Remove warning about unspecified vkbinding

It is permitted that users omit explicit [vk::binding] settings on
HLSL-style register definitions. They are just opting into the
default implicit mapping, as they would with HLSL->VK in DXC.

That does mean register IDs can clash between resources which have
different register type but the same register number.

Such a problem can be resolved either with explicit bindings
([vk::binding]) in source, or using the "-fvk-binding" slangc options
which match DXC behavior.

Closes issue shader-slang#5938

Author: cheneym2

source/slang/slang-parameter-binding.cpp

@@ -1060,22 +1060,6 @@ static void addExplicitParameterBindings_HLSL(
     }
 }
 
-static void _maybeDiagnoseMissingVulkanLayoutModifier(
-    ParameterBindingContext* context,
-    DeclRef<VarDeclBase> const& varDecl)
-{
-    // If the user didn't specify a `binding` (and optional `set`) for Vulkan,
-    // but they *did* specify a `register` for D3D, then that is probably an
-    // oversight on their part.
-    if (auto registerModifier = varDecl.getDecl()->findModifier<HLSLRegisterSemantic>())
-    {
-        getSink(context)->diagnose(
-            registerModifier,
-            Diagnostics::registerModifierButNoVulkanLayout,
-            varDecl.getName());
-    }
-}
-
 static void addExplicitParameterBindings_GLSL(
     ParameterBindingContext* context,
     RefPtr<ParameterInfo> parameterInfo,
@@ -1212,13 +1196,6 @@ static void addExplicitParameterBindings_GLSL(
         return;
 
     auto hlslToVulkanLayoutOptions = context->getTargetProgram()->getHLSLToVulkanLayoutOptions();
-    bool warnedMissingVulkanLayoutModifier = false;
-    // If we are not told how to infer bindings with a compile option, we warn
-    if (hlslToVulkanLayoutOptions == nullptr || !hlslToVulkanLayoutOptions->canInferBindings())
-    {
-        warnedMissingVulkanLayoutModifier = true;
-        _maybeDiagnoseMissingVulkanLayoutModifier(context, varDecl.as<VarDeclBase>());
-    }
 
     // We need an HLSL register semantic to to infer from
     auto hlslRegSemantic = varDecl.getDecl()->findModifier<HLSLRegisterSemantic>();
@@ -1254,21 +1231,13 @@ static void addExplicitParameterBindings_GLSL(
         return;
     }
 
-    // If inference is not enabled for this kind, we can issue a warning
-    if (hlslToVulkanLayoutOptions &&
-        !hlslToVulkanLayoutOptions->canInfer(vulkanKind, hlslInfo.space))
-    {
-        if (!warnedMissingVulkanLayoutModifier)
-        {
-            _maybeDiagnoseMissingVulkanLayoutModifier(context, varDecl.as<VarDeclBase>());
-            warnedMissingVulkanLayoutModifier = true;
-        }
-    }
 
-    if (warnedMissingVulkanLayoutModifier)
+    if (hlslToVulkanLayoutOptions == nullptr ||
+        !hlslToVulkanLayoutOptions->canInferBindings() ||
+        !hlslToVulkanLayoutOptions->canInfer(vulkanKind, hlslInfo.space))
     {
-        // If we warn due to invalid bindings and user did not set how to interpret 'hlsl style
-        // bindings', we should map `register` 1:1 with equivlent vulkan bindings.
+        // If the user did not set how to interpret 'hlsl style bindings', we should map
+        // `register` 1:1 with equivlent vulkan bindings.
         if (!hlslToVulkanLayoutOptions || hlslToVulkanLayoutOptions->getKindShiftEnabledFlags() ==
                                               HLSLToVulkanLayoutOptions::KindFlag::None)
         {

tests/diagnostics/hlsl-to-vulkan-shift-diagnostic.hlsl.expected

@@ -1,11 +1,5 @@
 result code = -1
 standard error = {
-tests/diagnostics/hlsl-to-vulkan-shift-diagnostic.hlsl(11): warning 39013: shader parameter 'c' has a 'register' specified for D3D, but no '[[vk::binding(...)]]` specified for Vulkan
-ConstantBuffer<Data> c : register(b2);
-                         ^~~~~~~~
-tests/diagnostics/hlsl-to-vulkan-shift-diagnostic.hlsl(15): warning 39013: shader parameter 'u' has a 'register' specified for D3D, but no '[[vk::binding(...)]]` specified for Vulkan
-RWStructuredBuffer<Data> u : register(u11);
-                             ^~~~~~~~
 tests/diagnostics/hlsl-to-vulkan-shift-diagnostic.hlsl(15): error 39025: conflicting vulkan inferred binding for parameter 'c' overlap is 0 and 0
 RWStructuredBuffer<Data> u : register(u11);
                          ^

tests/diagnostics/vk-bindings.slang.expected

@@ -1,8 +1,5 @@
 result code = -1
 standard error = {
-tests/diagnostics/vk-bindings.slang(6): warning 39013: shader parameter 't' has a 'register' specified for D3D, but no '[[vk::binding(...)]]` specified for Vulkan
-Texture2D t : register(t0);
-              ^~~~~~~~
 tests/diagnostics/vk-bindings.slang(14): error 39015: shader parameter 'b' consumes whole descriptor sets, so the binding must be in the form '[[vk::binding(0, ...)]]'; the non-zero binding '2' is not allowed
 [[vk::binding(2,1)]]
       ^~~~~~~