From: Evan Cheng <evan.cheng@apple.com>
Date: Wed, 27 Aug 2008 20:33:50 +0000 (+0000)
Subject: Refactor isSafeToReMat out of 2addr pass.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=df3b99381f1c211071cc1daf0cc297666877bbcb;p=oota-llvm.git

Refactor isSafeToReMat out of 2addr pass.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55430 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/llvm/CodeGen/MachineInstr.h b/include/llvm/CodeGen/MachineInstr.h
index c9506f198ec..3171af9606e 100644
--- a/include/llvm/CodeGen/MachineInstr.h
+++ b/include/llvm/CodeGen/MachineInstr.h
@@ -250,6 +250,8 @@ public:
   /// the instruction's location and its intended destination.
   bool isSafeToMove(const TargetInstrInfo *TII, bool &SawStore);
 
+  bool isSafeToReMat(const TargetInstrInfo *TII, unsigned DstReg);
+
   //
   // Debugging support
   //
diff --git a/lib/CodeGen/MachineInstr.cpp b/lib/CodeGen/MachineInstr.cpp
index 27e3f663258..966d172bc61 100644
--- a/lib/CodeGen/MachineInstr.cpp
+++ b/lib/CodeGen/MachineInstr.cpp
@@ -711,6 +711,31 @@ bool MachineInstr::isSafeToMove(const TargetInstrInfo *TII, bool &SawStore) {
   return true;
 }
 
+/// isSafeToReMat - Return true if it's safe to rematerialize the specified
+/// instruction which defined the specified register instead of copying it.
+bool MachineInstr::isSafeToReMat(const TargetInstrInfo *TII, unsigned DstReg) {
+  if (!TID->isAsCheapAsAMove())
+    return false;
+  bool SawStore = false;
+  if (!isSafeToMove(TII, SawStore))
+    return false;
+  for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
+    MachineOperand &MO = getOperand(i);
+    if (!MO.isRegister())
+      continue;
+    // FIXME: For now, do not remat any instruction with register operands.
+    // Later on, we can loosen the restriction is the register operands have
+    // not been modified between the def and use. Note, this is different from
+    // MachineSink because the code in no longer in two-address form (at least
+    // partially).
+    if (MO.isUse())
+      return false;
+    else if (!MO.isDead() && MO.getReg() != DstReg)
+      return false;
+  }
+  return true;
+}
+
 void MachineInstr::dump() const {
   cerr << "  " << *this;
 }
diff --git a/lib/CodeGen/TwoAddressInstructionPass.cpp b/lib/CodeGen/TwoAddressInstructionPass.cpp
index 08f576c956f..5093321c6af 100644
--- a/lib/CodeGen/TwoAddressInstructionPass.cpp
+++ b/lib/CodeGen/TwoAddressInstructionPass.cpp
@@ -64,7 +64,6 @@ namespace {
                               unsigned Reg,
                               MachineBasicBlock::iterator OldPos);
 
-    bool isSafeToReMat(unsigned DstReg, MachineInstr *MI);
     bool isProfitableToReMat(unsigned Reg, const TargetRegisterClass *RC,
                              MachineInstr *MI, MachineInstr *DefMI,
                              MachineBasicBlock *MBB, unsigned Loc,
@@ -195,33 +194,6 @@ bool TwoAddressInstructionPass::Sink3AddrInstruction(MachineBasicBlock *MBB,
   return true;
 }
 
-/// isSafeToReMat - Return true if it's safe to rematerialize the specified
-/// instruction which defined the specified register instead of copying it.
-bool
-TwoAddressInstructionPass::isSafeToReMat(unsigned DstReg, MachineInstr *MI) {
-  const TargetInstrDesc &TID = MI->getDesc();
-  if (!TID.isAsCheapAsAMove())
-    return false;
-  bool SawStore = false;
-  if (!MI->isSafeToMove(TII, SawStore))
-    return false;
-  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
-    MachineOperand &MO = MI->getOperand(i);
-    if (!MO.isRegister())
-      continue;
-    // FIXME: For now, do not remat any instruction with register operands.
-    // Later on, we can loosen the restriction is the register operands have
-    // not been modified between the def and use. Note, this is different from
-    // MachineSink because the code in no longer in two-address form (at least
-    // partially).
-    if (MO.isUse())
-      return false;
-    else if (!MO.isDead() && MO.getReg() != DstReg)
-      return false;
-  }
-  return true;
-}
-
 /// isTwoAddrUse - Return true if the specified MI is using the specified
 /// register as a two-address operand.
 static bool isTwoAddrUse(MachineInstr *UseMI, unsigned Reg) {
@@ -431,7 +403,7 @@ bool TwoAddressInstructionPass::runOnMachineFunction(MachineFunction &MF) {
           // If it's safe and profitable, remat the definition instead of
           // copying it.
           if (DefMI &&
-              isSafeToReMat(regB, DefMI) &&
+              DefMI->isSafeToReMat(TII, regB) &&
               isProfitableToReMat(regB, rc, mi, DefMI, mbbi, Dist,DistanceMap)){
             DEBUG(cerr << "2addr: REMATTING : " << *DefMI << "\n");
             TII->reMaterialize(*mbbi, mi, regA, DefMI);