xwininfo libX11 mesa mkfontscale xserver git updated 8 June 2014

xserver          commit e27a839bf0488d5b1cc2e2a887f2ea0e3d790790
libxcb           commit d978a4f69b30b630f28d07f1003cf290284d24d8
libxcb/xcb-proto commit 389889e2f95af19e7fc7ac89e7faeb2f28652415
xkeyboard-config commit bc3ac1b0d152e929b3532a541596cf9fe286bb9e
libX11           commit d81fed46144d089bdfa1d916a28dffc9ebffe1e4
libXdmcp         commit fe8eab93e9bcdbe8bb8052434bb5e676e3a0ee8f
libXext          commit 11aad96bd689d54156064d2e81213dc827a689d1
libfontenc       commit 0037a42107b952c9d903719615747e760e4e7247
libXinerama      commit edd95182b26eb5d576d4878c559e0f17dddaa909
libXau           commit 1e4635be11154dd8262f37b379511bd627defa2a
xkbcomp          commit d4e02a09258063c6d024c3ccd42d6b22212e6e18
pixman           commit 9cd283b2eb8279824406bfd47b020d21fc00cf82
xextproto        commit 66afec3f49e8eb0d4c2e9af7088fc3116d4bafd7
randrproto       commit a4a6694c059d74247c16527eef4a0ec9f56bbef6
glproto          commit f84853d97d5749308992412a215fa518b6536eb3
mkfontscale      commit 48e541dc2f2fc3f4e99d3e168c28241ff5adff4d
xwininfo         commit 017b3736489985999d8dcf4d9e473e1fd6dd3647
libXft           commit 214f9b5306d833e2787c75fe41dfdc9228fcb738
libXmu           commit 22d9c590901e121936f50dee97dc60c4f7defb63
libxtrans        commit a57a7f62242e1ea972b81414741729bf3dbae0a4
fontconfig       commit f44bfad235e63bb792c38e16ae1fbd281ec1453b
mesa             commit eb58aa9cf015e79a0fcf2e088676e6aa1d5dabce

1 files changed, 184 insertions, 15 deletions

diff --git a/mesalib/src/glsl/ir_function.cpp b/mesalib/src/glsl/ir_function.cpp
index 40cf5894a..deec1dfe8 100644
--- a/mesalib/src/glsl/ir_function.cpp
+++ b/mesalib/src/glsl/ir_function.cpp
@@ -23,6 +23,7 @@
 
 #include "glsl_types.h"
 #include "ir.h"
+#include "glsl_parser_extras.h"
 
 typedef enum {
    PARAMETER_LIST_NO_MATCH,
@@ -38,7 +39,8 @@ typedef enum {
  * \see matching_signature()
  */
 static parameter_list_match_t
-parameter_lists_match(const exec_list *list_a, const exec_list *list_b)
+parameter_lists_match(_mesa_glsl_parse_state *state,
+                      const exec_list *list_a, const exec_list *list_b)
 {
    const exec_node *node_a = list_a->head;
    const exec_node *node_b = list_b->head;
@@ -79,12 +81,12 @@ parameter_lists_match(const exec_list *list_a, const exec_list *list_b)
 
       case ir_var_const_in:
       case ir_var_function_in:
-	 if (!actual->type->can_implicitly_convert_to(param->type))
+	 if (!actual->type->can_implicitly_convert_to(param->type, state))
 	    return PARAMETER_LIST_NO_MATCH;
 	 break;
 
       case ir_var_function_out:
-	 if (!param->type->can_implicitly_convert_to(actual->type))
+	 if (!param->type->can_implicitly_convert_to(actual->type, state))
 	    return PARAMETER_LIST_NO_MATCH;
 	 break;
 
@@ -115,6 +117,168 @@ parameter_lists_match(const exec_list *list_a, const exec_list *list_b)
 }
 
 
+/* Classes of parameter match, sorted (mostly) best matches first.
+ * See is_better_parameter_match() below for the exceptions.
+ * */
+typedef enum {
+   PARAMETER_EXACT_MATCH,
+   PARAMETER_FLOAT_TO_DOUBLE,
+   PARAMETER_INT_TO_FLOAT,
+   PARAMETER_INT_TO_DOUBLE,
+   PARAMETER_OTHER_CONVERSION,
+} parameter_match_t;
+
+
+static parameter_match_t
+get_parameter_match_type(const ir_variable *param,
+                         const ir_rvalue *actual)
+{
+   const glsl_type *from_type;
+   const glsl_type *to_type;
+
+   if (param->data.mode == ir_var_function_out) {
+      from_type = param->type;
+      to_type = actual->type;
+   } else {
+      from_type = actual->type;
+      to_type = param->type;
+   }
+
+   if (from_type == to_type)
+      return PARAMETER_EXACT_MATCH;
+
+   /* XXX: When ARB_gpu_shader_fp64 support is added, check for float->double,
+    * and int/uint->double conversions
+    */
+
+   if (to_type->base_type == GLSL_TYPE_FLOAT)
+      return PARAMETER_INT_TO_FLOAT;
+
+   /* int -> uint and any other oddball conversions */
+   return PARAMETER_OTHER_CONVERSION;
+}
+
+
+static bool
+is_better_parameter_match(parameter_match_t a_match,
+                          parameter_match_t b_match)
+{
+   /* From section 6.1 of the GLSL 4.00 spec (and the ARB_gpu_shader5 spec):
+    *
+    * 1. An exact match is better than a match involving any implicit
+    * conversion.
+    *
+    * 2. A match involving an implicit conversion from float to double
+    * is better than match involving any other implicit conversion.
+    *
+    * [XXX: Not in GLSL 4.0: Only in ARB_gpu_shader5:
+    * 3. A match involving an implicit conversion from either int or uint
+    * to float is better than a match involving an implicit conversion
+    * from either int or uint to double.]
+    *
+    * If none of the rules above apply to a particular pair of conversions,
+    * neither conversion is considered better than the other.
+    *
+    * --
+    *
+    * Notably, the int->uint conversion is *not* considered to be better
+    * or worse than int/uint->float or int/uint->double.
+    */
+
+   if (a_match >= PARAMETER_INT_TO_FLOAT && b_match == PARAMETER_OTHER_CONVERSION)
+      return false;
+
+   return a_match < b_match;
+}
+
+
+static bool
+is_best_inexact_overload(const exec_list *actual_parameters,
+                         ir_function_signature **matches,
+                         int num_matches,
+                         ir_function_signature *sig)
+{
+   /* From section 6.1 of the GLSL 4.00 spec (and the ARB_gpu_shader5 spec):
+    *
+    * "A function definition A is considered a better
+    * match than function definition B if:
+    *
+    *   * for at least one function argument, the conversion for that argument
+    *     in A is better than the corresponding conversion in B; and
+    *
+    *   * there is no function argument for which the conversion in B is better
+    *     than the corresponding conversion in A.
+    *
+    * If a single function definition is considered a better match than every
+    * other matching function definition, it will be used.  Otherwise, a
+    * semantic error occurs and the shader will fail to compile."
+    */
+   for (ir_function_signature **other = matches;
+        other < matches + num_matches; other++) {
+      if (*other == sig)
+         continue;
+
+      const exec_node *node_a = sig->parameters.head;
+      const exec_node *node_b = (*other)->parameters.head;
+      const exec_node *node_p = actual_parameters->head;
+
+      bool better_for_some_parameter = false;
+
+      for (/* empty */
+           ; !node_a->is_tail_sentinel()
+           ; node_a = node_a->next,
+             node_b = node_b->next,
+             node_p = node_p->next) {
+         parameter_match_t a_match = get_parameter_match_type(
+               (const ir_variable *)node_a,
+               (const ir_rvalue *)node_p);
+         parameter_match_t b_match = get_parameter_match_type(
+               (const ir_variable *)node_b,
+               (const ir_rvalue *)node_p);
+
+         if (is_better_parameter_match(a_match, b_match))
+               better_for_some_parameter = true;
+
+         if (is_better_parameter_match(b_match, a_match))
+               return false;     /* B is better for this parameter */
+      }
+
+      if (!better_for_some_parameter)
+         return false;     /* A must be better than B for some parameter */
+
+   }
+
+   return true;
+}
+
+
+static ir_function_signature *
+choose_best_inexact_overload(_mesa_glsl_parse_state *state,
+                             const exec_list *actual_parameters,
+                             ir_function_signature **matches,
+                             int num_matches)
+{
+   if (num_matches == 0)
+      return NULL;
+
+   if (num_matches == 1)
+      return *matches;
+
+   /* Without GLSL 4.0 / ARB_gpu_shader5, there is no overload resolution
+    * among multiple inexact matches. Note that state may be NULL here if
+    * called from the linker; in that case we assume everything supported in
+    * any GLSL version is available. */
+   if (!state || state->is_version(400, 0) || state->ARB_gpu_shader5_enable) {
+      for (ir_function_signature **sig = matches; sig < matches + num_matches; sig++) {
+         if (is_best_inexact_overload(actual_parameters, matches, num_matches, *sig))
+            return *sig;
+      }
+   }
+
+   return NULL;   /* no best candidate */
+}
+
+
 ir_function_signature *
 ir_function::matching_signature(_mesa_glsl_parse_state *state,
                                 const exec_list *actual_parameters)
@@ -126,10 +290,11 @@ ir_function::matching_signature(_mesa_glsl_parse_state *state,
 ir_function_signature *
 ir_function::matching_signature(_mesa_glsl_parse_state *state,
                                 const exec_list *actual_parameters,
-			        bool *is_exact)
+                                bool *is_exact)
 {
+   ir_function_signature **inexact_matches = NULL;
    ir_function_signature *match = NULL;
-   bool multiple_inexact_matches = false;
+   int num_inexact_matches = 0;
 
    /* From page 42 (page 49 of the PDF) of the GLSL 1.20 spec:
     *
@@ -148,16 +313,19 @@ ir_function::matching_signature(_mesa_glsl_parse_state *state,
       if (sig->is_builtin() && !sig->is_builtin_available(state))
          continue;
 
-      switch (parameter_lists_match(& sig->parameters, actual_parameters)) {
+      switch (parameter_lists_match(state, & sig->parameters, actual_parameters)) {
       case PARAMETER_LIST_EXACT_MATCH:
-	 *is_exact = true;
-	 return sig;
+         *is_exact = true;
+         free(inexact_matches);
+         return sig;
       case PARAMETER_LIST_INEXACT_MATCH:
-	 if (match == NULL)
-	    match = sig;
-	 else
-	    multiple_inexact_matches = true;
-	 continue;
+         inexact_matches = (ir_function_signature **)
+               realloc(inexact_matches,
+                       sizeof(*inexact_matches) *
+                       (num_inexact_matches + 1));
+         assert(inexact_matches);
+         inexact_matches[num_inexact_matches++] = sig;
+         continue;
       case PARAMETER_LIST_NO_MATCH:
 	 continue;
       default:
@@ -175,9 +343,10 @@ ir_function::matching_signature(_mesa_glsl_parse_state *state,
     */
    *is_exact = false;
 
-   if (multiple_inexact_matches)
-      return NULL;
+   match = choose_best_inexact_overload(state, actual_parameters,
+                                        inexact_matches, num_inexact_matches);
 
+   free(inexact_matches);
    return match;
 }