diff --git a/lib/Target/ARM/Disassembler/ThumbDisassemblerCore.h b/lib/Target/ARM/Disassembler/ThumbDisassemblerCore.h
index 53efaa7d1f3..4b2e308248c 100644
--- a/lib/Target/ARM/Disassembler/ThumbDisassemblerCore.h
+++ b/lib/Target/ARM/Disassembler/ThumbDisassemblerCore.h
@@ -624,7 +624,7 @@ static bool DisassembleThumb1LdStSP(MCInst &MI, unsigned Opcode, uint32_t insn,
     unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
 
   assert((Opcode == ARM::tLDRspi || Opcode == ARM::tSTRspi)
-         && "Invalid opcode");
+         && "Unexpected opcode");
 
   const TargetOperandInfo *OpInfo = ARMInsts[Opcode].OpInfo;
   if (!OpInfo) return false;
@@ -652,7 +652,7 @@ static bool DisassembleThumb1LdStSP(MCInst &MI, unsigned Opcode, uint32_t insn,
 static bool DisassembleThumb1AddPCi(MCInst &MI, unsigned Opcode, uint32_t insn,
     unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
 
-  assert(Opcode == ARM::tADDrPCi && "Invalid opcode");
+  assert(Opcode == ARM::tADDrPCi && "Unexpected opcode");
 
   const TargetOperandInfo *OpInfo = ARMInsts[Opcode].OpInfo;
   if (!OpInfo) return false;
@@ -677,7 +677,7 @@ static bool DisassembleThumb1AddPCi(MCInst &MI, unsigned Opcode, uint32_t insn,
 static bool DisassembleThumb1AddSPi(MCInst &MI, unsigned Opcode, uint32_t insn,
     unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
 
-  assert(Opcode == ARM::tADDrSPi && "Invalid opcode");
+  assert(Opcode == ARM::tADDrSPi && "Unexpected opcode");
 
   const TargetOperandInfo *OpInfo = ARMInsts[Opcode].OpInfo;
   if (!OpInfo) return false;
@@ -708,7 +708,7 @@ static bool DisassembleThumb1AddSPi(MCInst &MI, unsigned Opcode, uint32_t insn,
 static bool DisassembleThumb1PushPop(MCInst &MI, unsigned Opcode, uint32_t insn,
     unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
 
-  assert((Opcode == ARM::tPUSH || Opcode == ARM::tPOP) && "Invalid opcode");
+  assert((Opcode == ARM::tPUSH || Opcode == ARM::tPOP) && "Unexpected opcode");
 
   unsigned &OpIdx = NumOpsAdded;
 
@@ -821,7 +821,7 @@ static bool DisassembleThumb1Misc(MCInst &MI, unsigned Opcode, uint32_t insn,
                                                        getT1tRn(insn))));
   } else {
     // CBNZ, CBZ
-    assert((Opcode == ARM::tCBNZ || Opcode == ARM::tCBZ) && "Invalid opcode");
+    assert((Opcode == ARM::tCBNZ || Opcode == ARM::tCBZ) &&"Unexpected opcode");
     MI.addOperand(MCOperand::CreateImm(getT1Imm6(insn) * 2));
   }
 
@@ -839,7 +839,7 @@ static bool DisassembleThumb1LdStMul(bool Ld, MCInst &MI, unsigned Opcode,
     uint32_t insn, unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
 
   assert((Opcode == ARM::tLDM || Opcode == ARM::tLDM_UPD ||
-          Opcode == ARM::tSTM_UPD) && "Invalid opcode");
+          Opcode == ARM::tSTM_UPD) && "Unexpected opcode");
 
   unsigned &OpIdx = NumOpsAdded;
 
@@ -1123,7 +1123,7 @@ static bool DisassembleThumb2LdStMul(MCInst &MI, unsigned Opcode, uint32_t insn,
 
   assert((Opcode == ARM::t2LDM || Opcode == ARM::t2LDM_UPD ||
           Opcode == ARM::t2STM || Opcode == ARM::t2STM_UPD)
-         && "Invalid opcode");
+         && "Unexpected opcode");
   assert(NumOps >= 5 && "Thumb2 LdStMul expects NumOps >= 5");
 
   unsigned &OpIdx = NumOpsAdded;
@@ -1363,7 +1363,7 @@ static bool DisassembleThumb2DPSoReg(MCInst &MI, unsigned Opcode, uint32_t insn,
                                                          decodeRn(insn))));
       ++OpIdx;
     } else {
-      DEBUG(errs() << "Thumb encoding error: d==15 for three-reg operands.\n");
+      DEBUG(errs() << "Thumb2 encoding error: d==15 for three-reg operands.\n");
       return false;
     }
   }
@@ -1431,7 +1431,7 @@ static bool DisassembleThumb2DPModImm(MCInst &MI, unsigned Opcode,
 
   if (TwoReg) {
     if (NoDstReg) {
-      DEBUG(errs() << "Thumb encoding error: d==15 for DPModImm 2-reg instr.\n");
+      DEBUG(errs()<<"Thumb2 encoding error: d==15 for DPModImm 2-reg instr.\n");
       return false;
     }
     MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
@@ -1476,7 +1476,7 @@ static inline unsigned decodeThumb2SaturatePos(unsigned Opcode, uint32_t insn) {
   case ARM::t2USAT16:
     return slice(insn, 3, 0);
   default:
-    assert(0 && "Invalid opcode passed in");
+    assert(0 && "Unexpected opcode");
     return 0;
   }
 }
@@ -1576,7 +1576,7 @@ static bool DisassembleThumb2DPBinImm(MCInst &MI, unsigned Opcode,
   } else {
     // Handle the case of: lsb width
     assert((Opcode == ARM::t2SBFX || Opcode == ARM::t2UBFX ||
-            Opcode == ARM::t2BFI) && "Invalid opcode");
+            Opcode == ARM::t2BFI) && "Unexpected opcode");
     MI.addOperand(MCOperand::CreateImm(getLsb(insn)));
     if (Opcode == ARM::t2BFI) {
       if (getMsb(insn) < getLsb(insn)) {
@@ -1705,7 +1705,7 @@ static bool DisassembleThumb2BrMiscCtrl(MCInst &MI, unsigned Opcode,
 
   switch (Opcode) {
   default:
-    assert(0 && "Unreachable code");
+    assert(0 && "Unexpected opcode");
     return false;
   case ARM::t2B:
     Offset = decodeImm32_B_EncodingT4(insn);
@@ -2122,7 +2122,7 @@ static bool DisassembleThumb2(uint16_t op1, uint16_t op2, uint16_t op,
       }
 
       // Load/store dual, load/store exclusive, table branch, otherwise.
-      assert(slice(op2, 2, 2) == 1 && "Encoding error");
+      assert(slice(op2, 2, 2) == 1 && "Thumb2 encoding error!");
       if ((ARM::t2LDREX <= Opcode && Opcode <= ARM::t2LDREXH) ||
           (ARM::t2STREX <= Opcode && Opcode <= ARM::t2STREXH)) {
         // Load/store exclusive.
@@ -2209,7 +2209,7 @@ static bool DisassembleThumb2(uint16_t op1, uint16_t op2, uint16_t op,
 
     break;
   default:
-    assert(0 && "Encoding error for Thumb2 instruction!");
+    assert(0 && "Thumb2 encoding error!");
     break;
   }