If "optimize for size" attribute is set then block non-trivial loop unswitches but allow trivial loop unswitches.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63670 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/LoopUnswitch.cpp b/lib/Transforms/Scalar/LoopUnswitch.cpp
index a563c7a..436e6a5 100644
--- a/lib/Transforms/Scalar/LoopUnswitch.cpp
+++ b/lib/Transforms/Scalar/LoopUnswitch.cpp
@@ -430,9 +430,6 @@
initLoopData();
Function *F = loopHeader->getParent();
- // Do not unswitch if the function is optimized for size.
- if (!F->isDeclaration() && F->hasFnAttr(Attribute::OptimizeForSize))
- return false;
// Check to see if it would be profitable to unswitch current loop.
unsigned Cost = getLoopUnswitchCost(LoopCond);
@@ -440,6 +437,8 @@
// Do not do non-trivial unswitch while optimizing for size.
if (Cost && OptimizeForSize)
return false;
+ if (Cost && !F->isDeclaration() && F->hasFnAttr(Attribute::OptimizeForSize))
+ return false;
if (Cost > Threshold) {
// FIXME: this should estimate growth by the amount of code shared by the