X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FPeepholeOptimizer.cpp;h=a296aea58b7b7328dbd6f2c242be52b8f6fdda8a;hb=8f08516992ec1f5dbe770a966c08a909d4d20c92;hp=d38502298cc50a2134e8dd4824038e63491a3b94;hpb=bd66db27fd6f2a3e1f55c13a4c0ac0d1c8ce6e29;p=oota-llvm.git

diff --git a/lib/CodeGen/PeepholeOptimizer.cpp b/lib/CodeGen/PeepholeOptimizer.cpp
index d38502298cc..a296aea58b7 100644
--- a/lib/CodeGen/PeepholeOptimizer.cpp
+++ b/lib/CodeGen/PeepholeOptimizer.cpp
@@ -107,8 +107,8 @@ STATISTIC(NumRewrittenCopies, "Number of copies rewritten");
 
 namespace {
   class PeepholeOptimizer : public MachineFunctionPass {
-    const TargetMachine   *TM;
     const TargetInstrInfo *TII;
+    const TargetRegisterInfo *TRI;
     MachineRegisterInfo   *MRI;
     MachineDominatorTree  *DT;  // Machine dominator tree
 
@@ -134,6 +134,7 @@ namespace {
     bool optimizeExtInstr(MachineInstr *MI, MachineBasicBlock *MBB,
                           SmallPtrSetImpl<MachineInstr*> &LocalMIs);
     bool optimizeSelect(MachineInstr *MI);
+    bool optimizeCondBranch(MachineInstr *MI);
     bool optimizeCopyOrBitcast(MachineInstr *MI);
     bool optimizeCoalescableCopy(MachineInstr *MI);
     bool optimizeUncoalescableCopy(MachineInstr *MI,
@@ -327,8 +328,7 @@ optimizeExtInstr(MachineInstr *MI, MachineBasicBlock *MBB,
   // Ensure DstReg can get a register class that actually supports
   // sub-registers. Don't change the class until we commit.
   const TargetRegisterClass *DstRC = MRI->getRegClass(DstReg);
-  DstRC = TM->getSubtargetImpl()->getRegisterInfo()->getSubClassWithSubReg(
-      DstRC, SubIdx);
+  DstRC = TRI->getSubClassWithSubReg(DstRC, SubIdx);
   if (!DstRC)
     return false;
 
@@ -338,8 +338,7 @@ optimizeExtInstr(MachineInstr *MI, MachineBasicBlock *MBB,
   // If UseSrcSubIdx is Set, SubIdx also applies to SrcReg, and only uses of
   // SrcReg:SubIdx should be replaced.
   bool UseSrcSubIdx =
-      TM->getSubtargetImpl()->getRegisterInfo()->getSubClassWithSubReg(
-          MRI->getRegClass(SrcReg), SubIdx) != nullptr;
+      TRI->getSubClassWithSubReg(MRI->getRegClass(SrcReg), SubIdx) != nullptr;
 
   // The source has other uses. See if we can replace the other uses with use of
   // the result of the extension.
@@ -499,6 +498,12 @@ bool PeepholeOptimizer::optimizeSelect(MachineInstr *MI) {
   return true;
 }
 
+/// \brief Check if a simpler conditional branch can be
+// generated
+bool PeepholeOptimizer::optimizeCondBranch(MachineInstr *MI) {
+  return TII->optimizeCondBranch(MI);
+}
+
 /// \brief Check if the registers defined by the pair (RegisterClass, SubReg)
 /// share the same register file.
 static bool shareSameRegisterFile(const TargetRegisterInfo &TRI,
@@ -548,7 +553,6 @@ bool PeepholeOptimizer::findNextSource(unsigned &Reg, unsigned &SubReg) {
   unsigned Src;
   unsigned SrcSubReg;
   bool ShouldRewrite = false;
-  const TargetRegisterInfo &TRI = *TM->getSubtargetImpl()->getRegisterInfo();
 
   // Follow the chain of copies until we reach the top of the use-def chain
   // or find a more suitable source.
@@ -571,7 +575,7 @@ bool PeepholeOptimizer::findNextSource(unsigned &Reg, unsigned &SubReg) {
     const TargetRegisterClass *SrcRC = MRI->getRegClass(Src);
 
     // If this source does not incur a cross register bank copy, use it.
-    ShouldRewrite = shareSameRegisterFile(TRI, DefRC, DefSubReg, SrcRC,
+    ShouldRewrite = shareSameRegisterFile(*TRI, DefRC, DefSubReg, SrcRC,
                                           SrcSubReg);
   } while (!ShouldRewrite);
 
@@ -1057,8 +1061,8 @@ bool PeepholeOptimizer::runOnMachineFunction(MachineFunction &MF) {
   if (DisablePeephole)
     return false;
 
-  TM  = &MF.getTarget();
-  TII = TM->getSubtargetImpl()->getInstrInfo();
+  TII = MF.getSubtarget().getInstrInfo();
+  TRI = MF.getSubtarget().getRegisterInfo();
   MRI = &MF.getRegInfo();
   DT  = Aggressive ? &getAnalysis<MachineDominatorTree>() : nullptr;
 
@@ -1105,6 +1109,11 @@ bool PeepholeOptimizer::runOnMachineFunction(MachineFunction &MF) {
         continue;
       }
 
+      if (MI->isConditionalBranch() && optimizeCondBranch(MI)) {
+        Changed = true;
+        continue;
+      }
+
       if (isCoalescableCopy(*MI) && optimizeCoalescableCopy(MI)) {
         // MI is just rewritten.
         Changed = true;