From 7f377879fc526dfb69966ed1672d3036e807235c Mon Sep 17 00:00:00 2001
From: Giovanni Mascellani <gmascellani@codeweavers.com>
Date: Wed, 12 Nov 2025 13:43:59 +0100
Subject: [PATCH] vkd3d-shader/spirv: Clamp push constant CBV sizes to those of
 the push constant ranges backing them.

Otherwise invalid SPIR-V may be generated, because the CBV field in
"push_cb_struct" may end up overlapping with a subsequent one.
---
 libs/vkd3d-shader/spirv.c                | 13 +++++++++----
 libs/vkd3d-shader/vkd3d_shader_private.h |  1 +
 tests/hlsl/descriptors.shader_test       |  2 +-
 3 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/libs/vkd3d-shader/spirv.c b/libs/vkd3d-shader/spirv.c
index 5ebbefe5f..2f5dbe8c0 100644
--- a/libs/vkd3d-shader/spirv.c
+++ b/libs/vkd3d-shader/spirv.c
@@ -6668,13 +6668,18 @@ static void spirv_compiler_emit_cbv_declaration(struct spirv_compiler *compiler,
         /* Push constant buffers are handled in
          * spirv_compiler_emit_push_constant_buffers().
          */
-        push_cb->reg = reg;
-        push_cb->size = size;
         if (size_in_bytes > push_cb->pc.size)
         {
-            WARN("Constant buffer size %u exceeds push constant size %u.\n",
-                    size_in_bytes, push_cb->pc.size);
+            spirv_compiler_warning(compiler, VKD3D_SHADER_WARNING_SPV_INVALID_SIZE,
+                    "Constant buffer cb%u, space %u, has size %u which exceeds the push constant size %u.",
+                    push_cb->pc.register_index, push_cb->pc.register_space, size_in_bytes, push_cb->pc.size);
+            size_in_bytes = push_cb->pc.size;
+            size = align(size_in_bytes, VKD3D_VEC4_SIZE * sizeof(uint32_t));
+            size /= VKD3D_VEC4_SIZE * sizeof(uint32_t);
         }
+
+        push_cb->reg = reg;
+        push_cb->size = size;
         return;
     }
 
diff --git a/libs/vkd3d-shader/vkd3d_shader_private.h b/libs/vkd3d-shader/vkd3d_shader_private.h
index 6802f4ed2..524aa5e6c 100644
--- a/libs/vkd3d-shader/vkd3d_shader_private.h
+++ b/libs/vkd3d-shader/vkd3d_shader_private.h
@@ -110,6 +110,7 @@ enum vkd3d_shader_error
     VKD3D_SHADER_WARNING_SPV_INVALID_SWIZZLE            = 2300,
     VKD3D_SHADER_WARNING_SPV_INVALID_UAV_FLAGS          = 2301,
     VKD3D_SHADER_WARNING_SPV_IGNORING_FLAG              = 2302,
+    VKD3D_SHADER_WARNING_SPV_INVALID_SIZE               = 2303,
 
     VKD3D_SHADER_ERROR_RS_OUT_OF_MEMORY                 = 3000,
     VKD3D_SHADER_ERROR_RS_INVALID_VERSION               = 3001,
diff --git a/tests/hlsl/descriptors.shader_test b/tests/hlsl/descriptors.shader_test
index 033125523..3c8541259 100644
--- a/tests/hlsl/descriptors.shader_test
+++ b/tests/hlsl/descriptors.shader_test
@@ -22,7 +22,7 @@ float4 main() : SV_Target
 
 [test]
 uniform 0 float4 1.0 2.0 3.0 4.0
-todo(d3d12 & !windows & !mvk) draw quad
+draw quad
 probe (0, 0) f32(2.0, 3.0, 4.0, 5.0)
 
 [require]