[PATCH 0/2] MR302: vkd3d-shader/hlsl: Allow 'const' modifier without initializer in the global scope.

[Nikolay Sivov (＠nsivov)]

Signed-off-by: Nikolay Sivov

[PATCH 1/2] tests: Add some tests for a 'const' modifier.

[Nikolay Sivov]

From: Nikolay Sivov

Signed-off-by: Nikolay Sivov 
---
 Makefile.am                  |  1 +
 tests/hlsl/const.shader_test | 21 +++++++++++++++++++++
 2 files changed, 22 insertions(+)
 create mode 100644 tests/hlsl/const.shader_test

diff --git a/Makefile.am b/Makefile.am
index 27738f3b..ad007d8f 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -74,6 +74,7 @@ vkd3d_shader_tests = \
    tests/hlsl/comma.shader_test \
    tests/hlsl/compute.shader_test \
    tests/hlsl/conditional.shader_test \
+	tests/hlsl/const.shader_test \
    tests/hlsl/cross.shader_test \
    tests/hlsl/d3dcolor-to-ubyte4.shader_test \
    tests/hlsl/ddxddy.shader_test \
diff --git a/tests/hlsl/const.shader_test b/tests/hlsl/const.shader_test
new file mode 100644
index 00000000..ff89791e
--- /dev/null
+++ b/tests/hlsl/const.shader_test
@@ -0,0 +1,21 @@
+[pixel shader todo]
+const float4 f1;
+const uniform float4 f2;
+
+float4 main() : sv_target
+{
+    return f1 + f2;
+}
+
+[test]
+uniform 0 float4 1.0 2.0 3.0 4.0
+uniform 4 float4 0.1 0.2 0.3 0.4
+todo draw quad
+todo probe all rgba (1.1, 2.2, 3.3, 4.4)
+
+[pixel shader fail]
+float4 main() : sv_target
+{
+    const float f;
+    return 0;
+}

[PATCH 2/2] vkd3d-shader/hlsl: Allow 'const' modifier without initializer in the global scope.

[Nikolay Sivov]

From: Nikolay Sivov

Signed-off-by: Nikolay Sivov 
---
 libs/vkd3d-shader/hlsl.y     | 15 ++++++---------
 tests/hlsl/const.shader_test |  6 +++---
 2 files changed, 9 insertions(+), 12 deletions(-)

diff --git a/libs/vkd3d-shader/hlsl.y b/libs/vkd3d-shader/hlsl.y
index 0d994673..29e0ff0c 100644
--- a/libs/vkd3d-shader/hlsl.y
+++ b/libs/vkd3d-shader/hlsl.y
@@ -2131,6 +2131,12 @@ static void declare_var(struct hlsl_ctx *ctx, struct parse_variable_def *v)
         if (var->semantic.name)
             hlsl_error(ctx, &var->loc, VKD3D_SHADER_ERROR_HLSL_INVALID_SEMANTIC,
                     "Semantics are not allowed on local variables.");
+
+        if ((type->modifiers & HLSL_MODIFIER_CONST) && !v->initializer.args_count && !(modifiers & HLSL_STORAGE_STATIC))
+        {
+            hlsl_error(ctx, &v->loc, VKD3D_SHADER_ERROR_HLSL_MISSING_INITIALIZER,
+                "Const variable "%s" is missing an initializer.", var->name);
+        }
     }

if ((var->storage_modifiers & HLSL_STORAGE_STATIC) && type_has_numeric_components(var->data_type)
@@ -2140,15 +2146,6 @@ static void declare_var(struct hlsl_ctx *ctx, struct parse_variable_def *v)
                 "Static variables cannot have both numeric and resource components.");
     }

-    if ((type->modifiers & HLSL_MODIFIER_CONST) && !v->initializer.args_count
-            && !(modifiers & (HLSL_STORAGE_STATIC | HLSL_STORAGE_UNIFORM)))
-    {
-        hlsl_error(ctx, &v->loc, VKD3D_SHADER_ERROR_HLSL_MISSING_INITIALIZER,
-                "Const variable "%s" is missing an initializer.", var->name);
-        hlsl_free_var(var);
-        return;
-    }
-
     if (!hlsl_add_var(ctx, var, local))
     {
         struct hlsl_ir_var *old = hlsl_get_var(ctx->cur_scope, var->name);
diff --git a/tests/hlsl/const.shader_test b/tests/hlsl/const.shader_test
index ff89791e..ed5899f6 100644
--- a/tests/hlsl/const.shader_test
+++ b/tests/hlsl/const.shader_test
@@ -1,4 +1,4 @@
-[pixel shader todo]
+[pixel shader]
 const float4 f1;
 const uniform float4 f2;

@@ -10,8 +10,8 @@ float4 main() : sv_target
 [test]
 uniform 0 float4 1.0 2.0 3.0 4.0
 uniform 4 float4 0.1 0.2 0.3 0.4
-todo draw quad
-todo probe all rgba (1.1, 2.2, 3.3, 4.4)
+draw quad
+probe all rgba (1.1, 2.2, 3.3, 4.4)

[pixel shader fail]
 float4 main() : sv_target

[Francisco Casas (＠fcasas)]

I find no problem with the series. Maybe I would add a test for const arguments, but that doesn't stop working because of the changes:

```hlsl
float4 main(const float a : SEM) : sv_target
{
    return a + 1;
}
```

By the way, this a little silly, but it seems that while native compiler doesn't allow to assign to a const lhs with `=`, it surprisingly does allow assignments with operators such as `+=`. The value is not updated in this case though:

```hlsl
float4 main() : sv_target
{
    const float4 f = {1, 2, 3, 4};

f += 3;
    return f;
}
```
```
ps_4_0
dcl_output o0.xyzw
mov o0.xyzw, l(1.000000,2.000000,3.000000,4.000000)
ret
```

[PATCH 0/2] MR302: vkd3d-shader/hlsl: Allow 'const' modifier without initializer in the global scope. - approved

[Francisco Casas (＠fcasas)]

This merge request was approved by Francisco Casas.

[PATCH 0/2] MR302: vkd3d-shader/hlsl: Allow 'const' modifier without initializer in the global scope. - approved

[Zebediah Figura (＠zfigura)]

This merge request was approved by Zebediah Figura.

[PATCH 0/2] MR302: vkd3d-shader/hlsl: Allow 'const' modifier without initializer in the global scope. - approved

[Giovanni Mascellani (＠giomasce)]

This merge request was approved by Giovanni Mascellani.

[PATCH 0/2] MR302: vkd3d-shader/hlsl: Allow 'const' modifier without initializer in the global scope. - approved

[Henri Verbeet (＠hverbeet)]

This merge request was approved by Henri Verbeet.