[PATCH 2/3] perf clang: Add support for recent clang versions

[Sandipan Das]

The clang API calls used by perf have changed in recent
releases and builds succeed with libclang-3.9 only. This
introduces compatibility with libclang-4.0 and above.

Without this patch, we will see the following compilation
errors with libclang-4.0+:

 util/c++/clang.cpp: In function âclang::CompilerInvocation* perf::createCompilerInvocation(llvm::opt::ArgStringList, llvm::StringRef&, clang::DiagnosticsEngine&)â:
 util/c++/clang.cpp:62:33: error: âIK_Câ was not declared in this scope
   Opts.Inputs.emplace_back(Path, IK_C);
                                  ^~~~
 util/c++/clang.cpp: In function âstd::unique_ptr<llvm::Module> perf::getModuleFromSource(llvm::opt::ArgStringList, llvm::StringRef, llvm::IntrusiveRefCntPtr<clang::vfs::FileSystem>)â:
 util/c++/clang.cpp:75:26: error: no matching function for call to âclang::CompilerInstance::setInvocation(clang::CompilerInvocation*)â
   Clang.setInvocation(&*CI);
                           ^
 In file included from util/c++/clang.cpp:14:0:
 /usr/include/clang/Frontend/CompilerInstance.h:231:8: note: candidate: void clang::CompilerInstance::setInvocation(std::shared_ptr<clang::CompilerInvocation>)
    void setInvocation(std::shared_ptr<CompilerInvocation> Value);
         ^~~~~~~~~~~~~

Fixes: 00b86691c77c ("perf clang: Add builtin clang support ant test case")
Signed-off-by: Sandipan Das <sandipan@xxxxxxxxxxxxxxxxxx>
---
 tools/perf/util/c++/clang.cpp | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/c++/clang.cpp b/tools/perf/util/c++/clang.cpp
index 1bfc946e37dc..bf31ceab33bd 100644
--- a/tools/perf/util/c++/clang.cpp
+++ b/tools/perf/util/c++/clang.cpp
@@ -9,6 +9,7 @@
  * Copyright (C) 2016 Huawei Inc.
  */
 
+#include "clang/Basic/Version.h"
 #include "clang/CodeGen/CodeGenAction.h"
 #include "clang/Frontend/CompilerInvocation.h"
 #include "clang/Frontend/CompilerInstance.h"
@@ -58,7 +59,8 @@ createCompilerInvocation(llvm::opt::ArgStringList CFlags, StringRef& Path,
 
 	FrontendOptions& Opts = CI->getFrontendOpts();
 	Opts.Inputs.clear();
-	Opts.Inputs.emplace_back(Path, IK_C);
+	Opts.Inputs.emplace_back(Path,
+			FrontendOptions::getInputKindForExtension("c"));
 	return CI;
 }
 
@@ -71,10 +73,17 @@ getModuleFromSource(llvm::opt::ArgStringList CFlags,
 
 	Clang.setVirtualFileSystem(&*VFS);
 
+#if CLANG_VERSION_MAJOR < 4
 	IntrusiveRefCntPtr<CompilerInvocation> CI =
 		createCompilerInvocation(std::move(CFlags), Path,
 					 Clang.getDiagnostics());
 	Clang.setInvocation(&*CI);
+#else
+	std::shared_ptr<CompilerInvocation> CI(
+		createCompilerInvocation(std::move(CFlags), Path,
+					 Clang.getDiagnostics()));
+	Clang.setInvocation(CI);
+#endif
 
 	std::unique_ptr<CodeGenAction> Act(new EmitLLVMOnlyAction(&*LLVMCtx));
 	if (!Clang.ExecuteAction(*Act))
-- 
2.14.3