glsl: Support if preprocessor directive and friends.

1 files changed, 276 insertions, 0 deletions

diff --git a/src/glsl/pp/sl_pp_if.c b/src/glsl/pp/sl_pp_if.c
new file mode 100644
index 0000000000..e331acc4cd
--- /dev/null
+++ b/src/glsl/pp/sl_pp_if.c
@@ -0,0 +1,276 @@
+/**************************************************************************
+ * 
+ * Copyright 2009 VMware, Inc.
+ * All Rights Reserved.
+ * 
+ * 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, sub license, 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 NON-INFRINGEMENT.
+ * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS 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 <stdlib.h>
+#include "sl_pp_expression.h"
+#include "sl_pp_process.h"
+
+
+static int
+_evaluate_if_stack(struct sl_pp_context *context)
+{
+   unsigned int i;
+
+   for (i = context->if_ptr; i < SL_PP_MAX_IF_NESTING; i++) {
+      if (!(context->if_stack[i] & 1)) {
+         return 0;
+      }
+   }
+   return 1;
+}
+
+static int
+_parse_if(struct sl_pp_context *context,
+          const struct sl_pp_token_info *input,
+          unsigned int first,
+          unsigned int last)
+{
+   unsigned int i;
+   struct sl_pp_process_state state;
+   struct sl_pp_token_info eof;
+   int result;
+
+   if (!context->if_ptr) {
+      /* #if nesting too deep. */
+      return -1;
+   }
+
+   memset(&state, 0, sizeof(state));
+   for (i = first; i < last;) {
+      switch (input[i].token) {
+      case SL_PP_WHITESPACE:
+         i++;
+         break;
+
+      case SL_PP_IDENTIFIER:
+         if (sl_pp_macro_expand(context, input, &i, NULL, &state, 0)) {
+            free(state.out);
+            return -1;
+         }
+         break;
+
+      default:
+         if (sl_pp_process_out(&state, &input[i])) {
+            free(state.out);
+            return -1;
+         }
+         i++;
+      }
+   }
+
+   eof.token = SL_PP_EOF;
+   if (sl_pp_process_out(&state, &eof)) {
+      free(state.out);
+      return -1;
+   }
+
+   if (sl_pp_execute_expression(context, state.out, &result)) {
+      free(state.out);
+      return -1;
+   }
+
+   free(state.out);
+
+   context->if_ptr--;
+   context->if_stack[context->if_ptr] = result ? 1 : 0;
+   context->if_value = _evaluate_if_stack(context);
+
+   return 0;
+}
+
+static int
+_parse_else(struct sl_pp_context *context)
+{
+   if (context->if_ptr == SL_PP_MAX_IF_NESTING) {
+      /* No matching #if. */
+      return -1;
+   }
+
+   /* Bit b1 indicates we already went through #else. */
+   if (context->if_stack[context->if_ptr] & 2) {
+      /* No matching #if. */
+      return -1;
+   }
+
+   /* Invert current condition value and mark that we are in the #else block. */
+   context->if_stack[context->if_ptr] = (1 - (context->if_stack[context->if_ptr] & 1)) | 2;
+   context->if_value = _evaluate_if_stack(context);
+
+   return 0;
+}
+
+int
+sl_pp_process_if(struct sl_pp_context *context,
+                 const struct sl_pp_token_info *input,
+                 unsigned int first,
+                 unsigned int last)
+{
+   return _parse_if(context, input, first, last);
+}
+
+int
+sl_pp_process_ifdef(struct sl_pp_context *context,
+                    const struct sl_pp_token_info *input,
+                    unsigned int first,
+                    unsigned int last)
+{
+   unsigned int i;
+
+   if (!context->if_ptr) {
+      /* #if nesting too deep. */
+      return -1;
+   }
+
+   for (i = first; i < last; i++) {
+      switch (input[i].token) {
+      case SL_PP_IDENTIFIER:
+         {
+            struct sl_pp_macro *macro;
+            int macro_name = input[i].data.identifier;
+            int defined = 0;
+
+            for (macro = context->macro; macro; macro = macro->next) {
+               if (macro->name == macro_name) {
+                  defined = 1;
+                  break;
+               }
+            }
+
+            context->if_ptr--;
+            context->if_stack[context->if_ptr] = defined ? 1 : 0;
+            context->if_value = _evaluate_if_stack(context);
+         }
+         return 0;
+
+      case SL_PP_WHITESPACE:
+         break;
+
+      default:
+         /* Expected an identifier. */
+         return -1;
+      }
+   }
+
+   /* Expected an identifier. */
+   return -1;
+}
+
+int
+sl_pp_process_ifndef(struct sl_pp_context *context,
+                     const struct sl_pp_token_info *input,
+                     unsigned int first,
+                     unsigned int last)
+{
+   unsigned int i;
+
+   if (!context->if_ptr) {
+      /* #if nesting too deep. */
+      return -1;
+   }
+
+   for (i = first; i < last; i++) {
+      switch (input[i].token) {
+      case SL_PP_IDENTIFIER:
+         {
+            struct sl_pp_macro *macro;
+            int macro_name = input[i].data.identifier;
+            int defined = 0;
+
+            for (macro = context->macro; macro; macro = macro->next) {
+               if (macro->name == macro_name) {
+                  defined = 1;
+                  break;
+               }
+            }
+
+            context->if_ptr--;
+            context->if_stack[context->if_ptr] = defined ? 0 : 1;
+            context->if_value = _evaluate_if_stack(context);
+         }
+         return 0;
+
+      case SL_PP_WHITESPACE:
+         break;
+
+      default:
+         /* Expected an identifier. */
+         return -1;
+      }
+   }
+
+   /* Expected an identifier. */
+   return -1;
+}
+
+int
+sl_pp_process_elif(struct sl_pp_context *context,
+                   const struct sl_pp_token_info *input,
+                   unsigned int first,
+                   unsigned int last)
+{
+   if (_parse_else(context)) {
+      return -1;
+   }
+
+   if (context->if_stack[context->if_ptr] & 1) {
+      context->if_ptr++;
+      if (_parse_if(context, input, first, last)) {
+         return -1;
+      }
+   }
+
+   /* We are still in the #if block. */
+   context->if_stack[context->if_ptr] = context->if_stack[context->if_ptr] & ~2;
+
+   return 0;
+}
+
+int
+sl_pp_process_else(struct sl_pp_context *context,
+                   const struct sl_pp_token_info *input,
+                   unsigned int first,
+                   unsigned int last)
+{
+   return _parse_else(context);
+}
+
+int
+sl_pp_process_endif(struct sl_pp_context *context,
+                    const struct sl_pp_token_info *input,
+                    unsigned int first,
+                    unsigned int last)
+{
+   if (context->if_ptr == SL_PP_MAX_IF_NESTING) {
+      /* No matching #if. */
+      return -1;
+   }
+
+   context->if_ptr++;
+   context->if_value = _evaluate_if_stack(context);
+
+   return 0;
+}