[PATCH 0/1] MR529: vkd3d-shader/spirv: Decorate non-float32 non-built-in pixel shader inputs as Flat.

[PATCH 1/1] vkd3d-shader/spirv: Decorate non-float32 non-built-in pixel shader inputs as Flat.

[Conor McCarthy]

From: Conor McCarthy

As per VUID-StandaloneSpirv-Flat-04744. Not strictly a regression, but
revealed by 66cb2815f because it declares unused inputs.
---
 libs/vkd3d-shader/spirv.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/libs/vkd3d-shader/spirv.c b/libs/vkd3d-shader/spirv.c
index 45f46a91c..237dca056 100644
--- a/libs/vkd3d-shader/spirv.c
+++ b/libs/vkd3d-shader/spirv.c
@@ -4287,14 +4287,18 @@ static void spirv_compiler_decorate_builtin(struct spirv_compiler *compiler,
 }

static void spirv_compiler_emit_interpolation_decorations(struct spirv_compiler *compiler,
-        uint32_t id, enum vkd3d_shader_interpolation_mode mode)
+        enum vkd3d_shader_component_type component_type, uint32_t id, enum vkd3d_shader_interpolation_mode mode)
 {
     struct vkd3d_spirv_builder *builder = &compiler->spirv_builder;

switch (mode)
     {
         case VKD3DSIM_NONE:
-            break;
+            /* VUID-StandaloneSpirv-Flat-04744: integer or double types must be
+             * decorated 'Flat' for fragment shaders. */
+            if (compiler->shader_type != VKD3D_SHADER_TYPE_PIXEL || component_type == VKD3D_SHADER_COMPONENT_FLOAT)
+                break;
+            /* fall through */
         case VKD3DSIM_CONSTANT:
             vkd3d_spirv_build_op_decorate(builder, id, SpvDecorationFlat, NULL, 0);
             break;
@@ -4874,7 +4878,8 @@ static uint32_t spirv_compiler_emit_input(struct spirv_compiler *compiler,
         if (component_idx)
             vkd3d_spirv_build_op_decorate1(builder, input_id, SpvDecorationComponent, component_idx);

-        spirv_compiler_emit_interpolation_decorations(compiler, input_id, signature_element->interpolation_mode);
+        spirv_compiler_emit_interpolation_decorations(compiler, component_type, input_id,
+                signature_element->interpolation_mode);
     }

var_id = input_id;

[Giovanni Mascellani (＠giomasce)]

Thanks for looking into this. It wouldn't be bad to have a test that checks that constant interpolation mode is always presumed for integral PS inputs, though. I don't seem that the HLSL compiler allows it, but we could still receive a TPF PS shader with a non-constant-interpolation integral input, and I wonder whether a native driver would try to interpolate it anyway.

[PATCH 0/1] MR529: vkd3d-shader/spirv: Decorate non-float32 non-built-in pixel shader inputs as Flat. - approved

[Giovanni Mascellani (＠giomasce)]

This merge request was approved by Giovanni Mascellani.

[PATCH 0/1] MR529: vkd3d-shader/spirv: Decorate non-float32 non-built-in pixel shader inputs as Flat. - approved

[Henri Verbeet (＠hverbeet)]

This merge request was approved by Henri Verbeet.