glsl: During linking, record whether a GS uses EndPrimitive().

This information will be useful in the i965 back end, since we can
save some compilation effort if we know from the outset that the
shader never calls EndPrimitive().

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

src/glsl/linker.cpp

@@ -249,6 +249,33 @@ public:
 };
 
 
+/**
+ * Visitor that determines whether or not a shader uses ir_end_primitive.
+ */
+class find_end_primitive_visitor : public ir_hierarchical_visitor {
+public:
+   find_end_primitive_visitor()
+      : found(false)
+   {
+      /* empty */
+   }
+
+   virtual ir_visitor_status visit(ir_end_primitive *)
+   {
+      found = true;
+      return visit_stop;
+   }
+
+   bool end_primitive_found()
+   {
+      return found;
+   }
+
+private:
+   bool found;
+};
+
+
 void
 linker_error(gl_shader_program *prog, const char *fmt, ...)
 {
@@ -517,6 +544,10 @@ validate_geometry_shader_executable(struct gl_shader_program *prog,
 
    analyze_clip_usage("geometry", prog, shader, &prog->Geom.UsesClipDistance,
                       &prog->Geom.ClipDistanceArraySize);
+
+   find_end_primitive_visitor end_primitive;
+   end_primitive.run(shader->ir);
+   prog->Geom.UsesEndPrimitive = end_primitive.end_primitive_found();
 }
 
 

src/mesa/main/mtypes.h

@@ -1931,6 +1931,7 @@ struct gl_geometry_program
                            GL_TRIANGLES, or GL_TRIANGLES_ADJACENCY_ARB */
    GLenum OutputType; /**< GL_POINTS, GL_LINE_STRIP or GL_TRIANGLE_STRIP */
    GLboolean UsesClipDistance;
+   GLboolean UsesEndPrimitive;
 };
 
 
@@ -2364,6 +2365,7 @@ struct gl_shader_program
       GLboolean UsesClipDistance;
       GLuint ClipDistanceArraySize; /**< Size of the gl_ClipDistance array, or
                                          0 if not present. */
+      GLboolean UsesEndPrimitive;
    } Geom;
 
    /** Vertex shader state */

src/mesa/main/shaderapi.c

@@ -1872,6 +1872,7 @@ _mesa_copy_linked_program_data(gl_shader_type type,
       dst_gp->InputType = src->Geom.InputType;
       dst_gp->OutputType = src->Geom.OutputType;
       dst_gp->UsesClipDistance = src->Geom.UsesClipDistance;
+      dst_gp->UsesEndPrimitive = src->Geom.UsesEndPrimitive;
    }
       break;
    default: