[HLSL][RootSiganture] Add parsing of new number params in StaticSampler #140291

inbelic · 2025-05-16T18:19:29Z

defines in-memory reprsentation of maxAnisotropy, minLOD and maxLOD
integrates parsing of these number parameters with their respective, parseUInt and parseFloat respectively
adds basic unit tests to demonstrate setting functionality

Part 3 of #126574

llvmbot · 2025-05-16T18:20:06Z

@llvm/pr-subscribers-hlsl

@llvm/pr-subscribers-clang

Author: Finn Plummer (inbelic)

Changes

defines in-memory reprsentation of maxAnisotropy, minLOD and maxLOD
integrates parsing of these number parameters with their respective, parseUInt and parseFloat respectively
adds basic unit tests to demonstrate setting functionality

Part 3 of #126574

Full diff: https://github.com/llvm/llvm-project/pull/140291.diff

6 Files Affected:

(modified) clang/include/clang/Lex/HLSLRootSignatureTokenKinds.def (+3)
(modified) clang/include/clang/Parse/ParseHLSLRootSignature.h (+3)
(modified) clang/lib/Parse/ParseHLSLRootSignature.cpp (+60)
(modified) clang/unittests/Lex/LexHLSLRootSignatureTest.cpp (+1-1)
(modified) clang/unittests/Parse/ParseHLSLRootSignatureTest.cpp (+20-2)
(modified) llvm/include/llvm/Frontend/HLSL/HLSLRootSignature.h (+3)

diff --git a/clang/include/clang/Lex/HLSLRootSignatureTokenKinds.def b/clang/include/clang/Lex/HLSLRootSignatureTokenKinds.def
index 5d16eaa5b72f6..7ca131349fed4 100644
--- a/clang/include/clang/Lex/HLSLRootSignatureTokenKinds.def
+++ b/clang/include/clang/Lex/HLSLRootSignatureTokenKinds.def
@@ -102,6 +102,9 @@ KEYWORD(offset)
 
 // StaticSampler Keywords:
 KEYWORD(mipLODBias)
+KEYWORD(maxAnisotropy)
+KEYWORD(minLOD)
+KEYWORD(maxLOD)
 
 // Unbounded Enum:
 UNBOUNDED_ENUM(unbounded, "unbounded")
diff --git a/clang/include/clang/Parse/ParseHLSLRootSignature.h b/clang/include/clang/Parse/ParseHLSLRootSignature.h
index c12b022a030ef..e62d5de948a44 100644
--- a/clang/include/clang/Parse/ParseHLSLRootSignature.h
+++ b/clang/include/clang/Parse/ParseHLSLRootSignature.h
@@ -112,6 +112,9 @@ class RootSignatureParser {
   struct ParsedStaticSamplerParams {
     std::optional<llvm::hlsl::rootsig::Register> Reg;
     std::optional<float> MipLODBias;
+    std::optional<uint32_t> MaxAnisotropy;
+    std::optional<float> MinLOD;
+    std::optional<float> MaxLOD;
   };
   std::optional<ParsedStaticSamplerParams> parseStaticSamplerParams();
 
diff --git a/clang/lib/Parse/ParseHLSLRootSignature.cpp b/clang/lib/Parse/ParseHLSLRootSignature.cpp
index db2e922160062..04fe8d00f25cd 100644
--- a/clang/lib/Parse/ParseHLSLRootSignature.cpp
+++ b/clang/lib/Parse/ParseHLSLRootSignature.cpp
@@ -384,6 +384,15 @@ std::optional<StaticSampler> RootSignatureParser::parseStaticSampler() {
   if (Params->MipLODBias.has_value())
     Sampler.MipLODBias = Params->MipLODBias.value();
 
+  if (Params->MaxAnisotropy.has_value())
+    Sampler.MaxAnisotropy = Params->MaxAnisotropy.value();
+
+  if (Params->MinLOD.has_value())
+    Sampler.MinLOD = Params->MinLOD.value();
+
+  if (Params->MaxLOD.has_value())
+    Sampler.MaxLOD = Params->MaxLOD.value();
+
   if (consumeExpectedToken(TokenKind::pu_r_paren,
                            diag::err_hlsl_unexpected_end_of_params,
                            /*param of=*/TokenKind::kw_StaticSampler))
@@ -686,6 +695,57 @@ RootSignatureParser::parseStaticSamplerParams() {
         return std::nullopt;
       Params.MipLODBias = (float)*MipLODBias;
     }
+
+    // `maxAnisotropy` `=` POS_INT
+    if (tryConsumeExpectedToken(TokenKind::kw_maxAnisotropy)) {
+      if (Params.MaxAnisotropy.has_value()) {
+        getDiags().Report(CurToken.TokLoc, diag::err_hlsl_rootsig_repeat_param)
+            << CurToken.TokKind;
+        return std::nullopt;
+      }
+
+      if (consumeExpectedToken(TokenKind::pu_equal))
+        return std::nullopt;
+
+      auto MaxAnisotropy = parseUIntParam();
+      if (!MaxAnisotropy.has_value())
+        return std::nullopt;
+      Params.MaxAnisotropy = MaxAnisotropy;
+    }
+
+    // `minLOD` `=` NUMBER
+    if (tryConsumeExpectedToken(TokenKind::kw_minLOD)) {
+      if (Params.MinLOD.has_value()) {
+        getDiags().Report(CurToken.TokLoc, diag::err_hlsl_rootsig_repeat_param)
+            << CurToken.TokKind;
+        return std::nullopt;
+      }
+
+      if (consumeExpectedToken(TokenKind::pu_equal))
+        return std::nullopt;
+
+      auto MinLOD = parseFloatParam();
+      if (!MinLOD.has_value())
+        return std::nullopt;
+      Params.MinLOD = MinLOD;
+    }
+
+    // `maxLOD` `=` NUMBER
+    if (tryConsumeExpectedToken(TokenKind::kw_maxLOD)) {
+      if (Params.MaxLOD.has_value()) {
+        getDiags().Report(CurToken.TokLoc, diag::err_hlsl_rootsig_repeat_param)
+            << CurToken.TokKind;
+        return std::nullopt;
+      }
+
+      if (consumeExpectedToken(TokenKind::pu_equal))
+        return std::nullopt;
+
+      auto MaxLOD = parseFloatParam();
+      if (!MaxLOD.has_value())
+        return std::nullopt;
+      Params.MaxLOD = MaxLOD;
+    }
   } while (tryConsumeExpectedToken(TokenKind::pu_comma));
 
   return Params;
diff --git a/clang/unittests/Lex/LexHLSLRootSignatureTest.cpp b/clang/unittests/Lex/LexHLSLRootSignatureTest.cpp
index b610b8f10f8da..575a97e75a05d 100644
--- a/clang/unittests/Lex/LexHLSLRootSignatureTest.cpp
+++ b/clang/unittests/Lex/LexHLSLRootSignatureTest.cpp
@@ -136,7 +136,7 @@ TEST_F(LexHLSLRootSignatureTest, ValidLexAllTokensTest) {
     space visibility flags
     numDescriptors offset
 
-    mipLODBias
+    mipLODBias maxAnisotropy minLOD maxLOD
 
     unbounded
     DESCRIPTOR_RANGE_OFFSET_APPEND
diff --git a/clang/unittests/Parse/ParseHLSLRootSignatureTest.cpp b/clang/unittests/Parse/ParseHLSLRootSignatureTest.cpp
index 539232e0bf2c2..94e0464ddf03b 100644
--- a/clang/unittests/Parse/ParseHLSLRootSignatureTest.cpp
+++ b/clang/unittests/Parse/ParseHLSLRootSignatureTest.cpp
@@ -225,7 +225,11 @@ TEST_F(ParseHLSLRootSignatureTest, ValidParseDTClausesTest) {
 
 TEST_F(ParseHLSLRootSignatureTest, ValidParseStaticSamplerTest) {
   const llvm::StringLiteral Source = R"cc(
-    StaticSampler(s0, mipLODBias = 0)
+    StaticSampler(s0),
+    StaticSampler(s0, maxAnisotropy = 3,
+      minLOD = 4.2f, mipLODBias = 0.23e+3,
+      maxLOD = 9000,
+    )
   )cc";
 
   TrivialModuleLoader ModLoader;
@@ -241,13 +245,27 @@ TEST_F(ParseHLSLRootSignatureTest, ValidParseStaticSamplerTest) {
 
   ASSERT_FALSE(Parser.parse());
 
-  ASSERT_EQ(Elements.size(), 1u);
+  ASSERT_EQ(Elements.size(), 2u);
 
+  // Check default values are as expected
   RootElement Elem = Elements[0];
   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).MipLODBias, 0.f);
+  ASSERT_EQ(std::get<StaticSampler>(Elem).MaxAnisotropy, 16u);
+  ASSERT_EQ(std::get<StaticSampler>(Elem).MinLOD, 0.f);
+  ASSERT_EQ(std::get<StaticSampler>(Elem).MaxLOD, 3.402823466e+38f);
+
+  // Check values can be set as expected
+  Elem = Elements[1];
+  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).MipLODBias, 230.f);
+  ASSERT_EQ(std::get<StaticSampler>(Elem).MaxAnisotropy, 3u);
+  ASSERT_EQ(std::get<StaticSampler>(Elem).MinLOD, 4.2f);
+  ASSERT_EQ(std::get<StaticSampler>(Elem).MaxLOD, 9000.f);
 
   ASSERT_TRUE(Consumer->isSatisfied());
 }
diff --git a/llvm/include/llvm/Frontend/HLSL/HLSLRootSignature.h b/llvm/include/llvm/Frontend/HLSL/HLSLRootSignature.h
index 6b4da48a302bc..8ee58b87f5e49 100644
--- a/llvm/include/llvm/Frontend/HLSL/HLSLRootSignature.h
+++ b/llvm/include/llvm/Frontend/HLSL/HLSLRootSignature.h
@@ -161,6 +161,9 @@ struct DescriptorTableClause {
 struct StaticSampler {
   Register Reg;
   float MipLODBias = 0.f;
+  uint32_t MaxAnisotropy = 16;
+  float MinLOD = 0.f;
+  float MaxLOD = 3.402823466e+38f; // FLT_MAX
 };
 
 /// Models RootElement : RootFlags | RootConstants | RootParam

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

clang/unittests/Parse/ParseHLSLRootSignatureTest.cpp

…er (#140291) - defines in-memory reprsentation of `maxAnisotropy`, `minLOD` and `maxLOD` - integrates parsing of these number parameters with their respective, `parseUInt` and `parseFloat` respectively - adds basic unit tests to demonstrate setting functionality Part 3 of #126574

…er (llvm#140291) - defines in-memory reprsentation of `maxAnisotropy`, `minLOD` and `maxLOD` - integrates parsing of these number parameters with their respective, `parseUInt` and `parseFloat` respectively - adds basic unit tests to demonstrate setting functionality Part 3 of llvm#126574

llvmbot added clang Clang issues not falling into any other category clang:frontend Language frontend issues, e.g. anything involving "Sema" HLSL HLSL Language Support labels May 16, 2025

inbelic linked an issue May 16, 2025 that may be closed by this pull request

[HLSL] Implement Root Signature Parsing of Static Samplers #126574

Closed

4 tasks

joaosaffran approved these changes May 26, 2025

View reviewed changes

joaosaffran reviewed May 26, 2025

View reviewed changes

llvm/include/llvm/Frontend/HLSL/HLSLRootSignature.h Outdated Show resolved Hide resolved

joaosaffran reviewed May 26, 2025

View reviewed changes

clang/unittests/Parse/ParseHLSLRootSignatureTest.cpp Outdated Show resolved Hide resolved

bogner approved these changes May 27, 2025

View reviewed changes

clang/unittests/Parse/ParseHLSLRootSignatureTest.cpp Outdated Show resolved Hide resolved

inbelic added 9 commits May 29, 2025 18:00

pre-req: add keywords

4002195

add parsing for maxAnisotropy

caa9a93

add parsing for minLOD

2ff0c01

add parsing for maxLOD

36dab3b

add testing of setting parameters

017407d

format

a7c4a37

review: use EXPECT_FLOAT_EQ

194df3f

review: use defined FLT_MAX

10af071

review: add missed ASSERT_FLOAT_EQ

c7b1673

inbelic changed the base branch from users/inbelic/pr-140181 to main May 29, 2025 18:02

inbelic force-pushed the inbelic/rs-numbers-sampler branch from 30f8bdd to c7b1673 Compare May 29, 2025 18:03

inbelic merged commit c8eb094 into llvm:main May 29, 2025
9 of 11 checks passed

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

[HLSL][RootSiganture] Add parsing of new number params in StaticSampler #140291

[HLSL][RootSiganture] Add parsing of new number params in StaticSampler #140291

inbelic commented May 16, 2025

Uh oh!

llvmbot commented May 16, 2025 •

edited

Loading

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

[HLSL][RootSiganture] Add parsing of new number params in StaticSampler #140291

[HLSL][RootSiganture] Add parsing of new number params in StaticSampler #140291

Conversation

inbelic commented May 16, 2025

Uh oh!

llvmbot commented May 16, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

llvmbot commented May 16, 2025 •

edited

Loading