1 files changed, 27 insertions, 16 deletions

diff --git a/lib/CodeGen/PeepholeOptimizer.cpp b/lib/CodeGen/PeepholeOptimizer.cpp
index 6bc7e37e3d..096df7bf6a 100644
--- a/lib/CodeGen/PeepholeOptimizer.cpp
+++ b/lib/CodeGen/PeepholeOptimizer.cpp
@@ -79,6 +79,7 @@ STATISTIC(NumBitcasts,   "Number of bitcasts eliminated");
 STATISTIC(NumCmps,       "Number of compares eliminated");
 STATISTIC(NumImmFold,    "Number of move immediate folded");
 STATISTIC(NumLoadFold,   "Number of loads folded");
+STATISTIC(NumSelects,    "Number of selects optimized");
 
 namespace {
   class PeepholeOptimizer : public MachineFunctionPass {
@@ -109,6 +110,7 @@ namespace {
     bool optimizeCmpInstr(MachineInstr *MI, MachineBasicBlock *MBB);
     bool optimizeExtInstr(MachineInstr *MI, MachineBasicBlock *MBB,
                           SmallPtrSet<MachineInstr*, 8> &LocalMIs);
+    bool optimizeSelect(MachineInstr *MI);
     bool isMoveImmediate(MachineInstr *MI,
                          SmallSet<unsigned, 4> &ImmDefRegs,
                          DenseMap<unsigned, MachineInstr*> &ImmDefMIs);
@@ -386,6 +388,23 @@ bool PeepholeOptimizer::optimizeCmpInstr(MachineInstr *MI,
   return false;
 }
 
+/// Optimize a select instruction.
+bool PeepholeOptimizer::optimizeSelect(MachineInstr *MI) {
+  unsigned TrueOp = 0;
+  unsigned FalseOp = 0;
+  bool Optimizable = false;
+  SmallVector<MachineOperand, 4> Cond;
+  if (TII->analyzeSelect(MI, Cond, TrueOp, FalseOp, Optimizable))
+    return false;
+  if (!Optimizable)
+    return false;
+  if (!TII->optimizeSelect(MI))
+    return false;
+  MI->eraseFromParent();
+  ++NumSelects;
+  return true;
+}
+
 /// isLoadFoldable - Check whether MI is a candidate for folding into a later
 /// instruction. We only fold loads to virtual registers and the virtual
 /// register defined has a single use.
@@ -496,22 +515,14 @@ bool PeepholeOptimizer::runOnMachineFunction(MachineFunction &MF) {
       if (MI->mayStore() || MI->isCall())
         FoldAsLoadDefReg = 0;
 
-      if (MI->isBitcast()) {
-        if (optimizeBitcastInstr(MI, MBB)) {
-          // MI is deleted.
-          LocalMIs.erase(MI);
-          Changed = true;
-          MII = First ? I->begin() : llvm::next(PMII);
-          continue;
-        }
-      } else if (MI->isCompare()) {
-        if (optimizeCmpInstr(MI, MBB)) {
-          // MI is deleted.
-          LocalMIs.erase(MI);
-          Changed = true;
-          MII = First ? I->begin() : llvm::next(PMII);
-          continue;
-        }
+      if ((MI->isBitcast() && optimizeBitcastInstr(MI, MBB)) ||
+          (MI->isCompare() && optimizeCmpInstr(MI, MBB)) ||
+          (MI->isSelect() && optimizeSelect(MI))) {
+        // MI is deleted.
+        LocalMIs.erase(MI);
+        Changed = true;
+        MII = First ? I->begin() : llvm::next(PMII);
+        continue;
       }
 
       if (isMoveImmediate(MI, ImmDefRegs, ImmDefMIs)) {