Driver: begin threading frontend support for SymbolRewriter

Allow blessed access to the symbol rewriter from the driver. Although the
symbol rewriter could be invoked through tools like opt and llc, it would not
accessible from the frontend. This allows us to read the rewrite map files in
the frontend rather than the backend and enable symbol rewriting for actually
performing the symbol interpositioning.

llvm-svn: 225504

6 files changed, 60 insertions, 0 deletions

diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index 3c1dd218316..48e29839afe 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -577,6 +577,13 @@ def frewrite_includes : Flag<["-"], "frewrite-includes">, Group<f_Group>,
   Flags<[CC1Option]>;
 def fno_rewrite_includes : Flag<["-"], "fno-rewrite-includes">, Group<f_Group>;
 
+def frewrite_map_file : Separate<["-"], "frewrite-map-file">,
+                        Group<f_Group>,
+                        Flags<[ DriverOption, CC1Option ]>;
+def frewrite_map_file_EQ : Joined<["-"], "frewrite-map-file=">,
+                           Group<f_Group>,
+                           Flags<[DriverOption]>;
+
 def ffreestanding : Flag<["-"], "ffreestanding">, Group<f_Group>, Flags<[CC1Option]>,
   HelpText<"Assert that the compilation takes place in a freestanding environment">;
 def fgnu_keywords : Flag<["-"], "fgnu-keywords">, Group<f_Group>, Flags<[CC1Option]>,
diff --git a/clang/include/clang/Frontend/CodeGenOptions.h b/clang/include/clang/Frontend/CodeGenOptions.h
index 4e6171fbfe9..19cc6c11c5a 100644
--- a/clang/include/clang/Frontend/CodeGenOptions.h
+++ b/clang/include/clang/Frontend/CodeGenOptions.h
@@ -176,6 +176,9 @@ public:
   /// flag.
   std::shared_ptr<llvm::Regex> OptimizationRemarkAnalysisPattern;
 
+  /// Set of files definining the rules for the symbol rewriting.
+  std::vector<std::string> RewriteMapFiles;
+
 public:
   // Define accessors/mutators for code generation options of enumeration type.
 #define CODEGENOPT(Name, Bits, Default)
diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
index 54215743f8a..e1267192a74 100644
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -39,6 +39,7 @@
 #include "llvm/Transforms/Instrumentation.h"
 #include "llvm/Transforms/ObjCARC.h"
 #include "llvm/Transforms/Scalar.h"
+#include "llvm/Transforms/Utils/SymbolRewriter.h"
 #include <memory>
 using namespace clang;
 using namespace llvm;
@@ -234,6 +235,17 @@ static TargetLibraryInfo *createTLI(llvm::Triple &TargetTriple,
   return TLI;
 }
 
+static void addSymbolRewriterPass(const CodeGenOptions &Opts,
+                                  PassManager *MPM) {
+  llvm::SymbolRewriter::RewriteDescriptorList DL;
+
+  llvm::SymbolRewriter::RewriteMapParser MapParser;
+  for (const auto &MapFile : Opts.RewriteMapFiles)
+    MapParser.parse(MapFile, &DL);
+
+  MPM->add(createRewriteSymbolsPass(DL));
+}
+
 void EmitAssemblyHelper::CreatePasses() {
   unsigned OptLevel = CodeGenOpts.OptimizationLevel;
   CodeGenOptions::InliningMethod Inlining = CodeGenOpts.getInlining();
@@ -346,6 +358,8 @@ void EmitAssemblyHelper::CreatePasses() {
 
   // Set up the per-module pass manager.
   PassManager *MPM = getPerModulePasses();
+  if (!CodeGenOpts.RewriteMapFiles.empty())
+    addSymbolRewriterPass(CodeGenOpts, MPM);
   if (CodeGenOpts.VerifyModule)
     MPM->add(createDebugInfoVerifierPass());
 
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index ef744d03b1a..d625c0e3e2f 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -2781,6 +2781,19 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
 
   // LLVM Code Generator Options.
 
+  if (Args.hasArg(options::OPT_frewrite_map_file) ||
+      Args.hasArg(options::OPT_frewrite_map_file_EQ)) {
+    for (arg_iterator
+             MFI = Args.filtered_begin(options::OPT_frewrite_map_file,
+                                       options::OPT_frewrite_map_file_EQ),
+             MFE = Args.filtered_end();
+         MFI != MFE; ++MFI) {
+      CmdArgs.push_back("-frewrite-map-file");
+      CmdArgs.push_back((*MFI)->getValue());
+      (*MFI)->claim();
+    }
+  }
+
   if (Arg *A = Args.getLastArg(options::OPT_Wframe_larger_than_EQ)) {
     StringRef v = A->getValue();
     CmdArgs.push_back("-mllvm");
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 5b344284139..d630b5bf5c4 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -594,6 +594,8 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
   if (NeedLocTracking && Opts.getDebugInfo() == CodeGenOptions::NoDebugInfo)
     Opts.setDebugInfo(CodeGenOptions::LocTrackingOnly);
 
+  Opts.RewriteMapFiles = Args.getAllArgValues(OPT_frewrite_map_file);
+
   return Success;
 }
 
diff --git a/clang/test/Driver/symbol-rewriter.c b/clang/test/Driver/symbol-rewriter.c
new file mode 100644
index 00000000000..3cfdb9d09cd
--- /dev/null
+++ b/clang/test/Driver/symbol-rewriter.c
@@ -0,0 +1,21 @@
+// RUN: %clang -frewrite-map-file %S/Inputs/rewrite.map -### %s 2>&1 | FileCheck %s -check-prefix CHECK-SINGLE
+
+// CHECK-SINGLE: "-frewrite-map-file" "{{.*[\\/]}}rewrite.map"
+
+// RUN: %clang -frewrite-map-file %S/Inputs/rewrite-1.map -frewrite-map-file %S/Inputs/rewrite-2.map -### %s 2>&1 | FileCheck %s -check-prefix CHECK-MULTIPLE
+
+// CHECK-MULTIPLE: "-frewrite-map-file" "{{.*[\\/]}}rewrite-1.map" "-frewrite-map-file" "{{.*[\\/]}}rewrite-2.map"
+
+// RUN: %clang -frewrite-map-file=%S/Inputs/rewrite.map -### %s 2>&1 | FileCheck %s -check-prefix CHECK-SINGLE-EQ
+
+// CHECK-SINGLE-EQ: "-frewrite-map-file" "{{.*[\\/]}}rewrite.map"
+
+// RUN: %clang -frewrite-map-file=%S/Inputs/rewrite-1.map -frewrite-map-file=%S/Inputs/rewrite-2.map -### %s 2>&1 | FileCheck %s -check-prefix CHECK-MULTIPLE-EQ
+
+// CHECK-MULTIPLE-EQ: "-frewrite-map-file" "{{.*[\\/]}}rewrite-1.map"
+// CHECK-MULTIPLE-EQ: "-frewrite-map-file" "{{.*[\\/]}}rewrite-2.map"
+
+// RUN: %clang -frewrite-map-file %S/Inputs/rewrite-1.map -frewrite-map-file=%S/Inputs/rewrite-2.map -### %s 2>&1 | FileCheck %s -check-prefix CHECK-MIXED
+
+// CHECK-MIXED: "-frewrite-map-file" "{{.*[\\/]}}rewrite-1.map" "-frewrite-map-file" "{{.*[\\/]}}rewrite-2.map"
+