[asan] don't emit __asan_mapping_offset/__asan_mapping_scale by default -- they are currently used only for experiments
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153040 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 544e22c..a51bd7e 100644
--- a/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -579,18 +579,23 @@
if (ClGlobals)
Res |= insertGlobalRedzones(M);
- // Tell the run-time the current values of mapping offset and scale.
- GlobalValue *asan_mapping_offset =
- new GlobalVariable(M, IntptrTy, true, GlobalValue::LinkOnceODRLinkage,
- ConstantInt::get(IntptrTy, MappingOffset),
- kAsanMappingOffsetName);
- GlobalValue *asan_mapping_scale =
- new GlobalVariable(M, IntptrTy, true, GlobalValue::LinkOnceODRLinkage,
- ConstantInt::get(IntptrTy, MappingScale),
- kAsanMappingScaleName);
- // Read these globals, otherwise they may be optimized away.
- IRB.CreateLoad(asan_mapping_scale, true);
- IRB.CreateLoad(asan_mapping_offset, true);
+ if (ClMappingOffsetLog >= 0) {
+ // Tell the run-time the current values of mapping offset and scale.
+ GlobalValue *asan_mapping_offset =
+ new GlobalVariable(M, IntptrTy, true, GlobalValue::LinkOnceODRLinkage,
+ ConstantInt::get(IntptrTy, MappingOffset),
+ kAsanMappingOffsetName);
+ // Read the global, otherwise it may be optimized away.
+ IRB.CreateLoad(asan_mapping_offset, true);
+ }
+ if (ClMappingScale) {
+ GlobalValue *asan_mapping_scale =
+ new GlobalVariable(M, IntptrTy, true, GlobalValue::LinkOnceODRLinkage,
+ ConstantInt::get(IntptrTy, MappingScale),
+ kAsanMappingScaleName);
+ // Read the global, otherwise it may be optimized away.
+ IRB.CreateLoad(asan_mapping_scale, true);
+ }
for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F) {