4 files changed, 27 insertions, 20 deletions
diff --git a/lib/Target/PowerPC/PPCFrameLowering.cpp b/lib/Target/PowerPC/PPCFrameLowering.cpp
index cc1ed6967b..6dfb4c8d77 100644
--- a/lib/Target/PowerPC/PPCFrameLowering.cpp
+++ b/lib/Target/PowerPC/PPCFrameLowering.cpp
@@ -786,7 +786,8 @@ PPCFrameLowering::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
   PPCFunctionInfo *FI = MF.getInfo<PPCFunctionInfo>();
   unsigned LR = RegInfo->getRARegister();
   FI->setMustSaveLR(MustSaveLR(MF, LR));
-  MF.getRegInfo().setPhysRegUnused(LR);
+  MachineRegisterInfo &MRI = MF.getRegInfo();
+  MRI.setPhysRegUnused(LR);
 
   //  Save R31 if necessary
   int FPSI = FI->getFramePointerSaveIndex();
@@ -811,6 +812,16 @@ PPCFrameLowering::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
     MFI->CreateFixedObject(-1 * TCSPDelta, TCSPDelta, true);
   }
 
+  // For 32-bit SVR4, allocate the nonvolatile CR spill slot iff the 
+  // function uses CR 2, 3, or 4.
+  if (!isPPC64 && !isDarwinABI && 
+      (MRI.isPhysRegUsed(PPC::CR2) ||
+       MRI.isPhysRegUsed(PPC::CR3) ||
+       MRI.isPhysRegUsed(PPC::CR4))) {
+    int FrameIdx = MFI->CreateFixedObject((uint64_t)4, (int64_t)-4, true);
+    FI->setCRSpillFrameIndex(FrameIdx);
+  }
+
   // Reserve a slot closest to SP or frame pointer if we have a dynalloc or
   // a large stack, which will require scavenging a register to materialize a
   // large offset.
diff --git a/lib/Target/PowerPC/PPCMachineFunctionInfo.h b/lib/Target/PowerPC/PPCMachineFunctionInfo.h
index 24caffa3f0..045b375dd8 100644
--- a/lib/Target/PowerPC/PPCMachineFunctionInfo.h
+++ b/lib/Target/PowerPC/PPCMachineFunctionInfo.h
@@ -71,6 +71,9 @@ class PPCFunctionInfo : public MachineFunctionInfo {
   /// register for parameter passing.
   unsigned VarArgsNumFPR;
 
+  /// CRSpillFrameIndex - FrameIndex for CR spill slot for 32-bit SVR4.
+  int CRSpillFrameIndex;
+
 public:
   explicit PPCFunctionInfo(MachineFunction &MF) 
     : FramePointerSaveIndex(0),
@@ -83,7 +86,8 @@ public:
       VarArgsFrameIndex(0),
       VarArgsStackOffset(0),
       VarArgsNumGPR(0),
-      VarArgsNumFPR(0) {}
+      VarArgsNumFPR(0),
+      CRSpillFrameIndex(0) {}
 
   int getFramePointerSaveIndex() const { return FramePointerSaveIndex; }
   void setFramePointerSaveIndex(int Idx) { FramePointerSaveIndex = Idx; }
@@ -125,6 +129,9 @@ public:
 
   unsigned getVarArgsNumFPR() const { return VarArgsNumFPR; }
   void setVarArgsNumFPR(unsigned Num) { VarArgsNumFPR = Num; }
+
+  int getCRSpillFrameIndex() const { return CRSpillFrameIndex; }
+  void setCRSpillFrameIndex(int idx) { CRSpillFrameIndex = idx; }
 };
 
 } // end of namespace llvm
diff --git a/lib/Target/PowerPC/PPCRegisterInfo.cpp b/lib/Target/PowerPC/PPCRegisterInfo.cpp
index 9745235525..df245cc655 100644
--- a/lib/Target/PowerPC/PPCRegisterInfo.cpp
+++ b/lib/Target/PowerPC/PPCRegisterInfo.cpp
@@ -71,7 +71,7 @@ PPCRegisterInfo::PPCRegisterInfo(const PPCSubtarget &ST,
   : PPCGenRegisterInfo(ST.isPPC64() ? PPC::LR8 : PPC::LR,
                        ST.isPPC64() ? 0 : 1,
                        ST.isPPC64() ? 0 : 1),
-    Subtarget(ST), TII(tii), CRSpillFrameIdx(0) {
+    Subtarget(ST), TII(tii) {
   ImmToIdxMap[PPC::LD]   = PPC::LDX;    ImmToIdxMap[PPC::STD]  = PPC::STDX;
   ImmToIdxMap[PPC::LBZ]  = PPC::LBZX;   ImmToIdxMap[PPC::STB]  = PPC::STBX;
   ImmToIdxMap[PPC::LHZ]  = PPC::LHZX;   ImmToIdxMap[PPC::LHA]  = PPC::LHAX;
@@ -111,11 +111,6 @@ PPCRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
     return Subtarget.isPPC64() ? CSR_Darwin64_SaveList :
                                  CSR_Darwin32_SaveList;
 
-  // For 32-bit SVR4, also initialize the frame index associated with
-  // the CR spill slot.
-  if (!Subtarget.isPPC64())
-    CRSpillFrameIdx = 0;
-
   return Subtarget.isPPC64() ? CSR_SVR464_SaveList : CSR_SVR432_SaveList;
 }
 
@@ -450,19 +445,14 @@ PPCRegisterInfo::hasReservedSpillSlot(const MachineFunction &MF,
   // For the nonvolatile condition registers (CR2, CR3, CR4) in an SVR4
   // ABI, return true to prevent allocating an additional frame slot.
   // For 64-bit, the CR save area is at SP+8; the value of FrameIdx = 0
-  // is arbitrary and will be subsequently ignored.  For 32-bit, we must
-  // create exactly one stack slot and return its FrameIdx for all
-  // nonvolatiles.
+  // is arbitrary and will be subsequently ignored.  For 32-bit, we have
+  // previously created the stack slot if needed, so return its FrameIdx.
   if (Subtarget.isSVR4ABI() && PPC::CR2 <= Reg && Reg <= PPC::CR4) {
-    if (Subtarget.isPPC64()) {
+    if (Subtarget.isPPC64())
       FrameIdx = 0;
-    } else if (CRSpillFrameIdx) {
-      FrameIdx = CRSpillFrameIdx;
-    } else {
-      MachineFrameInfo *MFI = 
-        (const_cast<MachineFunction &>(MF)).getFrameInfo();
-      FrameIdx = MFI->CreateFixedObject((uint64_t)4, (int64_t)-4, true);
-      CRSpillFrameIdx = FrameIdx;
+    else {
+      const PPCFunctionInfo *FI = MF.getInfo<PPCFunctionInfo>();
+      FrameIdx = FI->getCRSpillFrameIndex();
     }
     return true;
   }
diff --git a/lib/Target/PowerPC/PPCRegisterInfo.h b/lib/Target/PowerPC/PPCRegisterInfo.h
index c22450eb58..9840666242 100644
--- a/lib/Target/PowerPC/PPCRegisterInfo.h
+++ b/lib/Target/PowerPC/PPCRegisterInfo.h
@@ -30,7 +30,6 @@ class PPCRegisterInfo : public PPCGenRegisterInfo {
   std::map<unsigned, unsigned> ImmToIdxMap;
   const PPCSubtarget &Subtarget;
   const TargetInstrInfo &TII;
-  mutable int CRSpillFrameIdx;
 public:
   PPCRegisterInfo(const PPCSubtarget &SubTarget, const TargetInstrInfo &tii);