Make globalopt refine global variable alignment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100160 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/IPO/GlobalOpt.cpp b/lib/Transforms/IPO/GlobalOpt.cpp
index ddff5ef..c09e78e 100644
--- a/lib/Transforms/IPO/GlobalOpt.cpp
+++ b/lib/Transforms/IPO/GlobalOpt.cpp
@@ -1880,6 +1880,7 @@
bool GlobalOpt::OptimizeGlobalVars(Module &M) {
bool Changed = false;
+ TargetData *TD = getAnalysisIfAvailable<TargetData>();
for (Module::global_iterator GVI = M.global_begin(), E = M.global_end();
GVI != E; ) {
GlobalVariable *GV = GVI++;
@@ -1889,11 +1890,16 @@
// Simplify the initializer.
if (GV->hasInitializer())
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(GV->getInitializer())) {
- TargetData *TD = getAnalysisIfAvailable<TargetData>();
Constant *New = ConstantFoldConstantExpression(CE, TD);
if (New && New != CE)
GV->setInitializer(New);
}
+ // Refine the alignment value.
+ if (TD && GV->hasDefinitiveInitializer()) {
+ unsigned Align = TD->getPreferredAlignment(GV);
+ if (Align > GV->getAlignment())
+ GV->setAlignment(Align);
+ }
// Do more involved optimizations if the global is internal.
if (!GV->isConstant() && GV->hasLocalLinkage() &&
GV->hasInitializer())