Implement frame unwinding information emission for Thumb1. Not finished yet because there is no way given the constpool index to examine the actual entry: the reason is clones inserted by constant island pass, which are not tracked at all! The only connection is done during asmprinting time via magic label names which is really gross and needs to be eventually fixed.

llvm-svn: 127104

llvm/lib/Target/ARM/ARMAsmPrinter.cpp

@@ -822,11 +822,15 @@ void ARMAsmPrinter::EmitUnwindingInstruction(const MachineInstr *MI) {
   unsigned Opc = MI->getOpcode();
   unsigned SrcReg, DstReg;
 
-  // Special case: tPUSH does not have src/dst regs.
+  if (Opc == ARM::tPUSH || Opc == ARM::tLDRpci) {
-  if (Opc == ARM::tPUSH) {
+    // Two special cases:
+    // 1) tPUSH does not have src/dst regs.
+    // 2) for Thumb1 code we sometimes materialize the constant via constpool
+    // load. Yes, this is pretty fragile, but for now I don't see better
+    // way... :(
     SrcReg = DstReg = ARM::SP;
   } else {
-    SrcReg =  MI->getOperand(1).getReg();
+    SrcReg = MI->getOperand(1).getReg();
     DstReg = MI->getOperand(0).getReg();
   }
 
@@ -875,6 +879,7 @@ void ARMAsmPrinter::EmitUnwindingInstruction(const MachineInstr *MI) {
         assert(0 && "Unsupported opcode for unwinding information");
       case ARM::MOVr:
       case ARM::tMOVgpr2gpr:
+      case ARM::tMOVgpr2tgpr:
         Offset = 0;
         break;
       case ARM::ADDri:
@@ -891,6 +896,9 @@ void ARMAsmPrinter::EmitUnwindingInstruction(const MachineInstr *MI) {
       case ARM::tADDrSPi:
         Offset = -MI->getOperand(2).getImm()*4;
         break;
+      case ARM::tLDRpci:
+        assert(0 && "Not implemented yet!");
+        break;
       }
 
       if (DstReg == FramePtr && FramePtr != ARM::SP)

llvm/lib/Target/ARM/ARMBaseRegisterInfo.cpp

@@ -806,7 +806,7 @@ emitLoadConstPool(MachineBasicBlock &MBB,
                   DebugLoc dl,
                   unsigned DestReg, unsigned SubIdx, int Val,
                   ARMCC::CondCodes Pred,
-                  unsigned PredReg) const {
+                  unsigned PredReg, unsigned MIFlags) const {
   MachineFunction &MF = *MBB.getParent();
   MachineConstantPool *ConstantPool = MF.getConstantPool();
   const Constant *C =
@@ -816,7 +816,8 @@ emitLoadConstPool(MachineBasicBlock &MBB,
   BuildMI(MBB, MBBI, dl, TII.get(ARM::LDRcp))
     .addReg(DestReg, getDefRegState(true), SubIdx)
     .addConstantPoolIndex(Idx)
-    .addImm(0).addImm(Pred).addReg(PredReg);
+    .addImm(0).addImm(Pred).addReg(PredReg)
+    .setMIFlags(MIFlags);
 }
 
 bool ARMBaseRegisterInfo::

llvm/lib/Target/ARM/ARMBaseRegisterInfo.h

@@ -176,7 +176,8 @@ public:
                                  unsigned DestReg, unsigned SubIdx,
                                  int Val,
                                  ARMCC::CondCodes Pred = ARMCC::AL,
-                                 unsigned PredReg = 0) const;
+                                 unsigned PredReg = 0,
+                                 unsigned MIFlags = MachineInstr::NoFlags)const;
 
   /// Code Generation virtual methods...
   virtual bool isReservedReg(const MachineFunction &MF, unsigned Reg) const;

llvm/lib/Target/ARM/Thumb1FrameLowering.cpp

@@ -34,13 +34,14 @@ bool Thumb1FrameLowering::hasReservedCallFrame(const MachineFunction &MF) const
   return !MF.getFrameInfo()->hasVarSizedObjects();
 }
 
-static void emitSPUpdate(MachineBasicBlock &MBB,
+static void
-                         MachineBasicBlock::iterator &MBBI,
+emitSPUpdate(MachineBasicBlock &MBB,
-                         const TargetInstrInfo &TII, DebugLoc dl,
+             MachineBasicBlock::iterator &MBBI,
-                         const Thumb1RegisterInfo &MRI,
+             const TargetInstrInfo &TII, DebugLoc dl,
-                         int NumBytes) {
+             const Thumb1RegisterInfo &MRI,
+             int NumBytes, unsigned MIFlags = MachineInstr::NoFlags)  {
   emitThumbRegPlusImmediate(MBB, MBBI, dl, ARM::SP, ARM::SP, NumBytes, TII,
-                            MRI);
+                            MRI, MIFlags);
 }
 
 void Thumb1FrameLowering::emitPrologue(MachineFunction &MF) const {
@@ -70,11 +71,13 @@ void Thumb1FrameLowering::emitPrologue(MachineFunction &MF) const {
   int FramePtrSpillFI = 0;
 
   if (VARegSaveSize)
-    emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -VARegSaveSize);
+    emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -VARegSaveSize,
+                 MachineInstr::FrameSetup);
 
   if (!AFI->hasStackFrame()) {
     if (NumBytes != 0)
-      emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -NumBytes);
+      emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -NumBytes,
+                   MachineInstr::FrameSetup);
     return;
   }
 
@@ -131,7 +134,8 @@ void Thumb1FrameLowering::emitPrologue(MachineFunction &MF) const {
   // Adjust FP so it point to the stack slot that contains the previous FP.
   if (hasFP(MF)) {
     BuildMI(MBB, MBBI, dl, TII.get(ARM::tADDrSPi), FramePtr)
-      .addFrameIndex(FramePtrSpillFI).addImm(0);
+      .addFrameIndex(FramePtrSpillFI).addImm(0)
+      .setMIFlags(MachineInstr::FrameSetup);
     if (NumBytes > 7)
       // If offset is > 7 then sp cannot be adjusted in a single instruction,
       // try restoring from fp instead.
@@ -140,7 +144,8 @@ void Thumb1FrameLowering::emitPrologue(MachineFunction &MF) const {
 
   if (NumBytes)
     // Insert it after all the callee-save spills.
-    emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -NumBytes);
+    emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -NumBytes,
+                 MachineInstr::FrameSetup);
 
   if (STI.isTargetELF() && hasFP(MF))
     MFI->setOffsetAdjustment(MFI->getOffsetAdjustment() -
@@ -307,6 +312,7 @@ spillCalleeSavedRegisters(MachineBasicBlock &MBB,
 
     MIB.addReg(Reg, getKillRegState(isKill));
   }
+  MIB.setMIFlags(MachineInstr::FrameSetup);
   return true;
 }
 

llvm/lib/Target/ARM/Thumb1RegisterInfo.cpp

@@ -50,13 +50,14 @@ Thumb1RegisterInfo::Thumb1RegisterInfo(const ARMBaseInstrInfo &tii,
 
 /// emitLoadConstPool - Emits a load from constpool to materialize the
 /// specified immediate.
-void Thumb1RegisterInfo::emitLoadConstPool(MachineBasicBlock &MBB,
+void
-                                           MachineBasicBlock::iterator &MBBI,
+Thumb1RegisterInfo::emitLoadConstPool(MachineBasicBlock &MBB,
-                                           DebugLoc dl,
+                                      MachineBasicBlock::iterator &MBBI,
-                                           unsigned DestReg, unsigned SubIdx,
+                                      DebugLoc dl,
-                                           int Val,
+                                      unsigned DestReg, unsigned SubIdx,
-                                           ARMCC::CondCodes Pred,
+                                      int Val,
-                                           unsigned PredReg) const {
+                                      ARMCC::CondCodes Pred, unsigned PredReg,
+                                      unsigned MIFlags) const {
   MachineFunction &MF = *MBB.getParent();
   MachineConstantPool *ConstantPool = MF.getConstantPool();
   const Constant *C = ConstantInt::get(
@@ -65,7 +66,8 @@ void Thumb1RegisterInfo::emitLoadConstPool(MachineBasicBlock &MBB,
 
   BuildMI(MBB, MBBI, dl, TII.get(ARM::tLDRpci))
           .addReg(DestReg, getDefRegState(true), SubIdx)
-          .addConstantPoolIndex(Idx).addImm(Pred).addReg(PredReg);
+          .addConstantPoolIndex(Idx).addImm(Pred).addReg(PredReg)
+          .setMIFlags(MIFlags)
 }
 
 
@@ -76,11 +78,12 @@ void Thumb1RegisterInfo::emitLoadConstPool(MachineBasicBlock &MBB,
 static
 void emitThumbRegPlusImmInReg(MachineBasicBlock &MBB,
                               MachineBasicBlock::iterator &MBBI,
+                              DebugLoc dl,
                               unsigned DestReg, unsigned BaseReg,
                               int NumBytes, bool CanChangeCC,
                               const TargetInstrInfo &TII,
                               const ARMBaseRegisterInfo& MRI,
-                              DebugLoc dl) {
+                              unsigned MIFlags = MachineInstr::NoFlags) {
     MachineFunction &MF = *MBB.getParent();
     bool isHigh = !isARMLowRegister(DestReg) ||
                   (BaseReg != 0 && !isARMLowRegister(BaseReg));
@@ -101,14 +104,15 @@ void emitThumbRegPlusImmInReg(MachineBasicBlock &MBB,
 
     if (NumBytes <= 255 && NumBytes >= 0)
       AddDefaultT1CC(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVi8), LdReg))
-        .addImm(NumBytes);
+        .addImm(NumBytes).setMIFlags(MIFlags);
     else if (NumBytes < 0 && NumBytes >= -255) {
       AddDefaultT1CC(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVi8), LdReg))
-        .addImm(NumBytes);
+        .addImm(NumBytes).setMIFlags(MIFlags);
       AddDefaultT1CC(BuildMI(MBB, MBBI, dl, TII.get(ARM::tRSB), LdReg))
-        .addReg(LdReg, RegState::Kill);
+        .addReg(LdReg, RegState::Kill).setMIFlags(MIFlags);
     } else
-      MRI.emitLoadConstPool(MBB, MBBI, dl, LdReg, 0, NumBytes);
+      MRI.emitLoadConstPool(MBB, MBBI, dl, LdReg, 0, NumBytes,
+                            ARMCC::AL, 0, MIFlags);
 
     // Emit add / sub.
     int Opc = (isSub) ? ARM::tSUBrr : (isHigh ? ARM::tADDhirr : ARM::tADDrr);
@@ -154,7 +158,8 @@ void llvm::emitThumbRegPlusImmediate(MachineBasicBlock &MBB,
                                      DebugLoc dl,
                                      unsigned DestReg, unsigned BaseReg,
                                      int NumBytes, const TargetInstrInfo &TII,
-                                     const ARMBaseRegisterInfo& MRI, unsigned) {
+                                     const ARMBaseRegisterInfo& MRI,
+                                     unsigned MIFlags) {
   bool isSub = NumBytes < 0;
   unsigned Bytes = (unsigned)NumBytes;
   if (isSub) Bytes = -NumBytes;
@@ -211,8 +216,9 @@ void llvm::emitThumbRegPlusImmediate(MachineBasicBlock &MBB,
   if (NumMIs > Threshold) {
     // This will expand into too many instructions. Load the immediate from a
     // constpool entry.
-    emitThumbRegPlusImmInReg(MBB, MBBI, DestReg, BaseReg, NumBytes, true, TII,
+    emitThumbRegPlusImmInReg(MBB, MBBI, dl,
-                             MRI, dl);
+                             DestReg, BaseReg, NumBytes, true,
+                             TII, MRI, MIFlags);
     return;
   }
 
@@ -224,11 +230,12 @@ void llvm::emitThumbRegPlusImmediate(MachineBasicBlock &MBB,
       Bytes -= ThisVal;
       const TargetInstrDesc &TID = TII.get(isSub ? ARM::tSUBi3 : ARM::tADDi3);
       const MachineInstrBuilder MIB =
-        AddDefaultT1CC(BuildMI(MBB, MBBI, dl, TID, DestReg));
+        AddDefaultT1CC(BuildMI(MBB, MBBI, dl, TID, DestReg).setMIFlags(MIFlags));
       AddDefaultPred(MIB.addReg(BaseReg, RegState::Kill).addImm(ThisVal));
     } else {
       BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr), DestReg)
-        .addReg(BaseReg, RegState::Kill);
+        .addReg(BaseReg, RegState::Kill)
+        .setMIFlags(MIFlags);
     }
     BaseReg = DestReg;
   }
@@ -243,9 +250,10 @@ void llvm::emitThumbRegPlusImmediate(MachineBasicBlock &MBB,
       MachineInstrBuilder MIB = BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg);
       if (NeedCC)
         MIB = AddDefaultT1CC(MIB);
-      MIB .addReg(DestReg).addImm(ThisVal);
+      MIB.addReg(DestReg).addImm(ThisVal);
       if (NeedPred)
         MIB = AddDefaultPred(MIB);
+      MIB.setMIFlags(MIFlags);
     }
     else {
       bool isKill = BaseReg != ARM::SP;
@@ -255,8 +263,9 @@ void llvm::emitThumbRegPlusImmediate(MachineBasicBlock &MBB,
       MIB.addReg(BaseReg, getKillRegState(isKill)).addImm(ThisVal);
       if (NeedPred)
         MIB = AddDefaultPred(MIB);
-      BaseReg = DestReg;
+      MIB.setMIFlags(MIFlags);
 
+      BaseReg = DestReg;
       if (Opc == ARM::tADDrSPi) {
         // r4 = add sp, imm
         // r4 = add r4, imm
@@ -274,7 +283,8 @@ void llvm::emitThumbRegPlusImmediate(MachineBasicBlock &MBB,
     const TargetInstrDesc &TID = TII.get(ExtraOpc);
     AddDefaultPred(AddDefaultT1CC(BuildMI(MBB, MBBI, dl, TID, DestReg))
                    .addReg(DestReg, RegState::Kill)
-                   .addImm(((unsigned)NumBytes) & 3));
+                   .addImm(((unsigned)NumBytes) & 3)
+                   .setMIFlags(MIFlags));
   }
 }
 
@@ -645,8 +655,8 @@ Thumb1RegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
     bool UseRR = false;
     if (Opcode == ARM::tRestore) {
       if (FrameReg == ARM::SP)
-        emitThumbRegPlusImmInReg(MBB, II, TmpReg, FrameReg,
+        emitThumbRegPlusImmInReg(MBB, II, dl, TmpReg, FrameReg,
-                                 Offset, false, TII, *this, dl);
+                                 Offset, false, TII, *this);
       else {
         emitLoadConstPool(MBB, II, dl, TmpReg, 0, Offset);
         UseRR = true;
@@ -668,8 +678,8 @@ Thumb1RegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
 
       if (Opcode == ARM::tSpill) {
         if (FrameReg == ARM::SP)
-          emitThumbRegPlusImmInReg(MBB, II, VReg, FrameReg,
+          emitThumbRegPlusImmInReg(MBB, II, dl, VReg, FrameReg,
-                                   Offset, false, TII, *this, dl);
+                                   Offset, false, TII, *this);
         else {
           emitLoadConstPool(MBB, II, dl, VReg, 0, Offset);
           UseRR = true;

llvm/lib/Target/ARM/Thumb1RegisterInfo.h

@@ -35,7 +35,8 @@ public:
                         DebugLoc dl,
                         unsigned DestReg, unsigned SubIdx, int Val,
                         ARMCC::CondCodes Pred = ARMCC::AL,
-                        unsigned PredReg = 0) const;
+                        unsigned PredReg = 0,
+                        unsigned MIFlags = MachineInstr::NoFlags) const;
 
   /// Code Generation virtual methods...
   void eliminateCallFramePseudoInstr(MachineFunction &MF,

llvm/lib/Target/ARM/Thumb2RegisterInfo.cpp

@@ -42,13 +42,14 @@ Thumb2RegisterInfo::Thumb2RegisterInfo(const ARMBaseInstrInfo &tii,
 
 /// emitLoadConstPool - Emits a load from constpool to materialize the
 /// specified immediate.
-void Thumb2RegisterInfo::emitLoadConstPool(MachineBasicBlock &MBB,
+void
-                                           MachineBasicBlock::iterator &MBBI,
+Thumb2RegisterInfo::emitLoadConstPool(MachineBasicBlock &MBB,
-                                           DebugLoc dl,
+                                      MachineBasicBlock::iterator &MBBI,
-                                           unsigned DestReg, unsigned SubIdx,
+                                      DebugLoc dl,
-                                           int Val,
+                                      unsigned DestReg, unsigned SubIdx,
-                                           ARMCC::CondCodes Pred,
+                                      int Val,
-                                           unsigned PredReg) const {
+                                      ARMCC::CondCodes Pred, unsigned PredReg,
+                                      unsigned MIFlags) const {
   MachineFunction &MF = *MBB.getParent();
   MachineConstantPool *ConstantPool = MF.getConstantPool();
   const Constant *C = ConstantInt::get(
@@ -57,5 +58,6 @@ void Thumb2RegisterInfo::emitLoadConstPool(MachineBasicBlock &MBB,
 
   BuildMI(MBB, MBBI, dl, TII.get(ARM::t2LDRpci))
     .addReg(DestReg, getDefRegState(true), SubIdx)
-    .addConstantPoolIndex(Idx).addImm((int64_t)ARMCC::AL).addReg(0);
+    .addConstantPoolIndex(Idx).addImm((int64_t)ARMCC::AL).addReg(0)
+    .setMIFlags(MIFlags);
 }

llvm/lib/Target/ARM/Thumb2RegisterInfo.h

@@ -35,7 +35,8 @@ public:
                          DebugLoc dl,
                          unsigned DestReg, unsigned SubIdx, int Val,
                          ARMCC::CondCodes Pred = ARMCC::AL,
-                         unsigned PredReg = 0) const;
+                         unsigned PredReg = 0,
+                         unsigned MIFlags = MachineInstr::NoFlags) const;
 };
 }