Remove warning about unspecified vkbinding

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

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

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

Closes issue #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)]]
       ^~~~~~~