glsl linker: compare interface blocks during intrastage linking

Verify that interface blocks match when combining compilation
units at the same stage. (For example, when merging all vertex
shaders.)

Fixes piglit glsl-1.50 test:
* linker/interface-blocks-multiple-vs-member-count-mismatch.shader_test

v5 (Ken): Rename to link_interface_blocks.cpp and drop the separate .h
file for consistency with other linker code.  Remove "ok" variable.
Fold cross_validate_interface_blocks into its caller.

Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>

src/glsl/Makefile.sources

@@ -46,6 +46,7 @@ LIBGLSL_FILES = \
 	$(GLSL_SRCDIR)/ir_variable_refcount.cpp \
 	$(GLSL_SRCDIR)/linker.cpp \
 	$(GLSL_SRCDIR)/link_functions.cpp \
+	$(GLSL_SRCDIR)/link_interface_blocks.cpp \
 	$(GLSL_SRCDIR)/link_uniforms.cpp \
 	$(GLSL_SRCDIR)/link_uniform_initializers.cpp \
 	$(GLSL_SRCDIR)/link_uniform_block_active_visitor.cpp \

src/glsl/link_interface_blocks.cpp

@@ -0,0 +1,71 @@
+/*
+ * Copyright © 2013 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.
+ */
+
+/**
+ * \file link_interface_blocks.cpp
+ * Linker support for GLSL's interface blocks.
+ */
+
+#include "ir.h"
+#include "glsl_symbol_table.h"
+#include "linker.h"
+#include "main/macros.h"
+
+bool
+validate_intrastage_interface_blocks(const gl_shader **shader_list,
+                                     unsigned num_shaders)
+{
+   glsl_symbol_table interfaces;
+
+   for (unsigned int i = 0; i < num_shaders; i++) {
+      if (shader_list[i] == NULL)
+         continue;
+
+      foreach_list(node, shader_list[i]->ir) {
+         ir_variable *var = ((ir_instruction *) node)->as_variable();
+         if (!var)
+            continue;
+
+         const glsl_type *iface_type = var->interface_type;
+
+         if (iface_type == NULL)
+            continue;
+
+         const glsl_type *old_iface_type =
+            interfaces.get_interface(iface_type->name,
+                                     (enum ir_variable_mode) var->mode);
+
+         if (old_iface_type == NULL) {
+            /* This is the first time we've seen the interface, so save
+             * it into our symbol table.
+             */
+            interfaces.add_interface(iface_type->name, iface_type,
+                                     (enum ir_variable_mode) var->mode);
+         } else if (old_iface_type != iface_type) {
+            return false;
+         }
+      }
+   }
+
+   return true;
+}

src/glsl/linker.cpp

@@ -938,6 +938,12 @@ link_intrastage_shaders(void *mem_ctx,
    if (!cross_validate_globals(prog, shader_list, num_shaders, false))
       return NULL;
 
+   /* Check that interface blocks defined in multiple shaders are consistent.
+    */
+   if (!validate_intrastage_interface_blocks((const gl_shader **)shader_list,
+                                             num_shaders))
+      return NULL;
+
    /* Check that uniform blocks between shaders for a stage agree. */
    const int num_uniform_blocks =
       link_uniform_blocks(mem_ctx, prog, shader_list, num_shaders,

src/glsl/linker.h

@@ -60,6 +60,10 @@ link_uniform_blocks(void *mem_ctx,
                     unsigned num_shaders,
                     struct gl_uniform_block **blocks_ret);
 
+bool
+validate_intrastage_interface_blocks(const gl_shader **shader_list,
+                                     unsigned num_shaders);
+
 /**
  * Class for processing all of the leaf fields of a variable that corresponds
  * to a program resource.