ARM: remove unnecessary state-tracking during frame lowering.

ResolveFrameIndex had what appeared to be a very nasty hack for when the
frame-index referred to a callee-saved register. In this case it "adjusted" the
offset so that the address was correct if (and only if) the MachineInstr
immediately followed the respective push.

This "worked" for all forms of GPR & DPR but was only ever used to set the
frame pointer itself, and once this was put in a more sensible location the
entire state-tracking machinery it relied on became redundant. So I stripped
it.

The only wrinkle is that "add r7, sp, #0" might theoretically be slower (need
an actual ALU slot) compared to "mov r7, sp" so I added a micro-optimisation
that also makes emitARMRegUpdate and emitT2RegUpdate also work when NumBytes ==
0.

No test changes since there shouldn't be any functionality change.

llvm-svn: 194025

1 files changed, 0 insertions, 61 deletions

diff --git a/llvm/lib/Target/ARM/ARMMachineFunctionInfo.h b/llvm/lib/Target/ARM/ARMMachineFunctionInfo.h
index d9ec4fd221a..010edf33cea 100644
--- a/llvm/lib/Target/ARM/ARMMachineFunctionInfo.h
+++ b/llvm/lib/Target/ARM/ARMMachineFunctionInfo.h
@@ -84,12 +84,6 @@ class ARMFunctionInfo : public MachineFunctionInfo {
   unsigned GPRCS2Size;
   unsigned DPRCSSize;
 
-  /// GPRCS1Frames, GPRCS2Frames, DPRCSFrames - Keeps track of frame indices
-  /// which belong to these spill areas.
-  BitVector GPRCS1Frames;
-  BitVector GPRCS2Frames;
-  BitVector DPRCSFrames;
-
   /// NumAlignedDPRCS2Regs - The number of callee-saved DPRs that are saved in
   /// the aligned portion of the stack frame.  This is always a contiguous
   /// sequence of D-registers starting from d8.
@@ -128,7 +122,6 @@ public:
     LRSpilledForFarJump(false),
     FramePtrSpillOffset(0), GPRCS1Offset(0), GPRCS2Offset(0), DPRCSOffset(0),
     GPRCS1Size(0), GPRCS2Size(0), DPRCSSize(0),
-    GPRCS1Frames(0), GPRCS2Frames(0), DPRCSFrames(0),
     NumAlignedDPRCS2Regs(0),
     JumpTableUId(0), PICLabelUId(0),
     VarArgsFrameIndex(0), HasITBlocks(false), GlobalBaseReg(0) {}
@@ -141,7 +134,6 @@ public:
     LRSpilledForFarJump(false),
     FramePtrSpillOffset(0), GPRCS1Offset(0), GPRCS2Offset(0), DPRCSOffset(0),
     GPRCS1Size(0), GPRCS2Size(0), DPRCSSize(0),
-    GPRCS1Frames(32), GPRCS2Frames(32), DPRCSFrames(32),
     JumpTableUId(0), PICLabelUId(0),
     VarArgsFrameIndex(0), HasITBlocks(false), GlobalBaseReg(0) {}
 
@@ -190,59 +182,6 @@ public:
   void setGPRCalleeSavedArea2Size(unsigned s) { GPRCS2Size = s; }
   void setDPRCalleeSavedAreaSize(unsigned s)  { DPRCSSize = s; }
 
-  bool isGPRCalleeSavedArea1Frame(int fi) const {
-    if (fi < 0 || fi >= (int)GPRCS1Frames.size())
-      return false;
-    return GPRCS1Frames[fi];
-  }
-  bool isGPRCalleeSavedArea2Frame(int fi) const {
-    if (fi < 0 || fi >= (int)GPRCS2Frames.size())
-      return false;
-    return GPRCS2Frames[fi];
-  }
-  bool isDPRCalleeSavedAreaFrame(int fi) const {
-    if (fi < 0 || fi >= (int)DPRCSFrames.size())
-      return false;
-    return DPRCSFrames[fi];
-  }
-
-  void addGPRCalleeSavedArea1Frame(int fi) {
-    if (fi >= 0) {
-      int Size = GPRCS1Frames.size();
-      if (fi >= Size) {
-        Size *= 2;
-        if (fi >= Size)
-          Size = fi+1;
-        GPRCS1Frames.resize(Size);
-      }
-      GPRCS1Frames[fi] = true;
-    }
-  }
-  void addGPRCalleeSavedArea2Frame(int fi) {
-    if (fi >= 0) {
-      int Size = GPRCS2Frames.size();
-      if (fi >= Size) {
-        Size *= 2;
-        if (fi >= Size)
-          Size = fi+1;
-        GPRCS2Frames.resize(Size);
-      }
-      GPRCS2Frames[fi] = true;
-    }
-  }
-  void addDPRCalleeSavedAreaFrame(int fi) {
-    if (fi >= 0) {
-      int Size = DPRCSFrames.size();
-      if (fi >= Size) {
-        Size *= 2;
-        if (fi >= Size)
-          Size = fi+1;
-        DPRCSFrames.resize(Size);
-      }
-      DPRCSFrames[fi] = true;
-    }
-  }
-
   unsigned createJumpTableUId() {
     return JumpTableUId++;
   }