[openmp] Remove OMPConstants.cpp and replace it by OMP.cpp generated by tablegen

[clementval]

Summary

Diff D83176 moved the last piece of code from OMPConstants.cpp and now this file was only
useful to include the tablegen generated file. This patch replace OMPConstants.cpp with OMP.cpp
generated by tablegen.

[clementval]

llvm/lib/Frontend/OpenMP/CMakeLists.txt

2

The reason to have renamed OMP.cpp.inc to OMP.cpp is that now it is directly source of a library and the name OMP.cpp.inc will be used to generated code pieces that have to be included in clang/flang.

[sstefan1]

Thanks for figuring this out!

LGTM.

llvm/include/llvm/Frontend/Directive/DirectiveBase.td

class DirectiveLanguage {
   string clausePrefix = "";
 
   // Make the enum values available in the namespace. This allows us to
   // write something like Enum_X if we have a `using namespace cppNamespace`.
   bit makeEnumAvailableInNamespace = 0;
 
   // Generate include and macro to enable LLVM BitmaskEnum.
   bit enableBitmaskEnumInNamespace = 0;
+
+  // Header file included in the implementation code generated. Ususally the
+  // output file of the declaration code generation. Can be left blank.
+  string includeHeader = "";
 }
 
 // Information about a specific clause.
 class Clause<string c> {
   // Name of the clause.
   string name = c;
 
   // Define an alternative name return in get<LanguageName>ClauseName function.

llvm/include/llvm/Frontend/OpenMP/CMakeLists.txt

 set(LLVM_TARGET_DEFINITIONS OMP.td)
 tablegen(LLVM OMP.h.inc --gen-directive-decl)
-tablegen(LLVM OMP.cpp.inc --gen-directive-impl)
 add_public_tablegen_target(omp_gen)

llvm/include/llvm/Frontend/OpenMP/OMP.td

 
 def OpenMP : DirectiveLanguage {
   let name = "OpenMP";
   let cppNamespace = "omp"; // final namespace will be llvm::omp
   let directivePrefix = "OMPD_";
   let clausePrefix = "OMPC_";
   let makeEnumAvailableInNamespace = 1;
   let enableBitmaskEnumInNamespace = 1;
+  let includeHeader = "llvm/Frontend/OpenMP/OMP.h.inc";
 }
 
 //===----------------------------------------------------------------------===//
 // Definition of OpenMP clauses
 //===----------------------------------------------------------------------===//
 
 def OMPC_Allocator : Clause<"allocator"> {
   let clangClass = "OMPAllocatorClause";

llvm/lib/Frontend/OpenMP/CMakeLists.txt

+set(LLVM_TARGET_DEFINITIONS ${LLVM_MAIN_INCLUDE_DIR}/llvm/Frontend/OpenMP/OMP.td)
+tablegen(LLVM OMP.cpp --gen-directive-impl)
+add_public_tablegen_target(omp_cpp)
+
 add_llvm_component_library(LLVMFrontendOpenMP
-  OMPConstants.cpp
+  OMP.cpp # Generated by tablegen above
   OMPContext.cpp
   OMPIRBuilder.cpp
 
   ADDITIONAL_HEADER_DIRS
   ${LLVM_MAIN_INCLUDE_DIR}/llvm/Frontend
   ${LLVM_MAIN_INCLUDE_DIR}/llvm/Frontend/OpenMP
 
   DEPENDS
   intrinsics_gen
   omp_gen
-  )
+  omp_cpp
+  )
 No newline at end of file

llvm/lib/Frontend/OpenMP/OMPConstants.cpp

-//===- OMPConstants.cpp - Helpers related to OpenMP code generation ---===//
-//
-// 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
-//
-//===----------------------------------------------------------------------===//
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Frontend/OpenMP/OMPConstants.h"
-
-#include "llvm/ADT/StringRef.h"
-#include "llvm/ADT/StringSwitch.h"
-#include "llvm/IR/Module.h"
-#include "llvm/IR/Type.h"
-
-using namespace llvm;
-using namespace omp;
-
-#include "llvm/Frontend/OpenMP/OMP.cpp.inc"

llvm/test/TableGen/directive1.td

 // CHECK-NEXT:  /// Return true if \p C is a valid clause for \p D in version \p Version.
 // CHECK-NEXT:  bool isAllowedClauseForDirective(Directive D, Clause C, unsigned Version);
 // CHECK-EMPTY:
 // CHECK-NEXT:  } // namespace tdl
 // CHECK-NEXT:  } // namespace llvm
 // CHECK-NEXT:  #endif // LLVM_Tdl_INC
 
 
-// IMPL:       Directive llvm::tdl::getTdlDirectiveKind(llvm::StringRef Str) {
+// IMPL:       #include "llvm/ADT/StringRef.h"
+// IMPL-NEXT:  #include "llvm/ADT/StringSwitch.h"
+// IMPL-EMPTY:
+// IMPL-NEXT:  using namespace llvm;
+// IMPL-NEXT:  using namespace tdl;
+// IMPL-EMPTY:
+// IMPL-NEXT:  Directive llvm::tdl::getTdlDirectiveKind(llvm::StringRef Str) {
 // IMPL-NEXT:    return llvm::StringSwitch<Directive>(Str)
 // IMPL-NEXT:      .Case("dira",TDLD_dira)
 // IMPL-NEXT:      .Default(TDLD_dira);
 // IMPL-NEXT:  }
 // IMPL-EMPTY:
 // IMPL-NEXT:  llvm::StringRef llvm::tdl::getTdlDirectiveName(Directive Kind) {
 // IMPL-NEXT:    switch (Kind) {
 // IMPL-NEXT:      case TDLD_dira:

llvm/test/TableGen/directive2.td

 // RUN: llvm-tblgen -gen-directive-decl -I %p/../../include %s | FileCheck -match-full-lines %s
 // RUN: llvm-tblgen -gen-directive-impl -I %p/../../include %s | FileCheck -match-full-lines %s -check-prefix=IMPL
 
 include "llvm/Frontend/Directive/DirectiveBase.td"
 
 def TestDirectiveLanguage : DirectiveLanguage {
   let name = "Tdl";
 
   let cppNamespace = "tdl";
   let directivePrefix = "TDLD_";
   let clausePrefix = "TDLC_";
+  let includeHeader = "tdl.h.inc";
 }
 
 def TDLC_ClauseA : Clause<"clausea"> {
   let isImplicit = 1;
 }
 def TDLC_ClauseB : Clause<"clauseb"> {
   let isDefault = 1;
 }

 // CHECK-EMPTY:
 // CHECK-NEXT:  /// Return true if \p C is a valid clause for \p D in version \p Version.
 // CHECK-NEXT:  bool isAllowedClauseForDirective(Directive D, Clause C, unsigned Version);
 // CHECK-EMPTY:
 // CHECK-NEXT:  } // namespace tdl
 // CHECK-NEXT:  } // namespace llvm
 // CHECK-NEXT:  #endif // LLVM_Tdl_INC
 
-
+// IMPL:       #include "tdl.h.inc"
+// IMPL-EMPTY:
+// IMPL-NEXT:  #include "llvm/ADT/StringRef.h"
+// IMPL-NEXT:  #include "llvm/ADT/StringSwitch.h"
+// IMPL-EMPTY:
+// IMPL-NEXT:  using namespace llvm;
+// IMPL-NEXT:  using namespace tdl;
+// IMPL-EMPTY:
 // IMPL:       Directive llvm::tdl::getTdlDirectiveKind(llvm::StringRef Str) {
 // IMPL-NEXT:    return llvm::StringSwitch<Directive>(Str)
 // IMPL-NEXT:      .Case("dira",TDLD_dira)
 // IMPL-NEXT:      .Default(TDLD_dira);
 // IMPL-NEXT:  }
 // IMPL-EMPTY:
 // IMPL-NEXT:  llvm::StringRef llvm::tdl::getTdlDirectiveName(Directive Kind) {
 // IMPL-NEXT:    switch (Kind) {

llvm/utils/TableGen/DirectiveEmitter.cpp

void EmitDirectivesImpl(RecordKeeper &Records, raw_ostream &OS) {
   }
 
   const auto &DirectiveLanguage = DirectiveLanguages[0];
   StringRef DirectivePrefix =
       DirectiveLanguage->getValueAsString("directivePrefix");
   StringRef LanguageName = DirectiveLanguage->getValueAsString("name");
   StringRef ClausePrefix = DirectiveLanguage->getValueAsString("clausePrefix");
   StringRef CppNamespace = DirectiveLanguage->getValueAsString("cppNamespace");
+  StringRef IncludeHeader =
+      DirectiveLanguage->getValueAsString("includeHeader");
 
   const auto &Directives = Records.getAllDerivedDefinitions("Directive");
   const auto &Clauses = Records.getAllDerivedDefinitions("Clause");
 
+  if (!IncludeHeader.empty())
+    OS << "#include \"" << IncludeHeader << "\"\n\n";
+
+  OS << "#include \"llvm/ADT/StringRef.h\"\n";
+  OS << "#include \"llvm/ADT/StringSwitch.h\"\n";
+  OS << "\n";
+  OS << "using namespace llvm;\n";
+  llvm::SmallVector<StringRef, 2> Namespaces;
+  llvm::SplitString(CppNamespace, Namespaces, "::");
+  for (auto Ns : Namespaces)
+    OS << "using namespace " << Ns << ";\n";
+
   // getDirectiveKind(StringRef Str)
   GenerateGetKind(Directives, OS, "Directive", DirectivePrefix, LanguageName,
                   CppNamespace, /*ImplicitAsUnknown=*/false);
 
   // getDirectiveName(Directive Kind)
   GenerateGetName(Directives, OS, "Directive", DirectivePrefix, LanguageName,
                   CppNamespace);