make asan work at -O0, llvm part. Patch by glider@google.com

llvm-svn: 145530

llvm/include/llvm/Transforms/IPO/PassManagerBuilder.h

@@ -67,7 +67,12 @@ public:
     /// EP_ScalarOptimizerLate - This extension point allows adding optimization
     /// passes after most of the main optimizations, but before the last
     /// cleanup-ish optimizations.
-    EP_ScalarOptimizerLate
+    EP_ScalarOptimizerLate,
+
+    /// EP_EnabledOnOptLevel0 - This extension point allows adding passes that
+    /// should not be disabled by O0 optimization level. The passes will be
+    /// inserted after the inlining pass.
+    EP_EnabledOnOptLevel0
   };
 
   /// The Optimization Level - Specify the basic optimization level.

llvm/lib/Transforms/IPO/PassManagerBuilder.cpp

@@ -101,6 +101,7 @@ void PassManagerBuilder::populateModulePassManager(PassManagerBase &MPM) {
       MPM.add(Inliner);
       Inliner = 0;
     }
+    addExtensionsToPM(EP_EnabledOnOptLevel0, MPM);
     return;
   }
 
@@ -340,4 +341,3 @@ void LLVMPassManagerBuilderPopulateLTOPassManager(LLVMPassManagerBuilderRef PMB,
   PassManagerBase *LPM = unwrap(PM);
   Builder->populateLTOPassManager(*LPM, Internalize, RunInliner);
 }
-