[X86] Make isel select the shorter form of jump instructions instead of the long form.

The assembler backend will relax to the long form if necessary. This removes a swap from long form to short form in the MCInstLowering code. Selecting the long form used to be required by the old JIT.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225242 91177308-0d34-0410-b5e6-96231b3b80d8

8 files changed, 97 insertions, 120 deletions

diff --git a/lib/Target/X86/AsmParser/X86AsmInstrumentation.cpp b/lib/Target/X86/AsmParser/X86AsmInstrumentation.cpp
index 447ab9de95b..543af8e4e77 100644
--- a/lib/Target/X86/AsmParser/X86AsmInstrumentation.cpp
+++ b/lib/Target/X86/AsmParser/X86AsmInstrumentation.cpp
@@ -656,7 +656,7 @@ void X86AddressSanitizer32::InstrumentMemOperandSmall(
       Out, MCInstBuilder(X86::TEST8rr).addReg(ShadowRegI8).addReg(ShadowRegI8));
   MCSymbol *DoneSym = Ctx.CreateTempSymbol();
   const MCExpr *DoneExpr = MCSymbolRefExpr::Create(DoneSym, Ctx);
-  EmitInstruction(Out, MCInstBuilder(X86::JE_4).addExpr(DoneExpr));
+  EmitInstruction(Out, MCInstBuilder(X86::JE_1).addExpr(DoneExpr));
 
   EmitInstruction(Out, MCInstBuilder(X86::MOV32rr).addReg(ScratchRegI32).addReg(
                            AddressRegI32));
@@ -690,7 +690,7 @@ void X86AddressSanitizer32::InstrumentMemOperandSmall(
       MCInstBuilder(X86::MOVSX32rr8).addReg(ShadowRegI32).addReg(ShadowRegI8));
   EmitInstruction(Out, MCInstBuilder(X86::CMP32rr).addReg(ScratchRegI32).addReg(
                            ShadowRegI32));
-  EmitInstruction(Out, MCInstBuilder(X86::JL_4).addExpr(DoneExpr));
+  EmitInstruction(Out, MCInstBuilder(X86::JL_1).addExpr(DoneExpr));
 
   EmitCallAsanReport(AccessSize, IsWrite, Ctx, Out, RegCtx);
   EmitLabel(Out, DoneSym);
@@ -731,7 +731,7 @@ void X86AddressSanitizer32::InstrumentMemOperandLarge(
   }
   MCSymbol *DoneSym = Ctx.CreateTempSymbol();
   const MCExpr *DoneExpr = MCSymbolRefExpr::Create(DoneSym, Ctx);
-  EmitInstruction(Out, MCInstBuilder(X86::JE_4).addExpr(DoneExpr));
+  EmitInstruction(Out, MCInstBuilder(X86::JE_1).addExpr(DoneExpr));
 
   EmitCallAsanReport(AccessSize, IsWrite, Ctx, Out, RegCtx);
   EmitLabel(Out, DoneSym);
@@ -747,7 +747,7 @@ void X86AddressSanitizer32::InstrumentMOVSImpl(unsigned AccessSize,
   const MCExpr *DoneExpr = MCSymbolRefExpr::Create(DoneSym, Ctx);
   EmitInstruction(
       Out, MCInstBuilder(X86::TEST32rr).addReg(X86::ECX).addReg(X86::ECX));
-  EmitInstruction(Out, MCInstBuilder(X86::JE_4).addExpr(DoneExpr));
+  EmitInstruction(Out, MCInstBuilder(X86::JE_1).addExpr(DoneExpr));
 
   // Instrument first and last elements in src and dst range.
   InstrumentMOVSBase(X86::EDI /* DstReg */, X86::ESI /* SrcReg */,
@@ -927,7 +927,7 @@ void X86AddressSanitizer64::InstrumentMemOperandSmall(
       Out, MCInstBuilder(X86::TEST8rr).addReg(ShadowRegI8).addReg(ShadowRegI8));
   MCSymbol *DoneSym = Ctx.CreateTempSymbol();
   const MCExpr *DoneExpr = MCSymbolRefExpr::Create(DoneSym, Ctx);
-  EmitInstruction(Out, MCInstBuilder(X86::JE_4).addExpr(DoneExpr));
+  EmitInstruction(Out, MCInstBuilder(X86::JE_1).addExpr(DoneExpr));
 
   EmitInstruction(Out, MCInstBuilder(X86::MOV32rr).addReg(ScratchRegI32).addReg(
                            AddressRegI32));
@@ -961,7 +961,7 @@ void X86AddressSanitizer64::InstrumentMemOperandSmall(
       MCInstBuilder(X86::MOVSX32rr8).addReg(ShadowRegI32).addReg(ShadowRegI8));
   EmitInstruction(Out, MCInstBuilder(X86::CMP32rr).addReg(ScratchRegI32).addReg(
                            ShadowRegI32));
-  EmitInstruction(Out, MCInstBuilder(X86::JL_4).addExpr(DoneExpr));
+  EmitInstruction(Out, MCInstBuilder(X86::JL_1).addExpr(DoneExpr));
 
   EmitCallAsanReport(AccessSize, IsWrite, Ctx, Out, RegCtx);
   EmitLabel(Out, DoneSym);
@@ -1003,7 +1003,7 @@ void X86AddressSanitizer64::InstrumentMemOperandLarge(
 
   MCSymbol *DoneSym = Ctx.CreateTempSymbol();
   const MCExpr *DoneExpr = MCSymbolRefExpr::Create(DoneSym, Ctx);
-  EmitInstruction(Out, MCInstBuilder(X86::JE_4).addExpr(DoneExpr));
+  EmitInstruction(Out, MCInstBuilder(X86::JE_1).addExpr(DoneExpr));
 
   EmitCallAsanReport(AccessSize, IsWrite, Ctx, Out, RegCtx);
   EmitLabel(Out, DoneSym);
@@ -1019,7 +1019,7 @@ void X86AddressSanitizer64::InstrumentMOVSImpl(unsigned AccessSize,
   const MCExpr *DoneExpr = MCSymbolRefExpr::Create(DoneSym, Ctx);
   EmitInstruction(
       Out, MCInstBuilder(X86::TEST64rr).addReg(X86::RCX).addReg(X86::RCX));
-  EmitInstruction(Out, MCInstBuilder(X86::JE_4).addExpr(DoneExpr));
+  EmitInstruction(Out, MCInstBuilder(X86::JE_1).addExpr(DoneExpr));
 
   // Instrument first and last elements in src and dst range.
   InstrumentMOVSBase(X86::RDI /* DstReg */, X86::RSI /* SrcReg */,
diff --git a/lib/Target/X86/X86FastISel.cpp b/lib/Target/X86/X86FastISel.cpp
index d4459eec8ba..7849801f765 100644
--- a/lib/Target/X86/X86FastISel.cpp
+++ b/lib/Target/X86/X86FastISel.cpp
@@ -1362,7 +1362,7 @@ bool X86FastISel::X86SelectBranch(const Instruction *I) {
       // X86 requires a second branch to handle UNE (and OEQ, which is mapped
       // to UNE above).
       if (NeedExtraBranch) {
-        BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(X86::JP_4))
+        BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(X86::JP_1))
           .addMBB(TrueMBB);
       }
 
@@ -1399,10 +1399,10 @@ bool X86FastISel::X86SelectBranch(const Instruction *I) {
         BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(TestOpc))
           .addReg(OpReg).addImm(1);
 
-        unsigned JmpOpc = X86::JNE_4;
+        unsigned JmpOpc = X86::JNE_1;
         if (FuncInfo.MBB->isLayoutSuccessor(TrueMBB)) {
           std::swap(TrueMBB, FalseMBB);
-          JmpOpc = X86::JE_4;
+          JmpOpc = X86::JE_1;
         }
 
         BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(JmpOpc))
@@ -1444,7 +1444,7 @@ bool X86FastISel::X86SelectBranch(const Instruction *I) {
 
   BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(X86::TEST8ri))
     .addReg(OpReg).addImm(1);
-  BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(X86::JNE_4))
+  BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(X86::JNE_1))
     .addMBB(TrueMBB);
   fastEmitBranch(FalseMBB, DbgLoc);
   uint32_t BranchWeight = 0;
diff --git a/lib/Target/X86/X86FrameLowering.cpp b/lib/Target/X86/X86FrameLowering.cpp
index 95bca7d936f..8779acc6a08 100644
--- a/lib/Target/X86/X86FrameLowering.cpp
+++ b/lib/Target/X86/X86FrameLowering.cpp
@@ -1617,7 +1617,7 @@ X86FrameLowering::adjustForSegmentedStacks(MachineFunction &MF) const {
 
   // This jump is taken if SP >= (Stacklet Limit + Stack Space required).
   // It jumps to normal execution of the function body.
-  BuildMI(checkMBB, DL, TII.get(X86::JA_4)).addMBB(&prologueMBB);
+  BuildMI(checkMBB, DL, TII.get(X86::JA_1)).addMBB(&prologueMBB);
 
   // On 32 bit we first push the arguments size and then the frame size. On 64
   // bit, we pass the stack frame size in r10 and the argument size in r11.
@@ -1821,7 +1821,7 @@ void X86FrameLowering::adjustForHiPEPrologue(MachineFunction &MF) const {
     // SPLimitOffset is in a fixed heap location (pointed by BP).
     addRegOffset(BuildMI(stackCheckMBB, DL, TII.get(CMPop))
                  .addReg(ScratchReg), PReg, false, SPLimitOffset);
-    BuildMI(stackCheckMBB, DL, TII.get(X86::JAE_4)).addMBB(&prologueMBB);
+    BuildMI(stackCheckMBB, DL, TII.get(X86::JAE_1)).addMBB(&prologueMBB);
 
     // Create new MBB for IncStack:
     BuildMI(incStackMBB, DL, TII.get(CALLop)).
@@ -1830,7 +1830,7 @@ void X86FrameLowering::adjustForHiPEPrologue(MachineFunction &MF) const {
                  SPReg, false, -MaxStack);
     addRegOffset(BuildMI(incStackMBB, DL, TII.get(CMPop))
                  .addReg(ScratchReg), PReg, false, SPLimitOffset);
-    BuildMI(incStackMBB, DL, TII.get(X86::JLE_4)).addMBB(incStackMBB);
+    BuildMI(incStackMBB, DL, TII.get(X86::JLE_1)).addMBB(incStackMBB);
 
     stackCheckMBB->addSuccessor(&prologueMBB, 99);
     stackCheckMBB->addSuccessor(incStackMBB, 1);
diff --git a/lib/Target/X86/X86ISelDAGToDAG.cpp b/lib/Target/X86/X86ISelDAGToDAG.cpp
index 7f177bda9ae..7fe8e8b344a 100644
--- a/lib/Target/X86/X86ISelDAGToDAG.cpp
+++ b/lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -1891,8 +1891,8 @@ static bool HasNoSignedComparisonUses(SDNode *N) {
       case X86::SETEr: case X86::SETNEr: case X86::SETPr: case X86::SETNPr:
       case X86::SETAm: case X86::SETAEm: case X86::SETBm: case X86::SETBEm:
       case X86::SETEm: case X86::SETNEm: case X86::SETPm: case X86::SETNPm:
-      case X86::JA_4: case X86::JAE_4: case X86::JB_4: case X86::JBE_4:
-      case X86::JE_4: case X86::JNE_4: case X86::JP_4: case X86::JNP_4:
+      case X86::JA_1: case X86::JAE_1: case X86::JB_1: case X86::JBE_1:
+      case X86::JE_1: case X86::JNE_1: case X86::JP_1: case X86::JNP_1:
       case X86::CMOVA16rr: case X86::CMOVA16rm:
       case X86::CMOVA32rr: case X86::CMOVA32rm:
       case X86::CMOVA64rr: case X86::CMOVA64rm:
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index e8bac7b9312..9e068616ddc 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -20527,7 +20527,7 @@ X86TargetLowering::EmitVAARG64WithCustomInserter(
       .setMemRefs(MMOBegin, MMOEnd);
 
     // Jump to endMBB
-    BuildMI(offsetMBB, DL, TII->get(X86::JMP_4))
+    BuildMI(offsetMBB, DL, TII->get(X86::JMP_1))
       .addMBB(endMBB);
   }
 
@@ -20641,7 +20641,7 @@ X86TargetLowering::EmitVAStartSaveXMMRegsWithCustomInserter(
   if (!Subtarget->isTargetWin64()) {
     // If %al is 0, branch around the XMM save block.
     BuildMI(MBB, DL, TII->get(X86::TEST8rr)).addReg(CountReg).addReg(CountReg);
-    BuildMI(MBB, DL, TII->get(X86::JE_4)).addMBB(EndMBB);
+    BuildMI(MBB, DL, TII->get(X86::JE_1)).addMBB(EndMBB);
     MBB->addSuccessor(EndMBB);
   }
 
@@ -20845,7 +20845,7 @@ X86TargetLowering::EmitLoweredSegAlloca(MachineInstr *MI,
   BuildMI(BB, DL, TII->get(IsLP64 ? X86::CMP64mr:X86::CMP32mr))
     .addReg(0).addImm(1).addReg(0).addImm(TlsOffset).addReg(TlsReg)
     .addReg(SPLimitVReg);
-  BuildMI(BB, DL, TII->get(X86::JG_4)).addMBB(mallocMBB);
+  BuildMI(BB, DL, TII->get(X86::JG_1)).addMBB(mallocMBB);
 
   // bumpMBB simply decreases the stack pointer, since we know the current
   // stacklet has enough space.
@@ -20853,7 +20853,7 @@ X86TargetLowering::EmitLoweredSegAlloca(MachineInstr *MI,
     .addReg(SPLimitVReg);
   BuildMI(bumpMBB, DL, TII->get(TargetOpcode::COPY), bumpSPPtrVReg)
     .addReg(SPLimitVReg);
-  BuildMI(bumpMBB, DL, TII->get(X86::JMP_4)).addMBB(continueMBB);
+  BuildMI(bumpMBB, DL, TII->get(X86::JMP_1)).addMBB(continueMBB);
 
   // Calls into a routine in libgcc to allocate more space from the heap.
   const uint32_t *RegMask = MF->getTarget()
@@ -20892,7 +20892,7 @@ X86TargetLowering::EmitLoweredSegAlloca(MachineInstr *MI,
 
   BuildMI(mallocMBB, DL, TII->get(TargetOpcode::COPY), mallocPtrVReg)
     .addReg(IsLP64 ? X86::RAX : X86::EAX);
-  BuildMI(mallocMBB, DL, TII->get(X86::JMP_4)).addMBB(continueMBB);
+  BuildMI(mallocMBB, DL, TII->get(X86::JMP_1)).addMBB(continueMBB);
 
   // Set up the CFG correctly.
   BB->addSuccessor(bumpMBB);
@@ -21171,7 +21171,7 @@ X86TargetLowering::emitEHSjLjSetJmp(MachineInstr *MI,
       .setMIFlag(MachineInstr::FrameSetup);
   }
   BuildMI(restoreMBB, DL, TII->get(X86::MOV32ri), restoreDstReg).addImm(1);
-  BuildMI(restoreMBB, DL, TII->get(X86::JMP_4)).addMBB(sinkMBB);
+  BuildMI(restoreMBB, DL, TII->get(X86::JMP_1)).addMBB(sinkMBB);
   restoreMBB->addSuccessor(sinkMBB);
 
   MI->eraseFromParent();
diff --git a/lib/Target/X86/X86InstrControl.td b/lib/Target/X86/X86InstrControl.td
index 80ff5e94b39..48c9897cd03 100644
--- a/lib/Target/X86/X86InstrControl.td
+++ b/lib/Target/X86/X86InstrControl.td
@@ -57,33 +57,32 @@ let isTerminator = 1, isReturn = 1, isBarrier = 1,
 
 // Unconditional branches.
 let isBarrier = 1, isBranch = 1, isTerminator = 1, SchedRW = [WriteJump] in {
-  def JMP_4 : Ii32PCRel<0xE9, RawFrm, (outs), (ins brtarget:$dst),
-                        "jmp\t$dst", [(br bb:$dst)], IIC_JMP_REL>, OpSize32;
-  def JMP_2 : Ii16PCRel<0xE9, RawFrm, (outs), (ins brtarget:$dst),
-                        "jmp\t$dst", [(br bb:$dst)], IIC_JMP_REL>, OpSize16,
-                        Requires<[In16BitMode]>;
-  let hasSideEffects = 0 in
   def JMP_1 : Ii8PCRel<0xEB, RawFrm, (outs), (ins brtarget8:$dst),
-                       "jmp\t$dst", [], IIC_JMP_REL>;
+                       "jmp\t$dst", [(br bb:$dst)], IIC_JMP_REL>;
+  let hasSideEffects = 0 in {
+    def JMP_2 : Ii16PCRel<0xE9, RawFrm, (outs), (ins brtarget:$dst),
+                          "jmp\t$dst", [], IIC_JMP_REL>, OpSize16;
+    def JMP_4 : Ii32PCRel<0xE9, RawFrm, (outs), (ins brtarget:$dst),
+                          "jmp\t$dst", [], IIC_JMP_REL>, OpSize32;
+  }
 }
 
 // Conditional Branches.
 let isBranch = 1, isTerminator = 1, Uses = [EFLAGS], SchedRW = [WriteJump] in {
   multiclass ICBr<bits<8> opc1, bits<8> opc4, string asm, PatFrag Cond> {
-    let hasSideEffects = 0 in
-    def _1 : Ii8PCRel <opc1, RawFrm, (outs), (ins brtarget8:$dst), asm, [],
-                       IIC_Jcc>;
-    def _2 : Ii16PCRel<opc4, RawFrm, (outs), (ins brtarget:$dst), asm,
-                       [(X86brcond bb:$dst, Cond, EFLAGS)], IIC_Jcc>, OpSize16,
-		       TB, Requires<[In16BitMode]>;
-    def _4 : Ii32PCRel<opc4, RawFrm, (outs), (ins brtarget:$dst), asm,
-                       [(X86brcond bb:$dst, Cond, EFLAGS)], IIC_Jcc>, TB,
-             OpSize32;
+    def _1 : Ii8PCRel <opc1, RawFrm, (outs), (ins brtarget8:$dst), asm,
+                       [(X86brcond bb:$dst, Cond, EFLAGS)], IIC_Jcc>;
+    let hasSideEffects = 0 in {
+      def _2 : Ii16PCRel<opc4, RawFrm, (outs), (ins brtarget:$dst), asm,
+                         [], IIC_Jcc>, OpSize16, TB;
+      def _4 : Ii32PCRel<opc4, RawFrm, (outs), (ins brtarget:$dst), asm,
+                         [], IIC_Jcc>, TB, OpSize32;
+    }
   }
 }
 
 defm JO  : ICBr<0x70, 0x80, "jo\t$dst" , X86_COND_O>;
-defm JNO : ICBr<0x71, 0x81, "jno\t$dst" , X86_COND_NO>;
+defm JNO : ICBr<0x71, 0x81, "jno\t$dst", X86_COND_NO>;
 defm JB  : ICBr<0x72, 0x82, "jb\t$dst" , X86_COND_B>;
 defm JAE : ICBr<0x73, 0x83, "jae\t$dst", X86_COND_AE>;
 defm JE  : ICBr<0x74, 0x84, "je\t$dst" , X86_COND_E>;
diff --git a/lib/Target/X86/X86InstrInfo.cpp b/lib/Target/X86/X86InstrInfo.cpp
index 3c8208a2c27..d643258b108 100644
--- a/lib/Target/X86/X86InstrInfo.cpp
+++ b/lib/Target/X86/X86InstrInfo.cpp
@@ -2723,22 +2723,22 @@ bool X86InstrInfo::findCommutedOpIndices(MachineInstr *MI, unsigned &SrcOpIdx1,
 static X86::CondCode getCondFromBranchOpc(unsigned BrOpc) {
   switch (BrOpc) {
   default: return X86::COND_INVALID;
-  case X86::JE_4:  return X86::COND_E;
-  case X86::JNE_4: return X86::COND_NE;
-  case X86::JL_4:  return X86::COND_L;
-  case X86::JLE_4: return X86::COND_LE;
-  case X86::JG_4:  return X86::COND_G;
-  case X86::JGE_4: return X86::COND_GE;
-  case X86::JB_4:  return X86::COND_B;
-  case X86::JBE_4: return X86::COND_BE;
-  case X86::JA_4:  return X86::COND_A;
-  case X86::JAE_4: return X86::COND_AE;
-  case X86::JS_4:  return X86::COND_S;
-  case X86::JNS_4: return X86::COND_NS;
-  case X86::JP_4:  return X86::COND_P;
-  case X86::JNP_4: return X86::COND_NP;
-  case X86::JO_4:  return X86::COND_O;
-  case X86::JNO_4: return X86::COND_NO;
+  case X86::JE_1:  return X86::COND_E;
+  case X86::JNE_1: return X86::COND_NE;
+  case X86::JL_1:  return X86::COND_L;
+  case X86::JLE_1: return X86::COND_LE;
+  case X86::JG_1:  return X86::COND_G;
+  case X86::JGE_1: return X86::COND_GE;
+  case X86::JB_1:  return X86::COND_B;
+  case X86::JBE_1: return X86::COND_BE;
+  case X86::JA_1:  return X86::COND_A;
+  case X86::JAE_1: return X86::COND_AE;
+  case X86::JS_1:  return X86::COND_S;
+  case X86::JNS_1: return X86::COND_NS;
+  case X86::JP_1:  return X86::COND_P;
+  case X86::JNP_1: return X86::COND_NP;
+  case X86::JO_1:  return X86::COND_O;
+  case X86::JNO_1: return X86::COND_NO;
   }
 }
 
@@ -2823,22 +2823,22 @@ X86::CondCode X86::getCondFromCMovOpc(unsigned Opc) {
 unsigned X86::GetCondBranchFromCond(X86::CondCode CC) {
   switch (CC) {
   default: llvm_unreachable("Illegal condition code!");
-  case X86::COND_E:  return X86::JE_4;
-  case X86::COND_NE: return X86::JNE_4;
-  case X86::COND_L:  return X86::JL_4;
-  case X86::COND_LE: return X86::JLE_4;
-  case X86::COND_G:  return X86::JG_4;
-  case X86::COND_GE: return X86::JGE_4;
-  case X86::COND_B:  return X86::JB_4;
-  case X86::COND_BE: return X86::JBE_4;
-  case X86::COND_A:  return X86::JA_4;
-  case X86::COND_AE: return X86::JAE_4;
-  case X86::COND_S:  return X86::JS_4;
-  case X86::COND_NS: return X86::JNS_4;
-  case X86::COND_P:  return X86::JP_4;
-  case X86::COND_NP: return X86::JNP_4;
-  case X86::COND_O:  return X86::JO_4;
-  case X86::COND_NO: return X86::JNO_4;
+  case X86::COND_E:  return X86::JE_1;
+  case X86::COND_NE: return X86::JNE_1;
+  case X86::COND_L:  return X86::JL_1;
+  case X86::COND_LE: return X86::JLE_1;
+  case X86::COND_G:  return X86::JG_1;
+  case X86::COND_GE: return X86::JGE_1;
+  case X86::COND_B:  return X86::JB_1;
+  case X86::COND_BE: return X86::JBE_1;
+  case X86::COND_A:  return X86::JA_1;
+  case X86::COND_AE: return X86::JAE_1;
+  case X86::COND_S:  return X86::JS_1;
+  case X86::COND_NS: return X86::JNS_1;
+  case X86::COND_P:  return X86::JP_1;
+  case X86::COND_NP: return X86::JNP_1;
+  case X86::COND_O:  return X86::JO_1;
+  case X86::COND_NO: return X86::JNO_1;
   }
 }
 
@@ -2996,7 +2996,7 @@ bool X86InstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,
       return true;
 
     // Handle unconditional branches.
-    if (I->getOpcode() == X86::JMP_4) {
+    if (I->getOpcode() == X86::JMP_1) {
       UnCondBrIter = I;
 
       if (!AllowModify) {
@@ -3058,7 +3058,7 @@ bool X86InstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,
 
         BuildMI(MBB, UnCondBrIter, MBB.findDebugLoc(I), get(JNCC))
           .addMBB(UnCondBrIter->getOperand(0).getMBB());
-        BuildMI(MBB, UnCondBrIter, MBB.findDebugLoc(I), get(X86::JMP_4))
+        BuildMI(MBB, UnCondBrIter, MBB.findDebugLoc(I), get(X86::JMP_1))
           .addMBB(TargetBB);
 
         OldInst->eraseFromParent();
@@ -3123,7 +3123,7 @@ unsigned X86InstrInfo::RemoveBranch(MachineBasicBlock &MBB) const {
     --I;
     if (I->isDebugValue())
       continue;
-    if (I->getOpcode() != X86::JMP_4 &&
+    if (I->getOpcode() != X86::JMP_1 &&
         getCondFromBranchOpc(I->getOpcode()) == X86::COND_INVALID)
       break;
     // Remove the branch.
@@ -3148,7 +3148,7 @@ X86InstrInfo::InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
   if (Cond.empty()) {
     // Unconditional branch?
     assert(!FBB && "Unconditional branch with multiple successors!");
-    BuildMI(&MBB, DL, get(X86::JMP_4)).addMBB(TBB);
+    BuildMI(&MBB, DL, get(X86::JMP_1)).addMBB(TBB);
     return 1;
   }
 
@@ -3158,16 +3158,16 @@ X86InstrInfo::InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
   switch (CC) {
   case X86::COND_NP_OR_E:
     // Synthesize NP_OR_E with two branches.
-    BuildMI(&MBB, DL, get(X86::JNP_4)).addMBB(TBB);
+    BuildMI(&MBB, DL, get(X86::JNP_1)).addMBB(TBB);
     ++Count;
-    BuildMI(&MBB, DL, get(X86::JE_4)).addMBB(TBB);
+    BuildMI(&MBB, DL, get(X86::JE_1)).addMBB(TBB);
     ++Count;
     break;
   case X86::COND_NE_OR_P:
     // Synthesize NE_OR_P with two branches.
-    BuildMI(&MBB, DL, get(X86::JNE_4)).addMBB(TBB);
+    BuildMI(&MBB, DL, get(X86::JNE_1)).addMBB(TBB);
     ++Count;
-    BuildMI(&MBB, DL, get(X86::JP_4)).addMBB(TBB);
+    BuildMI(&MBB, DL, get(X86::JP_1)).addMBB(TBB);
     ++Count;
     break;
   default: {
@@ -3178,7 +3178,7 @@ X86InstrInfo::InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
   }
   if (FBB) {
     // Two-way Conditional branch. Insert the second branch.
-    BuildMI(&MBB, DL, get(X86::JMP_4)).addMBB(FBB);
+    BuildMI(&MBB, DL, get(X86::JMP_1)).addMBB(FBB);
     ++Count;
   }
   return Count;
@@ -5344,26 +5344,26 @@ bool X86InstrInfo::shouldScheduleAdjacent(MachineInstr* First,
   switch(Second->getOpcode()) {
   default:
     return false;
-  case X86::JE_4:
-  case X86::JNE_4:
-  case X86::JL_4:
-  case X86::JLE_4:
-  case X86::JG_4:
-  case X86::JGE_4:
+  case X86::JE_1:
+  case X86::JNE_1:
+  case X86::JL_1:
+  case X86::JLE_1:
+  case X86::JG_1:
+  case X86::JGE_1:
     FuseKind = FuseInc;
     break;
-  case X86::JB_4:
-  case X86::JBE_4:
-  case X86::JA_4:
-  case X86::JAE_4:
+  case X86::JB_1:
+  case X86::JBE_1:
+  case X86::JA_1:
+  case X86::JAE_1:
     FuseKind = FuseCmp;
     break;
-  case X86::JS_4:
-  case X86::JNS_4:
-  case X86::JP_4:
-  case X86::JNP_4:
-  case X86::JO_4:
-  case X86::JNO_4:
+  case X86::JS_1:
+  case X86::JNS_1:
+  case X86::JP_1:
+  case X86::JNP_1:
+  case X86::JO_1:
+  case X86::JNO_1:
     FuseKind = FuseTest;
     break;
   }
@@ -5652,7 +5652,7 @@ void X86InstrInfo::getNoopForMachoTarget(MCInst &NopInst) const {
 // getUnconditionalBranch and getTrap.
 void X86InstrInfo::getUnconditionalBranch(
     MCInst &Branch, const MCSymbolRefExpr *BranchTarget) const {
-  Branch.setOpcode(X86::JMP_4);
+  Branch.setOpcode(X86::JMP_1);
   Branch.addOperand(MCOperand::CreateExpr(BranchTarget));
 }
 
diff --git a/lib/Target/X86/X86MCInstLower.cpp b/lib/Target/X86/X86MCInstLower.cpp
index 9d9bb084719..759416d6124 100644
--- a/lib/Target/X86/X86MCInstLower.cpp
+++ b/lib/Target/X86/X86MCInstLower.cpp
@@ -558,28 +558,6 @@ ReSimplify:
   case X86::ADD32ri8_DB:  OutMI.setOpcode(X86::OR32ri8); goto ReSimplify;
   case X86::ADD64ri8_DB:  OutMI.setOpcode(X86::OR64ri8); goto ReSimplify;
 
-  // The assembler backend wants to see branches in their small form and relax
-  // them to their large form.  The JIT can only handle the large form because
-  // it does not do relaxation.  For now, translate the large form to the
-  // small one here.
-  case X86::JMP_4: OutMI.setOpcode(X86::JMP_1); break;
-  case X86::JO_4:  OutMI.setOpcode(X86::JO_1); break;
-  case X86::JNO_4: OutMI.setOpcode(X86::JNO_1); break;
-  case X86::JB_4:  OutMI.setOpcode(X86::JB_1); break;
-  case X86::JAE_4: OutMI.setOpcode(X86::JAE_1); break;
-  case X86::JE_4:  OutMI.setOpcode(X86::JE_1); break;
-  case X86::JNE_4: OutMI.setOpcode(X86::JNE_1); break;
-  case X86::JBE_4: OutMI.setOpcode(X86::JBE_1); break;
-  case X86::JA_4:  OutMI.setOpcode(X86::JA_1); break;
-  case X86::JS_4:  OutMI.setOpcode(X86::JS_1); break;
-  case X86::JNS_4: OutMI.setOpcode(X86::JNS_1); break;
-  case X86::JP_4:  OutMI.setOpcode(X86::JP_1); break;
-  case X86::JNP_4: OutMI.setOpcode(X86::JNP_1); break;
-  case X86::JL_4:  OutMI.setOpcode(X86::JL_1); break;
-  case X86::JGE_4: OutMI.setOpcode(X86::JGE_1); break;
-  case X86::JLE_4: OutMI.setOpcode(X86::JLE_1); break;
-  case X86::JG_4:  OutMI.setOpcode(X86::JG_1); break;
-
   // Atomic load and store require a separate pseudo-inst because Acquire
   // implies mayStore and Release implies mayLoad; fix these to regular MOV
   // instructions here