Rename .cc files to .cpp

1 files changed, 187 insertions, 0 deletions

diff --git a/hir_field_selection.cpp b/hir_field_selection.cpp
new file mode 100644
index 0000000000..295cbaf894
--- /dev/null
+++ b/hir_field_selection.cpp
@@ -0,0 +1,187 @@
+/*
+ * 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 "main/imports.h"
+#include "symbol_table.h"
+#include "glsl_parser_extras.h"
+#include "ast.h"
+#include "glsl_types.h"
+#include "ir.h"
+
+#define X 1
+#define R 5
+#define S 9
+#define I 13
+
+static bool
+generate_swizzle(const char *str, struct ir_swizzle_mask *swiz,
+		 unsigned vector_length)
+{
+   /* For each possible swizzle character, this table encodes the value in
+    * \c idx_map that represents the 0th element of the vector.  For invalid
+    * swizzle characters (e.g., 'k'), a special value is used that will allow
+    * detection of errors.
+    */
+   unsigned char base_idx[26] = {
+   /* a  b  c  d  e  f  g  h  i  j  k  l  m */
+      R, R, I, I, I, I, R, I, I, I, I, I, I,
+   /* n  o  p  q  r  s  t  u  v  w  x  y  z */
+      I, I, S, S, R, S, S, I, I, X, X, X, X
+   };
+
+   /* Each valid swizzle character has an entry in the previous table.  This
+    * table encodes the base index encoded in the previous table plus the actual
+    * index of the swizzle character.  When processing swizzles, the first
+    * character in the string is indexed in the previous table.  Each character
+    * in the string is indexed in this table, and the value found there has the
+    * value form the first table subtracted.  The result must be on the range
+    * [0,3].
+    *
+    * For example, the string "wzyx" will get X from the first table.  Each of
+    * the charcaters will get X+3, X+2, X+1, and X+0 from this table.  After
+    * subtraction, the swizzle values are { 3, 2, 1, 0 }.
+    *
+    * The string "wzrg" will get X from the first table.  Each of the characters
+    * will get X+3, X+2, R+0, and R+1 from this table.  After subtraction, the
+    * swizzle values are { 3, 2, 4, 5 }.  Since 4 and 5 are outside the range
+    * [0,3], the error is detected.
+    */
+   unsigned char idx_map[26] = {
+   /* a    b    c    d    e    f    g    h    i    j    k    l    m */
+      R+3, R+2, 0,   0,   0,   0,   R+1, 0,   0,   0,   0,   0,   0,
+   /* n    o    p    q    r    s    t    u    v    w    x    y    z */
+      0,   0,   S+2, S+3, R+0, S+0, S+1, 0,   0,   X+3, X+0, X+1, X+2
+   };
+
+   int swiz_idx[4] = { 0, 0, 0, 0 };
+   unsigned base;
+   unsigned dup_mask = 0;
+   unsigned seen_mask = 0;
+   unsigned i;
+
+
+   /* Validate the first character in the swizzle string and look up the base
+    * index value as described above.
+    */
+   if ((str[0] < 'a') || (str[0] > 'z'))
+      return FALSE;
+
+   base = base_idx[str[0] - 'a'];
+
+
+   for (i = 0; (i < 4) && (str[i] != '\0'); i++) {
+      unsigned bit;
+
+      /* Validate the next character, and, as described above, convert it to a
+       * swizzle index.
+       */
+      if ((str[i] < 'a') || (str[i] > 'z'))
+	 return FALSE;
+
+      swiz_idx[i] = idx_map[str[0] - 'a'] - base;
+      if ((swiz_idx[i] < 0) || (swiz_idx[i] >= (int) vector_length))
+	 return FALSE;
+
+
+      /* Track a bit-mask of the swizzle index values that have been seen.  If
+       * a value is seen more than once, set the "duplicate" flag.
+       */
+      bit = (1U << swiz_idx[i]);
+      dup_mask |= seen_mask & bit;
+      seen_mask |= bit;
+   }
+
+   if (str[i] != '\0')
+	 return FALSE;
+
+   swiz->x = swiz_idx[0];
+   swiz->y = swiz_idx[1];
+   swiz->z = swiz_idx[2];
+   swiz->w = swiz_idx[3];
+   swiz->num_components = i;
+   swiz->has_duplicates = (dup_mask != 0);
+
+   return TRUE;
+}
+
+
+struct ir_instruction *
+_mesa_ast_field_selection_to_hir(const ast_expression *expr,
+				 simple_node *instructions,
+				 struct _mesa_glsl_parse_state *state)
+{
+   ir_instruction *op;
+   ir_dereference *deref;
+   YYLTYPE loc;
+
+
+   op = _mesa_ast_to_hir(expr->subexpressions[0], instructions, state);
+   deref = new ir_dereference(op);
+
+   /* Initially assume that the resulting type of the field selection is an
+    * error.  This make the error paths below a bit easier to follow.
+    */
+   deref->type = glsl_error_type;
+
+   /* If processing the thing being dereferenced generated an error, bail out
+    * now.  Doing so prevents spurious error messages from being logged below.
+    */
+   if (is_error_type(op->type))
+      return (struct ir_instruction *) deref;
+
+   /* There are two kinds of field selection.  There is the selection of a
+    * specific field from a structure, and there is the selection of a
+    * swizzle / mask from a vector.  Which is which is determined entirely
+    * by the base type of the thing to which the field selection operator is
+    * being applied.
+    */
+   _mesa_ast_get_location(expr, & loc);
+   if (is_glsl_type_vector(op->type)) {
+      if (generate_swizzle(expr->primary_expression.identifier, 
+			   & deref->selector.swizzle,
+			   op->type->vector_elements)) {
+	 /* Based on the number of elements in the swizzle and the base type
+	  * (i.e., float, int, unsigned, or bool) of the vector being swizzled,
+	  * generate the type of the resulting value.
+	  */
+	 deref->type =
+	    _mesa_glsl_get_vector_type(op->type->base_type,
+				       deref->selector.swizzle.num_components);
+      } else {
+	 /* FINISHME: Logging of error messages should be moved into
+	  * FINISHME: generate_swizzle.  This allows the generation of more
+	  * FINISHME: specific error messages.
+	  */
+	 _mesa_glsl_error(& loc, state, "Invalid swizzle / mask `%s'",
+			  expr->primary_expression.identifier);
+      }
+   } else if (op->type->base_type == GLSL_TYPE_STRUCT) {
+      /* FINISHME: Handle field selection from structures. */
+   } else {
+      _mesa_glsl_error(& loc, state, "Cannot access field `%s' of "
+		       "non-structure / non-vector.",
+		       expr->primary_expression.identifier);
+   }
+
+   return (struct ir_instruction *) deref;
+}