glsl/glcpp/glcpp-parse.y

%{
/*
 * Copyright © 2010 Intel Corporation
 *
 * 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 (including the next
 * paragraph) 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 <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <inttypes.h>

#include "glcpp.h"
#include "main/mtypes.h"
#include "util/strndup.h"

const char *
_mesa_lookup_shader_include(struct gl_context *ctx, char *path,
                            bool error_check);

size_t
_mesa_get_shader_include_cursor(struct gl_shared_state *shared);

void
_mesa_set_shader_include_cursor(struct gl_shared_state *shared, size_t cursor);

static void
yyerror(YYLTYPE *locp, glcpp_parser_t *parser, const char *error);

static void
_define_object_macro(glcpp_parser_t *parser,
                     YYLTYPE *loc,
                     const char *macro,
                     token_list_t *replacements);

static void
_define_function_macro(glcpp_parser_t *parser,
                       YYLTYPE *loc,
                       const char *macro,
                       string_list_t *parameters,
                       token_list_t *replacements);

static string_list_t *
_string_list_create(glcpp_parser_t *parser);

static void
_string_list_append_item(glcpp_parser_t *parser, string_list_t *list,
                         const char *str);

static int
_string_list_contains(string_list_t *list, const char *member, int *index);

static const char *
_string_list_has_duplicate(string_list_t *list);

static int
_string_list_length(string_list_t *list);

static int
_string_list_equal(string_list_t *a, string_list_t *b);

static argument_list_t *
_argument_list_create(glcpp_parser_t *parser);

static void
_argument_list_append(glcpp_parser_t *parser, argument_list_t *list,
                      token_list_t *argument);

static int
_argument_list_length(argument_list_t *list);

static token_list_t *
_argument_list_member_at(argument_list_t *list, int index);

static token_t *
_token_create_str(glcpp_parser_t *parser, int type, char *str);

static token_t *
_token_create_ival(glcpp_parser_t *parser, int type, int ival);

static token_list_t *
_token_list_create(glcpp_parser_t *parser);

static void
_token_list_prepend(glcpp_parser_t *parser, token_list_t *list, token_t *token);

static void
_token_list_append(glcpp_parser_t *parser, token_list_t *list, token_t *token);

static void
_token_list_append_list(token_list_t *list, token_list_t *tail);

static int
_token_list_equal_ignoring_space(token_list_t *a, token_list_t *b);

static void
_parser_active_list_push(glcpp_parser_t *parser, const char *identifier,
                         token_node_t *marker);

static void
_parser_active_list_pop(glcpp_parser_t *parser);

static int
_parser_active_list_contains(glcpp_parser_t *parser, const char *identifier);

typedef enum {
   EXPANSION_MODE_IGNORE_DEFINED,
   EXPANSION_MODE_EVALUATE_DEFINED
} expansion_mode_t;

/* Expand list, and begin lexing from the result (after first
 * prefixing a token of type 'head_token_type').
 */
static void
_glcpp_parser_expand_and_lex_from(glcpp_parser_t *parser, int head_token_type,
                                  token_list_t *list, expansion_mode_t mode);

/* Perform macro expansion in-place on the given list. */
static void
_glcpp_parser_expand_token_list(glcpp_parser_t *parser, token_list_t *list,
                                expansion_mode_t mode);

static void
_glcpp_parser_print_expanded_token_list(glcpp_parser_t *parser,
                                        token_list_t *list);

static void
_glcpp_parser_skip_stack_push_if(glcpp_parser_t *parser, YYLTYPE *loc,
                                 int condition);

static void
_glcpp_parser_skip_stack_change_if(glcpp_parser_t *parser, YYLTYPE *loc,
                                   const char *type, int condition);

static void
_glcpp_parser_skip_stack_pop(glcpp_parser_t *parser, YYLTYPE *loc);

static void
_glcpp_parser_handle_version_declaration(glcpp_parser_t *parser, intmax_t version,
                                         const char *ident, bool explicitly_set);

static int
glcpp_parser_lex(YYSTYPE *yylval, YYLTYPE *yylloc, glcpp_parser_t *parser);

static void
glcpp_parser_lex_from(glcpp_parser_t *parser, token_list_t *list);

struct define_include {
   glcpp_parser_t *parser;
   YYLTYPE *loc;
};

static void
glcpp_parser_copy_defines(const void *key, void *data, void *closure);

static void
add_builtin_define(glcpp_parser_t *parser, const char *name, int value);

%}

%pure-parser
%error-verbose

%locations
%initial-action {
   @$.first_line = 1;
   @$.first_column = 1;
   @$.last_line = 1;
   @$.last_column = 1;
   @$.source = 0;
}

%parse-param {glcpp_parser_t *parser}
%lex-param {glcpp_parser_t *parser}

%expect 0

        /* We use HASH_TOKEN, DEFINE_TOKEN and VERSION_TOKEN (as opposed to
         * HASH, DEFINE, and VERSION) to avoid conflicts with other symbols,
         * (such as the <HASH> and <DEFINE> start conditions in the lexer). */
%token DEFINED ELIF_EXPANDED HASH_TOKEN DEFINE_TOKEN FUNC_IDENTIFIER OBJ_IDENTIFIER ELIF ELSE ENDIF ERROR_TOKEN IF IFDEF IFNDEF LINE PRAGMA UNDEF VERSION_TOKEN GARBAGE IDENTIFIER IF_EXPANDED INTEGER INTEGER_STRING LINE_EXPANDED NEWLINE OTHER PLACEHOLDER SPACE PLUS_PLUS MINUS_MINUS PATH INCLUDE
%token PASTE
%type <ival> INTEGER operator SPACE integer_constant version_constant
%type <expression_value> expression
%type <str> IDENTIFIER FUNC_IDENTIFIER OBJ_IDENTIFIER INTEGER_STRING OTHER ERROR_TOKEN PRAGMA PATH INCLUDE
%type <string_list> identifier_list
%type <token> preprocessing_token
%type <token_list> pp_tokens replacement_list text_line
%left OR
%left AND
%left '|'
%left '^'
%left '&'
%left EQUAL NOT_EQUAL
%left '<' '>' LESS_OR_EQUAL GREATER_OR_EQUAL
%left LEFT_SHIFT RIGHT_SHIFT
%left '+' '-'
%left '*' '/' '%'
%right UNARY

%debug

%%

input:
   /* empty */
|  input line
;

line:
   control_line
|  SPACE control_line
|  text_line {
      _glcpp_parser_print_expanded_token_list (parser, $1);
      _mesa_string_buffer_append_char(parser->output, '\n');
   }
|  expanded_line
;

expanded_line:
   IF_EXPANDED expression NEWLINE {
      if (parser->is_gles && $2.undefined_macro)
         glcpp_error(& @1, parser, "undefined macro %s in expression (illegal in GLES)", $2.undefined_macro);
      _glcpp_parser_skip_stack_push_if (parser, & @1, $2.value);
   }
|  ELIF_EXPANDED expression NEWLINE {
      if (parser->is_gles && $2.undefined_macro)
         glcpp_error(& @1, parser, "undefined macro %s in expression (illegal in GLES)", $2.undefined_macro);
      _glcpp_parser_skip_stack_change_if (parser, & @1, "elif", $2.value);
   }
|  LINE_EXPANDED integer_constant NEWLINE {
      parser->has_new_line_number = 1;
      parser->new_line_number = $2;
      _mesa_string_buffer_printf(parser->output, "#line %" PRIiMAX "\n", $2);
   }
|  LINE_EXPANDED integer_constant integer_constant NEWLINE {
      parser->has_new_line_number = 1;
      parser->new_line_number = $2;
      parser->has_new_source_number = 1;
      parser->new_source_number = $3;
      _mesa_string_buffer_printf(parser->output,
                  "#line %" PRIiMAX " %" PRIiMAX "\n",
                   $2, $3);
   }
|  LINE_EXPANDED integer_constant PATH NEWLINE {
      parser->has_new_line_number = 1;
      parser->new_line_number = $2;
      _mesa_string_buffer_printf(parser->output,
                  "#line %" PRIiMAX " %s\n",
                   $2, $3);
   }
;

define:
   OBJ_IDENTIFIER replacement_list NEWLINE {
      _define_object_macro (parser, & @1, $1, $2);
   }
|  FUNC_IDENTIFIER '(' ')' replacement_list NEWLINE {
      _define_function_macro (parser, & @1, $1, NULL, $4);
   }
|  FUNC_IDENTIFIER '(' identifier_list ')' replacement_list NEWLINE {
      _define_function_macro (parser, & @1, $1, $3, $5);
   }
;

control_line:
   control_line_success {
      _mesa_string_buffer_append_char(parser->output, '\n');
   }
|  control_line_error
|  HASH_TOKEN LINE pp_tokens NEWLINE {

      if (parser->skip_stack == NULL ||
          parser->skip_stack->type == SKIP_NO_SKIP)
      {
         _glcpp_parser_expand_and_lex_from (parser,
                        LINE_EXPANDED, $3,
                        EXPANSION_MODE_IGNORE_DEFINED);
      }
   }
;

control_line_success:
   HASH_TOKEN DEFINE_TOKEN define
|  HASH_TOKEN UNDEF IDENTIFIER NEWLINE {
      struct hash_entry *entry;

      /* Section 3.4 (Preprocessor) of the GLSL ES 3.00 spec says:
       *
       *    It is an error to undefine or to redefine a built-in
       *    (pre-defined) macro name.
       *
       * The GLSL ES 1.00 spec does not contain this text, but
       * dEQP's preprocess test in GLES2 checks for it.
       *
       * Section 3.3 (Preprocessor) revision 7, of the GLSL 4.50
       * spec says:
       *
       *    By convention, all macro names containing two consecutive
       *    underscores ( __ ) are reserved for use by underlying
       *    software layers. Defining or undefining such a name
       *    in a shader does not itself result in an error, but may
       *    result in unintended behaviors that stem from having
       *    multiple definitions of the same name. All macro names
       *    prefixed with "GL_" (...) are also reseved, and defining
       *    such a name results in a compile-time error.
       *
       * The code below implements the same checks as GLSLang.
       */
      if (strncmp("GL_", $3, 3) == 0)
         glcpp_error(& @1, parser, "Built-in (pre-defined)"
                " names beginning with GL_ cannot be undefined.");
      else if (strstr($3, "__") != NULL) {
         if (parser->is_gles
             && parser->version >= 300
             && (strcmp("__LINE__", $3) == 0
            || strcmp("__FILE__", $3) == 0
            || strcmp("__VERSION__", $3) == 0)) {
            glcpp_error(& @1, parser, "Built-in (pre-defined)"
                   " names cannot be undefined.");
         } else if (parser->is_gles && parser->version <= 300) {
            glcpp_error(& @1, parser,
                   " names containing consecutive underscores"
                   " are reserved.");
         } else {
            glcpp_warning(& @1, parser,
                     " names containing consecutive underscores"
                     " are reserved.");
         }
      }

      entry = _mesa_hash_table_search (parser->defines, $3);
      if (entry) {
         _mesa_hash_table_remove (parser->defines, entry);
      }
   }
|  HASH_TOKEN INCLUDE NEWLINE {
      size_t include_cursor = _mesa_get_shader_include_cursor(parser->gl_ctx->Shared);

      /* Remove leading and trailing "" or <> */
      char *start = strchr($2, '"');
      if (!start) {
         _mesa_set_shader_include_cursor(parser->gl_ctx->Shared, 0);
         start = strchr($2, '<');
      }
      char *path = strndup(start + 1, strlen(start + 1) - 1);

      const char *shader =
         _mesa_lookup_shader_include(parser->gl_ctx, path, false);
      free(path);

      if (!shader)
         glcpp_error(&@1, parser, "%s not found", $2);
      else {
         /* Create a temporary parser with the same settings */
         glcpp_parser_t *tmp_parser =
            glcpp_parser_create(parser->gl_ctx, parser->extensions, parser->state);
         tmp_parser->version_set = true;
         tmp_parser->version = parser->version;

         /* Set the shader source and run the lexer */
         glcpp_lex_set_source_string(tmp_parser, shader);

         /* Copy any existing define macros to the temporary
          * shade include parser.
          */
         struct define_include di;
         di.parser = tmp_parser;
         di.loc = &@1;

         hash_table_call_foreach(parser->defines,
                  glcpp_parser_copy_defines,
                  &di);

         /* Print out '#include' to the glsl parser. We do this
          * so that it can do the error checking require to
          * make sure the ARB_shading_language_include
          * extension is enabled.
          */
         _mesa_string_buffer_printf(parser->output, "#include\n");

         /* Parse the include string before adding to the
          * preprocessor output.
          */
         glcpp_parser_parse(tmp_parser);
         _mesa_string_buffer_printf(parser->info_log, "%s",
                     tmp_parser->info_log->buf);
         _mesa_string_buffer_printf(parser->output, "%s",
                     tmp_parser->output->buf);

         /* Copy any new define macros to the parent parser
          * and steal the memory of our temp parser so we don't
          * free these new defines before they are no longer
          * needed.
          */
         di.parser = parser;
         di.loc = &@1;
         ralloc_steal(parser, tmp_parser);

         hash_table_call_foreach(tmp_parser->defines,
                  glcpp_parser_copy_defines,
                  &di);

         /* Destroy tmp parser memory we no longer need */
         glcpp_lex_destroy(tmp_parser->scanner);
         _mesa_hash_table_destroy(tmp_parser->defines, NULL);
      }

      _mesa_set_shader_include_cursor(parser->gl_ctx->Shared, include_cursor);
   }
|  HASH_TOKEN IF pp_tokens NEWLINE {
      /* Be careful to only evaluate the 'if' expression if
       * we are not skipping. When we are skipping, we
       * simply push a new 0-valued 'if' onto the skip
       * stack.
       *
       * This avoids generating diagnostics for invalid
       * expressions that are being skipped. */
      if (parser->skip_stack == NULL ||
          parser->skip_stack->type == SKIP_NO_SKIP)
      {
         _glcpp_parser_expand_and_lex_from (parser,
                        IF_EXPANDED, $3,
                        EXPANSION_MODE_EVALUATE_DEFINED);
      }
      else
      {
         _glcpp_parser_skip_stack_push_if (parser, & @1, 0);
         parser->skip_stack->type = SKIP_TO_ENDIF;
      }
   }
|  HASH_TOKEN IF NEWLINE {
      /* #if without an expression is only an error if we
       *  are not skipping */
      if (parser->skip_stack == NULL ||
          parser->skip_stack->type == SKIP_NO_SKIP)
      {
         glcpp_error(& @1, parser, "#if with no expression");
      }
      _glcpp_parser_skip_stack_push_if (parser, & @1, 0);
   }
|  HASH_TOKEN IFDEF IDENTIFIER junk NEWLINE {
      struct hash_entry *entry =
            _mesa_hash_table_search(parser->defines, $3);
      macro_t *macro = entry ? entry->data : NULL;
      _glcpp_parser_skip_stack_push_if (parser, & @1, macro != NULL);
   }
|  HASH_TOKEN IFNDEF IDENTIFIER junk NEWLINE {
      struct hash_entry *entry =
            _mesa_hash_table_search(parser->defines, $3);
      macro_t *macro = entry ? entry->data : NULL;
      _glcpp_parser_skip_stack_push_if (parser, & @3, macro == NULL);
   }
|  HASH_TOKEN ELIF pp_tokens NEWLINE {
      /* Be careful to only evaluate the 'elif' expression
       * if we are not skipping. When we are skipping, we
       * simply change to a 0-valued 'elif' on the skip
       * stack.
       *
       * This avoids generating diagnostics for invalid
       * expressions that are being skipped. */
      if (parser->skip_stack &&
          parser->skip_stack->type == SKIP_TO_ELSE)
      {
         _glcpp_parser_expand_and_lex_from (parser,
                        ELIF_EXPANDED, $3,
                        EXPANSION_MODE_EVALUATE_DEFINED);
      }
      else if (parser->skip_stack &&
          parser->skip_stack->has_else)
      {
         glcpp_error(& @1, parser, "#elif after #else");
      }
      else
      {
         _glcpp_parser_skip_stack_change_if (parser, & @1,
                         "elif", 0);
      }
   }
|  HASH_TOKEN ELIF NEWLINE {
      /* #elif without an expression is an error unless we
       * are skipping. */
      if (parser->skip_stack &&
          parser->skip_stack->type == SKIP_TO_ELSE)
      {
         glcpp_error(& @1, parser, "#elif with no expression");
      }
      else if (parser->skip_stack &&
          parser->skip_stack->has_else)
      {
         glcpp_error(& @1, parser, "#elif after #else");
      }
      else
      {
         _glcpp_parser_skip_stack_change_if (parser, & @1,
                         "elif", 0);
         glcpp_warning(& @1, parser, "ignoring illegal #elif without expression");
      }
   }
|  HASH_TOKEN ELSE { parser->lexing_directive = 1; } NEWLINE {
      if (parser->skip_stack &&
          parser->skip_stack->has_else)
      {
         glcpp_error(& @1, parser, "multiple #else");
      }
      else
      {
         _glcpp_parser_skip_stack_change_if (parser, & @1, "else", 1);
         if (parser->skip_stack)
            parser->skip_stack->has_else = true;
      }
   }
|  HASH_TOKEN ENDIF {
      _glcpp_parser_skip_stack_pop (parser, & @1);
   } NEWLINE
|  HASH_TOKEN VERSION_TOKEN version_constant NEWLINE {
      if (parser->version_set) {
         glcpp_error(& @1, parser, "#version must appear on the first line");
      }
      _glcpp_parser_handle_version_declaration(parser, $3, NULL, true);
   }
|  HASH_TOKEN VERSION_TOKEN version_constant IDENTIFIER NEWLINE {
      if (parser->version_set) {
         glcpp_error(& @1, parser, "#version must appear on the first line");
      }
      _glcpp_parser_handle_version_declaration(parser, $3, $4, true);
   }
|  HASH_TOKEN NEWLINE {
      glcpp_parser_resolve_implicit_version(parser);
   }
|  HASH_TOKEN PRAGMA NEWLINE {
      _mesa_string_buffer_printf(parser->output, "#%s", $2);
   }
;

control_line_error:
   HASH_TOKEN ERROR_TOKEN NEWLINE {
      glcpp_error(& @1, parser, "#%s", $2);
   }
|  HASH_TOKEN DEFINE_TOKEN NEWLINE {
      glcpp_error (& @1, parser, "#define without macro name");
   }
|  HASH_TOKEN GARBAGE pp_tokens NEWLINE  {
      glcpp_error (& @1, parser, "Illegal non-directive after #");
   }
;

integer_constant:
   INTEGER_STRING {
      /* let strtoll detect the base */
      $$ = strtoll ($1, NULL, 0);
   }
|  INTEGER {
      $$ = $1;
   }

version_constant:
   INTEGER_STRING {
      /* Both octal and hexadecimal constants begin with 0. */
      if ($1[0] == '0' && $1[1] != '\0') {
      glcpp_error(&@1, parser, "invalid #version \"%s\" (not a decimal constant)", $1);
      $$ = 0;
      } else {
      $$ = strtoll($1, NULL, 10);
      }
   }

expression:
   integer_constant {
      $$.value = $1;
      $$.undefined_macro = NULL;
   }
|  IDENTIFIER {
      $$.value = 0;
      if (parser->is_gles)
         $$.undefined_macro = linear_strdup(parser->linalloc, $1);
      else
         $$.undefined_macro = NULL;
   }
|  expression OR expression {
      $$.value = $1.value || $3.value;

      /* Short-circuit: Only flag undefined from right side
       * if left side evaluates to false.
       */
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else if (! $1.value)
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression AND expression {
      $$.value = $1.value && $3.value;

      /* Short-circuit: Only flag undefined from right-side
       * if left side evaluates to true.
       */
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else if ($1.value)
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression '|' expression {
      $$.value = $1.value | $3.value;
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression '^' expression {
      $$.value = $1.value ^ $3.value;
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression '&' expression {
      $$.value = $1.value & $3.value;
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression NOT_EQUAL expression {
      $$.value = $1.value != $3.value;
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression EQUAL expression {
      $$.value = $1.value == $3.value;
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression GREATER_OR_EQUAL expression {
      $$.value = $1.value >= $3.value;
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression LESS_OR_EQUAL expression {
      $$.value = $1.value <= $3.value;
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression '>' expression {
      $$.value = $1.value > $3.value;
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression '<' expression {
      $$.value = $1.value < $3.value;
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression RIGHT_SHIFT expression {
      $$.value = $1.value >> $3.value;
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression LEFT_SHIFT expression {
      $$.value = $1.value << $3.value;
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression '-' expression {
      $$.value = $1.value - $3.value;
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression '+' expression {
      $$.value = $1.value + $3.value;
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression '%' expression {
      if ($3.value == 0) {
         yyerror (& @1, parser,
             "zero modulus in preprocessor directive");
      } else {
         $$.value = $1.value % $3.value;
      }
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression '/' expression {
      if ($3.value == 0) {
         yyerror (& @1, parser,
             "division by 0 in preprocessor directive");
      } else {
         $$.value = $1.value / $3.value;
      }
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  expression '*' expression {
      $$.value = $1.value * $3.value;
      if ($1.undefined_macro)
         $$.undefined_macro = $1.undefined_macro;
                else
         $$.undefined_macro = $3.undefined_macro;
   }
|  '!' expression %prec UNARY {
      $$.value = ! $2.value;
      $$.undefined_macro = $2.undefined_macro;
   }
|  '~' expression %prec UNARY {
      $$.value = ~ $2.value;
      $$.undefined_macro = $2.undefined_macro;
   }
|  '-' expression %prec UNARY {
      $$.value = - $2.value;
      $$.undefined_macro = $2.undefined_macro;
   }
|  '+' expression %prec UNARY {
      $$.value = + $2.value;
      $$.undefined_macro = $2.undefined_macro;
   }
|  '(' expression ')' {
      $$ = $2;
   }
;

identifier_list:
   IDENTIFIER {
      $$ = _string_list_create (parser);
      _string_list_append_item (parser, $$, $1);
   }
|  identifier_list ',' IDENTIFIER {
      $$ = $1;
      _string_list_append_item (parser, $$, $3);
   }
;

text_line:
   NEWLINE { $$ = NULL; }
|  pp_tokens NEWLINE
;

replacement_list:
   /* empty */ { $$ = NULL; }
|  pp_tokens
;

junk:
   /* empty */
|  pp_tokens {
      if (parser->gl_ctx->Const.AllowExtraPPTokens)
         glcpp_warning(&@1, parser, "extra tokens at end of directive");
      else
         glcpp_error(&@1, parser, "extra tokens at end of directive");

      (void)yynerrs;
   }
;

pp_tokens:
   preprocessing_token {
      parser->space_tokens = 1;
      $$ = _token_list_create (parser);
      _token_list_append (parser, $$, $1);
   }
|  pp_tokens preprocessing_token {
      $$ = $1;
      _token_list_append (parser, $$, $2);
   }
;

preprocessing_token:
   IDENTIFIER {
      $$ = _token_create_str (parser, IDENTIFIER, $1);
      $$->location = yylloc;
   }
|  INTEGER_STRING {
      $$ = _token_create_str (parser, INTEGER_STRING, $1);
      $$->location = yylloc;
   }
|  PATH {
      $$ = _token_create_str (parser, PATH, $1);
      $$->location = yylloc;
   }
|  operator {
      $$ = _token_create_ival (parser, $1, $1);
      $$->location = yylloc;
   }
|  DEFINED {
      $$ = _token_create_ival (parser, DEFINED, DEFINED);
      $$->location = yylloc;
   }
|  OTHER {
      $$ = _token_create_str (parser, OTHER, $1);
      $$->location = yylloc;
   }
|  SPACE {
      $$ = _token_create_ival (parser, SPACE, SPACE);
      $$->location = yylloc;
   }
;

operator:
   '['               { $$ = '['; }
|  ']'               { $$ = ']'; }
|  '('               { $$ = '('; }
|  ')'               { $$ = ')'; }
|  '{'               { $$ = '{'; }
|  '}'               { $$ = '}'; }
|  '.'               { $$ = '.'; }
|  '&'               { $$ = '&'; }
|  '*'               { $$ = '*'; }
|  '+'               { $$ = '+'; }
|  '-'               { $$ = '-'; }
|  '~'               { $$ = '~'; }
|  '!'               { $$ = '!'; }
|  '/'               { $$ = '/'; }
|  '%'               { $$ = '%'; }
|  LEFT_SHIFT        { $$ = LEFT_SHIFT; }
|  RIGHT_SHIFT       { $$ = RIGHT_SHIFT; }
|  '<'               { $$ = '<'; }
|  '>'               { $$ = '>'; }
|  LESS_OR_EQUAL     { $$ = LESS_OR_EQUAL; }
|  GREATER_OR_EQUAL  { $$ = GREATER_OR_EQUAL; }
|  EQUAL             { $$ = EQUAL; }
|  NOT_EQUAL         { $$ = NOT_EQUAL; }
|  '^'               { $$ = '^'; }
|  '|'               { $$ = '|'; }
|  AND               { $$ = AND; }
|  OR                { $$ = OR; }
|  ';'               { $$ = ';'; }
|  ','               { $$ = ','; }
|  '='               { $$ = '='; }
|  PASTE             { $$ = PASTE; }
|  PLUS_PLUS         { $$ = PLUS_PLUS; }
|  MINUS_MINUS       { $$ = MINUS_MINUS; }
;

%%

string_list_t *
_string_list_create(glcpp_parser_t *parser)
{
   string_list_t *list;

   list = linear_alloc_child(parser->linalloc, sizeof(string_list_t));
   list->head = NULL;
   list->tail = NULL;

   return list;
}

void
_string_list_append_item(glcpp_parser_t *parser, string_list_t *list,
                         const char *str)
{
   string_node_t *node;

   node = linear_alloc_child(parser->linalloc, sizeof(string_node_t));
   node->str = linear_strdup(parser->linalloc, str);

   node->next = NULL;

   if (list->head == NULL) {
      list->head = node;
   } else {
      list->tail->next = node;
   }

   list->tail = node;
}

int
_string_list_contains(string_list_t *list, const char *member, int *index)
{
   string_node_t *node;
   int i;

   if (list == NULL)
      return 0;

   for (i = 0, node = list->head; node; i++, node = node->next) {
      if (strcmp (node->str, member) == 0) {
         if (index)
            *index = i;
         return 1;
      }
   }

   return 0;
}

/* Return duplicate string in list (if any), NULL otherwise. */
const char *
_string_list_has_duplicate(string_list_t *list)
{
   string_node_t *node, *dup;

   if (list == NULL)
      return NULL;

   for (node = list->head; node; node = node->next) {
      for (dup = node->next; dup; dup = dup->next) {
         if (strcmp (node->str, dup->str) == 0)
            return node->str;
      }
   }

   return NULL;
}

int
_string_list_length(string_list_t *list)
{
   int length = 0;
   string_node_t *node;

   if (list == NULL)
      return 0;

   for (node = list->head; node; node = node->next)
      length++;

   return length;
}

int
_string_list_equal(string_list_t *a, string_list_t *b)
{
   string_node_t *node_a, *node_b;

   if (a == NULL && b == NULL)
      return 1;

   if (a == NULL || b == NULL)
      return 0;

   for (node_a = a->head, node_b = b->head;
        node_a && node_b;
        node_a = node_a->next, node_b = node_b->next)
   {
      if (strcmp (node_a->str, node_b->str))
         return 0;
   }

   /* Catch the case of lists being different lengths, (which
    * would cause the loop above to terminate after the shorter
    * list). */
   return node_a == node_b;
}

argument_list_t *
_argument_list_create(glcpp_parser_t *parser)
{
   argument_list_t *list;

   list = linear_alloc_child(parser->linalloc, sizeof(argument_list_t));
   list->head = NULL;
   list->tail = NULL;

   return list;
}

void
_argument_list_append(glcpp_parser_t *parser,
                      argument_list_t *list, token_list_t *argument)
{
   argument_node_t *node;

   node = linear_alloc_child(parser->linalloc, sizeof(argument_node_t));
   node->argument = argument;

   node->next = NULL;

   if (list->head == NULL) {
      list->head = node;
   } else {
      list->tail->next = node;
   }

   list->tail = node;
}

int
_argument_list_length(argument_list_t *list)
{
   int length = 0;
   argument_node_t *node;

   if (list == NULL)
      return 0;

   for (node = list->head; node; node = node->next)
      length++;

   return length;
}

token_list_t *
_argument_list_member_at(argument_list_t *list, int index)
{
   argument_node_t *node;
   int i;

   if (list == NULL)
      return NULL;

   node = list->head;
   for (i = 0; i < index; i++) {
      node = node->next;
      if (node == NULL)
         break;
   }

   if (node)
      return node->argument;

   return NULL;
}

token_t *
_token_create_str(glcpp_parser_t *parser, int type, char *str)
{
   token_t *token;

   token = linear_alloc_child(parser->linalloc, sizeof(token_t));
   token->type = type;
   token->value.str = str;
   token->expanding = false;

   return token;
}

token_t *
_token_create_ival(glcpp_parser_t *parser, int type, int ival)
{
   token_t *token;

   token = linear_alloc_child(parser->linalloc, sizeof(token_t));
   token->type = type;
   token->value.ival = ival;
   token->expanding = false;

   return token;
}

token_list_t *
_token_list_create(glcpp_parser_t *parser)
{
   token_list_t *list;

   list = linear_alloc_child(parser->linalloc, sizeof(token_list_t));
   list->head = NULL;
   list->tail = NULL;
   list->non_space_tail = NULL;

   return list;
}

void
_token_list_prepend(glcpp_parser_t *parser, token_list_t *list, token_t *token)
{
   token_node_t *node;

   node = linear_alloc_child(parser->linalloc, sizeof(token_node_t));
   node->token = token;
   node->next = list->head;

   list->head = node;
}

void
_token_list_append(glcpp_parser_t *parser, token_list_t *list, token_t *token)
{
   token_node_t *node;

   node = linear_alloc_child(parser->linalloc, sizeof(token_node_t));
   node->token = token;
   node->next = NULL;

   if (list->head == NULL) {
      list->head = node;
   } else {
      list->tail->next = node;
   }

   list->tail = node;
   if (token->type != SPACE)
      list->non_space_tail = node;
}

void
_token_list_append_list(token_list_t *list, token_list_t *tail)
{
   if (tail == NULL || tail->head == NULL)
      return;

   if (list->head == NULL) {
      list->head = tail->head;
   } else {
      list->tail->next = tail->head;
   }

   list->tail = tail->tail;
   list->non_space_tail = tail->non_space_tail;
}

static token_list_t *
_token_list_copy(glcpp_parser_t *parser, token_list_t *other)
{
   token_list_t *copy;
   token_node_t *node;

   if (other == NULL)
      return NULL;

   copy = _token_list_create (parser);
   for (node = other->head; node; node = node->next) {
      token_t *new_token = linear_alloc_child(parser->linalloc, sizeof(token_t));
      *new_token = *node->token;
      _token_list_append (parser, copy, new_token);
   }

   return copy;
}

static void
_token_list_trim_trailing_space(token_list_t *list)
{
   if (list->non_space_tail) {
      list->non_space_tail->next = NULL;
      list->tail = list->non_space_tail;
   }
}

static int
_token_list_is_empty_ignoring_space(token_list_t *l)
{
   token_node_t *n;

   if (l == NULL)
      return 1;

   n = l->head;
   while (n != NULL && n->token->type == SPACE)
      n = n->next;

   return n == NULL;
}

int
_token_list_equal_ignoring_space(token_list_t *a, token_list_t *b)
{
   token_node_t *node_a, *node_b;

   if (a == NULL || b == NULL) {
      int a_empty = _token_list_is_empty_ignoring_space(a);
      int b_empty = _token_list_is_empty_ignoring_space(b);
      return a_empty == b_empty;
   }

   node_a = a->head;
   node_b = b->head;

   while (1)
   {
      if (node_a == NULL && node_b == NULL)
         break;

      /* Ignore trailing whitespace */
      if (node_a == NULL && node_b->token->type == SPACE) {
         while (node_b && node_b->token->type == SPACE)
            node_b = node_b->next;
      }

      if (node_a == NULL && node_b == NULL)
         break;

      if (node_b == NULL && node_a->token->type == SPACE) {
         while (node_a && node_a->token->type == SPACE)
            node_a = node_a->next;
      }

      if (node_a == NULL && node_b == NULL)
         break;

      if (node_a == NULL || node_b == NULL)
         return 0;
      /* Make sure whitespace appears in the same places in both.
       * It need not be exactly the same amount of whitespace,
       * though.
       */
      if (node_a->token->type == SPACE && node_b->token->type == SPACE) {
         while (node_a && node_a->token->type == SPACE)
            node_a = node_a->next;
         while (node_b && node_b->token->type == SPACE)
            node_b = node_b->next;
         continue;
      }

      if (node_a->token->type != node_b->token->type)
         return 0;

      switch (node_a->token->type) {
      case INTEGER:
         if (node_a->token->value.ival !=  node_b->token->value.ival) {
            return 0;
         }
         break;
      case IDENTIFIER:
      case INTEGER_STRING:
      case OTHER:
         if (strcmp(node_a->token->value.str, node_b->token->value.str)) {
            return 0;
         }
         break;
      }

      node_a = node_a->next;
      node_b = node_b->next;
   }

   return 1;
}

static void
_token_print(struct _mesa_string_buffer *out, token_t *token)
{
   if (token->type < 256) {
      _mesa_string_buffer_append_char(out, token->type);
      return;
   }

   switch (token->type) {
   case INTEGER:
      _mesa_string_buffer_printf(out, "%" PRIiMAX, token->value.ival);
      break;
   case IDENTIFIER:
   case INTEGER_STRING:
   case PATH:
   case OTHER:
      _mesa_string_buffer_append(out, token->value.str);
      break;
   case SPACE:
      _mesa_string_buffer_append_char(out, ' ');
      break;
   case LEFT_SHIFT:
      _mesa_string_buffer_append(out, "<<");
      break;
   case RIGHT_SHIFT:
      _mesa_string_buffer_append(out, ">>");
      break;
   case LESS_OR_EQUAL:
      _mesa_string_buffer_append(out, "<=");
      break;
   case GREATER_OR_EQUAL:
      _mesa_string_buffer_append(out, ">=");
      break;
   case EQUAL:
      _mesa_string_buffer_append(out, "==");
      break;
   case NOT_EQUAL:
      _mesa_string_buffer_append(out, "!=");
      break;
   case AND:
      _mesa_string_buffer_append(out, "&&");
      break;
   case OR:
      _mesa_string_buffer_append(out, "||");
      break;
   case PASTE:
      _mesa_string_buffer_append(out, "##");
      break;
   case PLUS_PLUS:
      _mesa_string_buffer_append(out, "++");
      break;
   case MINUS_MINUS:
      _mesa_string_buffer_append(out, "--");
      break;
   case DEFINED:
      _mesa_string_buffer_append(out, "defined");
      break;
   case PLACEHOLDER:
      /* Nothing to print. */
      break;
   default:
      assert(!"Error: Don't know how to print token.");

      break;
   }
}

/* Return a new token formed by pasting 'token' and 'other'. Note that this
 * function may return 'token' or 'other' directly rather than allocating
 * anything new.
 *
 * Caution: Only very cursory error-checking is performed to see if
 * the final result is a valid single token. */
static token_t *
_token_paste(glcpp_parser_t *parser, token_t *token, token_t *other)
{
   token_t *combined = NULL;

   /* Pasting a placeholder onto anything makes no change. */
   if (other->type == PLACEHOLDER)
      return token;

   /* When 'token' is a placeholder, just return 'other'. */
   if (token->type == PLACEHOLDER)
      return other;

   /* A very few single-character punctuators can be combined
    * with another to form a multi-character punctuator. */
   switch (token->type) {
   case '<':
      if (other->type == '<')
         combined = _token_create_ival (parser, LEFT_SHIFT, LEFT_SHIFT);
      else if (other->type == '=')
         combined = _token_create_ival (parser, LESS_OR_EQUAL, LESS_OR_EQUAL);
      break;
   case '>':
      if (other->type == '>')
         combined = _token_create_ival (parser, RIGHT_SHIFT, RIGHT_SHIFT);
      else if (other->type == '=')
         combined = _token_create_ival (parser, GREATER_OR_EQUAL, GREATER_OR_EQUAL);
      break;
   case '=':
      if (other->type == '=')
         combined = _token_create_ival (parser, EQUAL, EQUAL);
      break;
   case '!':
      if (other->type == '=')
         combined = _token_create_ival (parser, NOT_EQUAL, NOT_EQUAL);
      break;
   case '&':
      if (other->type == '&')
         combined = _token_create_ival (parser, AND, AND);
      break;
   case '|':
      if (other->type == '|')
         combined = _token_create_ival (parser, OR, OR);
      break;
   }

   if (combined != NULL) {
      /* Inherit the location from the first token */
      combined->location = token->location;
      return combined;
   }

   /* Two string-valued (or integer) tokens can usually just be
    * mashed together. (We also handle a string followed by an
    * integer here as well.)
    *
    * There are some exceptions here. Notably, if the first token
    * is an integer (or a string representing an integer), then
    * the second token must also be an integer or must be a
    * string representing an integer that begins with a digit.
    */
   if ((token->type == IDENTIFIER || token->type == OTHER || token->type == INTEGER_STRING || token->type == INTEGER) &&
       (other->type == IDENTIFIER || other->type == OTHER || other->type == INTEGER_STRING || other->type == INTEGER))
   {
      char *str;
      int combined_type;

      /* Check that pasting onto an integer doesn't create a
       * non-integer, (that is, only digits can be
       * pasted. */
      if (token->type == INTEGER_STRING || token->type == INTEGER) {
         switch (other->type) {
         case INTEGER_STRING:
            if (other->value.str[0] < '0' || other->value.str[0] > '9')
               goto FAIL;
            break;
         case INTEGER:
            if (other->value.ival < 0)
               goto FAIL;
            break;
         default:
            goto FAIL;
         }
      }

      if (token->type == INTEGER)
         str = linear_asprintf(parser->linalloc, "%" PRIiMAX, token->value.ival);
      else
         str = linear_strdup(parser->linalloc, token->value.str);

      if (other->type == INTEGER)
         linear_asprintf_append(parser->linalloc, &str, "%" PRIiMAX, other->value.ival);
      else
         linear_strcat(parser->linalloc, &str, other->value.str);

      /* New token is same type as original token, unless we
       * started with an integer, in which case we will be
       * creating an integer-string. */
      combined_type = token->type;
      if (combined_type == INTEGER)
         combined_type = INTEGER_STRING;

      combined = _token_create_str (parser, combined_type, str);
      combined->location = token->location;
      return combined;
   }

    FAIL:
   glcpp_error (&token->location, parser, "");
   _mesa_string_buffer_append(parser->info_log, "Pasting \"");
   _token_print(parser->info_log, token);
   _mesa_string_buffer_append(parser->info_log, "\" and \"");
   _token_print(parser->info_log, other);
   _mesa_string_buffer_append(parser->info_log, "\" does not give a valid preprocessing token.\n");

   return token;
}

static void
_token_list_print(glcpp_parser_t *parser, token_list_t *list)
{
   token_node_t *node;

   if (list == NULL)
      return;

   for (node = list->head; node; node = node->next)
      _token_print(parser->output, node->token);
}

void
yyerror(YYLTYPE *locp, glcpp_parser_t *parser, const char *error)
{
   glcpp_error(locp, parser, "%s", error);
}

static void
add_builtin_define(glcpp_parser_t *parser, const char *name, int value)
{
   token_t *tok;
   token_list_t *list;

   tok = _token_create_ival (parser, INTEGER, value);

   list = _token_list_create(parser);
   _token_list_append(parser, list, tok);
   _define_object_macro(parser, NULL, name, list);
}

/* Initial output buffer size, 4096 minus ralloc() overhead. It was selected
 * to minimize total amount of allocated memory during shader-db run.
 */
#define INITIAL_PP_OUTPUT_BUF_SIZE 4048

glcpp_parser_t *
glcpp_parser_create(struct gl_context *gl_ctx,
                    glcpp_extension_iterator extensions, void *state)
{
   glcpp_parser_t *parser;

   parser = ralloc (NULL, glcpp_parser_t);

   glcpp_lex_init_extra (parser, &parser->scanner);
   parser->defines = _mesa_hash_table_create(NULL, _mesa_hash_string,
                                             _mesa_key_string_equal);
   parser->linalloc = linear_context(parser);
   parser->active = NULL;
   parser->lexing_directive = 0;
   parser->lexing_version_directive = 0;
   parser->space_tokens = 1;
   parser->last_token_was_newline = 0;
   parser->last_token_was_space = 0;
   parser->first_non_space_token_this_line = 1;
   parser->newline_as_space = 0;
   parser->in_control_line = 0;
   parser->paren_count = 0;
   parser->commented_newlines = 0;

   parser->skip_stack = NULL;
   parser->skipping = 0;

   parser->lex_from_list = NULL;
   parser->lex_from_node = NULL;

   parser->output = _mesa_string_buffer_create(parser,
                                               INITIAL_PP_OUTPUT_BUF_SIZE);
   parser->info_log = _mesa_string_buffer_create(parser,
                                                 INITIAL_PP_OUTPUT_BUF_SIZE);
   parser->error = 0;

   parser->gl_ctx = gl_ctx;
   parser->extensions = extensions;
   parser->extension_list = &gl_ctx->Extensions;
   parser->state = state;
   parser->api = gl_ctx->API;
   parser->version = 0;
   parser->version_set = false;

   parser->has_new_line_number = 0;
   parser->new_line_number = 1;
   parser->has_new_source_number = 0;
   parser->new_source_number = 0;

   parser->is_gles = false;

   return parser;
}

void
glcpp_parser_destroy(glcpp_parser_t *parser)
{
   glcpp_lex_destroy (parser->scanner);
   _mesa_hash_table_destroy(parser->defines, NULL);
   ralloc_free (parser);
}

typedef enum function_status
{
   FUNCTION_STATUS_SUCCESS,
   FUNCTION_NOT_A_FUNCTION,
   FUNCTION_UNBALANCED_PARENTHESES
} function_status_t;

/* Find a set of function-like macro arguments by looking for a
 * balanced set of parentheses.
 *
 * When called, 'node' should be the opening-parenthesis token, (or
 * perhaps preceeding SPACE tokens). Upon successful return *last will
 * be the last consumed node, (corresponding to the closing right
 * parenthesis).
 *
 * Return values:
 *
 *   FUNCTION_STATUS_SUCCESS:
 *
 *      Successfully parsed a set of function arguments.
 *
 *   FUNCTION_NOT_A_FUNCTION:
 *
 *      Macro name not followed by a '('. This is not an error, but
 *      simply that the macro name should be treated as a non-macro.
 *
 *   FUNCTION_UNBALANCED_PARENTHESES
 *
 *      Macro name is not followed by a balanced set of parentheses.
 */
static function_status_t
_arguments_parse(glcpp_parser_t *parser,
                 argument_list_t *arguments, token_node_t *node,
                 token_node_t **last)
{
   token_list_t *argument;
   int paren_count;

   node = node->next;

   /* Ignore whitespace before first parenthesis. */
   while (node && node->token->type == SPACE)
      node = node->next;

   if (node == NULL || node->token->type != '(')
      return FUNCTION_NOT_A_FUNCTION;

   node = node->next;

   argument = _token_list_create (parser);
   _argument_list_append (parser, arguments, argument);

   for (paren_count = 1; node; node = node->next) {
      if (node->token->type == '(') {
         paren_count++;
      } else if (node->token->type == ')') {
         paren_count--;
         if (paren_count == 0)
            break;
      }

      if (node->token->type == ',' && paren_count == 1) {
         _token_list_trim_trailing_space (argument);
         argument = _token_list_create (parser);
         _argument_list_append (parser, arguments, argument);
      } else {
         if (argument->head == NULL) {
            /* Don't treat initial whitespace as part of the argument. */
            if (node->token->type == SPACE)
               continue;
         }
         _token_list_append(parser, argument, node->token);
      }
   }

   if (paren_count)
      return FUNCTION_UNBALANCED_PARENTHESES;

   *last = node;

   return FUNCTION_STATUS_SUCCESS;
}

static token_list_t *
_token_list_create_with_one_ival(glcpp_parser_t *parser, int type, int ival)
{
   token_list_t *list;
   token_t *node;

   list = _token_list_create(parser);
   node = _token_create_ival(parser, type, ival);
   _token_list_append(parser, list, node);

   return list;
}

static token_list_t *
_token_list_create_with_one_space(glcpp_parser_t *parser)
{
   return _token_list_create_with_one_ival(parser, SPACE, SPACE);
}

static token_list_t *
_token_list_create_with_one_integer(glcpp_parser_t *parser, int ival)
{
   return _token_list_create_with_one_ival(parser, INTEGER, ival);
}

/* Evaluate a DEFINED token node (based on subsequent tokens in the list).
 *
 * Note: This function must only be called when "node" is a DEFINED token,
 * (and will abort with an assertion failure otherwise).
 *
 * If "node" is followed, (ignoring any SPACE tokens), by an IDENTIFIER token
 * (optionally preceded and followed by '(' and ')' tokens) then the following
 * occurs:
 *
 *   If the identifier is a defined macro, this function returns 1.
 *
 *   If the identifier is not a defined macro, this function returns 0.
 *
 *   In either case, *last will be updated to the last node in the list
 *   consumed by the evaluation, (either the token of the identifier or the
 *   token of the closing parenthesis).
 *
 * In all other cases, (such as "node is the final node of the list", or
 * "missing closing parenthesis", etc.), this function generates a
 * preprocessor error, returns -1 and *last will not be set.
 */
static int
_glcpp_parser_evaluate_defined(glcpp_parser_t *parser, token_node_t *node,
                               token_node_t **last)
{
   token_node_t *argument, *defined = node;

   assert(node->token->type == DEFINED);

   node = node->next;

   /* Ignore whitespace after DEFINED token. */
   while (node && node->token->type == SPACE)
      node = node->next;

   if (node == NULL)
      goto FAIL;

   if (node->token->type == IDENTIFIER || node->token->type == OTHER) {
      argument = node;
   } else if (node->token->type == '(') {
      node = node->next;

      /* Ignore whitespace after '(' token. */
      while (node && node->token->type == SPACE)
         node = node->next;

      if (node == NULL || (node->token->type != IDENTIFIER &&
                           node->token->type != OTHER)) {
         goto FAIL;
      }

      argument = node;

      node = node->next;

      /* Ignore whitespace after identifier, before ')' token. */
      while (node && node->token->type == SPACE)
         node = node->next;

      if (node == NULL || node->token->type != ')')
         goto FAIL;
   } else {
      goto FAIL;
   }

   *last = node;

   return _mesa_hash_table_search(parser->defines,
                                  argument->token->value.str) ? 1 : 0;

FAIL:
   glcpp_error (&defined->token->location, parser,
                "\"defined\" not followed by an identifier");
   return -1;
}

/* Evaluate all DEFINED nodes in a given list, modifying the list in place.
 */
static void
_glcpp_parser_evaluate_defined_in_list(glcpp_parser_t *parser,
                                       token_list_t *list)
{
   token_node_t *node, *node_prev, *replacement, *last = NULL;
   int value;

   if (list == NULL)
      return;

   node_prev = NULL;
   node = list->head;

   while (node) {

      if (node->token->type != DEFINED)
         goto NEXT;

      value = _glcpp_parser_evaluate_defined (parser, node, &last);
      if (value == -1)
         goto NEXT;

      replacement = linear_alloc_child(parser->linalloc, sizeof(token_node_t));
      replacement->token = _token_create_ival (parser, INTEGER, value);

      /* Splice replacement node into list, replacing from "node"
       * through "last". */
      if (node_prev)
         node_prev->next = replacement;
      else
         list->head = replacement;
      replacement->next = last->next;
      if (last == list->tail)
         list->tail = replacement;

      node = replacement;

   NEXT:
      node_prev = node;
      node = node->next;
   }
}

/* Perform macro expansion on 'list', placing the resulting tokens
 * into a new list which is initialized with a first token of type
 * 'head_token_type'. Then begin lexing from the resulting list,
 * (return to the current lexing source when this list is exhausted).
 *
 * See the documentation of _glcpp_parser_expand_token_list for a description
 * of the "mode" parameter.
 */
static void
_glcpp_parser_expand_and_lex_from(glcpp_parser_t *parser, int head_token_type,
                                  token_list_t *list, expansion_mode_t mode)
{
   token_list_t *expanded;
   token_t *token;

   expanded = _token_list_create (parser);
   token = _token_create_ival (parser, head_token_type, head_token_type);
   _token_list_append (parser, expanded, token);
   _glcpp_parser_expand_token_list (parser, list, mode);
   _token_list_append_list (expanded, list);
   glcpp_parser_lex_from (parser, expanded);
}

static void
_glcpp_parser_apply_pastes(glcpp_parser_t *parser, token_list_t *list)
{
   token_node_t *node;

   node = list->head;
   while (node) {
      token_node_t *next_non_space;

      /* Look ahead for a PASTE token, skipping space. */
      next_non_space = node->next;
      while (next_non_space && next_non_space->token->type == SPACE)
         next_non_space = next_non_space->next;

      if (next_non_space == NULL)
         break;

      if (next_non_space->token->type != PASTE) {
         node = next_non_space;
         continue;
      }

      /* Now find the next non-space token after the PASTE. */
      next_non_space = next_non_space->next;
      while (next_non_space && next_non_space->token->type == SPACE)
         next_non_space = next_non_space->next;

      if (next_non_space == NULL) {
         yyerror(&node->token->location, parser, "'##' cannot appear at either end of a macro expansion\n");
         return;
      }

      node->token = _token_paste(parser, node->token, next_non_space->token);
      node->next = next_non_space->next;
      if (next_non_space == list->tail)
         list->tail = node;
   }

   list->non_space_tail = list->tail;
}

/* This is a helper function that's essentially part of the
 * implementation of _glcpp_parser_expand_node. It shouldn't be called
 * except for by that function.
 *
 * Returns NULL if node is a simple token with no expansion, (that is,
 * although 'node' corresponds to an identifier defined as a
 * function-like macro, it is not followed with a parenthesized
 * argument list).
 *
 * Compute the complete expansion of node (which is a function-like
 * macro) and subsequent nodes which are arguments.
 *
 * Returns the token list that results from the expansion and sets
 * *last to the last node in the list that was consumed by the
 * expansion. Specifically, *last will be set as follows: as the
 * token of the closing right parenthesis.
 *
 * See the documentation of _glcpp_parser_expand_token_list for a description
 * of the "mode" parameter.
 */
static token_list_t *
_glcpp_parser_expand_function(glcpp_parser_t *parser, token_node_t *node,
                              token_node_t **last, expansion_mode_t mode,
                              macro_t *macro)
{
   const char *identifier;
   argument_list_t *arguments;
   function_status_t status;
   token_list_t *substituted;
   int parameter_index;

   assert(macro);
   assert(macro->is_function);

   identifier = node->token->value.str;
   arguments = _argument_list_create(parser);
   status = _arguments_parse(parser, arguments, node, last);

   switch (status) {
   case FUNCTION_STATUS_SUCCESS:
      break;
   case FUNCTION_NOT_A_FUNCTION:
      return NULL;
   case FUNCTION_UNBALANCED_PARENTHESES:
      glcpp_error(&node->token->location, parser, "Macro %s call has unbalanced parentheses\n", identifier);
      return NULL;
   }

   /* Replace a macro defined as empty with a SPACE token. */
   if (macro->replacements == NULL) {
      return _token_list_create_with_one_space(parser);
   }

   if (!((_argument_list_length (arguments) ==
          _string_list_length (macro->parameters)) ||
         (_string_list_length (macro->parameters) == 0 &&
          _argument_list_length (arguments) == 1 &&
          arguments->head->argument->head == NULL))) {
      glcpp_error(&node->token->location, parser,
                  "Error: macro %s invoked with %d arguments (expected %d)\n",
                  identifier, _argument_list_length (arguments),
                  _string_list_length(macro->parameters));
      return NULL;
   }

   /* Perform argument substitution on the replacement list. */
   substituted = _token_list_create(parser);

   for (node = macro->replacements->head; node; node = node->next) {
      if (node->token->type == IDENTIFIER &&
          _string_list_contains(macro->parameters, node->token->value.str,
                                &parameter_index)) {
         token_list_t *argument;
         argument = _argument_list_member_at(arguments, parameter_index);
         /* Before substituting, we expand the argument tokens, or append a
          * placeholder token for an empty argument. */
         if (argument->head) {
            token_list_t *expanded_argument;
            expanded_argument = _token_list_copy(parser, argument);
            _glcpp_parser_expand_token_list(parser, expanded_argument, mode);
            _token_list_append_list(substituted, expanded_argument);
         } else {
            token_t *new_token;

            new_token = _token_create_ival(parser, PLACEHOLDER,
                                           PLACEHOLDER);
            _token_list_append(parser, substituted, new_token);
         }
      } else {
         _token_list_append(parser, substituted, node->token);
      }
   }

   /* After argument substitution, and before further expansion
    * below, implement token pasting. */

   _token_list_trim_trailing_space(substituted);

   _glcpp_parser_apply_pastes(parser, substituted);

   return substituted;
}

/* Compute the complete expansion of node, (and subsequent nodes after
 * 'node' in the case that 'node' is a function-like macro and
 * subsequent nodes are arguments).
 *
 * Returns NULL if node is a simple token with no expansion.
 *
 * Otherwise, returns the token list that results from the expansion
 * and sets *last to the last node in the list that was consumed by
 * the expansion. Specifically, *last will be set as follows:
 *
 *   As 'node' in the case of object-like macro expansion.
 *
 *   As the token of the closing right parenthesis in the case of
 *   function-like macro expansion.
 *
 * See the documentation of _glcpp_parser_expand_token_list for a description
 * of the "mode" parameter.
 */
static token_list_t *
_glcpp_parser_expand_node(glcpp_parser_t *parser, token_node_t *node,
                          token_node_t *node_prev, token_node_t **last,
                          expansion_mode_t mode, int line)
{
   token_t *token = node->token;
   const char *identifier;
   struct hash_entry *entry;
   macro_t *macro;

   /* If token is already being expanded return to avoid an infinite loop */
   if (token->expanding)
      return NULL;

   /* We only expand identifiers */
   if (token->type != IDENTIFIER) {
      return NULL;
   }

   *last = node;
   identifier = token->value.str;

   /* Special handling for __LINE__ and __FILE__, (not through
    * the hash table). */
   if (*identifier == '_') {
      if (strcmp(identifier, "__LINE__") == 0)
         return _token_list_create_with_one_integer(parser, line);

      if (strcmp(identifier, "__FILE__") == 0)
         return _token_list_create_with_one_integer(parser,
                                                    node->token->location.source);
   }

   /* Look up this identifier in the hash table. */
   entry = _mesa_hash_table_search(parser->defines, identifier);
   macro = entry ? entry->data : NULL;

   /* Not a macro, so no expansion needed. */
   if (macro == NULL)
      return NULL;

   /* Finally, don't expand this macro if we're already actively
    * expanding it, (to avoid infinite recursion). */
   if (_parser_active_list_contains (parser, identifier)) {
      /* We change the `expanding` bool to true to prevent any
       * future expansion of this unexpanded token. */
      char *str;
      token_list_t *expansion;
      token_t *final;

      str = linear_strdup(parser->linalloc, token->value.str);
      final = _token_create_str(parser, token->type, str);
      final->expanding = true;
      expansion = _token_list_create(parser);
      _token_list_append(parser, expansion, final);
      return expansion;
   }

   if (! macro->is_function) {
      token_list_t *replacement;

      /* Replace a macro defined as empty with a SPACE token. */
      if (macro->replacements == NULL)
         return _token_list_create_with_one_space(parser);

      replacement = _token_list_copy(parser, macro->replacements);

      /* If needed insert space in front of replacements to isolate them from
       * the code they will be inserted into. For example:
       *
       *    #define VALUE -1.0
       *    int a = -VALUE;
       *
       * Should be evaluated to int a = - -1.0; not int a = --1.0;
       */
      if (node_prev &&
          (node_prev->token->type == '-' || node_prev->token->type == '+') &&
          node_prev->token->type == replacement->head->token->type) {
         token_t *new_token = _token_create_ival(parser, SPACE, SPACE);
         _token_list_prepend(parser, replacement, new_token);
      }

      _glcpp_parser_apply_pastes(parser, replacement);
      return replacement;
   }

   return _glcpp_parser_expand_function(parser, node, last, mode, macro);
}

/* Push a new identifier onto the parser's active list.
 *
 * Here, 'marker' is the token node that appears in the list after the
 * expansion of 'identifier'. That is, when the list iterator begins
 * examining 'marker', then it is time to pop this node from the
 * active stack.
 */
static void
_parser_active_list_push(glcpp_parser_t *parser, const char *identifier,
                         token_node_t *marker)
{
   active_list_t *node;

   node = linear_alloc_child(parser->linalloc, sizeof(active_list_t));
   node->identifier = linear_strdup(parser->linalloc, identifier);
   node->marker = marker;
   node->next = parser->active;

   parser->active = node;
}

static void
_parser_active_list_pop(glcpp_parser_t *parser)
{
   active_list_t *node = parser->active;

   if (node == NULL) {
      parser->active = NULL;
      return;
   }

   node = parser->active->next;
   parser->active = node;
}

static int
_parser_active_list_contains(glcpp_parser_t *parser, const char *identifier)
{
   active_list_t *node;

   if (parser->active == NULL)
      return 0;

   for (node = parser->active; node; node = node->next)
      if (strcmp(node->identifier, identifier) == 0)
         return 1;

   return 0;
}

/* Walk over the token list replacing nodes with their expansion.
 * Whenever nodes are expanded the walking will walk over the new
 * nodes, continuing to expand as necessary. The results are placed in
 * 'list' itself.
 *
 * The "mode" argument controls the handling of any DEFINED tokens that
 * result from expansion as follows:
 *
 *   EXPANSION_MODE_IGNORE_DEFINED: Any resulting DEFINED tokens will be
 *      left in the final list, unevaluated. This is the correct mode
 *      for expanding any list in any context other than a
 *      preprocessor conditional, (#if or #elif).
 *
 *   EXPANSION_MODE_EVALUATE_DEFINED: Any resulting DEFINED tokens will be
 *      evaluated to 0 or 1 tokens depending on whether the following
 *      token is the name of a defined macro. If the DEFINED token is
 *      not followed by an (optionally parenthesized) identifier, then
 *      an error will be generated. This the correct mode for
 *      expanding any list in the context of a preprocessor
 *      conditional, (#if or #elif).
 */
static void
_glcpp_parser_expand_token_list(glcpp_parser_t *parser, token_list_t *list,
                                expansion_mode_t mode)
{
   token_node_t *node_prev;
   token_node_t *node, *last = NULL;
   token_list_t *expansion;
   active_list_t *active_initial = parser->active;
   int line;

   if (list == NULL)
      return;

   _token_list_trim_trailing_space (list);

   line = list->tail->token->location.last_line;

   node_prev = NULL;
   node = list->head;

   if (mode == EXPANSION_MODE_EVALUATE_DEFINED)
      _glcpp_parser_evaluate_defined_in_list (parser, list);

   while (node) {

      while (parser->active && parser->active->marker == node)
         _parser_active_list_pop (parser);

      expansion =
         _glcpp_parser_expand_node(parser, node, node_prev, &last, mode, line);
      if (expansion) {
         token_node_t *n;

         if (mode == EXPANSION_MODE_EVALUATE_DEFINED) {
            _glcpp_parser_evaluate_defined_in_list (parser, expansion);
         }

         for (n = node; n != last->next; n = n->next)
            while (parser->active && parser->active->marker == n) {
               _parser_active_list_pop (parser);
            }

         _parser_active_list_push(parser, node->token->value.str, last->next);

         /* Splice expansion into list, supporting a simple deletion if the
          * expansion is empty.
          */
         if (expansion->head) {
            if (node_prev)
               node_prev->next = expansion->head;
            else
               list->head = expansion->head;
            expansion->tail->next = last->next;
            if (last == list->tail)
               list->tail = expansion->tail;
         } else {
            if (node_prev)
               node_prev->next = last->next;
            else
               list->head = last->next;
            if (last == list->tail)
               list->tail = NULL;
         }
      } else {
         node_prev = node;
      }
      node = node_prev ? node_prev->next : list->head;
   }

   /* Remove any lingering effects of this invocation on the
    * active list. That is, pop until the list looks like it did
    * at the beginning of this function. */
   while (parser->active && parser->active != active_initial)
      _parser_active_list_pop (parser);

   list->non_space_tail = list->tail;
}

void
_glcpp_parser_print_expanded_token_list(glcpp_parser_t *parser,
                                        token_list_t *list)
{
   if (list == NULL)
      return;

   _glcpp_parser_expand_token_list (parser, list, EXPANSION_MODE_IGNORE_DEFINED);

   _token_list_trim_trailing_space (list);

   _token_list_print (parser, list);
}

static void
_check_for_reserved_macro_name(glcpp_parser_t *parser, YYLTYPE *loc,
                               const char *identifier)
{
   /* Section 3.3 (Preprocessor) of the GLSL 1.30 spec (and later) and
    * the GLSL ES spec (all versions) say:
    *
    *     "All macro names containing two consecutive underscores ( __ )
    *     are reserved for future use as predefined macro names. All
    *     macro names prefixed with "GL_" ("GL" followed by a single
    *     underscore) are also reserved."
    *
    * The intention is that names containing __ are reserved for internal
    * use by the implementation, and names prefixed with GL_ are reserved
    * for use by Khronos.  Since every extension adds a name prefixed
    * with GL_ (i.e., the name of the extension), that should be an
    * error.  Names simply containing __ are dangerous to use, but should
    * be allowed.
    *
    * A future version of the GLSL specification will clarify this.
    */
   if (strstr(identifier, "__")) {
      glcpp_warning(loc, parser, "Macro names containing \"__\" are reserved "
                    "for use by the implementation.\n");
   }
   if (strncmp(identifier, "GL_", 3) == 0) {
      glcpp_error (loc, parser, "Macro names starting with \"GL_\" are reserved.\n");
   }
   if (strcmp(identifier, "defined") == 0) {
      glcpp_error (loc, parser, "\"defined\" cannot be used as a macro name");
   }
}

static int
_macro_equal(macro_t *a, macro_t *b)
{
   if (a->is_function != b->is_function)
      return 0;

   if (a->is_function) {
      if (! _string_list_equal (a->parameters, b->parameters))
         return 0;
   }

   return _token_list_equal_ignoring_space(a->replacements, b->replacements);
}

void
_define_object_macro(glcpp_parser_t *parser, YYLTYPE *loc,
                     const char *identifier, token_list_t *replacements)
{
   macro_t *macro, *previous;
   struct hash_entry *entry;

   /* We define pre-defined macros before we've started parsing the actual
    * file. So if there's no location defined yet, that's what were doing and
    * we don't want to generate an error for using the reserved names. */
   if (loc != NULL)
      _check_for_reserved_macro_name(parser, loc, identifier);

   macro = linear_alloc_child(parser->linalloc, sizeof(macro_t));

   macro->is_function = 0;
   macro->parameters = NULL;
   macro->identifier = linear_strdup(parser->linalloc, identifier);
   macro->replacements = replacements;

   entry = _mesa_hash_table_search(parser->defines, identifier);
   previous = entry ? entry->data : NULL;
   if (previous) {
      if (_macro_equal (macro, previous)) {
         return;
      }
      glcpp_error (loc, parser, "Redefinition of macro %s\n",  identifier);
   }

   _mesa_hash_table_insert (parser->defines, identifier, macro);
}

void
_define_function_macro(glcpp_parser_t *parser, YYLTYPE *loc,
                       const char *identifier, string_list_t *parameters,
                       token_list_t *replacements)
{
   macro_t *macro, *previous;
   struct hash_entry *entry;
   const char *dup;

   _check_for_reserved_macro_name(parser, loc, identifier);

        /* Check for any duplicate parameter names. */
   if ((dup = _string_list_has_duplicate (parameters)) != NULL) {
      glcpp_error (loc, parser, "Duplicate macro parameter \"%s\"", dup);
   }

   macro = linear_alloc_child(parser->linalloc, sizeof(macro_t));

   macro->is_function = 1;
   macro->parameters = parameters;
   macro->identifier = linear_strdup(parser->linalloc, identifier);
   macro->replacements = replacements;

   entry = _mesa_hash_table_search(parser->defines, identifier);
   previous = entry ? entry->data : NULL;
   if (previous) {
      if (_macro_equal (macro, previous)) {
         return;
      }
      glcpp_error (loc, parser, "Redefinition of macro %s\n", identifier);
   }

   _mesa_hash_table_insert(parser->defines, identifier, macro);
}

static int
glcpp_parser_lex(YYSTYPE *yylval, YYLTYPE *yylloc, glcpp_parser_t *parser)
{
   token_node_t *node;
   int ret;

   if (parser->lex_from_list == NULL) {
      ret = glcpp_lex(yylval, yylloc, parser->scanner);

      /* XXX: This ugly block of code exists for the sole
       * purpose of converting a NEWLINE token into a SPACE
       * token, but only in the case where we have seen a
       * function-like macro name, but have not yet seen its
       * closing parenthesis.
       *
       * There's perhaps a more compact way to do this with
       * mid-rule actions in the grammar.
       *
       * I'm definitely not pleased with the complexity of
       * this code here.
       */
      if (parser->newline_as_space) {
         if (ret == '(') {
            parser->paren_count++;
         } else if (ret == ')') {
            parser->paren_count--;
            if (parser->paren_count == 0)
               parser->newline_as_space = 0;
         } else if (ret == NEWLINE) {
            ret = SPACE;
         } else if (ret != SPACE) {
            if (parser->paren_count == 0)
               parser->newline_as_space = 0;
         }
      } else if (parser->in_control_line) {
         if (ret == NEWLINE)
            parser->in_control_line = 0;
      }
      else if (ret == DEFINE_TOKEN || ret == UNDEF || ret == IF ||
               ret == IFDEF || ret == IFNDEF || ret == ELIF || ret == ELSE ||
               ret == ENDIF || ret == HASH_TOKEN) {
         parser->in_control_line = 1;
      } else if (ret == IDENTIFIER) {
         struct hash_entry *entry = _mesa_hash_table_search(parser->defines,
                                                            yylval->str);
         macro_t *macro = entry ? entry->data : NULL;
         if (macro && macro->is_function) {
            parser->newline_as_space = 1;
            parser->paren_count = 0;
         }
      }

      return ret;
   }

   node = parser->lex_from_node;

   if (node == NULL) {
      parser->lex_from_list = NULL;
      return NEWLINE;
   }

   *yylval = node->token->value;
   ret = node->token->type;

   parser->lex_from_node = node->next;

   return ret;
}

static void
glcpp_parser_lex_from(glcpp_parser_t *parser, token_list_t *list)
{
   token_node_t *node;

   assert (parser->lex_from_list == NULL);

   /* Copy list, eliminating any space tokens. */
   parser->lex_from_list = _token_list_create (parser);

   for (node = list->head; node; node = node->next) {
      if (node->token->type == SPACE)
         continue;
      _token_list_append (parser,  parser->lex_from_list, node->token);
   }

   parser->lex_from_node = parser->lex_from_list->head;

   /* It's possible the list consisted of nothing but whitespace. */
   if (parser->lex_from_node == NULL) {
      parser->lex_from_list = NULL;
   }
}

static void
_glcpp_parser_skip_stack_push_if(glcpp_parser_t *parser, YYLTYPE *loc,
                                 int condition)
{
   skip_type_t current = SKIP_NO_SKIP;
   skip_node_t *node;

   if (parser->skip_stack)
      current = parser->skip_stack->type;

   node = linear_alloc_child(parser->linalloc, sizeof(skip_node_t));
   node->loc = *loc;

   if (current == SKIP_NO_SKIP) {
      if (condition)
         node->type = SKIP_NO_SKIP;
      else
         node->type = SKIP_TO_ELSE;
   } else {
      node->type = SKIP_TO_ENDIF;
   }

   node->has_else = false;
   node->next = parser->skip_stack;
   parser->skip_stack = node;
}

static void
_glcpp_parser_skip_stack_change_if(glcpp_parser_t *parser, YYLTYPE *loc,
                                   const char *type, int condition)
{
   if (parser->skip_stack == NULL) {
      glcpp_error (loc, parser, "#%s without #if\n", type);
      return;
   }

   if (parser->skip_stack->type == SKIP_TO_ELSE) {
      if (condition)
         parser->skip_stack->type = SKIP_NO_SKIP;
   } else {
      parser->skip_stack->type = SKIP_TO_ENDIF;
   }
}

static void
_glcpp_parser_skip_stack_pop(glcpp_parser_t *parser, YYLTYPE *loc)
{
   skip_node_t *node;

   if (parser->skip_stack == NULL) {
      glcpp_error (loc, parser, "#endif without #if\n");
      return;
   }

   node = parser->skip_stack;
   parser->skip_stack = node->next;
}

static void
_glcpp_parser_handle_version_declaration(glcpp_parser_t *parser, intmax_t version,
                                         const char *identifier,
                                         bool explicitly_set)
{
   if (parser->version_set)
      return;

   parser->version = version;
   parser->version_set = true;

   add_builtin_define (parser, "__VERSION__", version);

   parser->is_gles = (version == 100) ||
                     (identifier && (strcmp(identifier, "es") == 0));
   bool is_compat = version >= 150 && identifier &&
                    strcmp(identifier, "compatibility") == 0;

   /* Add pre-defined macros. */
   if (parser->is_gles)
      add_builtin_define(parser, "GL_ES", 1);
   else if (is_compat)
      add_builtin_define(parser, "GL_compatibility_profile", 1);
   else if (version >= 150)
      add_builtin_define(parser, "GL_core_profile", 1);

   /* Currently, all ES2/ES3 implementations support highp in the
    * fragment shader, so we always define this macro in ES2/ES3.
    * If we ever get a driver that doesn't support highp, we'll
    * need to add a flag to the gl_context and check that here.
    */
   if (version >= 130 || parser->is_gles)
      add_builtin_define (parser, "GL_FRAGMENT_PRECISION_HIGH", 1);

   /* Add all the extension macros available in this context */
   if (parser->extensions)
      parser->extensions(parser->state, add_builtin_define, parser,
                         version, parser->is_gles);

   if (parser->extension_list) {
      /* If MESA_shader_integer_functions is supported, then the building
       * blocks required for the 64x64 => 64 multiply exist.  Add defines for
       * those functions so that they can be tested.
       */
      if (parser->extension_list->MESA_shader_integer_functions) {
         add_builtin_define(parser, "__have_builtin_builtin_udiv64", 1);
         add_builtin_define(parser, "__have_builtin_builtin_umod64", 1);
         add_builtin_define(parser, "__have_builtin_builtin_idiv64", 1);
         add_builtin_define(parser, "__have_builtin_builtin_imod64", 1);
      }
   }

   if (explicitly_set) {
      _mesa_string_buffer_printf(parser->output,
                                 "#version %" PRIiMAX "%s%s", version,
                                 identifier ? " " : "",
                                 identifier ? identifier : "");
   }
}

/* GLSL version if no version is explicitly specified. */
#define IMPLICIT_GLSL_VERSION 110

/* GLSL ES version if no version is explicitly specified. */
#define IMPLICIT_GLSL_ES_VERSION 100

void
glcpp_parser_resolve_implicit_version(glcpp_parser_t *parser)
{
   int language_version = parser->api == API_OPENGLES2 ?
                          IMPLICIT_GLSL_ES_VERSION : IMPLICIT_GLSL_VERSION;

   _glcpp_parser_handle_version_declaration(parser, language_version,
                                            NULL, false);
}

static void
glcpp_parser_copy_defines(const void *key, void *data, void *closure)
{
   struct define_include *di = (struct define_include *) closure;
   macro_t *macro = (macro_t *) data;

   /* If we hit an error on a previous pass, just return */
   if (di->parser->error)
      return;

   const char *identifier =  macro->identifier;
   struct hash_entry *entry = _mesa_hash_table_search(di->parser->defines,
                                                      identifier);

   macro_t *previous = entry ? entry->data : NULL;
   if (previous) {
      if (_macro_equal(macro, previous)) {
         return;
      }
      glcpp_error(di->loc, di->parser, "Redefinition of macro %s\n",
                  identifier);
   }

   _mesa_hash_table_insert(di->parser->defines, identifier, macro);
}