Support for instrumenting only selected files or functions

This change implements support for applying profile instrumentation
only to selected files or functions. The implementation uses the
sanitizer special case list format to select which files and functions
to instrument, and relies on the new noprofile IR attribute to exclude
functions from instrumentation.

Differential Revision: https://reviews.llvm.org/D94820

1 files changed, 113 insertions, 0 deletions

diff --git a/clang/lib/Basic/ProfileList.cpp b/clang/lib/Basic/ProfileList.cpp
new file mode 100644
index 000000000000..56bc37a79301
--- /dev/null
+++ b/clang/lib/Basic/ProfileList.cpp
@@ -0,0 +1,113 @@
+//===--- ProfileList.h - ProfileList filter ---------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+//
+// User-provided filters include/exclude profile instrumentation in certain
+// functions or files.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Basic/ProfileList.h"
+#include "clang/Basic/FileManager.h"
+#include "clang/Basic/SourceManager.h"
+#include "llvm/Support/SpecialCaseList.h"
+
+#include "llvm/Support/raw_ostream.h"
+
+using namespace clang;
+
+namespace clang {
+
+class ProfileSpecialCaseList : public llvm::SpecialCaseList {
+public:
+  static std::unique_ptr<ProfileSpecialCaseList>
+  create(const std::vector<std::string> &Paths, llvm::vfs::FileSystem &VFS,
+         std::string &Error);
+
+  static std::unique_ptr<ProfileSpecialCaseList>
+  createOrDie(const std::vector<std::string> &Paths,
+              llvm::vfs::FileSystem &VFS);
+
+  bool isEmpty() const { return Sections.empty(); }
+
+  bool hasPrefix(StringRef Prefix) const {
+    for (auto &SectionIter : Sections)
+      if (SectionIter.Entries.count(Prefix) > 0)
+        return true;
+    return false;
+  }
+};
+
+std::unique_ptr<ProfileSpecialCaseList>
+ProfileSpecialCaseList::create(const std::vector<std::string> &Paths,
+                               llvm::vfs::FileSystem &VFS,
+                               std::string &Error) {
+  auto PSCL = std::make_unique<ProfileSpecialCaseList>();
+  if (PSCL->createInternal(Paths, VFS, Error))
+    return PSCL;
+  return nullptr;
+}
+
+std::unique_ptr<ProfileSpecialCaseList>
+ProfileSpecialCaseList::createOrDie(const std::vector<std::string> &Paths,
+                                    llvm::vfs::FileSystem &VFS) {
+  std::string Error;
+  if (auto PSCL = create(Paths, VFS, Error))
+    return PSCL;
+  llvm::report_fatal_error(Error);
+}
+
+}
+
+ProfileList::ProfileList(ArrayRef<std::string> Paths, SourceManager &SM)
+    : SCL(ProfileSpecialCaseList::createOrDie(
+          Paths, SM.getFileManager().getVirtualFileSystem())),
+      Empty(SCL->isEmpty()),
+      Default(SCL->hasPrefix("fun") || SCL->hasPrefix("src")), SM(SM) {}
+
+ProfileList::~ProfileList() = default;
+
+static StringRef getSectionName(CodeGenOptions::ProfileInstrKind Kind) {
+  switch (Kind) {
+  case CodeGenOptions::ProfileNone:
+    return "";
+  case CodeGenOptions::ProfileClangInstr:
+    return "clang";
+  case CodeGenOptions::ProfileIRInstr:
+    return "llvm";
+  case CodeGenOptions::ProfileCSIRInstr:
+    return "csllvm";
+  }
+}
+
+llvm::Optional<bool>
+ProfileList::isFunctionExcluded(StringRef FunctionName,
+                                CodeGenOptions::ProfileInstrKind Kind) const {
+  StringRef Section = getSectionName(Kind);
+  if (SCL->inSection(Section, "!fun", FunctionName))
+    return true;
+  if (SCL->inSection(Section, "fun", FunctionName))
+    return false;
+  return None;
+}
+
+llvm::Optional<bool>
+ProfileList::isLocationExcluded(SourceLocation Loc,
+                                CodeGenOptions::ProfileInstrKind Kind) const {
+  return isFileExcluded(SM.getFilename(SM.getFileLoc(Loc)), Kind);
+}
+
+llvm::Optional<bool>
+ProfileList::isFileExcluded(StringRef FileName,
+                            CodeGenOptions::ProfileInstrKind Kind) const {
+  StringRef Section = getSectionName(Kind);
+  if (SCL->inSection(Section, "!src", FileName))
+    return true;
+  if (SCL->inSection(Section, "src", FileName))
+    return false;
+  return None;
+}