reland fix: rename Filter to SamplerFilter

- there were many compilations failures when using gcc due to naming
ambiguity of using Filter Filter in StaticSampler
- this commit removes the ambiguity by renaming Filter to SamplerFilter
- this fix has been verified locally using both clang and gcc for
compilation of commit

Author: inbelic

clang/include/clang/Parse/ParseHLSLRootSignature.h

@@ -111,7 +111,7 @@ class RootSignatureParser {
 
   struct ParsedStaticSamplerParams {
     std::optional<llvm::hlsl::rootsig::Register> Reg;
-    std::optional<llvm::hlsl::rootsig::Filter> Filter;
+    std::optional<llvm::hlsl::rootsig::SamplerFilter> Filter;
     std::optional<llvm::hlsl::rootsig::TextureAddressMode> AddressU;
     std::optional<llvm::hlsl::rootsig::TextureAddressMode> AddressV;
     std::optional<llvm::hlsl::rootsig::TextureAddressMode> AddressW;
@@ -133,7 +133,7 @@ class RootSignatureParser {
 
   /// Parsing methods of various enums
   std::optional<llvm::hlsl::rootsig::ShaderVisibility> parseShaderVisibility();
-  std::optional<llvm::hlsl::rootsig::Filter> parseFilter();
+  std::optional<llvm::hlsl::rootsig::SamplerFilter> parseSamplerFilter();
   std::optional<llvm::hlsl::rootsig::TextureAddressMode>
   parseTextureAddressMode();
   std::optional<llvm::hlsl::rootsig::ComparisonFunc> parseComparisonFunc();

clang/lib/Parse/ParseHLSLRootSignature.cpp

@@ -710,7 +710,7 @@ RootSignatureParser::parseStaticSamplerParams() {
       if (consumeExpectedToken(TokenKind::pu_equal))
         return std::nullopt;
 
-      auto Filter = parseFilter();
+      auto Filter = parseSamplerFilter();
       if (!Filter.has_value())
         return std::nullopt;
       Params.Filter = Filter;
@@ -1009,7 +1009,8 @@ RootSignatureParser::parseShaderVisibility() {
   return std::nullopt;
 }
 
-std::optional<llvm::hlsl::rootsig::Filter> RootSignatureParser::parseFilter() {
+std::optional<llvm::hlsl::rootsig::SamplerFilter>
+RootSignatureParser::parseSamplerFilter() {
   assert(CurToken.TokKind == TokenKind::pu_equal &&
          "Expects to only be invoked starting at given keyword");
 
@@ -1024,7 +1025,7 @@ std::optional<llvm::hlsl::rootsig::Filter> RootSignatureParser::parseFilter() {
   switch (CurToken.TokKind) {
 #define FILTER_ENUM(NAME, LIT)                                                 \
   case TokenKind::en_##NAME:                                                   \
-    return Filter::NAME;                                                       \
+    return SamplerFilter::NAME;                                                \
     break;
 #include "clang/Lex/HLSLRootSignatureTokenKinds.def"
   default:

clang/unittests/Parse/ParseHLSLRootSignatureTest.cpp

@@ -258,7 +258,7 @@ TEST_F(ParseHLSLRootSignatureTest, ValidParseStaticSamplerTest) {
   ASSERT_TRUE(std::holds_alternative<StaticSampler>(Elem));
   ASSERT_EQ(std::get<StaticSampler>(Elem).Reg.ViewType, RegisterType::SReg);
   ASSERT_EQ(std::get<StaticSampler>(Elem).Reg.Number, 0u);
-  ASSERT_EQ(std::get<StaticSampler>(Elem).Filter, Filter::Anisotropic);
+  ASSERT_EQ(std::get<StaticSampler>(Elem).Filter, SamplerFilter::Anisotropic);
   ASSERT_EQ(std::get<StaticSampler>(Elem).AddressU, TextureAddressMode::Wrap);
   ASSERT_EQ(std::get<StaticSampler>(Elem).AddressV, TextureAddressMode::Wrap);
   ASSERT_EQ(std::get<StaticSampler>(Elem).AddressW, TextureAddressMode::Wrap);
@@ -278,7 +278,7 @@ TEST_F(ParseHLSLRootSignatureTest, ValidParseStaticSamplerTest) {
   ASSERT_EQ(std::get<StaticSampler>(Elem).Reg.ViewType, RegisterType::SReg);
   ASSERT_EQ(std::get<StaticSampler>(Elem).Reg.Number, 0u);
   ASSERT_EQ(std::get<StaticSampler>(Elem).Filter,
-            Filter::MaximumMinPointMagLinearMipPoint);
+            SamplerFilter::MaximumMinPointMagLinearMipPoint);
   ASSERT_EQ(std::get<StaticSampler>(Elem).AddressU, TextureAddressMode::Mirror);
   ASSERT_EQ(std::get<StaticSampler>(Elem).AddressV, TextureAddressMode::Border);
   ASSERT_EQ(std::get<StaticSampler>(Elem).AddressW, TextureAddressMode::Clamp);

llvm/include/llvm/Frontend/HLSL/HLSLRootSignature.h

@@ -82,7 +82,7 @@ enum class ShaderVisibility {
 
 // D3D12_FILTER enumeration:
 // https://learn.microsoft.com/en-us/windows/win32/api/d3d12/ne-d3d12-d3d12_filter
-enum class Filter {
+enum class SamplerFilter {
   MinMagMipPoint = 0,
   MinMagPointMipLinear = 0x1,
   MinPointMagLinearMipPoint = 0x4,
@@ -230,7 +230,7 @@ LLVM_ABI raw_ostream &operator<<(raw_ostream &OS,
 
 struct StaticSampler {
   Register Reg;
-  Filter Filter = Filter::Anisotropic;
+  SamplerFilter Filter = SamplerFilter::Anisotropic;
   TextureAddressMode AddressU = TextureAddressMode::Wrap;
   TextureAddressMode AddressV = TextureAddressMode::Wrap;
   TextureAddressMode AddressW = TextureAddressMode::Wrap;