PPCFrameLowering's FramePointerOffset can be computed at initialization

time. Do so.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228998 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/PowerPC/PPCFrameLowering.cpp

@@ -47,11 +47,25 @@ static unsigned computeTOCSaveOffset(const PPCSubtarget &STI) {
   return STI.isELFv2ABI() ? 24 : 40;
 }
 
+static unsigned computeFramePointerSaveOffset(const PPCSubtarget &STI) {
+  // For the Darwin ABI:
+  // We cannot use the TOC save slot (offset +20) in the PowerPC linkage area
+  // for saving the frame pointer (if needed.)  While the published ABI has
+  // not used this slot since at least MacOSX 10.2, there is older code
+  // around that does use it, and that needs to continue to work.
+  if (STI.isDarwinABI())
+    return STI.isPPC64() ? -8U : -4U;
+
+  // SVR4 ABI: First slot in the general register save area.
+  return STI.isPPC64() ? -8U : -4U;
+}
+
 PPCFrameLowering::PPCFrameLowering(const PPCSubtarget &STI)
     : TargetFrameLowering(TargetFrameLowering::StackGrowsDown,
                           (STI.hasQPX() || STI.isBGQ()) ? 32 : 16, 0),
       Subtarget(STI), ReturnSaveOffset(computeReturnSaveOffset(Subtarget)),
-      TOCSaveOffset(computeTOCSaveOffset(Subtarget)) {}
+      TOCSaveOffset(computeTOCSaveOffset(Subtarget)),
+      FramePointerSaveOffset(computeFramePointerSaveOffset(Subtarget)) {}
 
 // With the SVR4 ABI, callee-saved registers have fixed offsets on the stack.
 const PPCFrameLowering::SpillSlot *PPCFrameLowering::getCalleeSavedSpillSlots(
@@ -620,8 +634,7 @@ void PPCFrameLowering::emitPrologue(MachineFunction &MF) const {
       assert(FPIndex && "No Frame Pointer Save Slot!");
       FPOffset = FFI->getObjectOffset(FPIndex);
     } else {
-      FPOffset =
+      FPOffset = getFramePointerSaveOffset();
-          PPCFrameLowering::getFramePointerSaveOffset(isPPC64, isDarwinABI);
     }
   }
 
@@ -958,8 +971,7 @@ void PPCFrameLowering::emitEpilogue(MachineFunction &MF,
       assert(FPIndex && "No Frame Pointer Save Slot!");
       FPOffset = FFI->getObjectOffset(FPIndex);
     } else {
-      FPOffset =
+      FPOffset = getFramePointerSaveOffset();
-          PPCFrameLowering::getFramePointerSaveOffset(isPPC64, isDarwinABI);
     }
   }
 
@@ -1159,7 +1171,7 @@ PPCFrameLowering::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
   // If the frame pointer save index hasn't been defined yet.
   if (!FPSI && needsFP(MF)) {
     // Find out what the fix offset of the frame pointer save area.
-    int FPOffset = getFramePointerSaveOffset(isPPC64, isDarwinABI);
+    int FPOffset = getFramePointerSaveOffset();
     // Allocate the frame index for frame pointer save area.
     FPSI = MFI->CreateFixedObject(isPPC64? 8 : 4, FPOffset, true);
     // Save the result.

lib/Target/PowerPC/PPCFrameLowering.h

@@ -25,6 +25,7 @@ class PPCFrameLowering: public TargetFrameLowering {
   const PPCSubtarget &Subtarget;
   const unsigned ReturnSaveOffset;
   const unsigned TOCSaveOffset;
+  const unsigned FramePointerSaveOffset;
 
 public:
   PPCFrameLowering(const PPCSubtarget &STI);
@@ -77,18 +78,7 @@ public:
 
   /// getFramePointerSaveOffset - Return the previous frame offset to save the
   /// frame pointer.
-  static unsigned getFramePointerSaveOffset(bool isPPC64, bool isDarwinABI) {
+  unsigned getFramePointerSaveOffset() const { return FramePointerSaveOffset; }
-    // For the Darwin ABI:
-    // We cannot use the TOC save slot (offset +20) in the PowerPC linkage area
-    // for saving the frame pointer (if needed.)  While the published ABI has
-    // not used this slot since at least MacOSX 10.2, there is older code
-    // around that does use it, and that needs to continue to work.
-    if (isDarwinABI)
-      return isPPC64 ? -8U : -4U;
-
-    // SVR4 ABI: First slot in the general register save area.
-    return isPPC64 ? -8U : -4U;
-  }
 
   /// getBasePointerSaveOffset - Return the previous frame offset to save the
   /// base pointer.

lib/Target/PowerPC/PPCISelLowering.cpp

@@ -3472,10 +3472,9 @@ static SDValue EmitTailCallStoreFPAndRetAddr(SelectionDAG &DAG,
   if (SPDiff) {
     // Calculate the new stack slot for the return address.
     int SlotSize = isPPC64 ? 8 : 4;
-    int NewRetAddrLoc = SPDiff +
+    const PPCFrameLowering *FL =
-                        MF.getSubtarget<PPCSubtarget>()
+        MF.getSubtarget<PPCSubtarget>().getFrameLowering();
-                            .getFrameLowering()
+    int NewRetAddrLoc = SPDiff + FL->getReturnSaveOffset();
-                            ->getReturnSaveOffset();
     int NewRetAddr = MF.getFrameInfo()->CreateFixedObject(SlotSize,
                                                           NewRetAddrLoc, true);
     EVT VT = isPPC64 ? MVT::i64 : MVT::i32;
@@ -3487,8 +3486,7 @@ static SDValue EmitTailCallStoreFPAndRetAddr(SelectionDAG &DAG,
     // When using the 32/64-bit SVR4 ABI there is no need to move the FP stack
     // slot as the FP is never overwritten.
     if (isDarwinABI) {
-      int NewFPLoc =
+      int NewFPLoc = SPDiff + FL->getFramePointerSaveOffset();
-        SPDiff + PPCFrameLowering::getFramePointerSaveOffset(isPPC64, isDarwinABI);
       int NewFPIdx = MF.getFrameInfo()->CreateFixedObject(SlotSize, NewFPLoc,
                                                           true);
       SDValue NewFramePtrIdx = DAG.getFrameIndex(NewFPIdx, VT);
@@ -5332,7 +5330,6 @@ SDValue
 PPCTargetLowering::getFramePointerFrameIndex(SelectionDAG & DAG) const {
   MachineFunction &MF = DAG.getMachineFunction();
   bool isPPC64 = Subtarget.isPPC64();
-  bool isDarwinABI = Subtarget.isDarwinABI();
   EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy();
 
   // Get current frame pointer save index.  The users of this index will be
@@ -5343,9 +5340,7 @@ PPCTargetLowering::getFramePointerFrameIndex(SelectionDAG & DAG) const {
   // If the frame pointer save index hasn't been defined yet.
   if (!FPSI) {
     // Find out what the fix offset of the frame pointer save area.
-    int FPOffset = PPCFrameLowering::getFramePointerSaveOffset(isPPC64,
+    int FPOffset = Subtarget.getFrameLowering()->getFramePointerSaveOffset();
-                                                           isDarwinABI);
-
     // Allocate the frame index for frame pointer save area.
     FPSI = MF.getFrameInfo()->CreateFixedObject(isPPC64? 8 : 4, FPOffset, true);
     // Save the result.