/* Parse C expressions for cpplib.
- Copyright (C) 1987, 92, 94, 95, 97, 98, 1999, 2000 Free Software Foundation.
+ Copyright (C) 1987, 1992, 1994, 1995, 1997, 1998, 1999, 2000, 2001
+ Free Software Foundation.
+ Contributed by Per Bothner, 1994.
This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA.
+Boston, MA 02111-1307, USA. */
- In other words, you are welcome to use, share and improve this program.
- You are forbidden to forbid anyone else to use, share and improve
- what you give them. Help stamp out software-hoarding!
-
-Written by Per Bothner 1994. */
-
-/* Parse a C expression from text in a string */
-
#include "config.h"
#include "system.h"
#include "cpplib.h"
-
-#ifdef MULTIBYTE_CHARS
-#include <locale.h>
-#endif
-
-#ifndef CHAR_TYPE_SIZE
-#define CHAR_TYPE_SIZE BITS_PER_UNIT
-#endif
-
-#ifndef INT_TYPE_SIZE
-#define INT_TYPE_SIZE BITS_PER_WORD
-#endif
-
-#ifndef LONG_TYPE_SIZE
-#define LONG_TYPE_SIZE BITS_PER_WORD
-#endif
-
-#ifndef WCHAR_TYPE_SIZE
-#define WCHAR_TYPE_SIZE INT_TYPE_SIZE
-#endif
-
-#ifndef MAX_CHAR_TYPE_SIZE
-#define MAX_CHAR_TYPE_SIZE CHAR_TYPE_SIZE
-#endif
-
-#ifndef MAX_INT_TYPE_SIZE
-#define MAX_INT_TYPE_SIZE INT_TYPE_SIZE
-#endif
-
-#ifndef MAX_LONG_TYPE_SIZE
-#define MAX_LONG_TYPE_SIZE LONG_TYPE_SIZE
-#endif
-
-#ifndef MAX_WCHAR_TYPE_SIZE
-#define MAX_WCHAR_TYPE_SIZE WCHAR_TYPE_SIZE
-#endif
-
-#define MAX_CHAR_TYPE_MASK (MAX_CHAR_TYPE_SIZE < HOST_BITS_PER_WIDEST_INT \
- ? (~(~(HOST_WIDEST_INT) 0 << MAX_CHAR_TYPE_SIZE)) \
- : ~ (HOST_WIDEST_INT) 0)
-
-#define MAX_WCHAR_TYPE_MASK (MAX_WCHAR_TYPE_SIZE < HOST_BITS_PER_WIDEST_INT \
- ? ~(~(HOST_WIDEST_INT) 0 << MAX_WCHAR_TYPE_SIZE) \
- : ~ (HOST_WIDEST_INT) 0)
+#include "cpphash.h"
/* Yield nonzero if adding two numbers with A's and B's signs can yield a
number with SUM's sign, where A, B, and SUM are all C integers. */
static HOST_WIDEST_INT right_shift PARAMS ((cpp_reader *, HOST_WIDEST_INT,
unsigned int,
unsigned HOST_WIDEST_INT));
-static struct operation parse_number PARAMS ((cpp_reader *, U_CHAR *,
- U_CHAR *));
-static struct operation parse_charconst PARAMS ((cpp_reader *, U_CHAR *,
- U_CHAR *));
-static struct operation parse_defined PARAMS ((cpp_reader *));
-static HOST_WIDEST_INT parse_escape PARAMS ((cpp_reader *, U_CHAR **,
- HOST_WIDEST_INT));
-static struct operation lex PARAMS ((cpp_reader *, int));
-
-
-#define ERROR 299
-#define OROR 300
-#define ANDAND 301
-#define EQUAL 302
-#define NOTEQUAL 303
-#define LEQ 304
-#define GEQ 305
-#define LSH 306
-#define RSH 307
-#define NAME 308
-#define INT 309
-#define CHAR 310
-
-#define LEFT_OPERAND_REQUIRED 1
-#define RIGHT_OPERAND_REQUIRED 2
-#define HAVE_VALUE 4
-/* SKIP_OPERAND is set for '&&' '||' '?' and ':' when the
- following operand should be short-circuited instead of evaluated. */
-#define SKIP_OPERAND 8
-
-struct operation
+static struct op parse_number PARAMS ((cpp_reader *, const cpp_token *));
+static struct op parse_defined PARAMS ((cpp_reader *));
+static struct op lex PARAMS ((cpp_reader *, int));
+static const unsigned char *op_as_text PARAMS ((cpp_reader *, enum cpp_ttype));
+
+struct op
{
- short op;
- U_CHAR rprio; /* Priority of op (relative to it right operand). */
+ enum cpp_ttype op;
+ U_CHAR prio; /* Priority of op. */
U_CHAR flags;
- U_CHAR unsignedp; /* true if value should be treated as unsigned */
- HOST_WIDEST_INT value; /* The value logically "right" of op. */
+ U_CHAR unsignedp; /* True if value should be treated as unsigned. */
+ HOST_WIDEST_INT value; /* The value logically "right" of op. */
};
-/* Parse and convert an integer for #if. Accepts decimal, hex, or octal
- with or without size suffixes. */
+/* There is no "error" token, but we can't get comments in #if, so we can
+ abuse that token type. */
+#define CPP_ERROR CPP_COMMENT
+
+/* With -O2, gcc appears to produce nice code, moving the error
+ message load and subsequent jump completely out of the main path. */
+#define CPP_ICE(msgid) \
+ do { cpp_ice (pfile, msgid); goto syntax_error; } while(0)
+#define SYNTAX_ERROR(msgid) \
+ do { cpp_error (pfile, msgid); goto syntax_error; } while(0)
+#define SYNTAX_ERROR2(msgid, arg) \
+ do { cpp_error (pfile, msgid, arg); goto syntax_error; } while(0)
-static struct operation
-parse_number (pfile, start, end)
+struct suffix
+{
+ const unsigned char s[4];
+ const unsigned char u;
+ const unsigned char l;
+};
+
+static const struct suffix vsuf_1[] = {
+ { "u", 1, 0 }, { "U", 1, 0 },
+ { "l", 0, 1 }, { "L", 0, 1 }
+};
+
+static const struct suffix vsuf_2[] = {
+ { "ul", 1, 1 }, { "UL", 1, 1 }, { "uL", 1, 1 }, { "Ul", 1, 1 },
+ { "lu", 1, 1 }, { "LU", 1, 1 }, { "Lu", 1, 1 }, { "lU", 1, 1 },
+ { "ll", 0, 2 }, { "LL", 0, 2 }
+};
+
+static const struct suffix vsuf_3[] = {
+ { "ull", 1, 2 }, { "ULL", 1, 2 }, { "uLL", 1, 2 }, { "Ull", 1, 2 },
+ { "llu", 1, 2 }, { "LLU", 1, 2 }, { "LLu", 1, 2 }, { "llU", 1, 2 }
+};
+#define Nsuff(tab) (sizeof tab / sizeof (struct suffix))
+
+/* Parse and convert an integer for #if. Accepts decimal, hex, or
+ octal with or without size suffixes. Returned op is CPP_ERROR on
+ error, otherwise it is a CPP_NUMBER. */
+
+static struct op
+parse_number (pfile, tok)
cpp_reader *pfile;
- U_CHAR *start;
- U_CHAR *end;
+ const cpp_token *tok;
{
- struct operation op;
- U_CHAR *p = start;
- int c;
+ struct op op;
+ const U_CHAR *start = tok->val.str.text;
+ const U_CHAR *end = start + tok->val.str.len;
+ const U_CHAR *p = start;
+ int c = 0, i, nsuff;
unsigned HOST_WIDEST_INT n = 0, nd, MAX_over_base;
int base = 10;
int overflow = 0;
int digit, largest_digit = 0;
- int spec_long = 0;
+ const struct suffix *sufftab;
op.unsignedp = 0;
MAX_over_base = (((unsigned HOST_WIDEST_INT) -1)
/ ((unsigned HOST_WIDEST_INT) base));
- while (p < end)
+ for(; p < end; p++)
{
- c = *p++;
-
- if (c >= '0' && c <= '9')
- digit = c - '0';
- else if (base == 16 && c >= 'a' && c <= 'f') /* FIXME: assumes ASCII */
- digit = c - 'a' + 10;
- else if (base == 16 && c >= 'A' && c <= 'F')
- digit = c - 'A' + 10;
- else if (c == '.')
- {
- /* It's a float since it contains a point. */
- cpp_error (pfile,
- "floating point numbers are not allowed in #if expressions");
- goto error;
- }
+ c = *p;
+
+ if (ISDIGIT (c)
+ || (base == 16 && ISXDIGIT (c)))
+ digit = hex_value (c);
else
- {
- /* `l' means long, and `u' means unsigned. */
- for (;;)
- {
- if (c == 'l' || c == 'L')
- spec_long++;
- else if (c == 'u' || c == 'U')
- op.unsignedp++;
- else
- {
- /* Decrement p here so that the error for an invalid number
- will be generated below in the case where this is the
- last character in the buffer. */
- p--;
- break;
- }
- if (p == end)
- break;
- c = *p++;
- }
- /* Don't look for any more digits after the suffixes. */
- break;
- }
-
+ break;
+
if (largest_digit < digit)
largest_digit = digit;
nd = n * base + digit;
n = nd;
}
- if (p != end)
+ if (p < end)
{
- cpp_error (pfile, "invalid number in #if expression");
- goto error;
- }
- else if (spec_long > (CPP_OPTIONS (pfile)->c89 ? 1 : 2))
- {
- cpp_error (pfile, "too many `l' suffixes in integer constant");
- goto error;
- }
- else if (op.unsignedp > 1)
- {
- cpp_error (pfile, "too many `u' suffixes in integer constant");
- goto error;
+ /* Check for a floating point constant. Note that float constants
+ with an exponent or suffix but no decimal point are technically
+ invalid (C99 6.4.4.2) but accepted elsewhere. */
+ if ((c == '.' || c == 'F' || c == 'f')
+ || (base == 10 && (c == 'E' || c == 'e')
+ && p+1 < end && (p[1] == '+' || p[1] == '-'))
+ || (base == 16 && (c == 'P' || c == 'p')
+ && p+1 < end && (p[1] == '+' || p[1] == '-')))
+ SYNTAX_ERROR ("floating point numbers are not valid in #if");
+
+ /* Determine the suffix. l means long, and u means unsigned.
+ See the suffix tables, above. */
+ switch (end - p)
+ {
+ case 1: sufftab = vsuf_1; nsuff = Nsuff(vsuf_1); break;
+ case 2: sufftab = vsuf_2; nsuff = Nsuff(vsuf_2); break;
+ case 3: sufftab = vsuf_3; nsuff = Nsuff(vsuf_3); break;
+ default: goto invalid_suffix;
+ }
+
+ for (i = 0; i < nsuff; i++)
+ if (memcmp (p, sufftab[i].s, end - p) == 0)
+ break;
+ if (i == nsuff)
+ goto invalid_suffix;
+ op.unsignedp = sufftab[i].u;
+
+ if (CPP_WTRADITIONAL (pfile)
+ && sufftab[i].u
+ && ! cpp_sys_macro_p (pfile))
+ cpp_warning (pfile, "traditional C rejects the `U' suffix");
+ if (sufftab[i].l == 2 && CPP_OPTION (pfile, pedantic)
+ && ! CPP_OPTION (pfile, c99))
+ cpp_pedwarn (pfile, "too many 'l' suffixes in integer constant");
}
if (base <= largest_digit)
else if ((HOST_WIDEST_INT) n < 0 && ! op.unsignedp)
{
if (base == 10)
- cpp_warning (pfile,
- "integer constant is so large that it is unsigned");
+ cpp_warning (pfile, "integer constant is so large that it is unsigned");
op.unsignedp = 1;
}
op.value = n;
- op.op = INT;
+ op.op = CPP_NUMBER;
return op;
- error:
- op.op = ERROR;
+ invalid_suffix:
+ cpp_error (pfile, "invalid suffix '%.*s' on integer constant",
+ (int) (end - p), p);
+ syntax_error:
+ op.op = CPP_ERROR;
return op;
}
-/* Parse and convert a character constant for #if. Understands backslash
- escapes (\n, \031) and multibyte characters (if so configured). */
-static struct operation
-parse_charconst (pfile, start, end)
+static struct op
+parse_defined (pfile)
cpp_reader *pfile;
- U_CHAR *start;
- U_CHAR *end;
{
- struct operation op;
- HOST_WIDEST_INT result = 0;
- int num_chars = 0;
- int num_bits;
- unsigned int width = MAX_CHAR_TYPE_SIZE, mask = MAX_CHAR_TYPE_MASK;
- int max_chars;
- U_CHAR *ptr = start;
+ int paren = 0;
+ cpp_hashnode *node = 0;
+ const cpp_token *token;
+ struct op op;
+ cpp_context *initial_context = pfile->context;
- int c = -1;
+ /* Don't expand macros. */
+ pfile->state.prevent_expansion++;
- if (*ptr == 'L')
+ token = cpp_get_token (pfile);
+ if (token->type == CPP_OPEN_PAREN)
{
- ++ptr;
- width = MAX_WCHAR_TYPE_SIZE, mask = MAX_WCHAR_TYPE_MASK;
+ paren = 1;
+ token = cpp_get_token (pfile);
}
- max_chars = MAX_LONG_TYPE_SIZE / width;
- ++ptr; /* skip initial quote */
-
- while (ptr < end)
+ if (token->type == CPP_NAME)
{
- c = *ptr++;
- if (c == '\'' || c == '\0')
- break;
- else if (c == '\\')
+ node = token->val.node;
+ if (paren && cpp_get_token (pfile)->type != CPP_CLOSE_PAREN)
{
- c = parse_escape (pfile, &ptr, mask);
- if (width < HOST_BITS_PER_INT
- && (unsigned int) c >= (unsigned int)(1 << width))
- cpp_pedwarn (pfile, "escape sequence out of range for character");
- }
-
- /* Merge character into result; ignore excess chars. */
- if (++num_chars <= max_chars)
- {
- if (width < HOST_BITS_PER_INT)
- result = (result << width) | (c & ((1 << width) - 1));
- else
- result = c;
+ cpp_error (pfile, "missing ')' after \"defined\"");
+ node = 0;
}
}
-
- if (num_chars == 0)
- {
- cpp_error (pfile, "empty character constant");
- goto error;
- }
- else if (c != '\'')
- {
- /* cpp_get_token has already emitted an error if !traditional. */
- if (! CPP_TRADITIONAL (pfile))
- cpp_error (pfile, "malformatted character constant");
- goto error;
- }
- else if (num_chars > max_chars)
+ else
{
- cpp_error (pfile, "character constant too long");
- goto error;
+ cpp_error (pfile, "operator \"defined\" requires an identifier");
+ if (token->flags & NAMED_OP)
+ {
+ cpp_token op;
+
+ op.flags = 0;
+ op.type = token->type;
+ cpp_error (pfile,
+ "(\"%s\" is an alternative token for \"%s\" in C++)",
+ cpp_token_as_text (pfile, token),
+ cpp_token_as_text (pfile, &op));
+ }
}
- else if (num_chars != 1 && ! CPP_TRADITIONAL (pfile))
- cpp_warning (pfile, "multi-character character constant");
- /* If char type is signed, sign-extend the constant. */
- num_bits = num_chars * width;
-
- if (cpp_defined (pfile, (const U_CHAR *)"__CHAR_UNSIGNED__",
- sizeof ("__CHAR_UNSIGNED__")-1)
- || ((result >> (num_bits - 1)) & 1) == 0)
- op.value = result & ((unsigned HOST_WIDEST_INT) ~0
- >> (HOST_BITS_PER_WIDEST_INT - num_bits));
+ if (!node)
+ op.op = CPP_ERROR;
else
- op.value = result | ~((unsigned HOST_WIDEST_INT) ~0
- >> (HOST_BITS_PER_WIDEST_INT - num_bits));
-
- /* This is always a signed type. */
- op.unsignedp = 0;
- op.op = CHAR;
- return op;
-
- error:
- op.op = ERROR;
- return op;
-}
-
-static struct operation
-parse_defined (pfile)
- cpp_reader *pfile;
-{
- int paren = 0, len;
- U_CHAR *tok;
- enum cpp_token token;
- struct operation op;
- long old_written = CPP_WRITTEN (pfile);
-
- op.unsignedp = 0;
- op.op = INT;
-
- pfile->no_macro_expand++;
- token = get_directive_token (pfile);
- if (token == CPP_LPAREN)
{
- paren++;
- CPP_SET_WRITTEN (pfile, old_written);
- token = get_directive_token (pfile);
- }
+ if (pfile->context != initial_context)
+ cpp_warning (pfile, "this use of \"defined\" may not be portable");
- if (token != CPP_NAME)
- goto oops;
-
- tok = pfile->token_buffer + old_written;
- len = CPP_PWRITTEN (pfile) - tok;
- op.value = cpp_defined (pfile, tok, len);
+ op.value = node->type == NT_MACRO;
+ op.unsignedp = 0;
+ op.op = CPP_NUMBER;
- if (paren)
- {
- if (get_directive_token (pfile) != CPP_RPAREN)
- goto oops;
+ /* A possible controlling macro of the form #if !defined ().
+ _cpp_parse_expr checks there was no other junk on the line. */
+ pfile->mi_ind_cmacro = node;
}
- CPP_SET_WRITTEN (pfile, old_written);
- pfile->no_macro_expand--;
- return op;
- oops:
- CPP_SET_WRITTEN (pfile, old_written);
- pfile->no_macro_expand--;
- cpp_error (pfile, "`defined' without an identifier");
-
- op.op = ERROR;
+ pfile->state.prevent_expansion--;
return op;
}
+/* Read a token. The returned type is CPP_NUMBER for a valid number
+ (an interpreted preprocessing number or character constant, or the
+ result of the "defined" or "#" operators), CPP_ERROR on error,
+ CPP_EOF, or the type of an operator token. */
-struct token {
- const char *operator;
- int token;
-};
-
-static const struct token tokentab2[] = {
- {"&&", ANDAND},
- {"||", OROR},
- {"<<", LSH},
- {">>", RSH},
- {"==", EQUAL},
- {"!=", NOTEQUAL},
- {"<=", LEQ},
- {">=", GEQ},
- {"++", ERROR},
- {"--", ERROR},
- {NULL, ERROR}
-};
-
-/* Read one token. */
-
-static struct operation
+static struct op
lex (pfile, skip_evaluation)
cpp_reader *pfile;
int skip_evaluation;
{
- const struct token *toktab;
- enum cpp_token token;
- struct operation op;
- U_CHAR *tok_start, *tok_end;
- long old_written;
-
- old_written = CPP_WRITTEN (pfile);
- token = get_directive_token (pfile);
-
- tok_start = pfile->token_buffer + old_written;
- tok_end = CPP_PWRITTEN (pfile);
- CPP_SET_WRITTEN (pfile, old_written);
- switch (token)
+ struct op op;
+ const cpp_token *token = cpp_get_token (pfile);
+
+ switch (token->type)
{
- case CPP_EOF: /* Should not happen ... */
- case CPP_VSPACE:
- op.op = 0;
- return op;
case CPP_NUMBER:
- return parse_number (pfile, tok_start, tok_end);
- case CPP_STRING:
- case CPP_WSTRING:
- cpp_error (pfile, "string constants are not allowed in #if expressions");
- op.op = ERROR;
- return op;
+ return parse_number (pfile, token);
case CPP_CHAR:
case CPP_WCHAR:
- return parse_charconst (pfile, tok_start, tok_end);
-
- case CPP_NAME:
- if (!strcmp (tok_start, "defined"))
- return parse_defined (pfile);
-
- op.op = INT;
- op.unsignedp = 0;
- op.value = 0;
+ {
+ unsigned int chars_seen;
- if (CPP_WARN_UNDEF (pfile) && !skip_evaluation)
- cpp_warning (pfile, "`%.*s' is not defined",
- (int) (tok_end - tok_start), tok_start);
- return op;
+ /* This is always a signed type. */
+ op.unsignedp = 0;
+ op.op = CPP_NUMBER;
+ op.value = cpp_interpret_charconst (pfile, token, 1, 0, &chars_seen);
+ return op;
+ }
- case CPP_ASSERTION:
- op.op = INT;
- op.unsignedp = 0;
- op.value = cpp_defined (pfile, tok_start, tok_end - tok_start);
- return op;
+ case CPP_STRING:
+ case CPP_WSTRING:
+ SYNTAX_ERROR ("string constants are not valid in #if");
case CPP_OTHER:
- /* See if it is a special token of length 2. */
- if (tok_start + 2 == tok_end)
- {
- for (toktab = tokentab2; toktab->operator != NULL; toktab++)
- if (tok_start[0] == toktab->operator[0]
- && tok_start[1] == toktab->operator[1])
- break;
- if (toktab->token == ERROR)
- cpp_error (pfile, "`%s' not allowed in operand of `#if'",
- tok_start);
- op.op = toktab->token;
+ if (ISGRAPH (token->val.c))
+ SYNTAX_ERROR2 ("invalid character '%c' in #if", token->val.c);
+ else
+ SYNTAX_ERROR2 ("invalid character '\\%03o' in #if", token->val.c);
+
+ case CPP_NAME:
+ if (token->val.node == pfile->spec_nodes.n_defined)
+ return parse_defined (pfile);
+ else if (CPP_OPTION (pfile, cplusplus)
+ && (token->val.node == pfile->spec_nodes.n_true
+ || token->val.node == pfile->spec_nodes.n_false))
+ {
+ op.op = CPP_NUMBER;
+ op.unsignedp = 0;
+ op.value = (token->val.node == pfile->spec_nodes.n_true);
+
+ /* Warn about use of true or false in #if when pedantic
+ and stdbool.h has not been included. */
+ if (CPP_PEDANTIC (pfile)
+ && ! cpp_defined (pfile, DSC("__bool_true_false_are_defined")))
+ cpp_pedwarn (pfile, "ISO C++ does not permit \"%s\" in #if",
+ NODE_NAME (token->val.node));
return op;
}
- /* fall through */
- default:
- op.op = *tok_start;
- return op;
- }
-}
-
-
-/* Parse a C escape sequence. STRING_PTR points to a variable
- containing a pointer to the string to parse. That pointer
- is updated past the characters we use. The value of the
- escape sequence is returned.
-
- A negative value means the sequence \ newline was seen,
- which is supposed to be equivalent to nothing at all.
-
- If \ is followed by a null character, we return a negative
- value and leave the string pointer pointing at the null character.
+ else
+ {
+ op.op = CPP_NUMBER;
+ op.unsignedp = 0;
+ op.value = 0;
- If \ is followed by 000, we return 0 and leave the string pointer
- after the zeros. A value of 0 does not mean end of string. */
+ if (CPP_OPTION (pfile, warn_undef) && !skip_evaluation)
+ cpp_warning (pfile, "\"%s\" is not defined",
+ NODE_NAME (token->val.node));
+ return op;
+ }
-static HOST_WIDEST_INT
-parse_escape (pfile, string_ptr, result_mask)
- cpp_reader *pfile;
- U_CHAR **string_ptr;
- HOST_WIDEST_INT result_mask;
-{
- register int c = *(*string_ptr)++;
- switch (c)
- {
- case 'a':
- return TARGET_BELL;
- case 'b':
- return TARGET_BS;
- case 'e':
- case 'E':
- if (CPP_OPTIONS (pfile)->pedantic)
- cpp_pedwarn (pfile, "non-ANSI-standard escape sequence, `\\%c'", c);
- return TARGET_ESC;
- case 'f':
- return TARGET_FF;
- case 'n':
- return TARGET_NEWLINE;
- case 'r':
- return TARGET_CR;
- case 't':
- return TARGET_TAB;
- case 'v':
- return TARGET_VT;
- case '\n':
- return -2;
- case 0:
- (*string_ptr)--;
- return 0;
-
- case '0':
- case '1':
- case '2':
- case '3':
- case '4':
- case '5':
- case '6':
- case '7':
+ case CPP_HASH:
{
- register HOST_WIDEST_INT i = c - '0';
- register int count = 0;
- while (++count < 3)
- {
- c = *(*string_ptr)++;
- if (c >= '0' && c <= '7')
- i = (i << 3) + c - '0';
- else
- {
- (*string_ptr)--;
- break;
- }
- }
- if (i != (i & result_mask))
- {
- i &= result_mask;
- cpp_pedwarn (pfile, "octal escape sequence out of range");
- }
- return i;
- }
- case 'x':
- {
- register unsigned HOST_WIDEST_INT i = 0, overflow = 0;
- register int digits_found = 0, digit;
- for (;;)
- {
- c = *(*string_ptr)++;
- if (c >= '0' && c <= '9')
- digit = c - '0';
- else if (c >= 'a' && c <= 'f')
- digit = c - 'a' + 10;
- else if (c >= 'A' && c <= 'F')
- digit = c - 'A' + 10;
- else
- {
- (*string_ptr)--;
- break;
- }
- overflow |= i ^ (i << 4 >> 4);
- i = (i << 4) + digit;
- digits_found = 1;
- }
- if (!digits_found)
- cpp_error (pfile, "\\x used with no following hex digits");
- if (overflow | (i != (i & result_mask)))
- {
- i &= result_mask;
- cpp_pedwarn (pfile, "hex escape sequence out of range");
- }
- return i;
+ int temp;
+
+ op.op = CPP_NUMBER;
+ if (_cpp_test_assertion (pfile, &temp))
+ op.op = CPP_ERROR;
+ op.unsignedp = 0;
+ op.value = temp;
+ return op;
}
+
default:
- return c;
+ if (((int) token->type > (int) CPP_EQ
+ && (int) token->type < (int) CPP_PLUS_EQ)
+ || token->type == CPP_EOF)
+ {
+ op.op = token->type;
+ return op;
+ }
+
+ SYNTAX_ERROR2 ("\"%s\" is not valid in #if expressions",
+ cpp_token_as_text (pfile, token));
}
+
+ syntax_error:
+ op.op = CPP_ERROR;
+ return op;
}
static void
return a >> b;
}
\f
-/* These priorities are all even, so we can handle associatively. */
-#define PAREN_INNER_PRIO 0
-#define COMMA_PRIO 4
-#define COND_PRIO (COMMA_PRIO+2)
-#define OROR_PRIO (COND_PRIO+2)
-#define ANDAND_PRIO (OROR_PRIO+2)
-#define OR_PRIO (ANDAND_PRIO+2)
-#define XOR_PRIO (OR_PRIO+2)
-#define AND_PRIO (XOR_PRIO+2)
-#define EQUAL_PRIO (AND_PRIO+2)
-#define LESS_PRIO (EQUAL_PRIO+2)
-#define SHIFT_PRIO (LESS_PRIO+2)
-#define PLUS_PRIO (SHIFT_PRIO+2)
-#define MUL_PRIO (PLUS_PRIO+2)
-#define UNARY_PRIO (MUL_PRIO+2)
-#define PAREN_OUTER_PRIO (UNARY_PRIO+2)
+/* Operator precedence and flags table.
+
+After an operator is returned from the lexer, if it has priority less
+than or equal to the operator on the top of the stack, we reduce the
+stack by one operator and repeat the test. Since equal priorities
+reduce, this is naturally left-associative.
+
+We handle right-associative operators by clearing the lower bit of all
+left-associative operators, and setting it for right-associative ones.
+After the reduction phase of a new operator, just before it is pushed
+onto the stack, its RIGHT_ASSOC bit is cleared. The effect is that
+during the reduction phase, the current right-associative operator has
+a priority one greater than any other operator of otherwise equal
+precedence that has been pushed on the top of the stack. This avoids
+a reduction pass, and effectively makes the logic right-associative.
+
+The remaining cases are '(' and ')'. We handle '(' by skipping the
+reduction phase completely. ')' is given lower priority than
+everything else, including '(', effectively forcing a reduction of the
+parenthesised expression. If there is no matching '(', the stack will
+be reduced all the way to the beginning, exiting the parser in the
+same way as the ultra-low priority end-of-expression dummy operator.
+The exit code checks to see if the operator that caused it is ')', and
+if so outputs an appropriate error message.
+
+The parser assumes all shifted operators require a right operand
+unless the flag NO_R_OPERAND is set, and similarly for NO_L_OPERAND.
+These semantics are automatically checked, any extra semantics need to
+be handled with operator-specific code. */
+
+#define FLAG_BITS 8
+#define FLAG_MASK ((1 << FLAG_BITS) - 1)
+#define PRIO_SHIFT (FLAG_BITS + 1)
+#define EXTRACT_PRIO(CNST) ((CNST) >> FLAG_BITS)
+#define EXTRACT_FLAGS(CNST) ((CNST) & FLAG_MASK)
+
+/* Flags. */
+#define HAVE_VALUE (1 << 0)
+#define NO_L_OPERAND (1 << 1)
+#define NO_R_OPERAND (1 << 2)
+#define SHORT_CIRCUIT (1 << 3)
+
+/* Priority and flag combinations. */
+#define RIGHT_ASSOC (1 << FLAG_BITS)
+#define FORCE_REDUCE_PRIO (0 << PRIO_SHIFT)
+#define CLOSE_PAREN_PRIO (1 << PRIO_SHIFT)
+#define OPEN_PAREN_PRIO ((2 << PRIO_SHIFT) | NO_L_OPERAND)
+#define COMMA_PRIO (3 << PRIO_SHIFT)
+#define COND_PRIO ((4 << PRIO_SHIFT) | RIGHT_ASSOC | SHORT_CIRCUIT)
+#define COLON_PRIO ((5 << PRIO_SHIFT) | SHORT_CIRCUIT)
+#define OROR_PRIO ((6 << PRIO_SHIFT) | SHORT_CIRCUIT)
+#define ANDAND_PRIO ((7 << PRIO_SHIFT) | SHORT_CIRCUIT)
+#define OR_PRIO (8 << PRIO_SHIFT)
+#define XOR_PRIO (9 << PRIO_SHIFT)
+#define AND_PRIO (10 << PRIO_SHIFT)
+#define MINMAX_PRIO (11 << PRIO_SHIFT)
+#define EQUAL_PRIO (12 << PRIO_SHIFT)
+#define LESS_PRIO (13 << PRIO_SHIFT)
+#define SHIFT_PRIO (14 << PRIO_SHIFT)
+#define PLUS_PRIO (15 << PRIO_SHIFT)
+#define MUL_PRIO (16 << PRIO_SHIFT)
+#define UNARY_PRIO ((17 << PRIO_SHIFT) | RIGHT_ASSOC | NO_L_OPERAND)
+
+/* Operator to priority map. Must be in the same order as the first
+ N entries of enum cpp_ttype. */
+static const short
+op_to_prio[] =
+{
+ /* EQ */ 0, /* dummy entry - can't happen */
+ /* NOT */ UNARY_PRIO,
+ /* GREATER */ LESS_PRIO,
+ /* LESS */ LESS_PRIO,
+ /* PLUS */ UNARY_PRIO, /* note these two can be unary */
+ /* MINUS */ UNARY_PRIO, /* or binary */
+ /* MULT */ MUL_PRIO,
+ /* DIV */ MUL_PRIO,
+ /* MOD */ MUL_PRIO,
+ /* AND */ AND_PRIO,
+ /* OR */ OR_PRIO,
+ /* XOR */ XOR_PRIO,
+ /* RSHIFT */ SHIFT_PRIO,
+ /* LSHIFT */ SHIFT_PRIO,
+ /* MIN */ MINMAX_PRIO, /* C++ specific */
+ /* MAX */ MINMAX_PRIO, /* extensions */
+
+ /* COMPL */ UNARY_PRIO,
+ /* AND_AND */ ANDAND_PRIO,
+ /* OR_OR */ OROR_PRIO,
+ /* QUERY */ COND_PRIO,
+ /* COLON */ COLON_PRIO,
+ /* COMMA */ COMMA_PRIO,
+ /* OPEN_PAREN */ OPEN_PAREN_PRIO,
+ /* CLOSE_PAREN */ CLOSE_PAREN_PRIO,
+ /* EQ_EQ */ EQUAL_PRIO,
+ /* NOT_EQ */ EQUAL_PRIO,
+ /* GREATER_EQ */ LESS_PRIO,
+ /* LESS_EQ */ LESS_PRIO
+};
#define COMPARE(OP) \
- top->unsignedp = 0;\
- top->value = (unsigned1 || unsigned2) \
- ? (unsigned HOST_WIDEST_INT) v1 OP (unsigned HOST_WIDEST_INT) v2 : (v1 OP v2)
+ top->unsignedp = 0; \
+ top->value = (unsigned1 | unsigned2) \
+ ? (unsigned HOST_WIDEST_INT) v1 OP (unsigned HOST_WIDEST_INT) v2 \
+ : (v1 OP v2)
+#define EQUALITY(OP) \
+ top->value = v1 OP v2; \
+ top->unsignedp = 0;
+#define BITWISE(OP) \
+ top->value = v1 OP v2; \
+ top->unsignedp = unsigned1 | unsigned2;
+#define MINMAX(OP) \
+ top->value = (v1 OP v2) ? v1 : v2; \
+ top->unsignedp = unsigned1 | unsigned2;
+#define UNARY(OP) \
+ top->value = OP v2; \
+ top->unsignedp = unsigned2; \
+ top->flags |= HAVE_VALUE;
+#define SHIFT(PSH, MSH) \
+ if (skip_evaluation) \
+ break; \
+ top->unsignedp = unsigned1; \
+ if (v2 < 0 && ! unsigned2) \
+ top->value = MSH (pfile, v1, unsigned1, -v2); \
+ else \
+ top->value = PSH (pfile, v1, unsigned1, v2);
/* Parse and evaluate a C expression, reading from PFILE.
- Returns the value of the expression. */
+ Returns the truth value of the expression. */
-HOST_WIDEST_INT
+int
_cpp_parse_expr (pfile)
cpp_reader *pfile;
{
- /* The implementation is an operator precedence parser,
- i.e. a bottom-up parser, using a stack for not-yet-reduced tokens.
+ /* The implementation is an operator precedence parser, i.e. a
+ bottom-up parser, using a stack for not-yet-reduced tokens.
The stack base is 'stack', and the current stack pointer is 'top'.
There is a stack element for each operator (only),
In that case the 'flags' field has the HAVE_VALUE flag set. */
#define INIT_STACK_SIZE 20
- struct operation init_stack[INIT_STACK_SIZE];
- struct operation *stack = init_stack;
- struct operation *limit = stack + INIT_STACK_SIZE;
- register struct operation *top = stack;
- unsigned int lprio, rprio = 0;
+ struct op init_stack[INIT_STACK_SIZE];
+ struct op *stack = init_stack;
+ struct op *limit = stack + INIT_STACK_SIZE;
+ struct op *top = stack + 1;
int skip_evaluation = 0;
+ int result;
+ unsigned int lex_count, saw_leading_not;
+
+ /* Set up detection of #if ! defined(). */
+ pfile->mi_ind_cmacro = 0;
+ saw_leading_not = 0;
+ lex_count = 0;
+
+ /* We've finished when we try to reduce this. */
+ top->op = CPP_EOF;
+ /* Nifty way to catch missing '('. */
+ top->prio = EXTRACT_PRIO(CLOSE_PAREN_PRIO);
+ /* Avoid missing right operand checks. */
+ top->flags = NO_R_OPERAND;
- top->rprio = 0;
- top->flags = 0;
for (;;)
{
- struct operation op;
- U_CHAR flags = 0;
+ unsigned int prio;
+ unsigned int flags;
+ struct op op;
/* Read a token */
- op = lex (pfile, skip_evaluation);
-
- /* See if the token is an operand, in which case go to set_value.
- If the token is an operator, figure out its left and right
- priorities, and then goto maybe_reduce. */
+ op = lex (pfile, skip_evaluation);
+ lex_count++;
+ /* If the token is an operand, push its value and get next
+ token. If it is an operator, get its priority and flags, and
+ try to reduce the expression on the stack. */
switch (op.op)
{
- case NAME:
- cpp_ice (pfile, "lex returns a NAME");
+ case CPP_ERROR:
goto syntax_error;
- case INT: case CHAR:
- goto set_value;
- case 0:
- lprio = 0; goto maybe_reduce;
- case '+': case '-':
+ push_immediate:
+ case CPP_NUMBER:
+ /* Push a value onto the stack. */
if (top->flags & HAVE_VALUE)
- {
- lprio = PLUS_PRIO;
- goto binop;
- }
- /* else fall through */
- case '!': case '~':
- flags = RIGHT_OPERAND_REQUIRED;
- rprio = UNARY_PRIO; lprio = rprio + 1; goto maybe_reduce;
- case '*': case '/': case '%':
- lprio = MUL_PRIO; goto binop;
- case '<': case '>': case LEQ: case GEQ:
- lprio = LESS_PRIO; goto binop;
- case EQUAL: case NOTEQUAL:
- lprio = EQUAL_PRIO; goto binop;
- case LSH: case RSH:
- lprio = SHIFT_PRIO; goto binop;
- case '&': lprio = AND_PRIO; goto binop;
- case '^': lprio = XOR_PRIO; goto binop;
- case '|': lprio = OR_PRIO; goto binop;
- case ANDAND: lprio = ANDAND_PRIO; goto binop;
- case OROR: lprio = OROR_PRIO; goto binop;
- case ',':
- lprio = COMMA_PRIO; goto binop;
- case '(':
- lprio = PAREN_OUTER_PRIO; rprio = PAREN_INNER_PRIO;
- goto maybe_reduce;
- case ')':
- lprio = PAREN_INNER_PRIO; rprio = PAREN_OUTER_PRIO;
- goto maybe_reduce;
- case ':':
- lprio = COND_PRIO; rprio = COND_PRIO;
- goto maybe_reduce;
- case '?':
- lprio = COND_PRIO + 1; rprio = COND_PRIO;
- goto maybe_reduce;
- case ERROR:
- goto syntax_error;
- default:
- cpp_error (pfile, "invalid character in #if");
- goto syntax_error;
- }
+ SYNTAX_ERROR ("missing binary operator");
+ top->value = op.value;
+ top->unsignedp = op.unsignedp;
+ top->flags |= HAVE_VALUE;
+ continue;
- set_value:
- /* Push a value onto the stack. */
- if (top->flags & HAVE_VALUE)
- {
- cpp_error (pfile, "syntax error in #if");
- goto syntax_error;
+ case CPP_EOF: prio = FORCE_REDUCE_PRIO; break;
+
+ case CPP_NOT:
+ saw_leading_not = lex_count == 1;
+ prio = op_to_prio[op.op];
+ break;
+ case CPP_PLUS:
+ case CPP_MINUS: prio = PLUS_PRIO; if (top->flags & HAVE_VALUE) break;
+ /* else unary; fall through */
+ default: prio = op_to_prio[op.op]; break;
}
- top->value = op.value;
- top->unsignedp = op.unsignedp;
- top->flags |= HAVE_VALUE;
- continue;
-
- binop:
- flags = LEFT_OPERAND_REQUIRED|RIGHT_OPERAND_REQUIRED;
- rprio = lprio + 1;
-
- maybe_reduce:
- /* Push an operator, and check if we can reduce now. */
- while (top->rprio > lprio)
+
+ /* Separate the operator's code into priority and flags. */
+ flags = EXTRACT_FLAGS(prio);
+ prio = EXTRACT_PRIO(prio);
+ if (prio == EXTRACT_PRIO(OPEN_PAREN_PRIO))
+ goto skip_reduction;
+
+ /* Check for reductions. Then push the operator. */
+ while (prio <= top->prio)
{
- HOST_WIDEST_INT v1 = top[-1].value, v2 = top[0].value;
- unsigned int unsigned1 = top[-1].unsignedp;
- unsigned int unsigned2 = top[0].unsignedp;
- top--;
- if ((top[1].flags & LEFT_OPERAND_REQUIRED)
- && ! (top[0].flags & HAVE_VALUE))
- {
- cpp_error (pfile, "syntax error - missing left operand");
- goto syntax_error;
- }
- if ((top[1].flags & RIGHT_OPERAND_REQUIRED)
- && ! (top[1].flags & HAVE_VALUE))
+ HOST_WIDEST_INT v1, v2;
+ unsigned int unsigned1, unsigned2;
+
+ /* Most operators that can appear on the stack require a
+ right operand. Check this before trying to reduce. */
+ if ((top->flags & (HAVE_VALUE | NO_R_OPERAND)) == 0)
{
- cpp_error (pfile, "syntax error - missing right operand");
- goto syntax_error;
+ if (top->op == CPP_OPEN_PAREN)
+ SYNTAX_ERROR ("void expression between '(' and ')'");
+ else
+ SYNTAX_ERROR2 ("operator '%s' has no right operand",
+ op_as_text (pfile, top->op));
}
- /* top[0].value = (top[1].op)(v1, v2);*/
+
+ unsigned2 = top->unsignedp, v2 = top->value;
+ top--;
+ unsigned1 = top->unsignedp, v1 = top->value;
+
+ /* Now set top->value = (top[1].op)(v1, v2); */
switch (top[1].op)
{
- case '+':
+ default:
+ cpp_ice (pfile, "impossible operator '%s'",
+ op_as_text (pfile, top[1].op));
+ goto syntax_error;
+
+ case CPP_NOT: UNARY(!); break;
+ case CPP_COMPL: UNARY(~); break;
+ case CPP_LESS: COMPARE(<); break;
+ case CPP_GREATER: COMPARE(>); break;
+ case CPP_LESS_EQ: COMPARE(<=); break;
+ case CPP_GREATER_EQ: COMPARE(>=); break;
+ case CPP_EQ_EQ: EQUALITY(==); break;
+ case CPP_NOT_EQ: EQUALITY(!=); break;
+ case CPP_AND: BITWISE(&); break;
+ case CPP_XOR: BITWISE(^); break;
+ case CPP_OR: BITWISE(|); break;
+ case CPP_LSHIFT: SHIFT(left_shift, right_shift); break;
+ case CPP_RSHIFT: SHIFT(right_shift, left_shift); break;
+ case CPP_MIN: MINMAX(<); break;
+ case CPP_MAX: MINMAX(>); break;
+
+ case CPP_PLUS:
if (!(top->flags & HAVE_VALUE))
- { /* Unary '+' */
+ {
+ /* Can't use UNARY(+) because K+R C did not have unary
+ plus. Can't use UNARY() because some compilers object
+ to the empty argument. */
top->value = v2;
top->unsignedp = unsigned2;
top->flags |= HAVE_VALUE;
+
+ if (CPP_WTRADITIONAL (pfile))
+ cpp_warning (pfile,
+ "traditional C rejects the unary plus operator");
}
else
{
top->value = v1 + v2;
- top->unsignedp = unsigned1 || unsigned2;
+ top->unsignedp = unsigned1 | unsigned2;
if (! top->unsignedp && ! skip_evaluation
&& ! possible_sum_sign (v1, v2, top->value))
integer_overflow (pfile);
}
break;
- case '-':
+ case CPP_MINUS:
if (!(top->flags & HAVE_VALUE))
- { /* Unary '-' */
- top->value = - v2;
+ {
+ UNARY(-);
if (!skip_evaluation && (top->value & v2) < 0 && !unsigned2)
integer_overflow (pfile);
- top->unsignedp = unsigned2;
- top->flags |= HAVE_VALUE;
}
else
{ /* Binary '-' */
top->value = v1 - v2;
- top->unsignedp = unsigned1 || unsigned2;
+ top->unsignedp = unsigned1 | unsigned2;
if (! top->unsignedp && ! skip_evaluation
&& ! possible_sum_sign (top->value, v2, v1))
integer_overflow (pfile);
}
break;
- case '*':
- top->unsignedp = unsigned1 || unsigned2;
+ case CPP_MULT:
+ top->unsignedp = unsigned1 | unsigned2;
if (top->unsignedp)
top->value = (unsigned HOST_WIDEST_INT) v1 * v2;
else if (!skip_evaluation)
{
top->value = v1 * v2;
- if (v1
- && (top->value / v1 != v2
- || (top->value & v1 & v2) < 0))
- integer_overflow (pfile);
- }
- break;
- case '/':
- if (skip_evaluation)
- break;
- if (v2 == 0)
- {
- cpp_error (pfile, "division by zero in #if");
- v2 = 1;
- }
- top->unsignedp = unsigned1 || unsigned2;
- if (top->unsignedp)
- top->value = (unsigned HOST_WIDEST_INT) v1 / v2;
- else
- {
- top->value = v1 / v2;
- if ((top->value & v1 & v2) < 0)
+ if (v1 && (top->value / v1 != v2
+ || (top->value & v1 & v2) < 0))
integer_overflow (pfile);
}
break;
- case '%':
+ case CPP_DIV:
+ case CPP_MOD:
if (skip_evaluation)
break;
if (v2 == 0)
+ SYNTAX_ERROR ("division by zero in #if");
+ top->unsignedp = unsigned1 | unsigned2;
+ if (top[1].op == CPP_DIV)
{
- cpp_error (pfile, "division by zero in #if");
- v2 = 1;
+ if (top->unsignedp)
+ top->value = (unsigned HOST_WIDEST_INT) v1 / v2;
+ else
+ {
+ top->value = v1 / v2;
+ if ((top->value & v1 & v2) < 0)
+ integer_overflow (pfile);
+ }
}
- top->unsignedp = unsigned1 || unsigned2;
- if (top->unsignedp)
- top->value = (unsigned HOST_WIDEST_INT) v1 % v2;
else
- top->value = v1 % v2;
- break;
- case '!':
- if (top->flags & HAVE_VALUE)
{
- cpp_error (pfile, "syntax error");
- goto syntax_error;
+ if (top->unsignedp)
+ top->value = (unsigned HOST_WIDEST_INT) v1 % v2;
+ else
+ top->value = v1 % v2;
}
- top->value = ! v2;
- top->unsignedp = 0;
- top->flags |= HAVE_VALUE;
break;
- case '~':
- if (top->flags & HAVE_VALUE)
- {
- cpp_error (pfile, "syntax error");
- goto syntax_error;
- }
- top->value = ~ v2;
- top->unsignedp = unsigned2;
- top->flags |= HAVE_VALUE;
- break;
- case '<': COMPARE(<); break;
- case '>': COMPARE(>); break;
- case LEQ: COMPARE(<=); break;
- case GEQ: COMPARE(>=); break;
- case EQUAL:
- top->value = (v1 == v2);
+
+ case CPP_OR_OR:
+ top->value = v1 || v2;
top->unsignedp = 0;
+ if (v1) skip_evaluation--;
break;
- case NOTEQUAL:
- top->value = (v1 != v2);
+ case CPP_AND_AND:
+ top->value = v1 && v2;
top->unsignedp = 0;
- break;
- case LSH:
- if (skip_evaluation)
- break;
- top->unsignedp = unsigned1;
- if (v2 < 0 && ! unsigned2)
- top->value = right_shift (pfile, v1, unsigned1, -v2);
- else
- top->value = left_shift (pfile, v1, unsigned1, v2);
- break;
- case RSH:
- if (skip_evaluation)
- break;
- top->unsignedp = unsigned1;
- if (v2 < 0 && ! unsigned2)
- top->value = left_shift (pfile, v1, unsigned1, -v2);
- else
- top->value = right_shift (pfile, v1, unsigned1, v2);
- break;
-#define LOGICAL(OP) \
- top->value = v1 OP v2;\
- top->unsignedp = unsigned1 || unsigned2;
- case '&': LOGICAL(&); break;
- case '^': LOGICAL(^); break;
- case '|': LOGICAL(|); break;
- case ANDAND:
- top->value = v1 && v2; top->unsignedp = 0;
if (!v1) skip_evaluation--;
break;
- case OROR:
- top->value = v1 || v2; top->unsignedp = 0;
- if (v1) skip_evaluation--;
- break;
- case ',':
+ case CPP_COMMA:
if (CPP_PEDANTIC (pfile))
- cpp_pedwarn (pfile, "comma operator in operand of `#if'");
+ cpp_pedwarn (pfile, "comma operator in operand of #if");
top->value = v2;
top->unsignedp = unsigned2;
break;
- case '(': case '?':
- cpp_error (pfile, "syntax error in #if");
- goto syntax_error;
- case ':':
- if (top[0].op != '?')
- {
- cpp_error (pfile,
- "syntax error ':' without preceding '?'");
- goto syntax_error;
- }
- else if (! (top[1].flags & HAVE_VALUE)
- || !(top[-1].flags & HAVE_VALUE)
- || !(top[0].flags & HAVE_VALUE))
- {
- cpp_error (pfile, "bad syntax for ?: operator");
- goto syntax_error;
- }
- else
- {
- top--;
- if (top->value) skip_evaluation--;
- top->value = top->value ? v1 : v2;
- top->unsignedp = unsigned1 || unsigned2;
- }
+ case CPP_QUERY:
+ SYNTAX_ERROR ("syntax error '?' without following ':'");
+ case CPP_COLON:
+ if (top[0].op != CPP_QUERY)
+ SYNTAX_ERROR ("syntax error ':' without preceding '?'");
+ top--;
+ if (top->value) skip_evaluation--;
+ top->value = top->value ? v1 : v2;
+ top->unsignedp = unsigned1 | unsigned2;
break;
- case ')':
- if ((top[1].flags & HAVE_VALUE)
- || ! (top[0].flags & HAVE_VALUE)
- || top[0].op != '('
- || (top[-1].flags & HAVE_VALUE))
- {
- cpp_error (pfile, "mismatched parentheses in #if");
- goto syntax_error;
- }
- else
- {
- top--;
- top->value = v1;
- top->unsignedp = unsigned1;
- top->flags |= HAVE_VALUE;
- }
- break;
- default:
- if (ISGRAPH (top[1].op))
- cpp_error (pfile, "unimplemented operator '%c'\n", top[1].op);
- else
- cpp_error (pfile, "unimplemented operator '\\%03o'\n",
- top[1].op);
+ case CPP_OPEN_PAREN:
+ if (op.op != CPP_CLOSE_PAREN)
+ SYNTAX_ERROR ("missing ')' in expression");
+ op.value = v2;
+ op.unsignedp = unsigned2;
+ goto push_immediate;
+ case CPP_EOF:
+ /* Reducing this dummy operator indicates we've finished. */
+ if (op.op == CPP_CLOSE_PAREN)
+ SYNTAX_ERROR ("missing '(' in expression");
+ goto done;
}
}
- if (op.op == 0)
+
+ /* Handle short-circuit evaluations. */
+ if (flags & SHORT_CIRCUIT)
+ switch (op.op)
+ {
+ case CPP_OR_OR: if (top->value) skip_evaluation++; break;
+ case CPP_AND_AND:
+ case CPP_QUERY: if (!top->value) skip_evaluation++; break;
+ case CPP_COLON:
+ if (top[-1].value) /* Was '?' condition true? */
+ skip_evaluation++;
+ else
+ skip_evaluation--;
+ default:
+ break;
+ }
+
+ skip_reduction:
+ /* Check we have a left operand iff we need one. */
+ if (flags & NO_L_OPERAND)
{
- if (top != stack)
- cpp_ice (pfile, "unbalanced stack in #if expression");
- if (stack != init_stack)
- free (stack);
- return top->value;
+ if (top->flags & HAVE_VALUE)
+ SYNTAX_ERROR2 ("missing binary operator before '%s'",
+ op_as_text (pfile, op.op));
}
- top++;
-
+ else
+ {
+ if (!(top->flags & HAVE_VALUE))
+ SYNTAX_ERROR2 ("operator '%s' has no left operand",
+ op_as_text (pfile, op.op));
+ }
+
/* Check for and handle stack overflow. */
+ top++;
if (top == limit)
{
- struct operation *new_stack;
+ struct op *new_stack;
int old_size = (char *) limit - (char *) stack;
int new_size = 2 * old_size;
if (stack != init_stack)
- new_stack = (struct operation *) xrealloc (stack, new_size);
+ new_stack = (struct op *) xrealloc (stack, new_size);
else
{
- new_stack = (struct operation *) xmalloc (new_size);
+ new_stack = (struct op *) xmalloc (new_size);
memcpy (new_stack, stack, old_size);
}
stack = new_stack;
- top = (struct operation *) ((char *) new_stack + old_size);
- limit = (struct operation *) ((char *) new_stack + new_size);
+ top = (struct op *) ((char *) new_stack + old_size);
+ limit = (struct op *) ((char *) new_stack + new_size);
}
top->flags = flags;
- top->rprio = rprio;
+ top->prio = prio & ~EXTRACT_PRIO(RIGHT_ASSOC);
top->op = op.op;
- if ((op.op == OROR && top[-1].value)
- || (op.op == ANDAND && !top[-1].value)
- || (op.op == '?' && !top[-1].value))
- {
- skip_evaluation++;
- }
- else if (op.op == ':')
- {
- if (top[-2].value) /* Was condition true? */
- skip_evaluation++;
- else
- skip_evaluation--;
- }
}
- syntax_error:
+
+ done:
+ /* The controlling macro expression is only valid if we called lex 3
+ times: <!> <defined expression> and <EOF>. push_conditional ()
+ checks that we are at top-of-file. */
+ if (pfile->mi_ind_cmacro && !(saw_leading_not && lex_count == 3))
+ pfile->mi_ind_cmacro = 0;
+
+ result = (top[1].value != 0);
+
+ if (top != stack)
+ CPP_ICE ("unbalanced stack in #if");
+ else if (!(top[1].flags & HAVE_VALUE))
+ {
+ SYNTAX_ERROR ("#if with no expression");
+ syntax_error:
+ result = 0; /* Return 0 on syntax error. */
+ }
+
+ /* Free dynamic stack if we allocated one. */
if (stack != init_stack)
free (stack);
- return 0;
+ return result;
+}
+
+static const unsigned char *
+op_as_text (pfile, op)
+ cpp_reader *pfile;
+ enum cpp_ttype op;
+{
+ cpp_token token;
+
+ token.type = op;
+ token.flags = 0;
+ return cpp_token_as_text (pfile, &token);
}
OSDN Git Service
