[Reproducers] lldb-instr: tool to generate instrumentation macros.

This patch introduces a new tool called 'lldb-instr'. It automates the
workflow of inserting LLDB_RECORD and LLDB_REGSITER macros for
instrumentation.

Because the tool won't be part of the build process, I didn't want to
over-complicate it. SB_RECORD macros are inserted in place, while
SB_REGISTER macros are printed to stdout, and have to be manually copied
into the Registry's constructor. Additionally, the utility makes no
attempt to properly format the inserted macros. Please use clang-format
to format the changes after running the tool.

Differential revision: https://reviews.llvm.org/D56822

llvm-svn: 353271

lldb/lit/Reproducer/Inputs/foo.cpp

@@ -0,0 +1,18 @@
+struct Foo {
+  Foo();
+  Foo(int i);
+
+  void A();
+  void B(int i);
+  int C(int i);
+  int D(bool b) const;
+  static void E();
+  static int F(int i);
+};
+
+void Foo::A() {}
+void Foo::B(int i) {}
+int Foo::C(int i) { return i; }
+int Foo::D(bool b) const { return 1; }
+void Foo::E() {}
+int Foo::F(int i) { return i; }

lldb/lit/Reproducer/TestInstrumentationRecord.test

@@ -0,0 +1,10 @@
+# RUN: cp %p/Inputs/foo.cpp %t.cpp
+# RUN: lldb-instr %t.cpp
+# RUN: cat %t.cpp | FileCheck %s
+
+# CHECK: LLDB_RECORD_METHOD_NO_ARGS(void, Foo, A);
+# CHECK: LLDB_RECORD_METHOD(void, Foo, B, (int), i);
+# CHECK: LLDB_RECORD_METHOD(int, Foo, C, (int), i);
+# CHECK: LLDB_RECORD_METHOD_CONST(int, Foo, D, (bool), b);
+# CHECK: LLDB_RECORD_STATIC_METHOD_NO_ARGS(void, Foo, E);
+# CHECK: LLDB_RECORD_STATIC_METHOD(int, Foo, F, (int), i);

lldb/lit/Reproducer/TestInstrumentationRegister.test

@@ -0,0 +1,9 @@
+# RUN: cp %p/Inputs/foo.cpp %t.cpp
+# RUN: lldb-instr %t.cpp | FileCheck %s
+
+# CHECK: LLDB_REGISTER_METHOD(void, Foo, A, ());
+# CHECK: LLDB_REGISTER_METHOD(void, Foo, B, (int));
+# CHECK: LLDB_REGISTER_METHOD(int, Foo, C, (int));
+# CHECK: LLDB_REGISTER_METHOD_CONST(int, Foo, D, (bool));
+# CHECK: LLDB_REGISTER_STATIC_METHOD(void, Foo, E, ());
+# CHECK: LLDB_REGISTER_STATIC_METHOD(int, Foo, F, (int));

lldb/lit/helper/toolchain.py

@@ -24,7 +24,7 @@ def use_lldb_substitutions(config):
 
     build_script = os.path.dirname(__file__)
     build_script = os.path.join(build_script, 'build.py')
-    build_script_args = [build_script, 
+    build_script_args = [build_script,
                         '--compiler=any', # Default to best compiler
                         '--arch=' + str(config.lldb_bitness)]
     if config.lldb_lit_tools_dir:
@@ -44,6 +44,7 @@ def use_lldb_substitutions(config):
                   extra_args=dsargs,
                   unresolved='ignore'),
         'lldb-test',
+        'lldb-instr',
         ToolSubst('%build',
                   command="'" + sys.executable + "'",
                   extra_args=build_script_args)

lldb/tools/CMakeLists.txt

@@ -1,6 +1,7 @@
 add_subdirectory(argdumper)
 add_subdirectory(driver)
 add_subdirectory(intel-features)
+add_subdirectory(lldb-instr)
 add_subdirectory(lldb-mi)
 add_subdirectory(lldb-test)
 add_subdirectory(lldb-vscode)

lldb/tools/lldb-instr/CMakeLists.txt

@@ -0,0 +1,12 @@
+add_lldb_tool(lldb-instr
+  Instrument.cpp
+
+  LINK_LIBS
+    clangAST
+    clangBasic
+    clangFrontend
+    clangTooling
+
+  LINK_COMPONENTS
+    Support
+  )

lldb/tools/lldb-instr/Instrument.cpp

@@ -0,0 +1,285 @@
+#include "clang/AST/AST.h"
+#include "clang/AST/ASTConsumer.h"
+#include "clang/AST/RecursiveASTVisitor.h"
+#include "clang/Frontend/ASTConsumers.h"
+#include "clang/Frontend/CompilerInstance.h"
+#include "clang/Frontend/FrontendActions.h"
+#include "clang/Rewrite/Core/Rewriter.h"
+#include "clang/Tooling/CommonOptionsParser.h"
+#include "clang/Tooling/Tooling.h"
+
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/raw_ostream.h"
+
+#include <sstream>
+#include <string>
+
+using namespace clang;
+using namespace clang::driver;
+using namespace clang::tooling;
+
+static llvm::cl::OptionCategory InstrCategory("LLDB Instrumentation Generator");
+
+/// Get the macro name for recording method calls.
+///
+/// LLDB_RECORD_METHOD
+/// LLDB_RECORD_METHOD_CONST
+/// LLDB_RECORD_METHOD_NO_ARGS
+/// LLDB_RECORD_METHOD_CONST_NO_ARGS
+/// LLDB_RECORD_STATIC_METHOD
+/// LLDB_RECORD_STATIC_METHOD_NO_ARGS
+static std::string GetRecordMethodMacroName(bool Static, bool Const,
+                                            bool NoArgs) {
+  std::string Macro;
+  llvm::raw_string_ostream OS(Macro);
+
+  OS << "LLDB_RECORD";
+  if (Static)
+    OS << "_STATIC";
+  OS << "_METHOD";
+  if (Const)
+    OS << "_CONST";
+  if (NoArgs)
+    OS << "_NO_ARGS";
+
+  return OS.str();
+}
+
+/// Get the macro name for register methods.
+///
+/// LLDB_REGISTER_CONSTRUCTOR
+/// LLDB_REGISTER_METHOD
+/// LLDB_REGISTER_METHOD_CONST
+/// LLDB_REGISTER_STATIC_METHOD
+static std::string GetRegisterMethodMacroName(bool Static, bool Const) {
+  std::string Macro;
+  llvm::raw_string_ostream OS(Macro);
+
+  OS << "LLDB_REGISTER";
+  if (Static)
+    OS << "_STATIC";
+  OS << "_METHOD";
+  if (Const)
+    OS << "_CONST";
+
+  return OS.str();
+}
+
+static std::string GetRecordMethodMacro(StringRef Result, StringRef Class,
+                                        StringRef Method, StringRef Signature,
+                                        StringRef Values, bool Static,
+                                        bool Const) {
+  std::string Macro;
+  llvm::raw_string_ostream OS(Macro);
+
+  OS << GetRecordMethodMacroName(Static, Const, Values.empty());
+  OS << "(" << Result << ", " << Class << ", " << Method;
+
+  if (!Values.empty()) {
+    OS << ", (" << Signature << "), " << Values << ");\n\n";
+  } else {
+    OS << ");\n\n";
+  }
+
+  return OS.str();
+}
+
+static std::string GetRecordConstructorMacro(StringRef Class,
+                                             StringRef Signature,
+                                             StringRef Values) {
+  std::string Macro;
+  llvm::raw_string_ostream OS(Macro);
+  if (!Values.empty()) {
+    OS << "LLDB_RECORD_CONSTRUCTOR(" << Class << ", (" << Signature << "), "
+       << Values << ");\n\n";
+  } else {
+    OS << "LLDB_RECORD_CONSTRUCTOR_NO_ARGS(" << Class << ");\n\n";
+  }
+  return OS.str();
+}
+
+static std::string GetRegisterConstructorMacro(StringRef Class,
+                                               StringRef Signature) {
+  std::string Macro;
+  llvm::raw_string_ostream OS(Macro);
+  OS << "LLDB_REGISTER_CONSTRUCTOR(" << Class << ", (" << Signature
+     << "));\n\n";
+  return OS.str();
+}
+
+static std::string GetRegisterMethodMacro(StringRef Result, StringRef Class,
+                                          StringRef Method, StringRef Signature,
+                                          bool Static, bool Const) {
+  std::string Macro;
+  llvm::raw_string_ostream OS(Macro);
+  OS << GetRegisterMethodMacroName(Static, Const);
+  OS << "(" << Result << ", " << Class << ", " << Method << ", (" << Signature
+     << "));\n";
+  return OS.str();
+}
+
+class SBVisitor : public RecursiveASTVisitor<SBVisitor> {
+public:
+  SBVisitor(Rewriter &R, ASTContext &Context)
+      : MyRewriter(R), Context(Context) {}
+
+  bool VisitCXXMethodDecl(CXXMethodDecl *Decl) {
+    // Not all decls should be registered. Please refer to that method's
+    // comment for details.
+    if (ShouldSkip(Decl))
+      return false;
+
+    // Print 'bool' instead of '_Bool'.
+    PrintingPolicy Policy(Context.getLangOpts());
+    Policy.Bool = true;
+
+    // Collect the functions parameter types and names.
+    std::vector<std::string> ParamTypes;
+    std::vector<std::string> ParamNames;
+    for (auto *P : Decl->parameters()) {
+      QualType T = P->getType();
+
+      // Currently we don't support functions that have function pointers as an
+      // argument.
+      if (T->isFunctionPointerType())
+        return false;
+
+      // Currently we don't support functions that have void pointers as an
+      // argument.
+      if (T->isVoidPointerType())
+        return false;
+
+      ParamTypes.push_back(T.getAsString(Policy));
+      ParamNames.push_back(P->getNameAsString());
+    }
+
+    // Convert the two lists to string for the macros.
+    std::string ParamTypesStr = llvm::join(ParamTypes, ", ");
+    std::string ParamNamesStr = llvm::join(ParamNames, ", ");
+
+    CXXRecordDecl *Record = Decl->getParent();
+    QualType ReturnType = Decl->getReturnType();
+
+    // Construct the macros.
+    std::string Macro;
+    if (isa<CXXConstructorDecl>(Decl)) {
+      llvm::outs() << GetRegisterConstructorMacro(Record->getNameAsString(),
+                                                  ParamTypesStr);
+
+      Macro = GetRecordConstructorMacro(Record->getNameAsString(),
+                                        ParamTypesStr, ParamNamesStr);
+    } else {
+      llvm::outs() << GetRegisterMethodMacro(
+          ReturnType.getAsString(Policy), Record->getNameAsString(),
+          Decl->getNameAsString(), ParamTypesStr, Decl->isStatic(),
+          Decl->isConst());
+
+      Macro = GetRecordMethodMacro(
+          ReturnType.getAsString(Policy), Record->getNameAsString(),
+          Decl->getNameAsString(), ParamTypesStr, ParamNamesStr,
+          Decl->isStatic(), Decl->isConst());
+    }
+
+    // If this CXXMethodDecl already starts with a macro we're done.
+    Stmt *Body = Decl->getBody();
+    for (auto &C : Body->children()) {
+      if (C->getBeginLoc().isMacroID())
+        return false;
+      break;
+    }
+
+    // Insert the macro at the beginning of the function. We don't attempt to
+    // fix the formatting and instead rely on clang-format to fix it after the
+    // tool has run. This is also the reason that the macros end with two
+    // newlines, counting on clang-format to normalize this in case the macro
+    // got inserted before an existing newline.
+    SourceLocation InsertLoc = Lexer::getLocForEndOfToken(
+        Body->getBeginLoc(), 0, MyRewriter.getSourceMgr(),
+        MyRewriter.getLangOpts());
+    MyRewriter.InsertTextAfter(InsertLoc, Macro);
+
+    return true;
+  }
+
+private:
+  /// Determine whether we need to consider the given CXXMethodDecl.
+  ///
+  /// Currently we skip the following cases:
+  ///  1. Decls outside the main source file,
+  ///  2. Decls that are only present in the source file,
+  ///  3. Decls that are not definitions,
+  ///  4. Non-public decls,
+  ///  5. Destructors.
+  bool ShouldSkip(CXXMethodDecl *Decl) {
+    // Skip anything outside the main file.
+    if (!MyRewriter.getSourceMgr().isInMainFile(Decl->getBeginLoc()))
+      return true;
+
+    // Skip if the canonical decl in the current decl. It means that the method
+    // is declared in the implementation and is therefore not exposed as part
+    // of the API.
+    if (Decl == Decl->getCanonicalDecl())
+      return true;
+
+    // Skip decls that have no body, i.e. are just declarations.
+    Stmt *Body = Decl->getBody();
+    if (!Body)
+      return true;
+
+    // Skip non-public decls.
+    AccessSpecifier AS = Decl->getAccess();
+    if (AS != AccessSpecifier::AS_public)
+      return true;
+
+    // Skip destructors.
+    if (isa<CXXDestructorDecl>(Decl))
+      return true;
+
+    return false;
+  }
+
+  Rewriter &MyRewriter;
+  ASTContext &Context;
+};
+
+class SBConsumer : public ASTConsumer {
+public:
+  SBConsumer(Rewriter &R, ASTContext &Context) : Visitor(R, Context) {}
+
+  // Override the method that gets called for each parsed top-level
+  // declaration.
+  bool HandleTopLevelDecl(DeclGroupRef DR) override {
+    for (DeclGroupRef::iterator b = DR.begin(), e = DR.end(); b != e; ++b) {
+      Visitor.TraverseDecl(*b);
+    }
+    return true;
+  }
+
+private:
+  SBVisitor Visitor;
+};
+
+class SBAction : public ASTFrontendAction {
+public:
+  SBAction() = default;
+
+  void EndSourceFileAction() override { MyRewriter.overwriteChangedFiles(); }
+
+  std::unique_ptr<ASTConsumer> CreateASTConsumer(CompilerInstance &CI,
+                                                 StringRef file) override {
+    MyRewriter.setSourceMgr(CI.getSourceManager(), CI.getLangOpts());
+    return llvm::make_unique<SBConsumer>(MyRewriter, CI.getASTContext());
+  }
+
+private:
+  Rewriter MyRewriter;
+};
+
+int main(int argc, const char **argv) {
+  CommonOptionsParser OP(argc, argv, InstrCategory,
+                         "Utility for generating the macros for LLDB's "
+                         "instrumentation framework.");
+  ClangTool T(OP.getCompilations(), OP.getSourcePathList());
+  return T.run(newFrontendActionFactory<SBAction>().get());
+}