add size constraint to hlsl matrix using language option as default.

Author: farzonl

clang/include/clang/Basic/LangOptions.def

@@ -243,6 +243,7 @@ ENUM_LANGOPT(HLSLVersion, HLSLLangStd, 16, HLSL_Unset, NotCompatible, "HLSL Vers
 LANGOPT(HLSLStrictAvailability, 1, 0, NotCompatible,
         "Strict availability diagnostic mode for HLSL built-in functions.")
 LANGOPT(HLSLSpvUseUnknownImageFormat, 1, 0, NotCompatible, "For storage images and texel buffers, sets the default format to 'Unknown' when not specified via the `vk::image_format` attribute. If this option is not used, the format is inferred from the resource's data type.")
+VALUE_LANGOPT(MaxMatrixDimension, 32, (1 << 20) - 1, NotCompatible, "maximum allowed matrix dimension")
 
 LANGOPT(CUDAIsDevice      , 1, 0, NotCompatible, "compiling for CUDA device")
 LANGOPT(CUDAAllowVariadicFunctions, 1, 0, NotCompatible, "allowing variadic functions in CUDA device code")

clang/lib/Basic/LangOptions.cpp

@@ -131,8 +131,12 @@ void LangOptions::setLangDefaults(LangOptions &Opts, Language Lang,
   Opts.NamedLoops = Std.isC2y();
 
   Opts.HLSL = Lang == Language::HLSL;
-  if (Opts.HLSL && Opts.IncludeDefaultHeader)
-    Includes.push_back("hlsl.h");
+  if (Opts.HLSL) {
+    if (Opts.IncludeDefaultHeader)
+      Includes.push_back("hlsl.h");
+    // Set maximum matrix dimension to 4 for HLSL
+    Opts.MaxMatrixDimension = 4;
+  }
 
   // Set OpenCL Version.
   Opts.OpenCL = Std.isOpenCL();

clang/lib/Sema/HLSLExternalSemaSource.cpp

@@ -159,9 +159,39 @@ void HLSLExternalSemaSource::defineHLSLMatrixAlias() {
                                                   SourceLocation(), ColsParam));
   TemplateParams.emplace_back(ColsParam);
 
-  auto *ParamList =
-      TemplateParameterList::Create(AST, SourceLocation(), SourceLocation(),
-                                    TemplateParams, SourceLocation(), nullptr);
+  const unsigned MaxMatDim = SemaPtr->getLangOpts().MaxMatrixDimension;
+  auto *MaxRow = IntegerLiteral::Create(
+      AST, llvm::APInt(AST.getIntWidth(AST.IntTy), MaxMatDim), AST.IntTy,
+      SourceLocation());
+  auto *MaxCol = IntegerLiteral::Create(
+      AST, llvm::APInt(AST.getIntWidth(AST.IntTy), MaxMatDim), AST.IntTy,
+      SourceLocation());
+
+  auto *RowsRef = DeclRefExpr::Create(
+      AST, NestedNameSpecifierLoc(), SourceLocation(), RowsParam,
+      /*RefersToEnclosingVariableOrCapture*/ false,
+      DeclarationNameInfo(RowsParam->getDeclName(), SourceLocation()),
+      AST.IntTy, VK_LValue);
+  auto *ColsRef = DeclRefExpr::Create(
+      AST, NestedNameSpecifierLoc(), SourceLocation(), ColsParam,
+      /*RefersToEnclosingVariableOrCapture*/ false,
+      DeclarationNameInfo(ColsParam->getDeclName(), SourceLocation()),
+      AST.IntTy, VK_LValue);
+
+  auto *RowsLE = BinaryOperator::Create(AST, RowsRef, MaxRow, BO_LE, AST.BoolTy,
+                                        VK_PRValue, OK_Ordinary,
+                                        SourceLocation(), FPOptionsOverride());
+  auto *ColsLE = BinaryOperator::Create(AST, ColsRef, MaxCol, BO_LE, AST.BoolTy,
+                                        VK_PRValue, OK_Ordinary,
+                                        SourceLocation(), FPOptionsOverride());
+
+  auto *RequiresExpr = BinaryOperator::Create(
+      AST, RowsLE, ColsLE, BO_LAnd, AST.BoolTy, VK_PRValue, OK_Ordinary,
+      SourceLocation(), FPOptionsOverride());
+
+  auto *ParamList = TemplateParameterList::Create(
+      AST, SourceLocation(), SourceLocation(), TemplateParams, SourceLocation(),
+      RequiresExpr);
 
   IdentifierInfo &II = AST.Idents.get("matrix", tok::TokenKind::identifier);
 

clang/test/SemaHLSL/BuiltIns/matrix-basic_types-errors.hlsl

@@ -4,5 +4,9 @@ uint64_t5x5 mat;
 // expected-error@-1  {{unknown type name 'uint64_t5x5'}}
 
 // Note: this one only fails because -fnative-half-type is not set
-uint16_t4x4 mat;
+uint16_t4x4 mat2;
 // expected-error@-1  {{unknown type name 'uint16_t4x4'}}
+
+matrix<int, 5, 5> mat3;
+// expected-error@-1 {{constraints not satisfied for alias template 'matrix' [with element = int, rows_count = 5, cols_count = 5]}}
+// expected-note@* {{because '5 <= 4' (5 <= 4) evaluated to false}}

clang/test/SemaHLSL/BuiltIns/matrix-errors.hlsl

@@ -2,7 +2,7 @@
 
 // Some bad declarations
 hlsl::matrix ShouldWorkSomeday; // expected-error{{use of alias template 'hlsl::matrix' requires template arguments}}
-// expected-note@*:* {{template declaration from hidden source: template <class element = float, int rows_count = 4, int cols_count = 4> using matrix = element __attribute__((matrix_type(rows_count, cols_count)))}}
+// expected-note@*:* {{template declaration from hidden source: template <class element = float, int rows_count = 4, int cols_count = 4> requires rows_count <= 4 && cols_count <= 4 using matrix = element __attribute__((matrix_type(rows_count, cols_count)))}}
 
 hlsl::matrix<1,1,1> BadMat; // expected-error{{template argument for template type parameter must be a type}}
 // expected-note@*:* {{template parameter from hidden source: class element = float}}
@@ -11,7 +11,7 @@ hlsl::matrix<int, float,4> AnotherBadMat; // expected-error{{template argument f
 // expected-note@*:* {{template parameter from hidden source: int rows_count = 4}}
 
 hlsl::matrix<int, 2, 3, 2> YABV; // expected-error{{too many template arguments for alias template 'matrix'}}
-// expected-note@*:* {{template declaration from hidden source: template <class element = float, int rows_count = 4, int cols_count = 4> using matrix = element __attribute__((matrix_type(rows_count, cols_count)))}}
+// expected-note@*:* {{template declaration from hidden source: template <class element = float, int rows_count = 4, int cols_count = 4> requires rows_count <= 4 && cols_count <= 4 using matrix = element __attribute__((matrix_type(rows_count, cols_count)))}}
 
 // This code is rejected by clang because clang puts the HLSL built-in types
 // into the HLSL namespace.