Add a flag to enable/disable subregister liveness.
llvm-svn: 223884
diff --git a/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp b/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
index 9f7d503..77e7149 100644
--- a/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -63,6 +63,10 @@
static bool EnablePrecomputePhysRegs = false;
#endif // NDEBUG
+static cl::opt<bool> EnableSubRegLiveness(
+ "enable-subreg-liveness", cl::Hidden, cl::init(true),
+ cl::desc("Enable subregister liveness tracking."));
+
void LiveIntervals::getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesCFG();
AU.addRequired<AliasAnalysis>();
@@ -116,6 +120,10 @@
AA = &getAnalysis<AliasAnalysis>();
Indexes = &getAnalysis<SlotIndexes>();
DomTree = &getAnalysis<MachineDominatorTree>();
+
+ if (EnableSubRegLiveness && MF->getSubtarget().enableSubRegLiveness())
+ MRI->enableSubRegLiveness(true);
+
if (!LRCalc)
LRCalc = new LiveRangeCalc();