diff options
Diffstat (limited to 'lib/Transforms/IPO/GlobalOpt.cpp')
-rw-r--r-- | lib/Transforms/IPO/GlobalOpt.cpp | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/lib/Transforms/IPO/GlobalOpt.cpp b/lib/Transforms/IPO/GlobalOpt.cpp index 36c04f092b..dc9b2a8105 100644 --- a/lib/Transforms/IPO/GlobalOpt.cpp +++ b/lib/Transforms/IPO/GlobalOpt.cpp @@ -17,6 +17,7 @@ #include "llvm/ADT/DenseMap.h" #include "llvm/ADT/STLExtras.h" #include "llvm/ADT/SmallPtrSet.h" +#include "llvm/ADT/SmallSet.h" #include "llvm/ADT/SmallVector.h" #include "llvm/ADT/Statistic.h" #include "llvm/Analysis/ConstantFolding.h" @@ -1699,9 +1700,6 @@ static bool TryToShrinkGlobalToBoolean(GlobalVariable *GV, Constant *OtherVal) { /// possible. If we make a change, return true. bool GlobalOpt::ProcessGlobal(GlobalVariable *GV, Module::global_iterator &GVI) { - if (!GV->isDiscardableIfUnused()) - return false; - // Do more involved optimizations if the global is internal. GV->removeDeadConstantUsers(); @@ -1944,6 +1942,13 @@ bool GlobalOpt::OptimizeFunctions(Module &M) { bool GlobalOpt::OptimizeGlobalVars(Module &M) { bool Changed = false; + + SmallSet<const Comdat *, 8> NotDiscardableComdats; + for (const GlobalVariable &GV : M.globals()) + if (const Comdat *C = GV.getComdat()) + if (!GV.isDiscardableIfUnused()) + NotDiscardableComdats.insert(C); + for (Module::global_iterator GVI = M.global_begin(), E = M.global_end(); GVI != E; ) { GlobalVariable *GV = GVI++; @@ -1958,7 +1963,12 @@ bool GlobalOpt::OptimizeGlobalVars(Module &M) { GV->setInitializer(New); } - Changed |= ProcessGlobal(GV, GVI); + if (GV->isDiscardableIfUnused()) { + if (const Comdat *C = GV->getComdat()) + if (NotDiscardableComdats.count(C)) + continue; + Changed |= ProcessGlobal(GV, GVI); + } } return Changed; } |