X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FExecutionDepsFix.cpp;h=cbc3b80a6a5c130fae602ffda97aa0e18f0c1d89;hb=896f064a4900458e3fb245ad3f6fc9e7a3d8c8cd;hp=4793fba76069b6a22b64f113ac8e66867ed5f872;hpb=ae6bbac7332f6d541ecf8f1317db69b8768f7e74;p=oota-llvm.git

diff --git a/lib/CodeGen/ExecutionDepsFix.cpp b/lib/CodeGen/ExecutionDepsFix.cpp
index 4793fba7606..cbc3b80a6a5 100644
--- a/lib/CodeGen/ExecutionDepsFix.cpp
+++ b/lib/CodeGen/ExecutionDepsFix.cpp
@@ -113,7 +113,7 @@ struct DomainValue {
 }
 
 namespace {
-/// LiveReg - Information about a live register.
+/// Information about a live register.
 struct LiveReg {
   /// Value currently in this register, or NULL when no value is being tracked.
   /// This counts as a DomainValue reference.
@@ -125,7 +125,7 @@ struct LiveReg {
   /// will be a negative number.
   int Def;
 };
-} // anonynous namespace
+} // anonymous namespace
 
 namespace {
 class ExeDepsFix : public MachineFunctionPass {
@@ -225,7 +225,7 @@ DomainValue *ExeDepsFix::alloc(int domain) {
   return dv;
 }
 
-/// release - Release a reference to DV.  When the last reference is released,
+/// Release a reference to DV.  When the last reference is released,
 /// collapse if needed.
 void ExeDepsFix::release(DomainValue *DV) {
   while (DV) {
@@ -245,8 +245,8 @@ void ExeDepsFix::release(DomainValue *DV) {
   }
 }
 
-/// resolve - Follow the chain of dead DomainValues until a live DomainValue is
-/// reached.  Update the referenced pointer when necessary.
+/// Follow the chain of dead DomainValues until a live DomainValue is reached.
+/// Update the referenced pointer when necessary.
 DomainValue *ExeDepsFix::resolve(DomainValue *&DVRef) {
   DomainValue *DV = DVRef;
   if (!DV || !DV->Next)
@@ -325,8 +325,7 @@ void ExeDepsFix::collapse(DomainValue *dv, unsigned domain) {
         setLiveReg(rx, alloc(domain));
 }
 
-/// Merge - All instructions and registers in B are moved to A, and B is
-/// released.
+/// All instructions and registers in B are moved to A, and B is released.
 bool ExeDepsFix::merge(DomainValue *A, DomainValue *B) {
   assert(!A->isCollapsed() && "Cannot merge into collapsed");
   assert(!B->isCollapsed() && "Cannot merge from collapsed");
@@ -352,7 +351,7 @@ bool ExeDepsFix::merge(DomainValue *A, DomainValue *B) {
   return true;
 }
 
-// enterBasicBlock - Set up LiveRegs by merging predecessor live-out values.
+/// Set up LiveRegs by merging predecessor live-out values.
 void ExeDepsFix::enterBasicBlock(MachineBasicBlock *MBB) {
   // Detect back-edges from predecessors we haven't processed yet.
   SeenUnknownBackEdge = false;
@@ -560,12 +559,11 @@ void ExeDepsFix::processUndefReads(MachineBasicBlock *MBB) {
   MachineInstr *UndefMI = UndefReads.back().first;
   unsigned OpIdx = UndefReads.back().second;
 
-  for (MachineBasicBlock::reverse_iterator I = MBB->rbegin(), E = MBB->rend();
-       I != E; ++I) {
+  for (MachineInstr &I : make_range(MBB->rbegin(), MBB->rend())) {
     // Update liveness, including the current instruction's defs.
-    LiveRegSet.stepBackward(*I);
+    LiveRegSet.stepBackward(I);
 
-    if (UndefMI == &*I) {
+    if (UndefMI == &I) {
       if (!LiveRegSet.contains(UndefMI->getOperand(OpIdx).getReg()))
         TII->breakPartialRegDependency(UndefMI, OpIdx, TRI);
 
@@ -734,12 +732,14 @@ bool ExeDepsFix::runOnMachineFunction(MachineFunction &mf) {
   // If no relevant registers are used in the function, we can skip it
   // completely.
   bool anyregs = false;
+  const MachineRegisterInfo &MRI = mf.getRegInfo();
   for (TargetRegisterClass::const_iterator I = RC->begin(), E = RC->end();
-       I != E; ++I)
-    if (MF->getRegInfo().isPhysRegUsed(*I)) {
-      anyregs = true;
-      break;
-    }
+       I != E && !anyregs; ++I)
+    for (MCRegAliasIterator AI(*I, TRI, true); AI.isValid(); ++AI)
+      if (!MRI.reg_nodbg_empty(*AI)) {
+        anyregs = true;
+        break;
+      }
   if (!anyregs) return false;
 
   // Initialize the AliasMap on the first use.