[PATCH v2 09/11] vkd3d-shader/hlsl: Check for non-static object references.

[Francisco Casas]

From: Francisco Casas

It is responsibility of the shader's programmer to ensure that
object references can be solved statically.

Resource arrays for ps_5_1 and vs_5_1 are an exception which is not
properly handled yet. They probably deserve a different object type.

Signed-off-by: Francisco Casas 
---
v2:
 - Renamed to 'check_for_non_static_object_references' to
   'validate_static_object_references'.
 - This function always returns false now.
 - Print different error messages for each case (resource or sampler).
 - Implemented note_non_static_deref_expressions() to report to the user
   the location of the expressions that could not be resolved statically.

For instance, the following shader:

---
   Texture2D tex[3];
   uniform int n;

struct foo {
       float4 p;
       Texture2D t;
   };

float4 main() : sv_target
   {
       struct foo s[3];

s[0].t = tex[0];
       s[1].t = tex[1];
       s[2].t = tex[2];
       return s[n].t.Load(0);
   }
   ---

gives the following output:

---
   test.hlsl:16:22: E5022: Loaded resource from "s" must be determinable at compile time.
   test.hlsl:16:12: Expression for loaded resource within "s" cannot be resolved statically.
   Failed to compile shader, ret -4.
   ---

- The detection of dynamic object type loads that are not used in
   resouce_loads (which cause an error in native) is left out of this patch to
   avoid multiple error messages.
---
 libs/vkd3d-shader/hlsl_codegen.c         | 47 ++++++++++++++++++++++++
 libs/vkd3d-shader/vkd3d_shader_private.h |  1 +
 tests/object-references.shader_test      |  4 +-
 3 files changed, 50 insertions(+), 2 deletions(-)

diff --git a/libs/vkd3d-shader/hlsl_codegen.c b/libs/vkd3d-shader/hlsl_codegen.c
index 7f76fce1..6c4a0eec 100644
--- a/libs/vkd3d-shader/hlsl_codegen.c
+++ b/libs/vkd3d-shader/hlsl_codegen.c
@@ -967,6 +967,51 @@ static bool copy_propagation_execute(struct hlsl_ctx *ctx, struct hlsl_block *bl
     return progress;
 }

+static void note_non_static_deref_expressions(struct hlsl_ctx *ctx, const struct hlsl_deref *deref,
+        const char *usage)
+{
+    unsigned int i;
+
+    for (i = 0; i < deref->path_len; ++i)
+    {
+        struct hlsl_ir_node *path_node = deref->path[i].node;
+
+        assert(path_node);
+        if (path_node->type != HLSL_IR_CONSTANT)
+            hlsl_note(ctx, &path_node->loc, VKD3D_SHADER_LOG_ERROR,
+                    "Expression for %s within "%s" cannot be resolved statically.",
+                    usage, deref->var->name);
+    }
+}
+
+static bool validate_static_object_references(struct hlsl_ctx *ctx, struct hlsl_ir_node *instr,
+        void *context)
+{
+    unsigned int start, count;
+
+    if (instr->type == HLSL_IR_RESOURCE_LOAD)
+    {
+        struct hlsl_ir_resource_load *load = hlsl_ir_resource_load(instr);
+
+        if (!hlsl_component_index_range_from_deref(ctx, &load->resource, &start, &count))
+        {
+            hlsl_error(ctx, &instr->loc, VKD3D_SHADER_ERROR_HLSL_NON_STATIC_OBJECT_REF,
+                    "Loaded resource from "%s" must be determinable at compile time.",
+                    load->resource.var->name);
+            note_non_static_deref_expressions(ctx, &load->resource, "loaded resource");
+        }
+        if (load->sampler.var && !hlsl_component_index_range_from_deref(ctx, &load->sampler, &start, &count))
+        {
+            hlsl_error(ctx, &instr->loc, VKD3D_SHADER_ERROR_HLSL_NON_STATIC_OBJECT_REF,
+                    "Resource load sampler from "%s" must be determinable at compile time.",
+                    load->sampler.var->name);
+            note_non_static_deref_expressions(ctx, &load->sampler, "resource load sampler");
+        }
+    }
+
+    return false;
+}
+
 static bool is_vec1(const struct hlsl_type *type)
 {
     return (type->type == HLSL_CLASS_SCALAR) || (type->type == HLSL_CLASS_VECTOR && type->dimx == 1);
@@ -2236,6 +2281,8 @@ int hlsl_emit_bytecode(struct hlsl_ctx *ctx, struct hlsl_ir_function_decl *entry
     if (ctx->profile->major_version < 4)
         transform_ir(ctx, lower_division, body, NULL);

+    transform_ir(ctx, validate_static_object_references, body, NULL);
+
     /* TODO: move forward, remove when no longer needed */
     transform_ir(ctx, transform_deref_paths_into_offsets, body, NULL);
     while (transform_ir(ctx, hlsl_fold_constant_exprs, body, NULL));
diff --git a/libs/vkd3d-shader/vkd3d_shader_private.h b/libs/vkd3d-shader/vkd3d_shader_private.h
index 8bde5523..aca5606b 100644
--- a/libs/vkd3d-shader/vkd3d_shader_private.h
+++ b/libs/vkd3d-shader/vkd3d_shader_private.h
@@ -118,6 +118,7 @@ enum vkd3d_shader_error
     VKD3D_SHADER_ERROR_HLSL_OFFSET_OUT_OF_BOUNDS        = 5019,
     VKD3D_SHADER_ERROR_HLSL_INCOMPATIBLE_PROFILE        = 5020,
     VKD3D_SHADER_ERROR_HLSL_DIVISION_BY_ZERO            = 5021,
+    VKD3D_SHADER_ERROR_HLSL_NON_STATIC_OBJECT_REF       = 5022,

VKD3D_SHADER_WARNING_HLSL_IMPLICIT_TRUNCATION       = 5300,
     VKD3D_SHADER_WARNING_HLSL_DIVISION_BY_ZERO          = 5301,
diff --git a/tests/object-references.shader_test b/tests/object-references.shader_test
index a9fbbc50..bc36777b 100644
--- a/tests/object-references.shader_test
+++ b/tests/object-references.shader_test
@@ -101,7 +101,7 @@ draw quad
 probe all rgba (2132, 2132, 2132, 1111)

-[pixel shader fail todo]
+[pixel shader fail]
 Texture2D tex[3];
 uniform int n;

@@ -121,7 +121,7 @@ float4 main() : sv_target
 }

-[pixel shader fail todo]
+[pixel shader fail]
 // Note: Only valid in shader model 5.1
 Texture2D tex[3];
 uniform int n;