mesa: set the gl_FragDepth layout in the GLSL linker

Reviewed-by: Kenneth Graunke <[email protected]>
Reviewed-by: Ian Romanick <[email protected]>

4 files changed, 61 insertions, 46 deletions

diff --git a/src/glsl/linker.cpp b/src/glsl/linker.cpp
index 0ec773d6cd2..35270881af5 100644
--- a/src/glsl/linker.cpp
+++ b/src/glsl/linker.cpp
@@ -1876,6 +1876,57 @@ store_tfeedback_info(struct gl_context *ctx, struct gl_shader_program *prog,
 }
 
 /**
+ * Store the gl_FragDepth layout in the gl_shader_program struct.
+ */
+static void
+store_fragdepth_layout(struct gl_shader_program *prog)
+{
+   if (prog->_LinkedShaders[MESA_SHADER_FRAGMENT] == NULL) {
+      return;
+   }
+
+   struct exec_list *ir = prog->_LinkedShaders[MESA_SHADER_FRAGMENT]->ir;
+
+   /* We don't look up the gl_FragDepth symbol directly because if
+    * gl_FragDepth is not used in the shader, it's removed from the IR.
+    * However, the symbol won't be removed from the symbol table.
+    *
+    * We're only interested in the cases where the variable is NOT removed
+    * from the IR.
+    */
+   foreach_list(node, ir) {
+      ir_variable *const var = ((ir_instruction *) node)->as_variable();
+
+      if (var == NULL || var->mode != ir_var_out) {
+         continue;
+      }
+
+      if (strcmp(var->name, "gl_FragDepth") == 0) {
+         switch (var->depth_layout) {
+         case ir_depth_layout_none:
+            prog->FragDepthLayout = FRAG_DEPTH_LAYOUT_NONE;
+            return;
+         case ir_depth_layout_any:
+            prog->FragDepthLayout = FRAG_DEPTH_LAYOUT_ANY;
+            return;
+         case ir_depth_layout_greater:
+            prog->FragDepthLayout = FRAG_DEPTH_LAYOUT_GREATER;
+            return;
+         case ir_depth_layout_less:
+            prog->FragDepthLayout = FRAG_DEPTH_LAYOUT_LESS;
+            return;
+         case ir_depth_layout_unchanged:
+            prog->FragDepthLayout = FRAG_DEPTH_LAYOUT_UNCHANGED;
+            return;
+         default:
+            assert(0);
+            return;
+         }
+      }
+   }
+}
+
+/**
  * Validate the resources used by a program versus the implementation limits
  */
 static bool
@@ -2177,6 +2228,7 @@ link_shaders(struct gl_context *ctx, struct gl_shader_program *prog)
 
    update_array_sizes(prog);
    link_assign_uniform_locations(prog);
+   store_fragdepth_layout(prog);
 
    if (!check_resources(ctx, prog))
       goto done;
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index 285ec0783da..b3427dac17d 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -2218,6 +2218,9 @@ struct gl_shader_program
    /** Post-link transform feedback info. */
    struct gl_transform_feedback_info LinkedTransformFeedback;
 
+   /** Post-link gl_FragDepth layout for ARB_conservative_depth. */
+   enum gl_frag_depth_layout FragDepthLayout;
+
    /** Geometry shader state - copied into gl_geometry_program at link time */
    struct {
       GLint VerticesOut;
diff --git a/src/mesa/program/ir_to_mesa.cpp b/src/mesa/program/ir_to_mesa.cpp
index 5cee8377811..5a68fc51d08 100644
--- a/src/mesa/program/ir_to_mesa.cpp
+++ b/src/mesa/program/ir_to_mesa.cpp
@@ -685,29 +685,6 @@ ir_to_mesa_visitor::visit(ir_variable *ir)
 
       fp->OriginUpperLeft = ir->origin_upper_left;
       fp->PixelCenterInteger = ir->pixel_center_integer;
-
-   } else if (strcmp(ir->name, "gl_FragDepth") == 0) {
-      struct gl_fragment_program *fp = (struct gl_fragment_program *)this->prog;
-      switch (ir->depth_layout) {
-      case ir_depth_layout_none:
-	 fp->FragDepthLayout = FRAG_DEPTH_LAYOUT_NONE;
-	 break;
-      case ir_depth_layout_any:
-	 fp->FragDepthLayout = FRAG_DEPTH_LAYOUT_ANY;
-	 break;
-      case ir_depth_layout_greater:
-	 fp->FragDepthLayout = FRAG_DEPTH_LAYOUT_GREATER;
-	 break;
-      case ir_depth_layout_less:
-	 fp->FragDepthLayout = FRAG_DEPTH_LAYOUT_LESS;
-	 break;
-      case ir_depth_layout_unchanged:
-	 fp->FragDepthLayout = FRAG_DEPTH_LAYOUT_UNCHANGED;
-	 break;
-      default:
-	 assert(0);
-	 break;
-      }
    }
 
    if (ir->mode == ir_var_uniform && strncmp(ir->name, "gl_", 3) == 0) {
@@ -3222,6 +3199,12 @@ get_mesa_program(struct gl_context *ctx,
    do_set_program_inouts(shader->ir, prog, shader->Type == GL_FRAGMENT_SHADER);
    count_resources(prog);
 
+   /* Set the gl_FragDepth layout. */
+   if (target == GL_FRAGMENT_PROGRAM_ARB) {
+      struct gl_fragment_program *fp = (struct gl_fragment_program *)prog;
+      fp->FragDepthLayout = shader_program->FragDepthLayout;
+   }
+
    _mesa_reference_program(ctx, &shader->Program, prog);
 
    if ((ctx->Shader.Flags & GLSL_NO_OPT) == 0) {
diff --git a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
index 0bf6766f72d..929c7af01ce 100644
--- a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
+++ b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
@@ -1017,29 +1017,6 @@ glsl_to_tgsi_visitor::visit(ir_variable *ir)
 
       fp->OriginUpperLeft = ir->origin_upper_left;
       fp->PixelCenterInteger = ir->pixel_center_integer;
-
-   } else if (strcmp(ir->name, "gl_FragDepth") == 0) {
-      struct gl_fragment_program *fp = (struct gl_fragment_program *)this->prog;
-      switch (ir->depth_layout) {
-      case ir_depth_layout_none:
-         fp->FragDepthLayout = FRAG_DEPTH_LAYOUT_NONE;
-         break;
-      case ir_depth_layout_any:
-         fp->FragDepthLayout = FRAG_DEPTH_LAYOUT_ANY;
-         break;
-      case ir_depth_layout_greater:
-         fp->FragDepthLayout = FRAG_DEPTH_LAYOUT_GREATER;
-         break;
-      case ir_depth_layout_less:
-         fp->FragDepthLayout = FRAG_DEPTH_LAYOUT_LESS;
-         break;
-      case ir_depth_layout_unchanged:
-         fp->FragDepthLayout = FRAG_DEPTH_LAYOUT_UNCHANGED;
-         break;
-      default:
-         assert(0);
-         break;
-      }
    }
 
    if (ir->mode == ir_var_uniform && strncmp(ir->name, "gl_", 3) == 0) {