2 files changed, 34 insertions, 14 deletions

diff --git a/llvm/lib/LTO/LTOCodeGenerator.cpp b/llvm/lib/LTO/LTOCodeGenerator.cpp
index 990b578acde..797c64941ef 100644
--- a/llvm/lib/LTO/LTOCodeGenerator.cpp
+++ b/llvm/lib/LTO/LTOCodeGenerator.cpp
@@ -71,7 +71,7 @@ LTOCodeGenerator::LTOCodeGenerator()
 
 LTOCodeGenerator::LTOCodeGenerator(std::unique_ptr<LLVMContext> Context)
     : OwnedContext(std::move(Context)), Context(*OwnedContext),
-      IRLinker(new Module("ld-temp.o", *OwnedContext)) {
+      IRLinker(new Module("ld-temp.o", *OwnedContext)), OptLevel(2) {
   initialize();
 }
 
@@ -291,12 +291,11 @@ const void *LTOCodeGenerator::compileOptimized(size_t *length,
 
 
 bool LTOCodeGenerator::compile_to_file(const char **name,
-                                       bool disableOpt,
                                        bool disableInline,
                                        bool disableGVNLoadPRE,
                                        bool disableVectorization,
                                        std::string &errMsg) {
-  if (!optimize(disableOpt, disableInline, disableGVNLoadPRE,
+  if (!optimize(disableInline, disableGVNLoadPRE,
                 disableVectorization, errMsg))
     return false;
 
@@ -304,12 +303,11 @@ bool LTOCodeGenerator::compile_to_file(const char **name,
 }
 
 const void* LTOCodeGenerator::compile(size_t *length,
-                                      bool disableOpt,
                                       bool disableInline,
                                       bool disableGVNLoadPRE,
                                       bool disableVectorization,
                                       std::string &errMsg) {
-  if (!optimize(disableOpt, disableInline, disableGVNLoadPRE,
+  if (!optimize(disableInline, disableGVNLoadPRE,
                 disableVectorization, errMsg))
     return nullptr;
 
@@ -363,9 +361,25 @@ bool LTOCodeGenerator::determineTarget(std::string &errMsg) {
       MCpu = "cyclone";
   }
 
+  CodeGenOpt::Level CGOptLevel;
+  switch (OptLevel) {
+  case 0:
+    CGOptLevel = CodeGenOpt::None;
+    break;
+  case 1:
+    CGOptLevel = CodeGenOpt::Less;
+    break;
+  case 2:
+    CGOptLevel = CodeGenOpt::Default;
+    break;
+  case 3:
+    CGOptLevel = CodeGenOpt::Aggressive;
+    break;
+  }
+
   TargetMach = march->createTargetMachine(TripleStr, MCpu, FeatureStr, Options,
                                           RelocModel, CodeModel::Default,
-                                          CodeGenOpt::Aggressive);
+                                          CGOptLevel);
   return true;
 }
 
@@ -512,8 +526,7 @@ void LTOCodeGenerator::applyScopeRestrictions() {
 }
 
 /// Optimize merged modules using various IPO passes
-bool LTOCodeGenerator::optimize(bool DisableOpt,
-                                bool DisableInline,
+bool LTOCodeGenerator::optimize(bool DisableInline,
                                 bool DisableGVNLoadPRE,
                                 bool DisableVectorization,
                                 std::string &errMsg) {
@@ -542,8 +555,7 @@ bool LTOCodeGenerator::optimize(bool DisableOpt,
   if (!DisableInline)
     PMB.Inliner = createFunctionInliningPass();
   PMB.LibraryInfo = new TargetLibraryInfoImpl(TargetTriple);
-  if (DisableOpt)
-    PMB.OptLevel = 0;
+  PMB.OptLevel = OptLevel;
   PMB.VerifyInput = true;
   PMB.VerifyOutput = true;
 
diff --git a/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp b/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp
index 8c1e039484b..46e221037ca 100644
--- a/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp
+++ b/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp
@@ -491,10 +491,10 @@ void PassManagerBuilder::addLTOOptimizationPasses(legacy::PassManagerBase &PM) {
   addExtensionsToPM(EP_Peephole, PM);
 
   PM.add(createJumpThreadingPass());
+}
 
-  // Lower bitset metadata to bitsets.
-  PM.add(createLowerBitSetsPass());
-
+void PassManagerBuilder::addLateLTOOptimizationPasses(
+    legacy::PassManagerBase &PM) {
   // Delete basic blocks, which optimization passes may have killed.
   PM.add(createCFGSimplificationPass());
 
@@ -516,9 +516,17 @@ void PassManagerBuilder::populateLTOPassManager(legacy::PassManagerBase &PM) {
     PM.add(createDebugInfoVerifierPass());
   }
 
-  if (OptLevel != 0)
+  if (OptLevel > 1)
     addLTOOptimizationPasses(PM);
 
+  // Lower bit sets to globals. This pass supports Clang's control flow
+  // integrity mechanisms (-fsanitize=cfi*) and needs to run at link time if CFI
+  // is enabled. The pass does nothing if CFI is disabled.
+  PM.add(createLowerBitSetsPass());
+
+  if (OptLevel != 0)
+    addLateLTOOptimizationPasses(PM);
+
   if (VerifyOutput) {
     PM.add(createVerifierPass());
     PM.add(createDebugInfoVerifierPass());