make ptrlist walking against robust against empty blocks

[smatch.git] / lib.c

/*
 * 'sparse' library helper routines.
 *
 * Copyright (C) 2003 Transmeta Corp.
 *               2003-2004 Linus Torvalds
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include <ctype.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <assert.h>

#include <sys/types.h>

#include "lib.h"
#include "allocate.h"
#include "token.h"
#include "parse.h"
#include "symbol.h"
#include "expression.h"
#include "scope.h"
#include "linearize.h"
#include "target.h"
#include "version.h"

int verbose, optimize, optimize_size, preprocessing;
int die_if_error = 0;

#ifndef __GNUC__
# define __GNUC__ 2
# define __GNUC_MINOR__ 95
# define __GNUC_PATCHLEVEL__ 0
#endif

int gcc_major = __GNUC__;
int gcc_minor = __GNUC_MINOR__;
int gcc_patchlevel = __GNUC_PATCHLEVEL__;

static const char *gcc_base_dir = GCC_BASE;
static const char *multiarch_dir = MULTIARCH_TRIPLET;

struct token *skip_to(struct token *token, int op)
{
        while (!match_op(token, op) && !eof_token(token))
                token = token->next;
        return token;
}

struct token *expect(struct token *token, int op, const char *where)
{
        if (!match_op(token, op)) {
                static struct token bad_token;
                if (token != &bad_token) {
                        bad_token.next = token;
                        sparse_error(token->pos, "Expected %s %s", show_special(op), where);
                        sparse_error(token->pos, "got %s", show_token(token));
                }
                if (op == ';')
                        return skip_to(token, op);
                return &bad_token;
        }
        return token->next;
}

unsigned int hexval(unsigned int c)
{
        int retval = 256;
        switch (c) {
        case '0'...'9':
                retval = c - '0';
                break;
        case 'a'...'f':
                retval = c - 'a' + 10;
                break;
        case 'A'...'F':
                retval = c - 'A' + 10;
                break;
        }
        return retval;
}

static void do_warn(const char *type, struct position pos, const char * fmt, va_list args)
{
        static char buffer[512];
        const char *name;

        vsprintf(buffer, fmt, args);    
        name = stream_name(pos.stream);
                
        fprintf(stderr, "%s:%d:%d: %s%s\n",
                name, pos.line, pos.pos, type, buffer);
}

static int max_warnings = 100;
static int show_info = 1;

void info(struct position pos, const char * fmt, ...)
{
        va_list args;

        if (!show_info)
                return;
        va_start(args, fmt);
        do_warn("", pos, fmt, args);
        va_end(args);
}

static void do_error(struct position pos, const char * fmt, va_list args)
{
        static int errors = 0;
        die_if_error = 1;
        show_info = 1;
        /* Shut up warnings after an error */
        max_warnings = 0;
        if (errors > 100) {
                static int once = 0;
                show_info = 0;
                if (once)
                        return;
                fmt = "too many errors";
                once = 1;
        }

        do_warn("error: ", pos, fmt, args);
        errors++;
}       

void warning(struct position pos, const char * fmt, ...)
{
        va_list args;

        if (Wsparse_error) {
                va_start(args, fmt);
                do_error(pos, fmt, args);
                va_end(args);
                return;
        }

        if (!max_warnings) {
                show_info = 0;
                return;
        }

        if (!--max_warnings) {
                show_info = 0;
                fmt = "too many warnings";
        }

        va_start(args, fmt);
        do_warn("warning: ", pos, fmt, args);
        va_end(args);
}

void sparse_error(struct position pos, const char * fmt, ...)
{
        va_list args;
        va_start(args, fmt);
        do_error(pos, fmt, args);
        va_end(args);
}

void expression_error(struct expression *expr, const char *fmt, ...)
{
        va_list args;
        va_start(args, fmt);
        do_error(expr->pos, fmt, args);
        va_end(args);
        expr->ctype = &bad_ctype;
}

void error_die(struct position pos, const char * fmt, ...)
{
        va_list args;
        va_start(args, fmt);
        do_warn("error: ", pos, fmt, args);
        va_end(args);
        exit(1);
}

void die(const char *fmt, ...)
{
        va_list args;
        static char buffer[512];

        va_start(args, fmt);
        vsnprintf(buffer, sizeof(buffer), fmt, args);
        va_end(args);

        fprintf(stderr, "%s\n", buffer);
        exit(1);
}

static struct token *pre_buffer_begin = NULL;
static struct token *pre_buffer_end = NULL;

int Waddress_space = 1;
int Wbitwise = 0;
int Wcast_to_as = 0;
int Wcast_truncate = 1;
int Wcontext = 1;
int Wdecl = 1;
int Wdeclarationafterstatement = -1;
int Wdefault_bitfield_sign = 0;
int Wdesignated_init = 1;
int Wdo_while = 0;
int Winit_cstring = 0;
int Wenum_mismatch = 1;
int Wsparse_error = 0;
int Wnon_pointer_null = 1;
int Wold_initializer = 1;
int Wone_bit_signed_bitfield = 1;
int Wparen_string = 0;
int Wptr_subtraction_blows = 0;
int Wreturn_void = 0;
int Wshadow = 0;
int Wsizeof_bool = 0;
int Wtransparent_union = 0;
int Wtypesign = 0;
int Wundef = 0;
int Wuninitialized = 1;
int Wunknown_attribute = 1;
int Wvla = 1;

int dbg_entry = 0;
int dbg_dead = 0;

int preprocess_only;

static enum { STANDARD_C89,
              STANDARD_C94,
              STANDARD_C99,
              STANDARD_GNU89,
              STANDARD_GNU99, } standard = STANDARD_GNU89;

#ifdef __x86_64__
#define ARCH_M64_DEFAULT 1
#else
#define ARCH_M64_DEFAULT 0
#endif

int arch_m64 = ARCH_M64_DEFAULT;
int arch_msize_long = 0;

#define CMDLINE_INCLUDE 20
static int cmdline_include_nr = 0;
static char *cmdline_include[CMDLINE_INCLUDE];


void add_pre_buffer(const char *fmt, ...)
{
        va_list args;
        unsigned int size;
        struct token *begin, *end;
        char buffer[4096];

        va_start(args, fmt);
        size = vsnprintf(buffer, sizeof(buffer), fmt, args);
        va_end(args);
        begin = tokenize_buffer(buffer, size, &end);
        if (!pre_buffer_begin)
                pre_buffer_begin = begin;
        if (pre_buffer_end)
                pre_buffer_end->next = begin;
        pre_buffer_end = end;
}

static char **handle_switch_D(char *arg, char **next)
{
        const char *name = arg + 1;
        const char *value = "1";

        if (!*name || isspace((unsigned char)*name))
                die("argument to `-D' is missing");

        for (;;) {
                char c;
                c = *++arg;
                if (!c)
                        break;
                if (isspace((unsigned char)c) || c == '=') {
                        *arg = '\0';
                        value = arg + 1;
                        break;
                }
        }
        add_pre_buffer("#define %s %s\n", name, value);
        return next;
}

static char **handle_switch_E(char *arg, char **next)
{
        if (arg[1] == '\0')
                preprocess_only = 1;
        return next;
}

static char **handle_switch_I(char *arg, char **next)
{
        char *path = arg+1;

        switch (arg[1]) {
        case '-':
                add_pre_buffer("#split_include\n");
                break;

        case '\0':      /* Plain "-I" */
                path = *++next;
                if (!path)
                        die("missing argument for -I option");
                /* Fall through */
        default:
                add_pre_buffer("#add_include \"%s/\"\n", path);
        }
        return next;
}

static void add_cmdline_include(char *filename)
{
        if (cmdline_include_nr >= CMDLINE_INCLUDE)
                die("too many include files for %s\n", filename);
        cmdline_include[cmdline_include_nr++] = filename;
}

static char **handle_switch_i(char *arg, char **next)
{
        if (*next && !strcmp(arg, "include"))
                add_cmdline_include(*++next);
        else if (*next && !strcmp(arg, "imacros"))
                add_cmdline_include(*++next);
        else if (*next && !strcmp(arg, "isystem")) {
                char *path = *++next;
                if (!path)
                        die("missing argument for -isystem option");
                add_pre_buffer("#add_isystem \"%s/\"\n", path);
        } else if (*next && !strcmp(arg, "idirafter")) {
                char *path = *++next;
                if (!path)
                        die("missing argument for -idirafter option");
                add_pre_buffer("#add_dirafter \"%s/\"\n", path);
        }
        return next;
}

static char **handle_switch_M(char *arg, char **next)
{
        if (!strcmp(arg, "MF") || !strcmp(arg,"MQ") || !strcmp(arg,"MT")) {
                if (!*next)
                        die("missing argument for -%s option", arg);
                return next + 1;
        }
        return next;
}

static char **handle_multiarch_dir(char *arg, char **next)
{
        multiarch_dir = *++next;
        if (!multiarch_dir)
                die("missing argument for -multiarch-dir option");
        return next;
}

static char **handle_switch_m(char *arg, char **next)
{
        if (!strcmp(arg, "m64")) {
                arch_m64 = 1;
        } else if (!strcmp(arg, "m32")) {
                arch_m64 = 0;
        } else if (!strcmp(arg, "msize-long")) {
                arch_msize_long = 1;
        } else if (!strcmp(arg, "multiarch-dir"))
                return handle_multiarch_dir(arg, next);
        return next;
}

static void handle_arch_m64_finalize(void)
{
        if (arch_m64) {
                bits_in_long = 64;
                max_int_alignment = 8;
                bits_in_pointer = 64;
                pointer_alignment = 8;
                size_t_ctype = &ulong_ctype;
                ssize_t_ctype = &long_ctype;
#ifdef __x86_64__
                add_pre_buffer("#weak_define __x86_64__ 1\n");
#endif
        }
}

static void handle_arch_msize_long_finalize(void)
{
        if (arch_msize_long) {
                size_t_ctype = &ulong_ctype;
                ssize_t_ctype = &long_ctype;
        }
}

static void handle_arch_finalize(void)
{
        handle_arch_m64_finalize();
        handle_arch_msize_long_finalize();
}


static char **handle_switch_o(char *arg, char **next)
{
        if (!strcmp (arg, "o")) {       // "-o foo"
                if (!*++next)
                        die("argument to '-o' is missing");
        }
        // else "-ofoo"

        return next;
}

static const struct warning {
        const char *name;
        int *flag;
} warnings[] = {
        { "address-space", &Waddress_space },
        { "bitwise", &Wbitwise },
        { "cast-to-as", &Wcast_to_as },
        { "cast-truncate", &Wcast_truncate },
        { "context", &Wcontext },
        { "decl", &Wdecl },
        { "declaration-after-statement", &Wdeclarationafterstatement },
        { "default-bitfield-sign", &Wdefault_bitfield_sign },
        { "designated-init", &Wdesignated_init },
        { "do-while", &Wdo_while },
        { "enum-mismatch", &Wenum_mismatch },
        { "sparse-error", &Wsparse_error },
        { "init-cstring", &Winit_cstring },
        { "non-pointer-null", &Wnon_pointer_null },
        { "old-initializer", &Wold_initializer },
        { "one-bit-signed-bitfield", &Wone_bit_signed_bitfield },
        { "paren-string", &Wparen_string },
        { "ptr-subtraction-blows", &Wptr_subtraction_blows },
        { "return-void", &Wreturn_void },
        { "shadow", &Wshadow },
        { "sizeof-bool", &Wsizeof_bool },
        { "transparent-union", &Wtransparent_union },
        { "typesign", &Wtypesign },
        { "undef", &Wundef },
        { "uninitialized", &Wuninitialized },
        { "unknown-attribute", &Wunknown_attribute },
        { "vla", &Wvla },
};

enum {
        WARNING_OFF,
        WARNING_ON,
        WARNING_FORCE_OFF
};


static char **handle_onoff_switch(char *arg, char **next, const struct warning warnings[], int n)
{
        int flag = WARNING_ON;
        char *p = arg + 1;
        unsigned i;

        if (!strcmp(p, "sparse-all")) {
                for (i = 0; i < n; i++) {
                        if (*warnings[i].flag != WARNING_FORCE_OFF && warnings[i].flag != &Wsparse_error)
                                *warnings[i].flag = WARNING_ON;
                }
        }

        // Prefixes "no" and "no-" mean to turn warning off.
        if (p[0] == 'n' && p[1] == 'o') {
                p += 2;
                if (p[0] == '-')
                        p++;
                flag = WARNING_FORCE_OFF;
        }

        for (i = 0; i < n; i++) {
                if (!strcmp(p,warnings[i].name)) {
                        *warnings[i].flag = flag;
                        return next;
                }
        }

        // Unknown.
        return NULL;
}

static char **handle_switch_W(char *arg, char **next)
{
        char ** ret = handle_onoff_switch(arg, next, warnings, ARRAY_SIZE(warnings));
        if (ret)
                return ret;

        // Unknown.
        return next;
}

static struct warning debugs[] = {
        { "entry", &dbg_entry},
        { "dead", &dbg_dead},
};


static char **handle_switch_v(char *arg, char **next)
{
        char ** ret = handle_onoff_switch(arg, next, debugs, ARRAY_SIZE(debugs));
        if (ret)
                return ret;

        // Unknown.
        do {
                verbose++;
        } while (*++arg == 'v');
        return next;
}


static void handle_onoff_switch_finalize(const struct warning warnings[], int n)
{
        unsigned i;

        for (i = 0; i < n; i++) {
                if (*warnings[i].flag == WARNING_FORCE_OFF)
                        *warnings[i].flag = WARNING_OFF;
        }
}

static void handle_switch_W_finalize(void)
{
        handle_onoff_switch_finalize(warnings, ARRAY_SIZE(warnings));

        /* default Wdeclarationafterstatement based on the C dialect */
        if (-1 == Wdeclarationafterstatement)
        {
                switch (standard)
                {
                        case STANDARD_C89:
                        case STANDARD_C94:
                                Wdeclarationafterstatement = 1;
                                break;

                        case STANDARD_C99:
                        case STANDARD_GNU89:
                        case STANDARD_GNU99:
                                Wdeclarationafterstatement = 0;
                                break;

                        default:
                                assert (0);
                }

        }
}

static void handle_switch_v_finalize(void)
{
        handle_onoff_switch_finalize(debugs, ARRAY_SIZE(debugs));
}

static char **handle_switch_U(char *arg, char **next)
{
        const char *name = arg + 1;
        add_pre_buffer ("#undef %s\n", name);
        return next;
}

static char **handle_switch_O(char *arg, char **next)
{
        int level = 1;
        if (arg[1] >= '0' && arg[1] <= '9')
                level = arg[1] - '0';
        optimize = level;
        optimize_size = arg[1] == 's';
        return next;
}

static char **handle_switch_ftabstop(char *arg, char **next)
{
        char *end;
        unsigned long val;

        if (*arg == '\0')
                die("error: missing argument to \"-ftabstop=\"");

        /* we silently ignore silly values */
        val = strtoul(arg, &end, 10);
        if (*end == '\0' && 1 <= val && val <= 100)
                tabstop = val;

        return next;
}

static char **handle_switch_f(char *arg, char **next)
{
        arg++;

        if (!strncmp(arg, "tabstop=", 8))
                return handle_switch_ftabstop(arg+8, next);

        /* handle switches w/ arguments above, boolean and only boolean below */

        if (!strncmp(arg, "no-", 3)) {
                arg += 3;
        }
        /* handle switch here.. */
        return next;
}

static char **handle_switch_G(char *arg, char **next)
{
        if (!strcmp (arg, "G") && *next)
                return next + 1; // "-G 0"
        else
                return next;     // "-G0" or (bogus) terminal "-G"
}

static char **handle_switch_a(char *arg, char **next)
{
        if (!strcmp (arg, "ansi"))
                standard = STANDARD_C89;

        return next;
}

static char **handle_switch_s(char *arg, char **next)
{
        if (!strncmp (arg, "std=", 4))
        {
                arg += 4;

                if (!strcmp (arg, "c89") ||
                    !strcmp (arg, "iso9899:1990"))
                        standard = STANDARD_C89;

                else if (!strcmp (arg, "iso9899:199409"))
                        standard = STANDARD_C94;

                else if (!strcmp (arg, "c99") ||
                         !strcmp (arg, "c9x") ||
                         !strcmp (arg, "iso9899:1999") ||
                         !strcmp (arg, "iso9899:199x"))
                        standard = STANDARD_C99;

                else if (!strcmp (arg, "gnu89"))
                        standard = STANDARD_GNU89;

                else if (!strcmp (arg, "gnu99") || !strcmp (arg, "gnu9x"))
                        standard = STANDARD_GNU99;

                else
                        die ("Unsupported C dialect");
        }

        return next;
}

static char **handle_nostdinc(char *arg, char **next)
{
        add_pre_buffer("#nostdinc\n");
        return next;
}

static char **handle_switch_n(char *arg, char **next)
{
        if (!strcmp (arg, "nostdinc"))
                return handle_nostdinc(arg, next);

        return next;
}

static char **handle_base_dir(char *arg, char **next)
{
        gcc_base_dir = *++next;
        if (!gcc_base_dir)
                die("missing argument for -gcc-base-dir option");
        return next;
}

static char **handle_switch_g(char *arg, char **next)
{
        if (!strcmp (arg, "gcc-base-dir"))
                return handle_base_dir(arg, next);

        return next;
}


static char **handle_version(char *arg, char **next)
{
        printf("%s\n", SPARSE_VERSION);
        exit(0);
}

static char **handle_param(char *arg, char **next)
{
        char *value = NULL;

        /* For now just skip any '--param=*' or '--param *' */
        if (*arg == '\0') {
                value = *++next;
        } else if (isspace((unsigned char)*arg) || *arg == '=') {
                value = ++arg;
        }

        if (!value)
                die("missing argument for --param option");

        return next;
}

struct switches {
        const char *name;
        char **(*fn)(char *, char **);
        unsigned int prefix:1;
};

static char **handle_long_options(char *arg, char **next)
{
        static struct switches cmd[] = {
                { "param", handle_param, 1 },
                { "version", handle_version },
                { NULL, NULL }
        };
        struct switches *s = cmd;

        while (s->name) {
                int optlen = strlen(s->name);
                if (!strncmp(s->name, arg, optlen + !s->prefix))
                        return s->fn(arg + optlen, next);
                s++;
        }
        return next;
}

static char **handle_switch(char *arg, char **next)
{
        switch (*arg) {
        case 'a': return handle_switch_a(arg, next);
        case 'D': return handle_switch_D(arg, next);
        case 'E': return handle_switch_E(arg, next);
        case 'f': return handle_switch_f(arg, next);
        case 'g': return handle_switch_g(arg, next);
        case 'G': return handle_switch_G(arg, next);
        case 'I': return handle_switch_I(arg, next);
        case 'i': return handle_switch_i(arg, next);
        case 'M': return handle_switch_M(arg, next);
        case 'm': return handle_switch_m(arg, next);
        case 'n': return handle_switch_n(arg, next);
        case 'o': return handle_switch_o(arg, next);
        case 'O': return handle_switch_O(arg, next);
        case 's': return handle_switch_s(arg, next);
        case 'U': return handle_switch_U(arg, next);
        case 'v': return handle_switch_v(arg, next);
        case 'W': return handle_switch_W(arg, next);
        case '-': return handle_long_options(arg + 1, next);
        default:
                break;
        }

        /*
         * Ignore unknown command line options:
         * they're probably gcc switches
         */
        return next;
}

void declare_builtin_functions(void)
{
        /* Gaah. gcc knows tons of builtin <string.h> functions */
        add_pre_buffer("extern void *__builtin_memcpy(void *, const void *, __SIZE_TYPE__);\n");
        add_pre_buffer("extern void *__builtin_mempcpy(void *, const void *, __SIZE_TYPE__);\n");
        add_pre_buffer("extern void *__builtin_memset(void *, int, __SIZE_TYPE__);\n");
        add_pre_buffer("extern int __builtin_memcmp(const void *, const void *, __SIZE_TYPE__);\n");
        add_pre_buffer("extern char *__builtin_strcat(char *, const char *);\n");
        add_pre_buffer("extern char *__builtin_strncat(char *, const char *, __SIZE_TYPE__);\n");
        add_pre_buffer("extern int __builtin_strcmp(const char *, const char *);\n");
        add_pre_buffer("extern char *__builtin_strchr(const char *, int);\n");
        add_pre_buffer("extern char *__builtin_strcpy(char *, const char *);\n");
        add_pre_buffer("extern char *__builtin_strncpy(char *, const char *, __SIZE_TYPE__);\n");
        add_pre_buffer("extern __SIZE_TYPE__ __builtin_strspn(const char *, const char *);\n");
        add_pre_buffer("extern __SIZE_TYPE__ __builtin_strcspn(const char *, const char *);\n");
        add_pre_buffer("extern char * __builtin_strpbrk(const char *, const char *);\n");
        add_pre_buffer("extern char* __builtin_stpcpy(const char *, const char*);\n");
        add_pre_buffer("extern __SIZE_TYPE__ __builtin_strlen(const char *);\n");

        /* And bitwise operations.. */
        add_pre_buffer("extern int __builtin_clz(int);\n");
        add_pre_buffer("extern int __builtin_clzl(long);\n");
        add_pre_buffer("extern int __builtin_clzll(long long);\n");
        add_pre_buffer("extern int __builtin_ctz(int);\n");
        add_pre_buffer("extern int __builtin_ctzl(long);\n");
        add_pre_buffer("extern int __builtin_ctzll(long long);\n");
        add_pre_buffer("extern int __builtin_ffs(int);\n");
        add_pre_buffer("extern int __builtin_ffsl(long);\n");
        add_pre_buffer("extern int __builtin_ffsll(long long);\n");
        add_pre_buffer("extern int __builtin_popcount(unsigned int);\n");
        add_pre_buffer("extern int __builtin_popcountl(unsigned long);\n");
        add_pre_buffer("extern int __builtin_popcountll(unsigned long long);\n");

        /* And byte swaps.. */
        add_pre_buffer("extern unsigned short ____builtin_bswap16(unsigned short);\n");
        add_pre_buffer("extern unsigned int ____builtin_bswap32(unsigned int);\n");
        add_pre_buffer("extern unsigned long long ____builtin_bswap64(unsigned long long);\n");
        add_pre_buffer("#define __sparse_constant_swab16(x) ((unsigned short)("
                       "        (((unsigned short)(x) & (unsigned short)0x00ffU) << 8) |"
                       "        (((unsigned short)(x) & (unsigned short)0xff00U) >> 8)))\n");
        add_pre_buffer("#define __sparse_constant_swab32(x) ((unsigned int)("
                       "        (((unsigned int)(x) & (unsigned int)0x000000ffUL) << 24) |"
                       "        (((unsigned int)(x) & (unsigned int)0x0000ff00UL) <<  8) |"
                       "        (((unsigned int)(x) & (unsigned int)0x00ff0000UL) >>  8) |"
                       "        (((unsigned int)(x) & (unsigned int)0xff000000UL) >> 24)))\n");
        add_pre_buffer("#define __sparse_constant_swab64(x) ((unsigned long long)("
                       "        (((unsigned long long)(x) & (unsigned long long)0x00000000000000ffULL) << 56) |"
                       "        (((unsigned long long)(x) & (unsigned long long)0x000000000000ff00ULL) << 40) |"
                       "        (((unsigned long long)(x) & (unsigned long long)0x0000000000ff0000ULL) << 24) |"
                       "        (((unsigned long long)(x) & (unsigned long long)0x00000000ff000000ULL) <<  8) |"
                       "        (((unsigned long long)(x) & (unsigned long long)0x000000ff00000000ULL) >>  8) |"
                       "        (((unsigned long long)(x) & (unsigned long long)0x0000ff0000000000ULL) >> 24) |"
                       "        (((unsigned long long)(x) & (unsigned long long)0x00ff000000000000ULL) >> 40) |"
                       "        (((unsigned long long)(x) & (unsigned long long)0xff00000000000000ULL) >> 56)))\n");
        add_pre_buffer("#define __builtin_bswap16(x)"
                       "        (__builtin_constant_p((unsigned short)(x)) ?"
                       "        __sparse_constant_swab16(x) :"
                       "        ____builtin_bswap16(x))\n");
        add_pre_buffer("#define __builtin_bswap32(x)"
                       "        (__builtin_constant_p((unsigned int)(x)) ?"
                       "        __sparse_constant_swab32(x) :"
                       "        ____builtin_bswap32(x))\n");
        add_pre_buffer("#define __builtin_bswap64(x)"
                       "        (__builtin_constant_p((unsigned long long)(x)) ?"
                       "        __sparse_constant_swab64(x) :"
                       "        ____builtin_bswap64(x))\n");

        /* And atomic memory access functions.. */
        add_pre_buffer("extern int __sync_fetch_and_add(void *, ...);\n");
        add_pre_buffer("extern int __sync_fetch_and_sub(void *, ...);\n");
        add_pre_buffer("extern int __sync_fetch_and_or(void *, ...);\n");
        add_pre_buffer("extern int __sync_fetch_and_and(void *, ...);\n");
        add_pre_buffer("extern int __sync_fetch_and_xor(void *, ...);\n");
        add_pre_buffer("extern int __sync_fetch_and_nand(void *, ...);\n");
        add_pre_buffer("extern int __sync_add_and_fetch(void *, ...);\n");
        add_pre_buffer("extern int __sync_sub_and_fetch(void *, ...);\n");
        add_pre_buffer("extern int __sync_or_and_fetch(void *, ...);\n");
        add_pre_buffer("extern int __sync_and_and_fetch(void *, ...);\n");
        add_pre_buffer("extern int __sync_xor_and_fetch(void *, ...);\n");
        add_pre_buffer("extern int __sync_nand_and_fetch(void *, ...);\n");
        add_pre_buffer("extern int __sync_bool_compare_and_swap(void *, ...);\n");
        add_pre_buffer("extern int __sync_val_compare_and_swap(void *, ...);\n");
        add_pre_buffer("extern void __sync_synchronize();\n");
        add_pre_buffer("extern int __sync_lock_test_and_set(void *, ...);\n");
        add_pre_buffer("extern void __sync_lock_release(void *, ...);\n");

        /* And some random ones.. */
        add_pre_buffer("extern void *__builtin_return_address(unsigned int);\n");
        add_pre_buffer("extern void *__builtin_extract_return_addr(void *);\n");
        add_pre_buffer("extern void *__builtin_frame_address(unsigned int);\n");
        add_pre_buffer("extern void __builtin_trap(void);\n");
        add_pre_buffer("extern void *__builtin_alloca(__SIZE_TYPE__);\n");
        add_pre_buffer("extern void __builtin_prefetch (const void *, ...);\n");
        add_pre_buffer("extern long __builtin_alpha_extbl(long, long);\n");
        add_pre_buffer("extern long __builtin_alpha_extwl(long, long);\n");
        add_pre_buffer("extern long __builtin_alpha_insbl(long, long);\n");
        add_pre_buffer("extern long __builtin_alpha_inswl(long, long);\n");
        add_pre_buffer("extern long __builtin_alpha_insql(long, long);\n");
        add_pre_buffer("extern long __builtin_alpha_inslh(long, long);\n");
        add_pre_buffer("extern long __builtin_alpha_cmpbge(long, long);\n");
        add_pre_buffer("extern long __builtin_labs(long);\n");
        add_pre_buffer("extern double __builtin_fabs(double);\n");
        add_pre_buffer("extern __SIZE_TYPE__ __builtin_va_arg_pack_len(void);\n");

        /* Add Blackfin-specific stuff */
        add_pre_buffer(
                "#ifdef __bfin__\n"
                "extern void __builtin_bfin_csync(void);\n"
                "extern void __builtin_bfin_ssync(void);\n"
                "extern int __builtin_bfin_norm_fr1x32(int);\n"
                "#endif\n"
        );

        /* And some floating point stuff.. */
        add_pre_buffer("extern int __builtin_isgreater(float, float);\n");
        add_pre_buffer("extern int __builtin_isgreaterequal(float, float);\n");
        add_pre_buffer("extern int __builtin_isless(float, float);\n");
        add_pre_buffer("extern int __builtin_islessequal(float, float);\n");
        add_pre_buffer("extern int __builtin_islessgreater(float, float);\n");
        add_pre_buffer("extern int __builtin_isunordered(float, float);\n");

        /* And some INFINITY / NAN stuff.. */
        add_pre_buffer("extern double __builtin_huge_val(void);\n");
        add_pre_buffer("extern float __builtin_huge_valf(void);\n");
        add_pre_buffer("extern long double __builtin_huge_vall(void);\n");
        add_pre_buffer("extern double __builtin_inf(void);\n");
        add_pre_buffer("extern float __builtin_inff(void);\n");
        add_pre_buffer("extern long double __builtin_infl(void);\n");
        add_pre_buffer("extern double __builtin_nan(const char *);\n");
        add_pre_buffer("extern float __builtin_nanf(const char *);\n");
        add_pre_buffer("extern long double __builtin_nanl(const char *);\n");

        /* And some __FORTIFY_SOURCE ones.. */
        add_pre_buffer ("extern __SIZE_TYPE__ __builtin_object_size(const void *, int);\n");
        add_pre_buffer ("extern void * __builtin___memcpy_chk(void *, const void *, __SIZE_TYPE__, __SIZE_TYPE__);\n");
        add_pre_buffer ("extern void * __builtin___memmove_chk(void *, const void *, __SIZE_TYPE__, __SIZE_TYPE__);\n");
        add_pre_buffer ("extern void * __builtin___mempcpy_chk(void *, const void *, __SIZE_TYPE__, __SIZE_TYPE__);\n");
        add_pre_buffer ("extern void * __builtin___memset_chk(void *, int, __SIZE_TYPE__, __SIZE_TYPE__);\n");
        add_pre_buffer ("extern int __builtin___sprintf_chk(char *, int, __SIZE_TYPE__, const char *, ...);\n");
        add_pre_buffer ("extern int __builtin___snprintf_chk(char *, __SIZE_TYPE__, int , __SIZE_TYPE__, const char *, ...);\n");
        add_pre_buffer ("extern char * __builtin___stpcpy_chk(char *, const char *, __SIZE_TYPE__);\n");
        add_pre_buffer ("extern char * __builtin___strcat_chk(char *, const char *, __SIZE_TYPE__);\n");
        add_pre_buffer ("extern char * __builtin___strcpy_chk(char *, const char *, __SIZE_TYPE__);\n");
        add_pre_buffer ("extern char * __builtin___strncat_chk(char *, const char *, __SIZE_TYPE__, __SIZE_TYPE__);\n");
        add_pre_buffer ("extern char * __builtin___strncpy_chk(char *, const char *, __SIZE_TYPE__, __SIZE_TYPE__);\n");
        add_pre_buffer ("extern int __builtin___vsprintf_chk(char *, int, __SIZE_TYPE__, const char *, __builtin_va_list);\n");
        add_pre_buffer ("extern int __builtin___vsnprintf_chk(char *, __SIZE_TYPE__, int, __SIZE_TYPE__, const char *, __builtin_va_list ap);\n");
        add_pre_buffer ("extern void __builtin_unreachable(void);\n");
}

void create_builtin_stream(void)
{
        add_pre_buffer("#weak_define __GNUC__ %d\n", gcc_major);
        add_pre_buffer("#weak_define __GNUC_MINOR__ %d\n", gcc_minor);
        add_pre_buffer("#weak_define __GNUC_PATCHLEVEL__ %d\n", gcc_patchlevel);

        /* add the multiarch include directories, if any */
        if (multiarch_dir && *multiarch_dir) {
                add_pre_buffer("#add_system \"/usr/include/%s\"\n", multiarch_dir);
                add_pre_buffer("#add_system \"/usr/local/include/%s\"\n", multiarch_dir);
        }

        /* We add compiler headers path here because we have to parse
         * the arguments to get it, falling back to default. */
        add_pre_buffer("#add_system \"%s/include\"\n", gcc_base_dir);
        add_pre_buffer("#add_system \"%s/include-fixed\"\n", gcc_base_dir);

        add_pre_buffer("#define __extension__\n");
        add_pre_buffer("#define __pragma__\n");

        // gcc defines __SIZE_TYPE__ to be size_t.  For linux/i86 and
        // solaris/sparc that is really "unsigned int" and for linux/x86_64
        // it is "long unsigned int".  In either case we can probably
        // get away with this.  We need the #weak_define as cgcc will define
        // the right __SIZE_TYPE__.
        if (size_t_ctype == &ulong_ctype)
                add_pre_buffer("#weak_define __SIZE_TYPE__ long unsigned int\n");
        else
                add_pre_buffer("#weak_define __SIZE_TYPE__ unsigned int\n");
        add_pre_buffer("#weak_define __STDC__ 1\n");

        switch (standard)
        {
                case STANDARD_C89:
                        add_pre_buffer("#weak_define __STRICT_ANSI__\n");
                        break;

                case STANDARD_C94:
                        add_pre_buffer("#weak_define __STDC_VERSION__ 199409L\n");
                        add_pre_buffer("#weak_define __STRICT_ANSI__\n");
                        break;

                case STANDARD_C99:
                        add_pre_buffer("#weak_define __STDC_VERSION__ 199901L\n");
                        add_pre_buffer("#weak_define __STRICT_ANSI__\n");
                        break;

                case STANDARD_GNU89:
                        break;

                case STANDARD_GNU99:
                        add_pre_buffer("#weak_define __STDC_VERSION__ 199901L\n");
                        break;

                default:
                        assert (0);
        }

        add_pre_buffer("#define __builtin_stdarg_start(a,b) ((a) = (__builtin_va_list)(&(b)))\n");
        add_pre_buffer("#define __builtin_va_start(a,b) ((a) = (__builtin_va_list)(&(b)))\n");
        add_pre_buffer("#define __builtin_ms_va_start(a,b) ((a) = (__builtin_ms_va_list)(&(b)))\n");
        add_pre_buffer("#define __builtin_va_arg(arg,type)  ({ type __va_arg_ret = *(type *)(arg); arg += sizeof(type); __va_arg_ret; })\n");
        add_pre_buffer("#define __builtin_va_alist (*(void *)0)\n");
        add_pre_buffer("#define __builtin_va_arg_incr(x) ((x) + 1)\n");
        add_pre_buffer("#define __builtin_va_copy(dest, src) ({ dest = src; (void)0; })\n");
        add_pre_buffer("#define __builtin_ms_va_copy(dest, src) ({ dest = src; (void)0; })\n");
        add_pre_buffer("#define __builtin_va_end(arg)\n");
        add_pre_buffer("#define __builtin_ms_va_end(arg)\n");
        add_pre_buffer("#define __builtin_va_arg_pack()\n");

        /* FIXME! We need to do these as special magic macros at expansion time! */
        add_pre_buffer("#define __BASE_FILE__ \"base_file.c\"\n");

        if (optimize)
                add_pre_buffer("#define __OPTIMIZE__ 1\n");
        if (optimize_size)
                add_pre_buffer("#define __OPTIMIZE_SIZE__ 1\n");

        /* GCC defines these for limits.h */
        add_pre_buffer("#weak_define __SHRT_MAX__ " STRINGIFY(__SHRT_MAX__) "\n");
        add_pre_buffer("#weak_define __SCHAR_MAX__ " STRINGIFY(__SCHAR_MAX__) "\n");
        add_pre_buffer("#weak_define __INT_MAX__ " STRINGIFY(__INT_MAX__) "\n");
        add_pre_buffer("#weak_define __LONG_MAX__ " STRINGIFY(__LONG_MAX__) "\n");
        add_pre_buffer("#weak_define __LONG_LONG_MAX__ " STRINGIFY(__LONG_LONG_MAX__) "\n");
        add_pre_buffer("#weak_define __WCHAR_MAX__ " STRINGIFY(__WCHAR_MAX__) "\n");
        add_pre_buffer("#weak_define __SIZEOF_POINTER__ " STRINGIFY(__SIZEOF_POINTER__) "\n");
        add_pre_buffer("#weak_define __CHAR_BIT__ " STRINGIFY(__CHAR_BIT__) "\n");
}

static struct symbol_list *sparse_tokenstream(struct token *token)
{
        // Preprocess the stream
        token = preprocess(token);

        if (preprocess_only) {
                while (!eof_token(token)) {
                        int prec = 1;
                        struct token *next = token->next;
                        const char *separator = "";
                        if (next->pos.whitespace)
                                separator = " ";
                        if (next->pos.newline) {
                                separator = "\n\t\t\t\t\t";
                                prec = next->pos.pos;
                                if (prec > 4)
                                        prec = 4;
                        }
                        printf("%s%.*s", show_token(token), prec, separator);
                        token = next;
                }
                putchar('\n');

                return NULL;
        }

        // Parse the resulting C code
        while (!eof_token(token))
                token = external_declaration(token, &translation_unit_used_list);
        return translation_unit_used_list;
}

static struct symbol_list *sparse_file(const char *filename)
{
        int fd;
        struct token *token;

        if (strcmp (filename, "-") == 0) {
                fd = 0;
        } else {
                fd = open(filename, O_RDONLY);
                if (fd < 0)
                        die("No such file: %s", filename);
        }

        // Tokenize the input stream
        token = tokenize(filename, fd, NULL, includepath);
        close(fd);

        return sparse_tokenstream(token);
}

/*
 * This handles the "-include" directive etc: we're in global
 * scope, and all types/macros etc will affect all the following
 * files.
 *
 * NOTE NOTE NOTE! "#undef" of anything in this stage will
 * affect all subsequent files too, i.e. we can have non-local
 * behaviour between files!
 */
static struct symbol_list *sparse_initial(void)
{
        int i;

        // Prepend any "include" file to the stream.
        // We're in global scope, it will affect all files!
        for (i = 0; i < cmdline_include_nr; i++)
                add_pre_buffer("#argv_include \"%s\"\n", cmdline_include[i]);

        return sparse_tokenstream(pre_buffer_begin);
}

struct symbol_list *sparse_initialize(int argc, char **argv, struct string_list **filelist)
{
        char **args;
        struct symbol_list *list;

        // Initialize symbol stream first, so that we can add defines etc
        init_symbols();

        args = argv;
        for (;;) {
                char *arg = *++args;
                if (!arg)
                        break;

                if (arg[0] == '-' && arg[1]) {
                        args = handle_switch(arg+1, args);
                        continue;
                }
                add_ptr_list_notag(filelist, arg);
        }
        handle_switch_W_finalize();
        handle_switch_v_finalize();

        handle_arch_finalize();

        list = NULL;
        if (!ptr_list_empty(filelist)) {
                // Initialize type system
                init_ctype();

                create_builtin_stream();
                add_pre_buffer("#define __CHECKER__ 1\n");
                if (!preprocess_only)
                        declare_builtin_functions();

                list = sparse_initial();

                /*
                 * Protect the initial token allocations, since
                 * they need to survive all the others
                 */
                protect_token_alloc();
        }
        return list;
}

struct symbol_list * sparse_keep_tokens(char *filename)
{
        struct symbol_list *res;

        /* Clear previous symbol list */
        translation_unit_used_list = NULL;

        new_file_scope();
        res = sparse_file(filename);

        /* And return it */
        return res;
}


struct symbol_list * __sparse(char *filename)
{
        struct symbol_list *res;

        res = sparse_keep_tokens(filename);

        /* Drop the tokens for this file after parsing */
        clear_token_alloc();

        /* And return it */
        return res;
}

struct symbol_list * sparse(char *filename)
{
        struct symbol_list *res = __sparse(filename);

        /* Evaluate the complete symbol list */
        evaluate_symbol_list(res);

        return res;
}