[clang] Introduce SemaRISCV (#92682)

This patch moves `Sema` functions that are specific for RISC-V into the
new `SemaRISCV` class. This continues previous efforts to split `Sema`
up. Additional context can be found in
#84184.

This PR is somewhat different from previous PRs on this topic:
1. Splitting out target-specific functions wasn't previously discussed.
It felt quite natural to do, though.
2. I had to make some static function in `SemaChecking.cpp` member
functions of `Sema` in order to use them in `SemaRISCV`.
3. I dropped "RISCV" from identifiers, but decided to leave "RVV"
(RISC-V "V" vector extensions) intact. I think it's an idiomatic
abbreviation at this point, but I'm open to input from contributors in
that area.
4. I repurposed `SemaRISCVVectorLookup.cpp` for `SemaRISCV`.

I think this was a successful experiment, which both helps the goal of
splitting `Sema` up, and shows a way to approach `SemaChecking.cpp`,
which I wasn't sure how to approach before. As we move more
target-specific function out of there, we'll gradually make the checking
"framework" inside `SemaChecking.cpp` public, which is currently a whole
bunch of static functions. This would enable us to move more functions
outside of `SemaChecking.cpp`.

clang/include/clang/Sema/Sema.h

@@ -175,6 +175,7 @@ class SemaObjC;
 class SemaOpenACC;
 class SemaOpenMP;
 class SemaPseudoObject;
+class SemaRISCV;
 class SemaSYCL;
 class StandardConversionSequence;
 class Stmt;
@@ -491,7 +492,6 @@ class Sema final : public SemaBase {
   // 29. Constraints and Concepts (SemaConcept.cpp)
   // 30. Types (SemaType.cpp)
   // 31. FixIt Helpers (SemaFixItUtils.cpp)
-  // 32. Name Lookup for RISC-V Vector Intrinsic (SemaRISCVVectorLookup.cpp)
 
   /// \name Semantic Analysis
   /// Implementations are in Sema.cpp
@@ -1027,6 +1027,11 @@ class Sema final : public SemaBase {
     return *PseudoObjectPtr;
   }
 
+  SemaRISCV &RISCV() {
+    assert(RISCVPtr);
+    return *RISCVPtr;
+  }
+
   SemaSYCL &SYCL() {
     assert(SYCLPtr);
     return *SYCLPtr;
@@ -1069,6 +1074,7 @@ class Sema final : public SemaBase {
   std::unique_ptr<SemaOpenACC> OpenACCPtr;
   std::unique_ptr<SemaOpenMP> OpenMPPtr;
   std::unique_ptr<SemaPseudoObject> PseudoObjectPtr;
+  std::unique_ptr<SemaRISCV> RISCVPtr;
   std::unique_ptr<SemaSYCL> SYCLPtr;
 
   ///@}
@@ -2044,6 +2050,23 @@ class Sema final : public SemaBase {
 
   void CheckConstrainedAuto(const AutoType *AutoT, SourceLocation Loc);
 
+  bool BuiltinConstantArg(CallExpr *TheCall, int ArgNum, llvm::APSInt &Result);
+  bool BuiltinConstantArgRange(CallExpr *TheCall, int ArgNum, int Low, int High,
+                               bool RangeIsError = true);
+  bool BuiltinConstantArgMultiple(CallExpr *TheCall, int ArgNum,
+                                  unsigned Multiple);
+  bool BuiltinConstantArgPower2(CallExpr *TheCall, int ArgNum);
+  bool BuiltinConstantArgShiftedByte(CallExpr *TheCall, int ArgNum,
+                                     unsigned ArgBits);
+  bool BuiltinConstantArgShiftedByteOrXXFF(CallExpr *TheCall, int ArgNum,
+                                           unsigned ArgBits);
+
+  bool checkArgCountAtLeast(CallExpr *Call, unsigned MinArgCount);
+  bool checkArgCountAtMost(CallExpr *Call, unsigned MaxArgCount);
+  bool checkArgCountRange(CallExpr *Call, unsigned MinArgCount,
+                          unsigned MaxArgCount);
+  bool checkArgCount(CallExpr *Call, unsigned DesiredArgCount);
+
 private:
   void CheckArrayAccess(const Expr *BaseExpr, const Expr *IndexExpr,
                         const ArraySubscriptExpr *ASE = nullptr,
@@ -2112,11 +2135,7 @@ class Sema final : public SemaBase {
   bool CheckPPCBuiltinFunctionCall(const TargetInfo &TI, unsigned BuiltinID,
                                    CallExpr *TheCall);
   bool CheckAMDGCNBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
-  bool CheckRISCVLMUL(CallExpr *TheCall, unsigned ArgNum);
-  bool CheckRISCVBuiltinFunctionCall(const TargetInfo &TI, unsigned BuiltinID,
-                                     CallExpr *TheCall);
-  void checkRVVTypeSupport(QualType Ty, SourceLocation Loc, Decl *D,
-                           const llvm::StringMap<bool> &FeatureMap);
+
   bool CheckLoongArchBuiltinFunctionCall(const TargetInfo &TI,
                                          unsigned BuiltinID, CallExpr *TheCall);
   bool CheckWebAssemblyBuiltinFunctionCall(const TargetInfo &TI,
@@ -2146,16 +2165,6 @@ class Sema final : public SemaBase {
   ExprResult BuiltinNontemporalOverloaded(ExprResult TheCallResult);
   ExprResult AtomicOpsOverloaded(ExprResult TheCallResult,
                                  AtomicExpr::AtomicOp Op);
-  bool BuiltinConstantArg(CallExpr *TheCall, int ArgNum, llvm::APSInt &Result);
-  bool BuiltinConstantArgRange(CallExpr *TheCall, int ArgNum, int Low, int High,
-                               bool RangeIsError = true);
-  bool BuiltinConstantArgMultiple(CallExpr *TheCall, int ArgNum,
-                                  unsigned Multiple);
-  bool BuiltinConstantArgPower2(CallExpr *TheCall, int ArgNum);
-  bool BuiltinConstantArgShiftedByte(CallExpr *TheCall, int ArgNum,
-                                     unsigned ArgBits);
-  bool BuiltinConstantArgShiftedByteOrXXFF(CallExpr *TheCall, int ArgNum,
-                                           unsigned ArgBits);
   bool BuiltinARMSpecialReg(unsigned BuiltinID, CallExpr *TheCall, int ArgNum,
                             unsigned ExpectedFieldNum, bool AllowName);
   bool BuiltinARMMemoryTaggingCall(unsigned BuiltinID, CallExpr *TheCall);
@@ -5890,7 +5899,6 @@ class Sema final : public SemaBase {
                                        SourceLocation Loc, bool IsCompAssign);
 
   bool isValidSveBitcast(QualType srcType, QualType destType);
-  bool isValidRVVBitcast(QualType srcType, QualType destType);
 
   bool areMatrixTypesOfTheSameDimension(QualType srcTy, QualType destTy);
 
@@ -11686,27 +11694,6 @@ class Sema final : public SemaBase {
   /// Triggered by declaration-attribute processing.
   void ProcessAPINotes(Decl *D);
 
-  ///@}
-  //
-  //
-  // -------------------------------------------------------------------------
-  //
-  //
-
-  /// \name Name Lookup for RISC-V Vector Intrinsic
-  /// Implementations are in SemaRISCVVectorLookup.cpp
-  ///@{
-
-public:
-  /// Indicate RISC-V vector builtin functions enabled or not.
-  bool DeclareRISCVVBuiltins = false;
-
-  /// Indicate RISC-V SiFive vector builtin functions enabled or not.
-  bool DeclareRISCVSiFiveVectorBuiltins = false;
-
-private:
-  std::unique_ptr<sema::RISCVIntrinsicManager> RVIntrinsicManager;
-
   ///@}
 };
 
@@ -11729,9 +11716,6 @@ void Sema::PragmaStack<Sema::AlignPackInfo>::Act(SourceLocation PragmaLocation,
                                                  PragmaMsStackAction Action,
                                                  llvm::StringRef StackSlotLabel,
                                                  AlignPackInfo Value);
-
-std::unique_ptr<sema::RISCVIntrinsicManager>
-CreateRISCVIntrinsicManager(Sema &S);
 } // end namespace clang
 
 #endif

clang/include/clang/Sema/SemaRISCV.h

@@ -0,0 +1,52 @@
+//===----- SemaRISCV.h ---- RISC-V target-specific routines ---*- C++ -*---===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+/// \file
+/// This file declares semantic analysis functions specific to RISC-V.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_SEMA_SEMARISCV_H
+#define LLVM_CLANG_SEMA_SEMARISCV_H
+
+#include "clang/AST/DeclBase.h"
+#include "clang/AST/Expr.h"
+#include "clang/AST/Type.h"
+#include "clang/Basic/SourceLocation.h"
+#include "clang/Basic/TargetInfo.h"
+#include "clang/Sema/RISCVIntrinsicManager.h"
+#include "clang/Sema/SemaBase.h"
+#include "llvm/ADT/StringMap.h"
+#include <memory>
+
+namespace clang {
+class SemaRISCV : public SemaBase {
+public:
+  SemaRISCV(Sema &S);
+
+  bool CheckLMUL(CallExpr *TheCall, unsigned ArgNum);
+  bool CheckBuiltinFunctionCall(const TargetInfo &TI, unsigned BuiltinID,
+                                CallExpr *TheCall);
+  void checkRVVTypeSupport(QualType Ty, SourceLocation Loc, Decl *D,
+                           const llvm::StringMap<bool> &FeatureMap);
+
+  bool isValidRVVBitcast(QualType srcType, QualType destType);
+
+  /// Indicate RISC-V vector builtin functions enabled or not.
+  bool DeclareRVVBuiltins = false;
+
+  /// Indicate RISC-V SiFive vector builtin functions enabled or not.
+  bool DeclareSiFiveVectorBuiltins = false;
+
+  std::unique_ptr<sema::RISCVIntrinsicManager> IntrinsicManager;
+};
+
+std::unique_ptr<sema::RISCVIntrinsicManager>
+CreateRISCVIntrinsicManager(Sema &S);
+} // namespace clang
+
+#endif // LLVM_CLANG_SEMA_SEMARISCV_H

clang/lib/Parse/ParsePragma.cpp

@@ -23,6 +23,7 @@
 #include "clang/Sema/Scope.h"
 #include "clang/Sema/SemaCUDA.h"
 #include "clang/Sema/SemaCodeCompletion.h"
+#include "clang/Sema/SemaRISCV.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/StringSwitch.h"
 #include <optional>
@@ -4154,7 +4155,7 @@ void PragmaRISCVHandler::HandlePragma(Preprocessor &PP,
   }
 
   if (II->isStr("vector"))
-    Actions.DeclareRISCVVBuiltins = true;
+    Actions.RISCV().DeclareRVVBuiltins = true;
   else if (II->isStr("sifive_vector"))
-    Actions.DeclareRISCVSiFiveVectorBuiltins = true;
+    Actions.RISCV().DeclareSiFiveVectorBuiltins = true;
 }

clang/lib/Sema/Sema.cpp

@@ -50,6 +50,7 @@
 #include "clang/Sema/SemaOpenACC.h"
 #include "clang/Sema/SemaOpenMP.h"
 #include "clang/Sema/SemaPseudoObject.h"
+#include "clang/Sema/SemaRISCV.h"
 #include "clang/Sema/SemaSYCL.h"
 #include "clang/Sema/TemplateDeduction.h"
 #include "clang/Sema/TemplateInstCallback.h"
@@ -212,6 +213,7 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
       OpenACCPtr(std::make_unique<SemaOpenACC>(*this)),
       OpenMPPtr(std::make_unique<SemaOpenMP>(*this)),
       PseudoObjectPtr(std::make_unique<SemaPseudoObject>(*this)),
+      RISCVPtr(std::make_unique<SemaRISCV>(*this)),
       SYCLPtr(std::make_unique<SemaSYCL>(*this)),
       MSPointerToMemberRepresentationMethod(
           LangOpts.getMSPointerToMemberRepresentationMethod()),
@@ -2051,7 +2053,7 @@ void Sema::checkTypeSupport(QualType Ty, SourceLocation Loc, ValueDecl *D) {
     if (TI.hasRISCVVTypes() && Ty->isRVVSizelessBuiltinType() && FD) {
       llvm::StringMap<bool> CallerFeatureMap;
       Context.getFunctionFeatureMap(CallerFeatureMap, FD);
-      checkRVVTypeSupport(Ty, Loc, D, CallerFeatureMap);
+      RISCV().checkRVVTypeSupport(Ty, Loc, D, CallerFeatureMap);
     }
 
     // Don't allow SVE types in functions without a SVE target.

clang/lib/Sema/SemaCast.cpp

@@ -25,6 +25,7 @@
 #include "clang/Sema/Initialization.h"
 #include "clang/Sema/SemaInternal.h"
 #include "clang/Sema/SemaObjC.h"
+#include "clang/Sema/SemaRISCV.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringExtras.h"
 #include <set>
@@ -2391,7 +2392,7 @@ static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr,
     }
 
     // Allow bitcasting between SVE VLATs and VLSTs, and vice-versa.
-    if (Self.isValidRVVBitcast(SrcType, DestType)) {
+    if (Self.RISCV().isValidRVVBitcast(SrcType, DestType)) {
       Kind = CK_BitCast;
       return TC_Success;
     }
@@ -3002,7 +3003,7 @@ void CastOperation::CheckCStyleCast() {
 
   // Allow bitcasting between compatible RVV vector types.
   if ((SrcType->isVectorType() || DestType->isVectorType()) &&
-      Self.isValidRVVBitcast(SrcType, DestType)) {
+      Self.RISCV().isValidRVVBitcast(SrcType, DestType)) {
     Kind = CK_BitCast;
     return;
   }