From 6b098dee286cc6fe5a5a476464d92dec5602e406 Mon Sep 17 00:00:00 2001
From: Owen Anderson <resistor@mac.com>
Date: Wed, 25 Jun 2008 23:39:39 +0000
Subject: [PATCH] Remember which MachineOperand we were processing, so we don't
 have to scan the list to find it again later. This speeds up live intervals
 from 0.37s to 0.30s on instcombine.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52745 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/CodeGen/LiveIntervalAnalysis.h |  6 ++---
 lib/CodeGen/LiveIntervalAnalysis.cpp        | 26 ++++++++++++---------
 2 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/include/llvm/CodeGen/LiveIntervalAnalysis.h b/include/llvm/CodeGen/LiveIntervalAnalysis.h
index 37acd74ca80..6a2fd9eb707 100644
--- a/include/llvm/CodeGen/LiveIntervalAnalysis.h
+++ b/include/llvm/CodeGen/LiveIntervalAnalysis.h
@@ -328,20 +328,20 @@ namespace llvm {
     /// handleVirtualRegisterDef)
     void handleRegisterDef(MachineBasicBlock *MBB,
                            MachineBasicBlock::iterator MI, unsigned MIIdx,
-                           unsigned reg);
+                           MachineOperand& MO);
 
     /// handleVirtualRegisterDef - update intervals for a virtual
     /// register def
     void handleVirtualRegisterDef(MachineBasicBlock *MBB,
                                   MachineBasicBlock::iterator MI,
-                                  unsigned MIIdx,
+                                  unsigned MIIdx, MachineOperand& MO,
                                   LiveInterval& interval);
 
     /// handlePhysicalRegisterDef - update intervals for a physical register
     /// def.
     void handlePhysicalRegisterDef(MachineBasicBlock* mbb,
                                    MachineBasicBlock::iterator mi,
-                                   unsigned MIIdx,
+                                   unsigned MIIdx, MachineOperand& MO,
                                    LiveInterval &interval,
                                    MachineInstr *CopyMI);
 
diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index 83df4d174a4..ccf7e9d4fd4 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -297,7 +297,7 @@ void LiveIntervals::printRegName(unsigned reg) const {
 
 void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock *mbb,
                                              MachineBasicBlock::iterator mi,
-                                             unsigned MIIdx,
+                                             unsigned MIIdx, MachineOperand& MO,
                                              LiveInterval &interval) {
   DOUT << "\t\tregister: "; DEBUG(printRegName(interval.reg));
   LiveVariables::VarInfo& vi = lv_->getVarInfo(interval.reg);
@@ -428,7 +428,7 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock *mbb,
 
       // If this redefinition is dead, we need to add a dummy unit live
       // range covering the def slot.
-      if (mi->registerDefIsDead(interval.reg, tri_))
+      if (MO.isDead())
         interval.addRange(LiveRange(RedefIndex, RedefIndex+1, OldValNo));
 
       DOUT << " RESULT: ";
@@ -491,6 +491,7 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock *mbb,
 void LiveIntervals::handlePhysicalRegisterDef(MachineBasicBlock *MBB,
                                               MachineBasicBlock::iterator mi,
                                               unsigned MIIdx,
+                                              MachineOperand& MO,
                                               LiveInterval &interval,
                                               MachineInstr *CopyMI) {
   // A physical register cannot be live across basic block, so its
@@ -504,7 +505,7 @@ void LiveIntervals::handlePhysicalRegisterDef(MachineBasicBlock *MBB,
   // If it is not used after definition, it is considered dead at
   // the instruction defining it. Hence its interval is:
   // [defSlot(def), defSlot(def)+1)
-  if (mi->registerDefIsDead(interval.reg, tri_)) {
+  if (MO.isDead()) {
     DOUT << " dead";
     end = getDefIndex(start) + 1;
     goto exit;
@@ -552,23 +553,26 @@ exit:
 void LiveIntervals::handleRegisterDef(MachineBasicBlock *MBB,
                                       MachineBasicBlock::iterator MI,
                                       unsigned MIIdx,
-                                      unsigned reg) {
-  if (TargetRegisterInfo::isVirtualRegister(reg))
-    handleVirtualRegisterDef(MBB, MI, MIIdx, getOrCreateInterval(reg));
-  else if (allocatableRegs_[reg]) {
+                                      MachineOperand& MO) {
+  if (TargetRegisterInfo::isVirtualRegister(MO.getReg()))
+    handleVirtualRegisterDef(MBB, MI, MIIdx, MO, 
+                             getOrCreateInterval(MO.getReg()));
+  else if (allocatableRegs_[MO.getReg()]) {
     MachineInstr *CopyMI = NULL;
     unsigned SrcReg, DstReg;
     if (MI->getOpcode() == TargetInstrInfo::EXTRACT_SUBREG ||
         MI->getOpcode() == TargetInstrInfo::INSERT_SUBREG ||
         tii_->isMoveInstr(*MI, SrcReg, DstReg))
       CopyMI = MI;
-    handlePhysicalRegisterDef(MBB, MI, MIIdx, getOrCreateInterval(reg), CopyMI);
+    handlePhysicalRegisterDef(MBB, MI, MIIdx, MO, 
+                              getOrCreateInterval(MO.getReg()), CopyMI);
     // Def of a register also defines its sub-registers.
-    for (const unsigned* AS = tri_->getSubRegisters(reg); *AS; ++AS)
+    for (const unsigned* AS = tri_->getSubRegisters(MO.getReg()); *AS; ++AS)
       // If MI also modifies the sub-register explicitly, avoid processing it
       // more than once. Do not pass in TRI here so it checks for exact match.
       if (!MI->modifiesRegister(*AS))
-        handlePhysicalRegisterDef(MBB, MI, MIIdx, getOrCreateInterval(*AS), 0);
+        handlePhysicalRegisterDef(MBB, MI, MIIdx, MO, 
+                                  getOrCreateInterval(*AS), 0);
   }
 }
 
@@ -656,7 +660,7 @@ void LiveIntervals::computeIntervals() {
         MachineOperand &MO = MI->getOperand(i);
         // handle register defs - build intervals
         if (MO.isRegister() && MO.getReg() && MO.isDef())
-          handleRegisterDef(MBB, MI, MIIndex, MO.getReg());
+          handleRegisterDef(MBB, MI, MIIndex, MO);
       }
       
       MIIndex += InstrSlots::NUM;