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-rw-r--r--lib/Transforms/IPO/GlobalOpt.cpp18
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;
}