Thumb1 ADD/SUB SP instructions are predicable in Thumb2 mode.

Add the predicate operand to the instructions. Update the back end
accordingly where the instructions are used. Restrict the SP operands
to actually only be SP, as otherwise these break assembly parsing for the
normal instruction variants.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138445 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/ARM/ARMBaseRegisterInfo.cpp b/lib/Target/ARM/ARMBaseRegisterInfo.cpp
index d888c1da0645544235394c18ce729b1755545d2c..0070d7acb72fd8525128f85c28bf1c4e13f8b913 100644 (file)
--- a/lib/Target/ARM/ARMBaseRegisterInfo.cpp
+++ b/lib/Target/ARM/ARMBaseRegisterInfo.cpp
@@ -1098,11 +1098,11 @@ materializeFrameBaseRegister(MachineBasicBlock *MBB,
   MachineRegisterInfo &MRI = MBB->getParent()->getRegInfo();
   MRI.constrainRegClass(BaseReg, TII.getRegClass(MCID, 0, this));
 
-  MachineInstrBuilder MIB = BuildMI(*MBB, Ins, DL, MCID, BaseReg)
-    .addFrameIndex(FrameIdx).addImm(Offset);
+  MachineInstrBuilder MIB = AddDefaultPred(BuildMI(*MBB, Ins, DL, MCID, BaseReg)
+    .addFrameIndex(FrameIdx).addImm(Offset));
 
   if (!AFI->isThumb1OnlyFunction())
-    AddDefaultCC(AddDefaultPred(MIB));
+    AddDefaultCC(MIB);
 }
 
 void

diff --git a/lib/Target/ARM/ARMISelDAGToDAG.cpp b/lib/Target/ARM/ARMISelDAGToDAG.cpp
index ceceddb248a4b5c6ce4cf10b3dec996f900fa743..7e4450fced20d9c1f46ca2fc4175f44282086d20 100644 (file)
--- a/lib/Target/ARM/ARMISelDAGToDAG.cpp
+++ b/lib/Target/ARM/ARMISelDAGToDAG.cpp
@@ -2338,8 +2338,9 @@ SDNode *ARMDAGToDAGISel::Select(SDNode *N) {
     int FI = cast<FrameIndexSDNode>(N)->getIndex();
     SDValue TFI = CurDAG->getTargetFrameIndex(FI, TLI.getPointerTy());
     if (Subtarget->isThumb1Only()) {
-      return CurDAG->SelectNodeTo(N, ARM::tADDrSPi, MVT::i32, TFI,
-                                  CurDAG->getTargetConstant(0, MVT::i32));
+      SDValue Ops[] = { TFI, CurDAG->getTargetConstant(0, MVT::i32),
+                        getAL(CurDAG), CurDAG->getRegister(0, MVT::i32) };
+      return CurDAG->SelectNodeTo(N, ARM::tADDrSPi, MVT::i32, Ops, 4);
     } else {
       unsigned Opc = ((Subtarget->isThumb() && Subtarget->hasThumb2()) ?
                       ARM::t2ADDri : ARM::ADDri);

diff --git a/lib/Target/ARM/ARMInstrThumb.td b/lib/Target/ARM/ARMInstrThumb.td
index 419da021724015e6e762bf8832b776dd81def3e3..4d3bd079a83734b6460d9ceebdff4ab757e47ece 100644 (file)
--- a/lib/Target/ARM/ARMInstrThumb.td
+++ b/lib/Target/ARM/ARMInstrThumb.td
@@ -305,8 +305,8 @@ def tPICADD : TIt<(outs GPR:$dst), (ins GPR:$lhs, pclabel:$cp), IIC_iALUr, "",
 // This is rematerializable, which is particularly useful for taking the
 // address of locals.
 let isReMaterializable = 1 in
-def tADDrSPi : T1I<(outs tGPR:$dst), (ins GPR:$sp, t_imm_s4:$rhs), IIC_iALUi,
-                   "add\t$dst, $sp, $rhs", []>,
+def tADDrSPi : T1pI<(outs tGPR:$dst), (ins GPRsp:$sp, t_imm_s4:$rhs), IIC_iALUi,
+                   "add", "\t$dst, $sp, $rhs", []>,
                T1Encoding<{1,0,1,0,1,?}> {
   // A6.2 & A8.6.8
   bits<3> dst;
@@ -317,8 +317,8 @@ def tADDrSPi : T1I<(outs tGPR:$dst), (ins GPR:$sp, t_imm_s4:$rhs), IIC_iALUi,
 }
 
 // ADD sp, sp, #<imm7>
-def tADDspi : TIt<(outs GPR:$dst), (ins GPR:$lhs, t_imm_s4:$rhs), IIC_iALUi,
-                  "add\t$dst, $rhs", []>,
+def tADDspi : T1pIt<(outs GPRsp:$Rdn), (ins GPRsp:$Rn, t_imm_s4:$rhs),
+                     IIC_iALUi, "add", "\t$Rdn, $rhs", []>,
               T1Misc<{0,0,0,0,0,?,?}> {
   // A6.2.5 & A8.6.8
   bits<7> rhs;
@@ -328,8 +328,8 @@ def tADDspi : TIt<(outs GPR:$dst), (ins GPR:$lhs, t_imm_s4:$rhs), IIC_iALUi,
 
 // SUB sp, sp, #<imm7>
 // FIXME: The encoding and the ASM string don't match up.
-def tSUBspi : TIt<(outs GPR:$dst), (ins GPR:$lhs, t_imm_s4:$rhs), IIC_iALUi,
-                  "sub\t$dst, $rhs", []>,
+def tSUBspi : T1pIt<(outs GPRsp:$Rdn), (ins GPRsp:$Rn, t_imm_s4:$rhs),
+                    IIC_iALUi, "sub", "\t$Rdn, $rhs", []>,
               T1Misc<{0,0,0,0,1,?,?}> {
   // A6.2.5 & A8.6.214
   bits<7> rhs;
@@ -338,25 +338,25 @@ def tSUBspi : TIt<(outs GPR:$dst), (ins GPR:$lhs, t_imm_s4:$rhs), IIC_iALUi,
 }
 
 // ADD <Rm>, sp
-def tADDrSP : TIt<(outs GPR:$dst), (ins GPR:$lhs, GPR:$rhs), IIC_iALUr,
-                  "add\t$dst, $rhs", []>,
+def tADDrSP : T1pIt<(outs GPR:$Rdn), (ins GPR:$Rn, GPRsp:$rhs), IIC_iALUr,
+                  "add", "\t$Rdn, $rhs", []>,
               T1Special<{0,0,?,?}> {
   // A8.6.9 Encoding T1
-  bits<4> dst;
-  let Inst{7}   = dst{3};
+  bits<4> Rdn;
+  let Inst{7}   = Rdn{3};
   let Inst{6-3} = 0b1101;
-  let Inst{2-0} = dst{2-0};
+  let Inst{2-0} = Rdn{2-0};
   let DecoderMethod = "DecodeThumbAddSPReg";
 }
 
 // ADD sp, <Rm>
-def tADDspr : TIt<(outs GPR:$dst), (ins GPR:$lhs, GPR:$rhs), IIC_iALUr,
-                  "add\t$dst, $rhs", []>,
+def tADDspr : T1pIt<(outs GPRsp:$Rdn), (ins GPRsp:$Rn, GPR:$rhs), IIC_iALUr,
+                  "add", "\t$Rdn, $rhs", []>,
               T1Special<{0,0,?,?}> {
   // A8.6.9 Encoding T2
-  bits<4> dst;
+  bits<4> Rdn;
   let Inst{7} = 1;
-  let Inst{6-3} = dst;
+  let Inst{6-3} = Rdn;
   let Inst{2-0} = 0b101;
   let DecoderMethod = "DecodeThumbAddSPReg";
 }

diff --git a/lib/Target/ARM/ARMRegisterInfo.td b/lib/Target/ARM/ARMRegisterInfo.td
index cf3d66873b4dc3ba900225ec768d0facb09683c7..50f925944931c1d0c8a6db804ee90404b94907a7 100644 (file)
--- a/lib/Target/ARM/ARMRegisterInfo.td
+++ b/lib/Target/ARM/ARMRegisterInfo.td
@@ -225,6 +225,13 @@ def GPRnopc : RegisterClass<"ARM", [i32], 32, (sub GPR, PC)> {
   }];
 }
 
+// GPRsp - Only the SP is legal. Used by Thumb1 instructions that want the
+// implied SP argument list.
+// FIXME: It would be better to not use this at all and refactor the
+// instructions to not have SP an an explicit argument. That makes
+// frame index resolution a bit trickier, though.
+def GPRsp : RegisterClass<"ARM", [i32], 32, (add SP)>;
+
 // restricted GPR register class. Many Thumb2 instructions allow the full
 // register range for operands, but have undefined behaviours when PC
 // or SP (R13 or R15) are used. The ARM ISA refers to these operands

diff --git a/lib/Target/ARM/Thumb1FrameLowering.cpp b/lib/Target/ARM/Thumb1FrameLowering.cpp
index c258870e48a58025a5984d98d874eff769e8dbbe..c136906807331976ed0a72bc3b9beed83682bbcc 100644 (file)
--- a/lib/Target/ARM/Thumb1FrameLowering.cpp
+++ b/lib/Target/ARM/Thumb1FrameLowering.cpp
@@ -133,9 +133,9 @@ 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)
+    AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tADDrSPi), FramePtr)
       .addFrameIndex(FramePtrSpillFI).addImm(0)
-      .setMIFlags(MachineInstr::FrameSetup);
+      .setMIFlags(MachineInstr::FrameSetup));
     if (NumBytes > 508)
       // If offset is > 508 then sp cannot be adjusted in a single instruction,
       // try restoring from fp instead.

diff --git a/lib/Target/ARM/Thumb1RegisterInfo.cpp b/lib/Target/ARM/Thumb1RegisterInfo.cpp
index dd066e891c3878d8ad1af49154cfdd90a179c961..d6b03778096761268090e898b6f87a400ab6eb44 100644 (file)
--- a/lib/Target/ARM/Thumb1RegisterInfo.cpp
+++ b/lib/Target/ARM/Thumb1RegisterInfo.cpp
@@ -181,7 +181,6 @@ void llvm::emitThumbRegPlusImmediate(MachineBasicBlock &MBB,
   int Opc = 0;
   int ExtraOpc = 0;
   bool NeedCC = false;
-  bool NeedPred = false;
 
   if (DestReg == BaseReg && BaseReg == ARM::SP) {
     assert(isMul4 && "Thumb sp inc / dec size must be multiple of 4!");
@@ -216,7 +215,7 @@ void llvm::emitThumbRegPlusImmediate(MachineBasicBlock &MBB,
     } else {
       Opc = isSub ? ARM::tSUBi8 : ARM::tADDi8;
       NumBits = 8;
-      NeedPred = NeedCC = true;
+      NeedCC = true;
     }
     isTwoAddr = true;
   }
@@ -262,8 +261,7 @@ void llvm::emitThumbRegPlusImmediate(MachineBasicBlock &MBB,
       if (NeedCC)
         MIB = AddDefaultT1CC(MIB);
       MIB.addReg(DestReg).addImm(ThisVal);
-      if (NeedPred)
-        MIB = AddDefaultPred(MIB);
+      MIB = AddDefaultPred(MIB);
       MIB.setMIFlags(MIFlags);
     } else {
       bool isKill = BaseReg != ARM::SP;
@@ -271,8 +269,7 @@ void llvm::emitThumbRegPlusImmediate(MachineBasicBlock &MBB,
       if (NeedCC)
         MIB = AddDefaultT1CC(MIB);
       MIB.addReg(BaseReg, getKillRegState(isKill)).addImm(ThisVal);
-      if (NeedPred)
-        MIB = AddDefaultPred(MIB);
+      MIB = AddDefaultPred(MIB);
       MIB.setMIFlags(MIFlags);
 
       BaseReg = DestReg;
@@ -284,7 +281,7 @@ void llvm::emitThumbRegPlusImmediate(MachineBasicBlock &MBB,
         Scale = 1;
         Chunk = ((1 << NumBits) - 1) * Scale;
         Opc = isSub ? ARM::tSUBi8 : ARM::tADDi8;
-        NeedPred = NeedCC = isTwoAddr = true;
+        NeedCC = isTwoAddr = true;
       }
     }
   }
@@ -404,7 +401,6 @@ rewriteFrameIndex(MachineBasicBlock::iterator II, unsigned FrameRegIdx,
     unsigned Scale = 1;
     if (FrameReg != ARM::SP) {
       Opcode = ARM::tADDi3;
-      MI.setDesc(TII.get(Opcode));
       NumBits = 3;
     } else {
       NumBits = 8;
@@ -418,10 +414,9 @@ rewriteFrameIndex(MachineBasicBlock::iterator II, unsigned FrameRegIdx,
       // Turn it into a move.
       MI.setDesc(TII.get(ARM::tMOVr));
       MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
-      // Remove offset and add predicate operands.
+      // Remove offset
       MI.RemoveOperand(FrameRegIdx+1);
       MachineInstrBuilder MIB(&MI);
-      AddDefaultPred(MIB);
       return true;
     }
 
@@ -430,6 +425,7 @@ rewriteFrameIndex(MachineBasicBlock::iterator II, unsigned FrameRegIdx,
     if (((Offset / Scale) & ~Mask) == 0) {
       // Replace the FrameIndex with sp / fp
       if (Opcode == ARM::tADDi3) {
+        MI.setDesc(TII.get(Opcode));
         removeOperands(MI, FrameRegIdx);
         MachineInstrBuilder MIB(&MI);
         AddDefaultPred(AddDefaultT1CC(MIB).addReg(FrameReg)
@@ -478,10 +474,6 @@ rewriteFrameIndex(MachineBasicBlock::iterator II, unsigned FrameRegIdx,
       MI.setDesc(TII.get(ARM::tADDhirr));
       MI.getOperand(FrameRegIdx).ChangeToRegister(DestReg, false, false, true);
       MI.getOperand(FrameRegIdx+1).ChangeToRegister(FrameReg, false);
-      if (Opcode == ARM::tADDi3) {
-        MachineInstrBuilder MIB(&MI);
-        AddDefaultPred(MIB);
-      }
     }
     return true;
   } else {

diff --git a/lib/Target/ARM/Thumb2InstrInfo.cpp b/lib/Target/ARM/Thumb2InstrInfo.cpp
index bc104ebc78ac71efcafb41281c7eb7722831fd2f..cf040c822de95a45f440c16ab794d09ad5ebac40 100644 (file)
--- a/lib/Target/ARM/Thumb2InstrInfo.cpp
+++ b/lib/Target/ARM/Thumb2InstrInfo.cpp
@@ -235,9 +235,8 @@ void llvm::emitT2RegPlusImmediate(MachineBasicBlock &MBB,
       if (DestReg == ARM::SP && (ThisVal < ((1 << 7)-1) * 4)) {
         assert((ThisVal & 3) == 0 && "Stack update is not multiple of 4?");
         Opc = isSub ? ARM::tSUBspi : ARM::tADDspi;
-        // FIXME: Fix Thumb1 immediate encoding.
-        BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
-          .addReg(BaseReg).addImm(ThisVal/4).setMIFlags(MIFlags);
+        AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
+          .addReg(BaseReg).addImm(ThisVal/4).setMIFlags(MIFlags));
         NumBytes = 0;
         continue;
       }

diff --git a/lib/Target/ARM/Thumb2SizeReduction.cpp b/lib/Target/ARM/Thumb2SizeReduction.cpp
index 130be9ac7de244bf281ccd35688da9641502e45a..89a155c5a7f5c2af5a52bfcd1f1ec54a412ec42c 100644 (file)
--- a/lib/Target/ARM/Thumb2SizeReduction.cpp
+++ b/lib/Target/ARM/Thumb2SizeReduction.cpp
@@ -507,6 +507,7 @@ Thumb2SizeReduce::ReduceSpecial(MachineBasicBlock &MBB, MachineInstr *MI,
       .addOperand(MI->getOperand(0))
       .addOperand(MI->getOperand(1))
       .addImm(Imm / 4); // The tADDrSPi has an implied scale by four.
+    AddDefaultPred(MIB);
 
     // Transfer MI flags.
     MIB.setMIFlags(MI->getFlags());

diff --git a/utils/TableGen/EDEmitter.cpp b/utils/TableGen/EDEmitter.cpp
index 37fb6adf50a3146019d669400a395ed3e15a9e1e..852b9bf125bc5db9bf1926a20bd1e2c35e7c7c82 100644 (file)
--- a/utils/TableGen/EDEmitter.cpp
+++ b/utils/TableGen/EDEmitter.cpp
@@ -556,6 +556,7 @@ static int ARMFlagFromOpName(LiteralConstantEmitter *type,
   REG("GPR");
   REG("rGPR");
   REG("GPRnopc");
+  REG("GPRsp");
   REG("tcGPR");
   REG("cc_out");
   REG("s_cc_out");