src/glsl/glsl_symbol_table.cpp

   1 /* -*- c++ -*- */
   2 /*
   3  * Copyright © 2010 Intel Corporation
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   9  * and/or sell copies of the Software, and to permit persons to whom the
  10  * Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice (including the next
  13  * paragraph) shall be included in all copies or substantial portions of the
  14  * Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  22  * DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 #include "glsl_symbol_table.h"
  26
  27 class symbol_table_entry {
  28 public:
  29    /* Callers of this talloc-based new need not call delete. It's
  30     * easier to just talloc_free 'ctx' (or any of its ancestors). */
  31    static void* operator new(size_t size, void *ctx)
  32    {
  33       void *entry = talloc_size(ctx, size);
  34       assert(entry != NULL);
  35       return entry;
  36    }
  37
  38    /* If the user *does* call delete, that's OK, we will just
  39     * talloc_free in that case. Here, C++ will have already called the
  40     * destructor so tell talloc not to do that again. */
  41    static void operator delete(void *table)
  42    {
  43       talloc_set_destructor(table, NULL);
  44       talloc_free(table);
  45    }
  46
  47    symbol_table_entry(ir_variable *v)                     : v(v), f(0), t(0) {}
  48    symbol_table_entry(ir_function *f)                     : v(0), f(f), t(0) {}
  49    symbol_table_entry(const glsl_type *t, ir_function *f) : v(0), f(f), t(t) {}
  50
  51    ir_variable *v;
  52    ir_function *f;
  53    const glsl_type *t;
  54 };
  55
  56 glsl_symbol_table::glsl_symbol_table()
  57 {
  58    this->language_version = 120;
  59    this->table = _mesa_symbol_table_ctor();
  60    this->mem_ctx = talloc_init("symbol table entries");
  61 }
  62
  63 glsl_symbol_table::~glsl_symbol_table()
  64 {
  65    _mesa_symbol_table_dtor(table);
  66    talloc_free(mem_ctx);
  67 }
  68
  69 void glsl_symbol_table::push_scope()
  70 {
  71    _mesa_symbol_table_push_scope(table);
  72 }
  73
  74 void glsl_symbol_table::pop_scope()
  75 {
  76    _mesa_symbol_table_pop_scope(table);
  77 }
  78
  79 bool glsl_symbol_table::name_declared_this_scope(const char *name)
  80 {
  81    return _mesa_symbol_table_symbol_scope(table, -1, name) == 0;
  82 }
  83
  84 bool glsl_symbol_table::add_variable(const char *name, ir_variable *v)
  85 {
  86    if (this->language_version == 110) {
  87       /* In 1.10, functions and variables have separate namespaces. */
  88       symbol_table_entry *existing = get_entry(name);
  89       if (name_declared_this_scope(name)) {
  90          /* If there's already an existing function (not a constructor!) in
  91           * the current scope, just update the existing entry to include 'v'.
  92           */
  93          if (existing->v == NULL && existing->t == NULL) {
  94             existing->v = v;
  95             return true;
  96          }
  97       } else {
  98          /* If not declared at this scope, add a new entry.  But if an existing
  99           * entry includes a function, propagate that to this block - otherwise
 100           * the new variable declaration would shadow the function.
 101           */
 102          symbol_table_entry *entry = new(mem_ctx) symbol_table_entry(v);
 103          if (existing != NULL)
 104             entry->f = existing->f;
 105          int added = _mesa_symbol_table_add_symbol(table, -1, name, entry);
 106          assert(added == 0);
 107          (void)added;
 108          return true;
 109       }
 110       return false;
 111    }
 112
 113    /* 1.20+ rules: */
 114    symbol_table_entry *entry = new(mem_ctx) symbol_table_entry(v);
 115    return _mesa_symbol_table_add_symbol(table, -1, name, entry) == 0;
 116 }
 117
 118 bool glsl_symbol_table::add_type(const char *name, const glsl_type *t,
 119                                  ir_function *constructor)
 120 {
 121    symbol_table_entry *entry = new(mem_ctx) symbol_table_entry(t, constructor);
 122    return _mesa_symbol_table_add_symbol(table, -1, name, entry) == 0;
 123 }
 124
 125 bool glsl_symbol_table::add_function(const char *name, ir_function *f)
 126 {
 127    if (this->language_version == 110 && name_declared_this_scope(name)) {
 128       /* In 1.10, functions and variables have separate namespaces. */
 129       symbol_table_entry *existing = get_entry(name);
 130       if (existing->f == NULL) {
 131          existing->f = f;
 132          return true;
 133       }
 134    }
 135    symbol_table_entry *entry = new(mem_ctx) symbol_table_entry(f);
 136    return _mesa_symbol_table_add_symbol(table, -1, name, entry) == 0;
 137 }
 138
 139 ir_variable *glsl_symbol_table::get_variable(const char *name)
 140 {
 141    symbol_table_entry *entry = get_entry(name);
 142    return entry != NULL ? entry->v : NULL;
 143 }
 144
 145 const glsl_type *glsl_symbol_table::get_type(const char *name)
 146 {
 147    symbol_table_entry *entry = get_entry(name);
 148    return entry != NULL ? entry->t : NULL;
 149 }
 150
 151 ir_function *glsl_symbol_table::get_function(const char *name,
 152                                              bool return_constructors)
 153 {
 154    symbol_table_entry *entry = get_entry(name);
 155    // If there's a type, the function is a constructor; caller may not want it.
 156    if (entry != NULL && (return_constructors || entry->t == NULL))
 157       return entry->f;
 158
 159    return NULL;
 160 }
 161
 162 symbol_table_entry *glsl_symbol_table::get_entry(const char *name)
 163 {
 164    return (symbol_table_entry *)
 165       _mesa_symbol_table_find_symbol(table, -1, name);
 166 }