublic = (sym->usage & uPUBLIC) != 0;
/* the '(' parantheses has already been parsed */
if (!matchtoken(')'))
{
do
{ /* there are arguments; process them */
/* any legal name increases argument count (and stack offset) */
tok = lex(&val, &ptr);
switch (tok)
{
case 0:
/* nothing */
break;
case '&':
if (ident != iVARIABLE || numtags > 0)
error(1, "-identifier-", "&");
ident = iREFERENCE;
break;
case tCONST:
if (ident != iVARIABLE || numtags > 0)
error(1, "-identifier-", "const");
fconst = TRUE;
break;
case tLABEL:
if (numtags > 0)
error(1, "-identifier-", "-tagname-");
tags[0] = sc_addtag(ptr);
numtags = 1;
break;
case '{':
if (numtags > 0)
error(1, "-identifier-", "-tagname-");
numtags = 0;
while (numtags < MAXTAGS)
{
if (!matchtoken('_') && !needtoken(tSYMBOL))
break;
tokeninfo(&val, &ptr);
tags[numtags++] = sc_addtag(ptr);
if (matchtoken('}'))
break;
needtoken(',');
} /* for */
needtoken(':');
tok = tLABEL; /* for outer loop:
* flag that we have seen a tagname */
break;
case tSYMBOL:
if (argcnt >= sMAXARGS)
error(45); /* too many function arguments */
strcpy(name, ptr); /* save symbol name */
if (name[0] == PUBLIC_CHAR)
error(56, name); /* function arguments cannot be public */
if (numtags == 0)
tags[numtags++] = 0; /* default tag */
/* Stack layout:
* base + 0*sizeof(cell) == previous "base"
* base + 1*sizeof(cell) == function return address
* base + 2*sizeof(cell) == number of arguments
* base + 3*sizeof(cell) == first argument of the function
* So the offset of each argument is:
* "(argcnt+3) * sizeof(cell)".
*/
doarg(name, ident, (argcnt + 3) * sizeof(cell), tags, numtags,
fpublic, fconst, &arg);
if (fpublic && arg.hasdefault)
error(59, name); /* arguments of a public function may not
* have a default value */
if ((sym->usage & uPROTOTYPED) == 0)
{
/* redimension the argument list, add the entry */
sym->dim.arglist =
(arginfo *) realloc(sym->dim.arglist,
(argcnt + 2) * sizeof(arginfo));
if (!sym->dim.arglist)
error(103); /* insufficient memory */
sym->dim.arglist[argcnt] = arg;
sym->dim.arglist[argcnt + 1].ident = 0; /* keep the list
* terminated */
}
else
{
/* check the argument with the earlier definition */
if (argcnt > oldargcnt
|| !argcompare(&sym->dim.arglist[argcnt], &arg))
error(25); /* function definition does not match prototype */
/* may need to free default array argument and the tag list */
if (arg.ident == iREFARRAY && arg.hasdefault)
free(arg.defvalue.array.data);
else if (arg.ident == iVARIABLE
&& ((arg.hasdefault & uSIZEOF) != 0
|| (arg.hasdefault & uTAGOF) != 0))
free(arg.defvalue.size.symname);
free(arg.tags);
} /* if */
argcnt++;
ident = iVARIABLE;
numtags = 0;
fconst = FALSE;
break;
case tELLIPS:
if (ident != iVARIABLE)
error(10); /* illegal function or declaration */
if (numtags == 0)
tags[numtags++] = 0; /* default tag */
if ((sym->usage & uPROTOTYPED) == 0)
{
/* redimension the argument list, add the entry iVARARGS */
sym->dim.arglist =
(arginfo *) realloc(sym->dim.arglist,
(argcnt + 2) * sizeof(arginfo));
if (!sym->dim.arglist)
error(103); /* insufficient memory */
sym->dim.arglist[argcnt + 1].ident = 0; /* keep the list
* terminated */
sym->dim.arglist[argcnt].ident = iVARARGS;
sym->dim.arglist[argcnt].hasdefault = FALSE;
sym->dim.arglist[argcnt].defvalue.val = 0;
sym->dim.arglist[argcnt].defvalue_tag = 0;
sym->dim.arglist[argcnt].numtags = numtags;
sym->dim.arglist[argcnt].tags =
(int *)malloc(numtags * sizeof tags[0]);
if (!sym->dim.arglist[argcnt].tags)
error(103); /* insufficient memory */
memcpy(sym->dim.arglist[argcnt].tags, tags,
numtags * sizeof tags[0]);
}
else
{
if (argcnt > oldargcnt
|| sym->dim.arglist[argcnt].ident != iVARARGS)
error(25); /* function definition does not match prototype */
} /* if */
argcnt++;
break;
default:
error(10); /* illegal function or declaration */
} /* switch */
}
while (tok == '&' || tok == tLABEL || tok == tCONST || (tok != tELLIPS && matchtoken(','))); /* more? */
/* if the next token is not ",", it should be ")" */
needtoken(')');
} /* if */
/* resolve any "sizeof" arguments (now that all arguments are known) */
assert(sym->dim.arglist != NULL);
arglist = sym->dim.arglist;
for (idx = 0; idx < argcnt && arglist[idx].ident != 0; idx++)
{
if ((arglist[idx].hasdefault & uSIZEOF) != 0
|| (arglist[idx].hasdefault & uTAGOF) != 0)
{
int altidx;
/* Find the argument with the name mentioned after the "sizeof".
* Note that we cannot use findloc here because we need the
* arginfo struct, not the symbol.
*/
ptr = arglist[idx].defvalue.size.symname;
for (altidx = 0;
altidx < argcnt && strcmp(ptr, arglist[altidx].name) != 0;
altidx++)
/* nothing */ ;
if (altidx >= argcnt)
{
error(17, ptr); /* undefined symbol */
}
else
{
/* check the level against the number of dimensions */
/* the level must be zero for "tagof" values */
assert(arglist[idx].defvalue.size.level == 0
|| (arglist[idx].hasdefault & uSIZEOF) != 0);
if (arglist[idx].defvalue.size.level > 0
&& arglist[idx].defvalue.size.level >=
arglist[altidx].numdim)
error(28); /* invalid subscript */
if (arglist[altidx].ident != iREFARRAY)
{
assert(arglist[altidx].ident == iVARIABLE
|| arglist[altidx].ident == iREFERENCE);
error(223, ptr); /* redundant sizeof */
} /* if */
} /* if */
} /* if */
} /* for */
sym->usage |= uPROTOTYPED;
errorset(sRESET); /* reset error flag (clear the "panic mode") */
return argcnt;
}
/* doarg - declare one argument type
*
* this routine is called from "declargs()" and adds an entry in the
* local symbol table for one argument. "fpublic" indicates whether
* the function for this argument list is public.
* The arguments themselves are never public.
*/
static void
doarg(char *name, int ident, int offset, int tags[], int numtags,
int fpublic, int fconst, arginfo * arg)
{
symbol *argsym;
cell size;
int idxtag[sDIMEN_MAX];
strcpy(arg->name, name);
arg->hasdefault = FALSE; /* preset (most common case) */
arg->defvalue.val = 0; /* clear */
arg->defvalue_tag = 0;
arg->numdim = 0;
if (matchtoken('['))
{
if (ident == iREFERENCE)
error(67, name); /*illegal declaration ("&name[]" is unsupported) */
do
{
if (arg->numdim == sDIMEN_MAX)
{
error(53); /* exceeding maximum number of dimensions */
return;
} /* if */
/* there is no check for non-zero major dimensions here, only if
* the array parameter has a default value, we enforce that all
* array dimensions, except the last, are non-zero
*/
size = needsub(&idxtag[arg->numdim]); /* may be zero here,
*it is a pointer anyway */
#if INT_MAX < LONG_MAX
if (size > INT_MAX)
error(105); /* overflow, exceeding capacity */
#endif
arg->dim[arg->numdim] = (int)size;
arg->numdim += 1;
}
while (matchtoken('['));
ident = iREFARRAY; /* "reference to array" (is a pointer) */
if (matchtoken('='))
{
int level;
lexpush(); /* initials() needs the "=" token again */
assert(numtags > 0);
/* for the moment, when a default value is given for the array,
* all dimension sizes, except the last, must be non-zero
* (function initials() requires to know the major dimensions)
*/
for (level = 0; level < arg->numdim - 1; level++)
if (arg->dim[level] == 0)
error(52); /* only last dimension may be variable length */
initials(ident, tags[0], &size, arg->dim, arg->numdim);
assert(size >= litidx);
/* allocate memory to hold the initial values */
arg->defvalue.array.data = (cell *) malloc(litidx * sizeof(cell));
if (arg->defvalue.array.data)
{
int i;
memcpy(arg->defvalue.array.data, litq, litidx * sizeof(cell));
arg->hasdefault = TRUE; /* argument has default value */
arg->defvalue.array.size = litidx;
arg->defvalue.array.addr = -1;
/* calculate size to reserve on the heap */
arg->defvalue.array.arraysize = 1;
for (i = 0; i < arg->numdim; i++)
arg->defvalue.array.arraysize *= arg->dim[i];
if (arg->defvalue.array.arraysize < arg->defvalue.array.size)
arg->defvalue.array.arraysize = arg->defvalue.array.size;
} /* if */
litidx = 0; /* reset */
} /* if */
}
else
{
if (matchtoken('='))
{
unsigned char size_tag_token;
assert(ident == iVARIABLE || ident == iREFERENCE);
arg->hasdefault = TRUE; /* argument has a default value */
size_tag_token =
(unsigned char)(matchtoken(tSIZEOF) ? uSIZEOF : 0);
if (size_tag_token == 0)
size_tag_token =
(unsigned char)(matchtoken(tTAGOF) ? uTAGOF : 0);
if (size_tag_token != 0)
{
int paranthese;
if (ident == iREFERENCE)
error(66, name); /* argument may not be a reference */
paranthese = 0;
while (matchtoken('('))
paranthese++;
if (needtoken(tSYMBOL))
{
/* save the name of the argument whose size id to take */
char *name;
cell val;
tokeninfo(&val, &name);
if (!(arg->defvalue.size.symname = strdup(name)))
error(103); /* insufficient memory */
arg->defvalue.size.level = 0;
if (size_tag_token == uSIZEOF)
{
while (matchtoken('['))
{
arg->defvalue.size.level += (short)1;
needtoken(']');
} /* while */
} /* if */
if (ident == iVARIABLE) /* make sure we set this only if
* not a reference */
arg->hasdefault |= size_tag_token; /* uSIZEOF or uTAGOF */
} /* if */
while (paranthese--)
needtoken(')');
}
else
{
constexpr(&arg->defvalue.val, &arg->defvalue_tag);
assert(numtags > 0);
if (!matchtag(tags[0], arg->defvalue_tag, TRUE))
error(213); /* tagname mismatch */
} /* if */
} /* if */
} /* if */
arg->ident = (char)ident;
arg->usage = (char)(fconst ? uCONST : 0);
arg->numtags = numtags;
arg->tags = (int *)malloc(numtags * sizeof tags[0]);
if (!arg->tags)
error(103); /* insufficient memory */
memcpy(arg->tags, tags, numtags * sizeof tags[0]);
argsym = findloc(name);
if (argsym)
{
error(21, name); /* symbol already defined */
}
else
{
if ((argsym = findglb(name)) && argsym->ident != iFUNCTN)
error(219, name); /* variable shadows another symbol */
/* add details of type and address */
assert(numtags > 0);
argsym = addvariable(name, offset, ident, sLOCAL, tags[0],
arg->dim, arg->numdim, idxtag);
argsym->compound = 0;
if (ident == iREFERENCE)
argsym->usage |= uREAD; /* because references are passed back */
if (fpublic)
argsym->usage |= uREAD; /* arguments of public functions
* are always "used" */
if (fconst)
argsym->usage |= uCONST;
} /* if */
}
static int
count_referrers(symbol * entry)
{
int i, count;
count = 0;
for (i = 0; i < entry->numrefers; i++)
if (entry->refer[i])
count++;
return count;
}
/* Every symbol has a referrer list, that contains the functions that
* use the symbol. Now, if function "apple" is accessed by functions
* "banana" and "citron", but neither function "banana" nor "citron" are
* used by anyone else, then, by inference, function "apple" is not used
* either. */
static void
reduce_referrers(symbol * root)
{
int i, restart;
symbol *sym, *ref;
do
{
restart = 0;
for (sym = root->next; sym; sym = sym->next)
{
if (sym->parent)
continue; /* hierarchical data type */
if (sym->ident == iFUNCTN
&& (sym->usage & uNATIVE) == 0
&& (sym->usage & uPUBLIC) == 0
&& strcmp(sym->name, uMAINFUNC) != 0
&& count_referrers(sym) == 0)
{
sym->usage &= ~(uREAD | uWRITTEN); /* erase usage bits if
* there is no referrer */
/* find all symbols that are referred by this symbol */
for (ref = root->next; ref; ref = ref->next)
{
if (ref->parent)
continue; /* hierarchical data type */
assert(ref->refer != NULL);
for (i = 0; i < ref->numrefers && ref->refer[i] != sym;
i++)
/* nothing */ ;
if (i < ref->numrefers)
{
assert(ref->refer[i] == sym);
ref->refer[i] = NULL;
restart++;
} /* if */
} /* for */
}
else if ((sym->ident == iVARIABLE || sym->ident == iARRAY)
&& (sym->usage & uPUBLIC) == 0
&& !sym->parent && count_referrers(sym) == 0)
{
sym->usage &= ~(uREAD | uWRITTEN); /* erase usage bits if
* there is no referrer */
} /* if */
} /* for */
/* after removing a symbol, check whether more can be removed */
}
while (restart > 0);
}
/* testsymbols - test for unused local or global variables
*
* "Public" functions are excluded from the check, since these
* may be exported to other object modules.
* Labels are excluded from the check if the argument 'testlabs'
* is 0. Thus, labels are not tested until the end of the function.
* Constants may also be excluded (convenient for global constants).
*
* When the nesting level drops below "level", the check stops.
*
* The function returns whether there is an "entry" point for the file.
* This flag will only be 1 when browsing the global symbol table.
*/
static int
testsymbols(symbol * root, int level, int testlabs, int testconst)
{
char symname[2 * sNAMEMAX + 16];
int entry = FALSE;
symbol *sym = root->next;
while (sym && sym->compound >= level)
{
switch (sym->ident)
{
case iLABEL:
if (testlabs)
{
if ((sym->usage & uDEFINE) == 0)
error(19, sym->name); /* not a label: ... */
else if ((sym->usage & uREAD) == 0)
error(203, sym->name); /* symbol isn't used: ... */
} /* if */
break;
case iFUNCTN:
if ((sym->usage & (uDEFINE | uREAD | uNATIVE | uSTOCK)) == uDEFINE)
{
funcdisplayname(symname, sym->name);
if (symname[0] != '\0')
error(203, symname); /* symbol isn't used ...
* (and not native/stock) */
} /* if */
if ((sym->usage & uPUBLIC) != 0
|| strcmp(sym->name, uMAINFUNC) == 0)
entry = TRUE; /* there is an entry point */
break;
case iCONSTEXPR:
if (testconst && (sym->usage & uREAD) == 0)
error(203, sym->name); /* symbol isn't used: ... */
break;
default:
/* a variable */
if (sym->parent)
break; /* hierarchical data type */
if ((sym->usage & (uWRITTEN | uREAD | uSTOCK | uPUBLIC)) == 0)
error(203, sym->name); /* symbol isn't used (and not stock
* or public) */
else if ((sym->usage & (uREAD | uSTOCK | uPUBLIC)) == 0)
error(204, sym->name); /* value assigned to symbol is
* never used */
#if 0 /*// ??? not sure whether it is a good idea to
* force people use "const" */
else if ((sym->usage & (uWRITTEN | uPUBLIC | uCONST)) == 0
&& sym->ident == iREFARRAY)
error(214, sym->name); /* make array argument "const" */
#endif
} /* if */
sym = sym->next;
} /* while */
return entry;
}
static cell
calc_array_datasize(symbol * sym, cell * offset)
{
cell length;
assert(sym != NULL);
assert(sym->ident == iARRAY || sym->ident == iREFARRAY);
length = sym->dim.array.length;
if (sym->dim.array.level > 0)
{
cell sublength =
calc_array_datasize(finddepend(sym), offset);
if (offset)
*offset = length * (*offset + sizeof(cell));
if (sublength > 0)
length *= length * sublength;
else
length = 0;
}
else
{
if (offset)
*offset = 0;
} /* if */
return length;
}
static void
destructsymbols(symbol * root, int level)
{
cell offset = 0;
int savepri = FALSE;
symbol *sym = root->next;
while (sym && sym->compound >= level)
{
if (sym->ident == iVARIABLE || sym->ident == iARRAY)
{
char symbolname[16];
symbol *opsym;
cell elements;
/* check that the '~' operator is defined for this tag */
operator_symname(symbolname, "~", sym->tag, 0, 1, 0);
if ((opsym = findglb(symbolname)))
{
/* save PRI, in case of a return statement */
if (!savepri)
{
push1(); /* right-hand operand is in PRI */
savepri = TRUE;
} /* if */
/* if the variable is an array, get the number of elements */
if (sym->ident == iARRAY)
{
elements = calc_array_datasize(sym, &offset);
/* "elements" can be zero when the variable is declared like
* new mytag: myvar[2][] = { {1, 2}, {3, 4} }
* one should declare all dimensions!
*/
if (elements == 0)
error(46, sym->name); /* array size is unknown */
}
else
{
elements = 1;
offset = 0;
} /* if */
pushval(elements);
/* call the '~' operator */
address(sym);
addconst(offset); /*add offset to array data to the address */
push1();
pushval(2 * sizeof(cell)); /* 2 parameters */
ffcall(opsym, 1);
if (sc_status != statSKIP)
markusage(opsym, uREAD); /* do not mark as "used" when this
* call itself is skipped */
if (opsym->x.lib)
opsym->x.lib->value += 1; /* increment "usage count"
* of the library */
} /* if */
} /* if */
sym = sym->next;
} /* while */
/* restore PRI, if it was saved */
if (savepri)
pop1();
}
static constvalue *
insert_constval(constvalue * prev, constvalue * next, char *name,
cell val, short idx)
{
constvalue *cur;
if (!(cur = (constvalue *)malloc(sizeof(constvalue))))
error(103); /* insufficient memory (fatal error) */
memset(cur, 0, sizeof(constvalue));
strcpy(cur->name, name);
cur->value = val;
cur->index = idx;
cur->next = next;
prev->next = cur;
return cur;
}
constvalue *
append_constval(constvalue * table, char *name, cell val, short idx)
{
constvalue *cur, *prev;
/* find the end of the constant table */
for (prev = table, cur = table->next; cur;
prev = cur, cur = cur->next)
/* nothing */ ;
return insert_constval(prev, NULL, name, val, idx);
}
constvalue *
find_constval(constvalue * table, char *name, short idx)
{
constvalue *ptr = table->next;
while (ptr)
{
if (strcmp(name, ptr->name) == 0 && ptr->index == idx)
return ptr;
ptr = ptr->next;
} /* while */
return NULL;
}
static constvalue *
find_constval_byval(constvalue * table, cell val)
{
constvalue *ptr = table->next;
while (ptr)
{
if (ptr->value == val)
return ptr;
ptr = ptr->next;
} /* while */
return NULL;
}
#if 0 /* never used */
static int
delete_constval(constvalue * table, char *name)
{
constvalue *prev = table;
constvalue *cur = prev->next;
while (cur != NULL)
{
if (strcmp(name, cur->name) == 0)
{
prev->next = cur->next;
free(cur);
return TRUE;
} /* if */
prev = cur;
cur = cur->next;
} /* while */
return FALSE;
}
#endif
void
delete_consttable(constvalue * table)
{
constvalue *cur = table->next, *next;
while (cur)
{
next = cur->next;
free(cur);
cur = next;
} /* while */
memset(table, 0, sizeof(constvalue));
}
/* add_constant
*
* Adds a symbol to the #define symbol table.
*/
void
add_constant(char *name, cell val, int vclass, int tag)
{
symbol *sym;
/* Test whether a global or local symbol with the same name exists. Since
* constants are stored in the symbols table, this also finds previously
* defind constants. */
sym = findglb(name);
if (!sym)
sym = findloc(name);
if (sym)
{
/* silently ignore redefinitions of constants with the same value */
if (sym->ident == iCONSTEXPR)
{
if (sym->addr != val)
error(201, name); /* redefinition of constant (different value) */
}
else
{
error(21, name); /* symbol already defined */
} /* if */
return;
} /* if */
/* constant doesn't exist yet, an entry must be created */
sym = addsym(name, val, iCONSTEXPR, vclass, tag, uDEFINE);
if (sc_status == statIDLE)
sym->usage |= uPREDEF;
}
/* statement - The Statement Parser
*
* This routine is called whenever the parser needs to know what
* statement it encounters (i.e. whenever program syntax requires a
* statement).
*/
static void
statement(int *lastindent, int allow_decl)
{
int tok;
cell val;
char *st;
if (!freading)
{
error(36); /* empty statement */
return;
} /* if */
errorset(sRESET);
tok = lex(&val, &st);
if (tok != '{')
setline(fline, fcurrent);
/* lex() has set stmtindent */
if (lastindent && tok != tLABEL)
{
#if 0
if (*lastindent >= 0 && *lastindent != stmtindent &&
!indent_nowarn && sc_tabsize > 0)
error(217); /* loose indentation */
#endif
*lastindent = stmtindent;
indent_nowarn = TRUE; /* if warning was blocked, re-enable it */
} /* if */
switch (tok)
{
case 0:
/* nothing */
break;
case tNEW:
if (allow_decl)
{
declloc(FALSE);
lastst = tNEW;
}
else
{
error(3); /* declaration only valid in a block */
} /* if */
break;
case tSTATIC:
if (allow_decl)
{
declloc(TRUE);
lastst = tNEW;
}
else
{
error(3); /* declaration only valid in a block */
} /* if */
break;
case '{':
if (!matchtoken('}')) /* {} is the empty statement */
compound();
/* lastst (for "last statement") does not change */
break;
case ';':
error(36); /* empty statement */
break;
case tIF:
doif();
lastst = tIF;
break;
case tWHILE:
dowhile();
lastst = tWHILE;
break;
case tDO:
dodo();
lastst = tDO;
break;
case tFOR:
dofor();
lastst = tFOR;
break;
case tSWITCH:
doswitch();
lastst = tSWITCH;
break;
case tCASE:
case tDEFAULT:
error(14); /* not in switch */
break;
case tGOTO:
dogoto();
lastst = tGOTO;
break;
case tLABEL:
dolabel();
lastst = tLABEL;
break;
case tRETURN:
doreturn();
lastst = tRETURN;
break;
case tBREAK:
dobreak();
lastst = tBREAK;
break;
case tCONTINUE:
docont();
lastst = tCONTINUE;
break;
case tEXIT:
doexit();
lastst = tEXIT;
break;
case tASSERT:
doassert();
lastst = tASSERT;
break;
case tSLEEP:
dosleep();
lastst = tSLEEP;
break;
case tCONST:
decl_const(sLOCAL);
break;
case tENUM:
decl_enum(sLOCAL);
break;
default: /* non-empty expression */
lexpush(); /* analyze token later */
doexpr(TRUE, TRUE, TRUE, TRUE, NULL, FALSE);
needtoken(tTERM);
lastst = tEXPR;
} /* switch */
}
static void
compound(void)
{
int indent = -1;
cell save_decl = declared;
int count_stmt = 0;
nestlevel += 1; /* increase compound statement level */
while (matchtoken('}') == 0)
{ /* repeat until compound statement is closed */
if (!freading)
{
needtoken('}'); /* gives error: "expected token }" */
break;
}
else
{
if (count_stmt > 0
&& (lastst == tRETURN || lastst == tBREAK
|| lastst == tCONTINUE))
error(225); /* unreachable code */
statement(&indent, TRUE); /* do a statement */
count_stmt++;
} /* if */
} /* while */
if (lastst != tRETURN)
destructsymbols(&loctab, nestlevel);
if (lastst != tRETURN && lastst != tGOTO)
/* delete local variable space */
modstk((int)(declared - save_decl) * sizeof(cell));
testsymbols(&loctab, nestlevel, FALSE, TRUE); /* look for unused
* block locals */
declared = save_decl;
delete_symbols(&loctab, nestlevel, FALSE, TRUE);
/* erase local symbols, but
* retain block local labels
* (within the function) */
nestlevel -= 1; /* decrease compound statement level */
}
/* doexpr
*
* Global references: stgidx (referred to only)
*/
static void
doexpr(int comma, int chkeffect, int allowarray, int mark_endexpr,
int *tag, int chkfuncresult)
{
int constant, idx, ident;
int localstaging = FALSE;
cell val;
if (!staging)
{
stgset(TRUE); /* start stage-buffering */
localstaging = TRUE;
assert(stgidx == 0);
} /* if */
idx = stgidx;
errorset(sEXPRMARK);
do
{
/* on second round through, mark the end of the previous expression */
if (idx != stgidx)
endexpr(TRUE);
sideeffect = FALSE;
ident = expression(&constant, &val, tag, chkfuncresult);
if (!allowarray && (ident == iARRAY || ident == iREFARRAY))
error(33, "-unknown-"); /* array must be indexed */
if (chkeffect && !sideeffect)
error(215); /* expression has no effect */
}
while (comma && matchtoken(',')); /* more? */
if (mark_endexpr)
endexpr(TRUE); /* optionally, mark the end of the expression */
errorset(sEXPRRELEASE);
if (localstaging)
{
stgout(idx);
stgset(FALSE); /* stop staging */
} /* if */
}
/* constexpr
*/
int
constexpr(cell * val, int *tag)
{
int constant, idx;
cell cidx;
stgset(TRUE); /* start stage-buffering */
stgget(&idx, &cidx); /* mark position in code generator */
errorset(sEXPRMARK);
expression(&constant, val, tag, FALSE);
stgdel(idx, cidx); /* scratch generated code */
stgset(FALSE); /* stop stage-buffering */
if (constant == 0)
error(8); /* must be constant expression */
errorset(sEXPRRELEASE);
return constant;
}
/* test
*
* In the case a "simple assignment" operator ("=") is used within a
* test, * the warning "possibly unintended assignment" is displayed.
* This routine sets the global variable "intest" to true, it is
* restored upon termination. In the case the assignment was intended,
* use parantheses around the expression to avoid the warning;
* primary() sets "intest" to 0.
*
* Global references: intest (altered, but restored upon termination)
*/
static void
test(int label, int parens, int invert)
{
int idx, tok;
cell cidx;
value lval = { NULL, 0, 0, 0, 0, NULL };
int localstaging = FALSE;
if (!staging)
{
stgset(TRUE); /* start staging */
localstaging = TRUE;
#if !defined NDEBUG
stgget(&idx, &cidx); /* should start at zero if started
* locally */
assert(idx == 0);
#endif
} /* if */
pushstk((stkitem) intest);
intest = 1;
if (parens)
needtoken('(');
do
{
stgget(&idx, &cidx); /* mark position (of last expression) in
* code generator */
if (hier14(&lval))
rvalue(&lval);
tok = matchtoken(',');
if (tok)
endexpr(TRUE);
}
while (tok); /* do */
if (parens)
needtoken(')');
if (lval.ident == iARRAY || lval.ident == iREFARRAY)
{
char *ptr =
(lval.sym->name) ? lval.sym->name : "-unknown-";
error(33, ptr); /* array must be indexed */
} /* if */
if (lval.ident == iCONSTEXPR)
{ /* constant expression */
intest = (int)(long)popstk(); /* restore stack */
stgdel(idx, cidx);
if (lval.constval)
{ /* code always executed */
error(206); /* redundant test: always non-zero */
}
else
{
error(205); /* redundant code: never executed */
jumplabel(label);
} /* if */
if (localstaging)
{
stgout(0); /* write "jumplabel" code */
stgset(FALSE); /* stop staging */
} /* if */
return;
} /* if */
if (lval.tag != 0 && lval.tag != sc_addtag("bool"))
if (check_userop(lneg, lval.tag, 0, 1, NULL, &lval.tag))
invert = !invert; /* user-defined ! operator inverted result */
if (invert)
jmp_ne0(label); /* jump to label if true (different from 0) */
else
jmp_eq0(label); /* jump to label if false (equal to 0) */
endexpr(TRUE); /* end expression (give optimizer a chance) */
intest = (int)(long)popstk(); /* double typecast to avoid warning
* with Microsoft C */
if (localstaging)
{
stgout(0); /* output queue from the very beginning (see
* assert() when localstaging is set to TRUE) */
stgset(FALSE); /* stop staging */
} /* if */
}
static void
doif(void)
{
int flab1, flab2;
int ifindent;
ifindent = stmtindent; /* save the indent of the "if" instruction */
flab1 = getlabel(); /* get label number for false branch */
test(flab1, TRUE, FALSE); /*get expression, branch to flab1 if false */
statement(NULL, FALSE); /* if true, do a statement */
if (matchtoken(tELSE) == 0)
{ /* if...else ? */
setlabel(flab1); /* no, simple if..., print false label */
}
else
{
/* to avoid the "dangling else" error, we want a warning if the "else"
* has a lower indent than the matching "if" */
#if 0
if (stmtindent < ifindent && sc_tabsize > 0)
error(217); /* loose indentation */
#endif
flab2 = getlabel();
if ((lastst != tRETURN) && (lastst != tGOTO))
jumplabel(flab2);
setlabel(flab1); /* print false label */
statement(NULL, FALSE); /* do "else" clause */
setlabel(flab2); /* print true label */
} /* endif */
}
static void
dowhile(void)
{
int wq[wqSIZE]; /* allocate local queue */
addwhile(wq); /* add entry to queue for "break" */
setlabel(wq[wqLOOP]); /* loop label */
/* The debugger uses the "line" opcode to be able to "break" out of
* a loop. To make sure that each loop has a line opcode, even for the
* tiniest loop, set it below the top of the loop */
setline(fline, fcurrent);
test(wq[wqEXIT], TRUE, FALSE); /* branch to wq[wqEXIT] if false */
statement(NULL, FALSE); /* if so, do a statement */
jumplabel(wq[wqLOOP]); /* and loop to "while" start */
setlabel(wq[wqEXIT]); /* exit label */
delwhile(); /* delete queue entry */
}
/*
* Note that "continue" will in this case not jump to the top of the
* loop, but to the end: just before the TRUE-or-FALSE testing code.
*/
static void
dodo(void)
{
int wq[wqSIZE], top;
addwhile(wq); /* see "dowhile" for more info */
top = getlabel(); /* make a label first */
setlabel(top); /* loop label */
statement(NULL, FALSE);
needtoken(tWHILE);
setlabel(wq[wqLOOP]); /* "continue" always jumps to WQLOOP. */
setline(fline, fcurrent);
test(wq[wqEXIT], TRUE, FALSE);
jumplabel(top);
setlabel(wq[wqEXIT]);
delwhile();
needtoken(tTERM);
}
static void
dofor(void)
{
int wq[wqSIZE], skiplab;
cell save_decl;
int save_nestlevel, idx;
int *ptr;
save_decl = declared;
save_nestlevel = nestlevel;
addwhile(wq);
skiplab = getlabel();
needtoken('(');
if (matchtoken(';') == 0)
{
/* new variable declarations are allowed here */
if (matchtoken(tNEW))
{
/* The variable in expr1 of the for loop is at a
* 'compound statement' level of it own.
*/
nestlevel++;
declloc(FALSE); /* declare local variable */
}
else
{
doexpr(TRUE, TRUE, TRUE, TRUE, NULL, FALSE); /* expression 1 */
needtoken(';');
} /* if */
} /* if */
/* Adjust the "declared" field in the "while queue", in case that
* local variables were declared in the first expression of the
* "for" loop. These are deleted in separately, so a "break" or a
* "continue" must ignore these fields.
*/
ptr = readwhile();
assert(ptr != NULL);
ptr[wqBRK] = (int)declared;
ptr[wqCONT] = (int)declared;
jumplabel(skiplab); /* skip expression 3 1st time */
setlabel(wq[wqLOOP]); /* "continue" goes to this label: expr3 */
setline(fline, fcurrent);
/* Expressions 2 and 3 are reversed in the generated code:
* expression 3 precedes expression 2.
* When parsing, the code is buffered and marks for
* the start of each expression are insterted in the buffer.
*/
assert(!staging);
stgset(TRUE); /* start staging */
assert(stgidx == 0);
idx = stgidx;
stgmark(sSTARTREORDER);
stgmark((char)(sEXPRSTART + 0)); /* mark start of 2nd expression
* in stage */
setlabel(skiplab); /*jump to this point after 1st expression */
if (matchtoken(';') == 0)
{
test(wq[wqEXIT], FALSE, FALSE); /* expression 2
*(jump to wq[wqEXIT] if false) */
needtoken(';');
} /* if */
stgmark((char)(sEXPRSTART + 1)); /* mark start of 3th expression
* in stage */
if (matchtoken(')') == 0)
{
doexpr(TRUE, TRUE, TRUE, TRUE, NULL, FALSE); /* expression 3 */
needtoken(')');
} /* if */
stgmark(sENDREORDER); /* mark end of reversed evaluation */
stgout(idx);
stgset(FALSE); /* stop staging */
statement(NULL, FALSE);
jumplabel(wq[wqLOOP]);
setlabel(wq[wqEXIT]);
delwhile();
assert(nestlevel >= save_nestlevel);
if (nestlevel > save_nestlevel)
{
/* Clean up the space and the symbol table for the local
* variable in "expr1".
*/
destructsymbols(&loctab, nestlevel);
modstk((int)(declared - save_decl) * sizeof(cell));
declared = save_decl;
delete_symbols(&loctab, nestlevel, FALSE, TRUE);
nestlevel = save_nestlevel; /* reset 'compound statement'
* nesting level */
} /* if */
}
/* The switch statement is incompatible with its C sibling:
* 1. the cases are not drop through
* 2. only one instruction may appear below each case, use a compound
* instruction to execute multiple instructions
* 3. the "case" keyword accepts a comma separated list of values to
* match, it also accepts a range using the syntax "1 .. 4"
*
* SWITCH param
* PRI = expression result
* param = table offset (code segment)
*
*/
static void
doswitch(void)
{
int lbl_table, lbl_exit, lbl_case;
int tok, swdefault, casecount;
cell val;
char *str;
constvalue caselist = { NULL, "", 0, 0 }; /*case list starts empty */
constvalue *cse, *csp;
char labelname[sNAMEMAX + 1];
needtoken('(');
doexpr(TRUE, FALSE, FALSE, TRUE, NULL, FALSE); /* evaluate
* switch expression */
needtoken(')');
/* generate the code for the switch statement, the label is the
* address of the case table (to be generated later).
*/
lbl_table = getlabel();
lbl_case = 0; /* just to avoid a compiler warning */
ffswitch(lbl_table);
needtoken('{');
lbl_exit = getlabel(); /*get label number for jumping out of switch */
swdefault = FALSE;
casecount = 0;
do
{
tok = lex(&val, &str); /* read in (new) token */
switch (tok)
{
case tCASE:
if (swdefault != FALSE)
error(15); /* "default" case must be last in switch
* statement */
lbl_case = getlabel();
sc_allowtags = FALSE; /* do not allow tagnames here */
do
{
casecount++;
/* ??? enforce/document that, in a switch, a statement cannot
* start an opening brace (marks the start of a compound
* statement) and search for the right-most colon before that
* statement.
* Now, by replacing the ':' by a special COLON token, you can
* parse all expressions until that special token.
*/
constexpr(&val, NULL);
/* Search the insertion point (the table is kept in sorted
* order, so that advanced abstract machines can sift the
* case table with a binary search). Check for duplicate
* case values at the same time.
*/
for (csp = &caselist, cse = caselist.next;
cse && cse->value < val;
csp = cse, cse = cse->next)
/* nothing */ ;
if (cse && cse->value == val)
error(40, val); /* duplicate "case" label */
/* Since the label is stored as a string in the
* "constvalue", the size of an identifier must
* be at least 8, as there are 8
* hexadecimal digits in a 32-bit number.
*/
#if sNAMEMAX < 8
#error Length of identifier (sNAMEMAX) too small.
#endif
insert_constval(csp, cse, itoh(lbl_case), val, 0);
if (matchtoken(tDBLDOT))
{
cell end;
constexpr(&end, NULL);
if (end <= val)
error(50); /* invalid range */
while (++val <= end)
{
casecount++;
/* find the new insertion point */
for (csp = &caselist, cse = caselist.next;
cse && cse->value < val;
csp = cse, cse = cse->next)
/* nothing */ ;
if (cse && cse->value == val)
error(40, val); /* duplicate "case" label */
insert_constval(csp, cse, itoh(lbl_case), val, 0);
} /* if */
} /* if */
}
while (matchtoken(','));
needtoken(':'); /* ':' ends the case */
sc_allowtags = TRUE; /* reset */
setlabel(lbl_case);
statement(NULL, FALSE);
jumplabel(lbl_exit);
break;
case tDEFAULT:
if (swdefault != FALSE)
error(16); /* multiple defaults in switch */
lbl_case = getlabel();
setlabel(lbl_case);
needtoken(':');
swdefault = TRUE;
statement(NULL, FALSE);
/* Jump to lbl_exit, even thouh this is the last clause in the
*switch, because the jump table is generated between the last
* clause of the switch and the exit label.
*/
jumplabel(lbl_exit);
break;
case '}':
/* nothing, but avoid dropping into "default" */
break;
default:
error(2);
indent_nowarn = TRUE; /* disable this check */
tok = '}'; /* break out of the loop after an error */
} /* switch */
}
while (tok != '}');
#if !defined NDEBUG
/* verify that the case table is sorted (unfortunately, duplicates can
* occur; there really shouldn't be duplicate cases, but the compiler
* may not crash or drop into an assertion for a user error). */
for (cse = caselist.next; cse && cse->next; cse = cse->next)
; /* empty. no idea whether this is correct, but we MUST NOT do
* the setlabel(lbl_table) call in the loop body. doing so breaks
* switch statements that only have one case statement following.
*/
#endif
/* generate the table here, before lbl_exit (general jump target) */
setlabel(lbl_table);
if (swdefault == FALSE)
{
/* store lbl_exit as the "none-matched" label in the switch table */
strcpy(labelname, itoh(lbl_exit));
}
else
{
/* lbl_case holds the label of the "default" clause */
strcpy(labelname, itoh(lbl_case));
} /* if */
ffcase(casecount, labelname, TRUE);
/* generate the rest of the table */
for (cse = caselist.next; cse; cse = cse->next)
ffcase(cse->value, cse->name, FALSE);
setlabel(lbl_exit);
delete_consttable(&caselist); /* clear list of case labels */
}
static void
doassert(void)
{
int flab1, idx;
cell cidx;
value lval = { NULL, 0, 0, 0, 0, NULL };
if ((sc_debug & sCHKBOUNDS) != 0)
{
flab1 = getlabel(); /* get label number for "OK" branch */
test(flab1, FALSE, TRUE); /* get expression and branch
* to flab1 if true */
setline(fline, fcurrent); /* make sure we abort on the correct
* line number */
ffabort(xASSERTION);
setlabel(flab1);
}
else
{
stgset(TRUE); /* start staging */
stgget(&idx, &cidx); /* mark position in code generator */
do
{
if (hier14(&lval))
rvalue(&lval);
stgdel(idx, cidx); /* just scrap the code */
}
while (matchtoken(','));
stgset(FALSE); /* stop staging */
} /* if */
needtoken(tTERM);
}
static void
dogoto(void)
{
char *st;
cell val;
symbol *sym;
if (lex(&val, &st) == tSYMBOL)
{
sym = fetchlab(st);
jumplabel((int)sym->addr);
sym->usage |= uREAD; /* set "uREAD" bit */
/*
* // ??? if the label is defined (check sym->usage & uDEFINE), check
* // sym->compound (nesting level of the label) against nestlevel;
* // if sym->compound < nestlevel, call the destructor operator
*/
}
else
{
error(20, st); /* illegal symbol name */
} /* if */
needtoken(tTERM);
}
static void
dolabel(void)
{
char *st;
cell val;
symbol *sym;
tokeninfo(&val, &st); /* retrieve label name again */
if (find_constval(&tagname_tab, st, 0))
error(221, st); /* label name shadows tagname */
sym = fetchlab(st);
setlabel((int)sym->addr);
/* since one can jump around variable declarations or out of compound
* blocks, the stack must be manually adjusted
*/
setstk(-declared * sizeof(cell));
sym->usage |= uDEFINE; /* label is now defined */
}
/* fetchlab
*
* Finds a label from the (local) symbol table or adds one to it.
* Labels are local in scope.
*
* Note: The "_usage" bit is set to zero. The routines that call
* "fetchlab()" must set this bit accordingly.
*/
static symbol *
fetchlab(char *name)
{
symbol *sym;
sym = findloc(name); /* labels are local in scope */
if (sym)
{
if (sym->ident != iLABEL)
error(19, sym->name); /* not a label: ... */
}
else
{
sym = addsym(name, getlabel(), iLABEL, sLOCAL, 0, 0);
sym->x.declared = (int)declared;
sym->compound = nestlevel;
} /* if */
return sym;
}
/* doreturn
*
* Global references: rettype (altered)
*/
static void
doreturn(void)
{
int tag;
if (matchtoken(tTERM) == 0)
{
if ((rettype & uRETNONE) != 0)
error(208); /* mix "return;" and "return value;" */
doexpr(TRUE, FALSE, FALSE, TRUE, &tag, FALSE);
needtoken(tTERM);
rettype |= uRETVALUE; /* function returns a value */
/* check tagname with function tagname */
assert(curfunc != NULL);
if (!matchtag(curfunc->tag, tag, TRUE))
error(213); /* tagname mismatch */
}
else
{
/* this return statement contains no expression */
const1(0);
if ((rettype & uRETVALUE) != 0)
{
char symname[2 * sNAMEMAX + 16]; /* allow space for user
* defined operators */
assert(curfunc != NULL);
funcdisplayname(symname, curfunc->name);
error(209, symname); /* function should return a value */
} /* if */
rettype |= uRETNONE; /* function does not return anything */
} /* if */
destructsymbols(&loctab, 0); /*call destructor for *all* locals */
modstk((int)declared * sizeof(cell)); /* end of function, remove
*all* * local variables*/
ffret();
}
static void
dobreak(void)
{
int *ptr;
ptr = readwhile(); /* readwhile() gives an error if not in loop */
needtoken(tTERM);
if (!ptr)
return;
destructsymbols(&loctab, nestlevel);
modstk(((int)declared - ptr[wqBRK]) * sizeof(cell));
jumplabel(ptr[wqEXIT]);
}
static void
docont(void)
{
int *ptr;
ptr = readwhile(); /* readwhile() gives an error if not in loop */
needtoken(tTERM);
if (!ptr)
return;
destructsymbols(&loctab, nestlevel);
modstk(((int)declared - ptr[wqCONT]) * sizeof(cell));
jumplabel(ptr[wqLOOP]);
}
void
exporttag(int tag)
{
/* find the tag by value in the table, then set the top bit to mark it
* "public"
*/
if (tag != 0)
{
constvalue *ptr;
assert((tag & PUBLICTAG) == 0);
for (ptr = tagname_tab.next;
ptr && tag != (int)(ptr->value & TAGMASK); ptr = ptr->next)
/* nothing */ ;
if (ptr)
ptr->value |= PUBLICTAG;
} /* if */
}
static void
doexit(void)
{
int tag = 0;
if (matchtoken(tTERM) == 0)
{
doexpr(TRUE, FALSE, FALSE, TRUE, &tag, FALSE);
needtoken(tTERM);
}
else
{
const1(0);
} /* if */
const2(tag);
exporttag(tag);
destructsymbols(&loctab, 0); /* call destructor for *all* locals */
ffabort(xEXIT);
}
static void
dosleep(void)
{
int tag = 0;
if (matchtoken(tTERM) == 0)
{
doexpr(TRUE, FALSE, FALSE, TRUE, &tag, FALSE);
needtoken(tTERM);
}
else
{
const1(0);
} /* if */
const2(tag);
exporttag(tag);
ffabort(xSLEEP);
}
static void
addwhile(int *ptr)
{
int k;
ptr[wqBRK] = (int)declared; /* stack pointer (for "break") */
ptr[wqCONT] = (int)declared; /* for "continue", possibly adjusted later */
ptr[wqLOOP] = getlabel();
ptr[wqEXIT] = getlabel();
if (wqptr >= (wq + wqTABSZ - wqSIZE))
error(102, "loop table"); /* loop table overflow (too many active loops) */
k = 0;
while (k < wqSIZE)
{ /* copy "ptr" to while queue table */
*wqptr = *ptr;
wqptr += 1;
ptr += 1;
k += 1;
} /* while */
}
static void
delwhile(void)
{
if (wqptr > wq)
wqptr -= wqSIZE;
}
static int *
readwhile(void)
{
if (wqptr <= wq)
{
error(24); /* out of context */
return NULL;
}
else
{
return (wqptr - wqSIZE);
} /* if */
}
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