SimplifyCFG: Don't duplicate calls to functions marked noduplicate v2
v2:
- Use CI->cannotDuplicate()
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193115 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp
index 0833286..1398697 100644
--- a/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -1561,6 +1561,19 @@
return true;
}
+/// \returns True if this block contains a CallInst with the NoDuplicate
+/// attribute.
+static bool HasNoDuplicateCall(const BasicBlock *BB) {
+ for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E; ++I) {
+ const CallInst *CI = dyn_cast<CallInst>(I);
+ if (!CI)
+ continue;
+ if (CI->cannotDuplicate())
+ return true;
+ }
+ return false;
+}
+
/// BlockIsSimpleEnoughToThreadThrough - Return true if we can thread a branch
/// across this block.
static bool BlockIsSimpleEnoughToThreadThrough(BasicBlock *BB) {
@@ -1608,6 +1621,8 @@
// Now we know that this block has multiple preds and two succs.
if (!BlockIsSimpleEnoughToThreadThrough(BB)) return false;
+ if (HasNoDuplicateCall(BB)) return false;
+
// Okay, this is a simple enough basic block. See if any phi values are
// constants.
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {