Add a comment for r167040.

[oota-llvm.git] / lib / CodeGen / MachineCopyPropagation.cpp

diff --git a/lib/CodeGen/MachineCopyPropagation.cpp b/lib/CodeGen/MachineCopyPropagation.cpp
index 9730eaacf6e414b627958dad29f4d79d9598e4ed..4a793281b2cd7e8f8cde8b9e89a896a9fc1f3d61 100644 (file)
--- a/lib/CodeGen/MachineCopyPropagation.cpp
+++ b/lib/CodeGen/MachineCopyPropagation.cpp
@@ -16,6 +16,7 @@
 #include "llvm/Pass.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/Target/TargetRegisterInfo.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/ErrorHandling.h"
@@ -32,7 +33,7 @@ STATISTIC(NumDeletes, "Number of dead copies deleted");
 namespace {
   class MachineCopyPropagation : public MachineFunctionPass {
     const TargetRegisterInfo *TRI;
-    BitVector ReservedRegs;
+    MachineRegisterInfo *MRI;
 
   public:
     static char ID; // Pass identification, replacement for typeid
@@ -62,28 +63,16 @@ void
 MachineCopyPropagation::SourceNoLongerAvailable(unsigned Reg,
                               SourceMap &SrcMap,
                               DenseMap<unsigned, MachineInstr*> &AvailCopyMap) {
-  SourceMap::iterator SI = SrcMap.find(Reg);
-  if (SI != SrcMap.end()) {
-    const DestList& Defs = SI->second;
-    for (DestList::const_iterator I = Defs.begin(), E = Defs.end();
-         I != E; ++I) {
-      unsigned MappedDef = *I;
-      // Source of copy is no longer available for propagation.
-      if (AvailCopyMap.erase(MappedDef)) {
-        for (const uint16_t *SR = TRI->getSubRegisters(MappedDef); *SR; ++SR)
-          AvailCopyMap.erase(*SR);
-      }
-    }
-  }
-  for (const uint16_t *AS = TRI->getAliasSet(Reg); *AS; ++AS) {
-    SI = SrcMap.find(*AS);
+  for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI) {
+    SourceMap::iterator SI = SrcMap.find(*AI);
     if (SI != SrcMap.end()) {
       const DestList& Defs = SI->second;
       for (DestList::const_iterator I = Defs.begin(), E = Defs.end();
            I != E; ++I) {
         unsigned MappedDef = *I;
+        // Source of copy is no longer available for propagation.
         if (AvailCopyMap.erase(MappedDef)) {
-          for (const uint16_t *SR = TRI->getSubRegisters(MappedDef); *SR; ++SR)
+          for (MCSubRegIterator SR(MappedDef, TRI); SR.isValid(); ++SR)
             AvailCopyMap.erase(*SR);
         }
       }
@@ -158,8 +147,8 @@ bool MachineCopyPropagation::CopyPropagateBlock(MachineBasicBlock &MBB) {
       DenseMap<unsigned, MachineInstr*>::iterator CI = AvailCopyMap.find(Src);
       if (CI != AvailCopyMap.end()) {
         MachineInstr *CopyMI = CI->second;
-        if (!ReservedRegs.test(Def) &&
-            (!ReservedRegs.test(Src) || NoInterveningSideEffect(CopyMI, MI)) &&
+        if (!MRI->isReserved(Def) &&
+            (!MRI->isReserved(Src) || NoInterveningSideEffect(CopyMI, MI)) &&
             isNopCopy(CopyMI, Def, Src, TRI)) {
           // The two copies cancel out and the source of the first copy
           // hasn't been overridden, eliminate the second one. e.g.
@@ -188,11 +177,8 @@ bool MachineCopyPropagation::CopyPropagateBlock(MachineBasicBlock &MBB) {
       }
 
       // If Src is defined by a previous copy, it cannot be eliminated.
-      CI = CopyMap.find(Src);
-      if (CI != CopyMap.end())
-        MaybeDeadCopies.remove(CI->second);
-      for (const uint16_t *AS = TRI->getAliasSet(Src); *AS; ++AS) {
-        CI = CopyMap.find(*AS);
+      for (MCRegAliasIterator AI(Src, TRI, true); AI.isValid(); ++AI) {
+        CI = CopyMap.find(*AI);
         if (CI != CopyMap.end())
           MaybeDeadCopies.remove(CI->second);
       }
@@ -211,13 +197,13 @@ bool MachineCopyPropagation::CopyPropagateBlock(MachineBasicBlock &MBB) {
 
       // Remember Def is defined by the copy.
       // ... Make sure to clear the def maps of aliases first.
-      for (const uint16_t *AS = TRI->getAliasSet(Def); *AS; ++AS) {
-        CopyMap.erase(*AS);
-        AvailCopyMap.erase(*AS);
+      for (MCRegAliasIterator AI(Def, TRI, false); AI.isValid(); ++AI) {
+        CopyMap.erase(*AI);
+        AvailCopyMap.erase(*AI);
       }
       CopyMap[Def] = MI;
       AvailCopyMap[Def] = MI;
-      for (const uint16_t *SR = TRI->getSubRegisters(Def); *SR; ++SR) {
+      for (MCSubRegIterator SR(Def, TRI); SR.isValid(); ++SR) {
         CopyMap[*SR] = MI;
         AvailCopyMap[*SR] = MI;
       }
@@ -256,11 +242,8 @@ bool MachineCopyPropagation::CopyPropagateBlock(MachineBasicBlock &MBB) {
 
       // If 'Reg' is defined by a copy, the copy is no longer a candidate
       // for elimination.
-      DenseMap<unsigned, MachineInstr*>::iterator CI = CopyMap.find(Reg);
-      if (CI != CopyMap.end())
-        MaybeDeadCopies.remove(CI->second);
-      for (const uint16_t *AS = TRI->getAliasSet(Reg); *AS; ++AS) {
-        CI = CopyMap.find(*AS);
+      for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI) {
+        DenseMap<unsigned, MachineInstr*>::iterator CI = CopyMap.find(*AI);
         if (CI != CopyMap.end())
           MaybeDeadCopies.remove(CI->second);
       }
@@ -277,7 +260,7 @@ bool MachineCopyPropagation::CopyPropagateBlock(MachineBasicBlock &MBB) {
            DI = MaybeDeadCopies.begin(), DE = MaybeDeadCopies.end();
            DI != DE; ++DI) {
         unsigned Reg = (*DI)->getOperand(0).getReg();
-        if (ReservedRegs.test(Reg) || !MaskMO.clobbersPhysReg(Reg))
+        if (MRI->isReserved(Reg) || !MaskMO.clobbersPhysReg(Reg))
           continue;
         (*DI)->eraseFromParent();
         Changed = true;
@@ -296,11 +279,9 @@ bool MachineCopyPropagation::CopyPropagateBlock(MachineBasicBlock &MBB) {
       unsigned Reg = Defs[i];
 
       // No longer defined by a copy.
-      CopyMap.erase(Reg);
-      AvailCopyMap.erase(Reg);
-      for (const uint16_t *AS = TRI->getAliasSet(Reg); *AS; ++AS) {
-        CopyMap.erase(*AS);
-        AvailCopyMap.erase(*AS);
+      for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI) {
+        CopyMap.erase(*AI);
+        AvailCopyMap.erase(*AI);
       }
 
       // If 'Reg' is previously source of a copy, it is no longer available for
@@ -316,7 +297,7 @@ bool MachineCopyPropagation::CopyPropagateBlock(MachineBasicBlock &MBB) {
     for (SmallSetVector<MachineInstr*, 8>::iterator
            DI = MaybeDeadCopies.begin(), DE = MaybeDeadCopies.end();
          DI != DE; ++DI) {
-      if (!ReservedRegs.test((*DI)->getOperand(0).getReg())) {
+      if (!MRI->isReserved((*DI)->getOperand(0).getReg())) {
         (*DI)->eraseFromParent();
         Changed = true;
         ++NumDeletes;
@@ -331,7 +312,7 @@ bool MachineCopyPropagation::runOnMachineFunction(MachineFunction &MF) {
   bool Changed = false;
 
   TRI = MF.getTarget().getRegisterInfo();
-  ReservedRegs = TRI->getReservedRegs(MF);
+  MRI = &MF.getRegInfo();
 
   for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I)
     Changed |= CopyPropagateBlock(*I);