Thumb2 assembly parsing and encoding for USAX.

[oota-llvm.git] / lib / Target / Mips / MipsFrameLowering.cpp

diff --git a/lib/Target/Mips/MipsFrameLowering.cpp b/lib/Target/Mips/MipsFrameLowering.cpp
index 41ad18783aceb1b10907ff0e1c71d4dfd289d17e..22d1e47b1a2b6699c166c8da8c560affdc19f75e 100644 (file)
--- a/lib/Target/Mips/MipsFrameLowering.cpp
+++ b/lib/Target/Mips/MipsFrameLowering.cpp
@@ -84,7 +84,8 @@ using namespace llvm;
 // if frame pointer elimination is disabled.
 bool MipsFrameLowering::hasFP(const MachineFunction &MF) const {
   const MachineFrameInfo *MFI = MF.getFrameInfo();
-  return DisableFramePointerElim(MF) || MFI->hasVarSizedObjects();
+  return DisableFramePointerElim(MF) || MFI->hasVarSizedObjects()
+      || MFI->isFrameAddressTaken();
 }
 
 bool MipsFrameLowering::targetHandlesStackFrameRounding() const {
@@ -172,6 +173,10 @@ void MipsFrameLowering::emitPrologue(MachineFunction &MF) const {
   // No need to allocate space on the stack.
   if (StackSize == 0 && !MFI->adjustsStack()) return;
 
+  MachineModuleInfo &MMI = MF.getMMI();
+  std::vector<MachineMove> &Moves = MMI.getFrameMoves();
+  MachineLocation DstML, SrcML;
+
   // Adjust stack : addi sp, sp, (-imm)
   ATUsed = expandRegLargeImmPair(Mips::SP, -StackSize, NewReg, NewImm, MBB,
                                  MBBI);
@@ -182,24 +187,82 @@ void MipsFrameLowering::emitPrologue(MachineFunction &MF) const {
   if (ATUsed)
     BuildMI(MBB, MBBI, dl, TII.get(Mips::ATMACRO));
 
-  // if framepointer enabled, set it to point to the stack pointer.
-  if (hasFP(MF)) {
+  // emit ".cfi_def_cfa_offset StackSize"
+  MCSymbol *AdjustSPLabel = MMI.getContext().CreateTempSymbol();
+  BuildMI(MBB, MBBI, dl,
+          TII.get(TargetOpcode::PROLOG_LABEL)).addSym(AdjustSPLabel);
+  DstML = MachineLocation(MachineLocation::VirtualFP);
+  SrcML = MachineLocation(MachineLocation::VirtualFP, -StackSize);
+  Moves.push_back(MachineMove(AdjustSPLabel, DstML, SrcML));
+
+  const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo();
+
+  if (CSI.size()) {
     // Find the instruction past the last instruction that saves a callee-saved
     // register to the stack.
-    const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo();
-  
     for (unsigned i = 0; i < CSI.size(); ++i)
       ++MBBI;
  
+    // Iterate over list of callee-saved registers and emit .cfi_offset
+    // directives.
+    MCSymbol *CSLabel = MMI.getContext().CreateTempSymbol();
+    BuildMI(MBB, MBBI, dl,
+            TII.get(TargetOpcode::PROLOG_LABEL)).addSym(CSLabel);
+ 
+    for (std::vector<CalleeSavedInfo>::const_iterator I = CSI.begin(),
+           E = CSI.end(); I != E; ++I) {
+      int64_t Offset = MFI->getObjectOffset(I->getFrameIdx());
+      unsigned Reg = I->getReg();
+
+      // If Reg is a double precision register, emit two cfa_offsets,
+      // one for each of the paired single precision registers.
+      if (Mips::AFGR64RegisterClass->contains(Reg)) {
+        const unsigned *SubRegs = RegInfo->getSubRegisters(Reg);
+        MachineLocation DstML0(MachineLocation::VirtualFP, Offset);
+        MachineLocation DstML1(MachineLocation::VirtualFP, Offset + 4);
+        MachineLocation SrcML0(*SubRegs);
+        MachineLocation SrcML1(*(SubRegs + 1));
+
+        if (!STI.isLittle())
+          std::swap(SrcML0, SrcML1);
+
+        Moves.push_back(MachineMove(CSLabel, DstML0, SrcML0));
+        Moves.push_back(MachineMove(CSLabel, DstML1, SrcML1));
+      }
+      else {
+        // Reg is either in CPURegs or FGR32.
+        DstML = MachineLocation(MachineLocation::VirtualFP, Offset);
+        SrcML = MachineLocation(Reg);
+        Moves.push_back(MachineMove(CSLabel, DstML, SrcML));
+      }
+    }
+  }    
+
+  // if framepointer enabled, set it to point to the stack pointer.
+  if (hasFP(MF)) {
     // Insert instruction "move $fp, $sp" at this location.    
     BuildMI(MBB, MBBI, dl, TII.get(Mips::ADDu), Mips::FP)
       .addReg(Mips::SP).addReg(Mips::ZERO);
+
+    // emit ".cfi_def_cfa_register $fp" 
+    MCSymbol *SetFPLabel = MMI.getContext().CreateTempSymbol();
+    BuildMI(MBB, MBBI, dl,
+            TII.get(TargetOpcode::PROLOG_LABEL)).addSym(SetFPLabel);
+    DstML = MachineLocation(Mips::FP);
+    SrcML = MachineLocation(MachineLocation::VirtualFP);
+    Moves.push_back(MachineMove(SetFPLabel, DstML, SrcML));
   }
 
   // Restore GP from the saved stack location
-  if (MipsFI->needGPSaveRestore())
-    BuildMI(MBB, MBBI, dl, TII.get(Mips::CPRESTORE))
-      .addImm(MFI->getObjectOffset(MipsFI->getGPFI()));
+  if (MipsFI->needGPSaveRestore()) {
+    unsigned Offset = MFI->getObjectOffset(MipsFI->getGPFI());
+    BuildMI(MBB, MBBI, dl, TII.get(Mips::CPRESTORE)).addImm(Offset);
+
+    if (Offset >= 0x8000) {
+      BuildMI(MBB, llvm::prior(MBBI), dl, TII.get(Mips::MACRO));
+      BuildMI(MBB, MBBI, dl, TII.get(Mips::NOMACRO));
+    }
+  }
 }
 
 void MipsFrameLowering::emitEpilogue(MachineFunction &MF,
@@ -247,7 +310,6 @@ void MipsFrameLowering::
 processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
                                      RegScavenger *RS) const {
   MachineRegisterInfo& MRI = MF.getRegInfo();
-  MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
 
   // FIXME: remove this code if register allocator can correctly mark
   //        $fp and $ra used or unused.
@@ -261,7 +323,7 @@ processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
   // instructions to save/restore $ra unless there is a function call.
   // To correct this, $ra is explicitly marked unused if there is no
   // function call.
-  if (MipsFI->hasCall())
+  if (MF.getFrameInfo()->hasCalls())
     MRI.setPhysRegUsed(Mips::RA);
   else
     MRI.setPhysRegUnused(Mips::RA);