Change SMRange to be half-open (exclusive end) instead of closed (inclusive)

This is necessary not only for representing empty ranges, but for handling
multibyte characters in the input. (If the end pointer in a range refers to
a multibyte character, should it point to the beginning or the end of the
character in a char array?) Some of the code in the asm parsers was already
assuming this anyway.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171765 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 90 insertions, 82 deletions

diff --git a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
index a836731124..ad37a21db7 100644
--- a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
+++ b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
@@ -178,7 +178,8 @@ class ARMAsmParser : public MCTargetAsmParser {
   OperandMatchResultTy parseAM3Offset(SmallVectorImpl<MCParsedAsmOperand*>&);
   OperandMatchResultTy parseFPImm(SmallVectorImpl<MCParsedAsmOperand*>&);
   OperandMatchResultTy parseVectorList(SmallVectorImpl<MCParsedAsmOperand*>&);
-  OperandMatchResultTy parseVectorLane(VectorLaneTy &LaneKind, unsigned &Index);
+  OperandMatchResultTy parseVectorLane(VectorLaneTy &LaneKind, unsigned &Index,
+                                       SMLoc &EndLoc);
 
   // Asm Match Converter Methods
   void cvtT2LdrdPre(MCInst &Inst, const SmallVectorImpl<MCParsedAsmOperand*> &);
@@ -2450,8 +2451,8 @@ static unsigned MatchRegisterName(StringRef Name);
 bool ARMAsmParser::ParseRegister(unsigned &RegNo,
                                  SMLoc &StartLoc, SMLoc &EndLoc) {
   StartLoc = Parser.getTok().getLoc();
+  EndLoc = Parser.getTok().getEndLoc();
   RegNo = tryParseRegister();
-  EndLoc = Parser.getTok().getLoc();
 
   return (RegNo == (unsigned)-1);
 }
@@ -2540,6 +2541,8 @@ int ARMAsmParser::tryParseShiftRegister(
   if (!PrevOp->isReg())
     return Error(PrevOp->getStartLoc(), "shift must be of a register");
   int SrcReg = PrevOp->getReg();
+
+  SMLoc EndLoc;
   int64_t Imm = 0;
   int ShiftReg = 0;
   if (ShiftTy == ARM_AM::rrx) {
@@ -2554,7 +2557,7 @@ int ARMAsmParser::tryParseShiftRegister(
       Parser.Lex(); // Eat hash.
       SMLoc ImmLoc = Parser.getTok().getLoc();
       const MCExpr *ShiftExpr = 0;
-      if (getParser().ParseExpression(ShiftExpr)) {
+      if (getParser().ParseExpression(ShiftExpr, EndLoc)) {
         Error(ImmLoc, "invalid immediate shift value");
         return -1;
       }
@@ -2579,8 +2582,9 @@ int ARMAsmParser::tryParseShiftRegister(
       if (Imm == 0)
         ShiftTy = ARM_AM::lsl;
     } else if (Parser.getTok().is(AsmToken::Identifier)) {
-      ShiftReg = tryParseRegister();
       SMLoc L = Parser.getTok().getLoc();
+      EndLoc = Parser.getTok().getEndLoc();
+      ShiftReg = tryParseRegister();
       if (ShiftReg == -1) {
         Error (L, "expected immediate or register in shift operand");
         return -1;
@@ -2595,10 +2599,10 @@ int ARMAsmParser::tryParseShiftRegister(
   if (ShiftReg && ShiftTy != ARM_AM::rrx)
     Operands.push_back(ARMOperand::CreateShiftedRegister(ShiftTy, SrcReg,
                                                          ShiftReg, Imm,
-                                               S, Parser.getTok().getLoc()));
+                                                         S, EndLoc));
   else
     Operands.push_back(ARMOperand::CreateShiftedImmediate(ShiftTy, SrcReg, Imm,
-                                               S, Parser.getTok().getLoc()));
+                                                          S, EndLoc));
 
   return 0;
 }
@@ -2612,12 +2616,13 @@ int ARMAsmParser::tryParseShiftRegister(
 /// parse for a specific register type.
 bool ARMAsmParser::
 tryParseRegisterWithWriteBack(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
-  SMLoc S = Parser.getTok().getLoc();
+  const AsmToken &RegTok = Parser.getTok();
   int RegNo = tryParseRegister();
   if (RegNo == -1)
     return true;
 
-  Operands.push_back(ARMOperand::CreateReg(RegNo, S, Parser.getTok().getLoc()));
+  Operands.push_back(ARMOperand::CreateReg(RegNo, RegTok.getLoc(),
+                                           RegTok.getEndLoc()));
 
   const AsmToken &ExclaimTok = Parser.getTok();
   if (ExclaimTok.is(AsmToken::Exclaim)) {
@@ -2641,10 +2646,10 @@ tryParseRegisterWithWriteBack(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
     if (!MCE)
       return TokError("immediate value expected for vector index");
 
-    SMLoc E = Parser.getTok().getLoc();
     if (Parser.getTok().isNot(AsmToken::RBrac))
-      return Error(E, "']' expected");
+      return Error(Parser.getTok().getLoc(), "']' expected");
 
+    SMLoc E = Parser.getTok().getEndLoc();
     Parser.Lex(); // Eat right bracket token.
 
     Operands.push_back(ARMOperand::CreateVectorIndex(MCE->getValue(),
@@ -2794,7 +2799,7 @@ parseCoprocOptionOperand(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
   // Check for and consume the closing '}'
   if (Parser.getTok().isNot(AsmToken::RCurly))
     return MatchOperand_ParseFail;
-  SMLoc E = Parser.getTok().getLoc();
+  SMLoc E = Parser.getTok().getEndLoc();
   Parser.Lex(); // Eat the '}'
 
   Operands.push_back(ARMOperand::CreateCoprocOption(Val, S, E));
@@ -2891,10 +2896,10 @@ parseRegisterList(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
          Parser.getTok().is(AsmToken::Minus)) {
     if (Parser.getTok().is(AsmToken::Minus)) {
       Parser.Lex(); // Eat the minus.
-      SMLoc EndLoc = Parser.getTok().getLoc();
+      SMLoc AfterMinusLoc = Parser.getTok().getLoc();
       int EndReg = tryParseRegister();
       if (EndReg == -1)
-        return Error(EndLoc, "register expected");
+        return Error(AfterMinusLoc, "register expected");
       // Allow Q regs and just interpret them as the two D sub-registers.
       if (ARMMCRegisterClasses[ARM::QPRRegClassID].contains(EndReg))
         EndReg = getDRegFromQReg(EndReg) + 1;
@@ -2904,10 +2909,10 @@ parseRegisterList(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
         continue;
       // The register must be in the same register class as the first.
       if (!RC->contains(EndReg))
-        return Error(EndLoc, "invalid register in register list");
+        return Error(AfterMinusLoc, "invalid register in register list");
       // Ranges must go from low to high.
       if (MRI->getEncodingValue(Reg) > MRI->getEncodingValue(EndReg))
-        return Error(EndLoc, "bad range in register list");
+        return Error(AfterMinusLoc, "bad range in register list");
 
       // Add all the registers in the range to the register list.
       while (Reg != EndReg) {
@@ -2955,9 +2960,9 @@ parseRegisterList(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
       Registers.push_back(std::pair<unsigned, SMLoc>(++Reg, RegLoc));
   }
 
-  SMLoc E = Parser.getTok().getLoc();
   if (Parser.getTok().isNot(AsmToken::RCurly))
-    return Error(E, "'}' expected");
+    return Error(Parser.getTok().getLoc(), "'}' expected");
+  SMLoc E = Parser.getTok().getEndLoc();
   Parser.Lex(); // Eat '}' token.
 
   // Push the register list operand.
@@ -2974,13 +2979,14 @@ parseRegisterList(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
 
 // Helper function to parse the lane index for vector lists.
 ARMAsmParser::OperandMatchResultTy ARMAsmParser::
-parseVectorLane(VectorLaneTy &LaneKind, unsigned &Index) {
+parseVectorLane(VectorLaneTy &LaneKind, unsigned &Index, SMLoc &EndLoc) {
   Index = 0; // Always return a defined index value.
   if (Parser.getTok().is(AsmToken::LBrac)) {
     Parser.Lex(); // Eat the '['.
     if (Parser.getTok().is(AsmToken::RBrac)) {
       // "Dn[]" is the 'all lanes' syntax.
       LaneKind = AllLanes;
+      EndLoc = Parser.getTok().getEndLoc();
       Parser.Lex(); // Eat the ']'.
       return MatchOperand_Success;
     }
@@ -3005,6 +3011,7 @@ parseVectorLane(VectorLaneTy &LaneKind, unsigned &Index) {
       Error(Parser.getTok().getLoc(), "']' expected");
       return MatchOperand_ParseFail;
     }
+    EndLoc = Parser.getTok().getEndLoc();
     Parser.Lex(); // Eat the ']'.
     int64_t Val = CE->getValue();
 
@@ -3031,21 +3038,19 @@ parseVectorList(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
   // (without encosing curly braces) as a single or double entry list,
   // respectively.
   if (Parser.getTok().is(AsmToken::Identifier)) {
+    SMLoc E = Parser.getTok().getEndLoc();
     int Reg = tryParseRegister();
     if (Reg == -1)
       return MatchOperand_NoMatch;
-    SMLoc E = Parser.getTok().getLoc();
     if (ARMMCRegisterClasses[ARM::DPRRegClassID].contains(Reg)) {
-      OperandMatchResultTy Res = parseVectorLane(LaneKind, LaneIndex);
+      OperandMatchResultTy Res = parseVectorLane(LaneKind, LaneIndex, E);
       if (Res != MatchOperand_Success)
         return Res;
       switch (LaneKind) {
       case NoLanes:
-        E = Parser.getTok().getLoc();
         Operands.push_back(ARMOperand::CreateVectorList(Reg, 1, false, S, E));
         break;
       case AllLanes:
-        E = Parser.getTok().getLoc();
         Operands.push_back(ARMOperand::CreateVectorListAllLanes(Reg, 1, false,
                                                                 S, E));
         break;
@@ -3059,18 +3064,16 @@ parseVectorList(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
     }
     if (ARMMCRegisterClasses[ARM::QPRRegClassID].contains(Reg)) {
       Reg = getDRegFromQReg(Reg);
-      OperandMatchResultTy Res = parseVectorLane(LaneKind, LaneIndex);
+      OperandMatchResultTy Res = parseVectorLane(LaneKind, LaneIndex, E);
       if (Res != MatchOperand_Success)
         return Res;
       switch (LaneKind) {
       case NoLanes:
-        E = Parser.getTok().getLoc();
         Reg = MRI->getMatchingSuperReg(Reg, ARM::dsub_0,
                                    &ARMMCRegisterClasses[ARM::DPairRegClassID]);
         Operands.push_back(ARMOperand::CreateVectorList(Reg, 2, false, S, E));
         break;
       case AllLanes:
-        E = Parser.getTok().getLoc();
         Reg = MRI->getMatchingSuperReg(Reg, ARM::dsub_0,
                                    &ARMMCRegisterClasses[ARM::DPairRegClassID]);
         Operands.push_back(ARMOperand::CreateVectorListAllLanes(Reg, 2, false,
@@ -3111,7 +3114,9 @@ parseVectorList(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
     ++Reg;
     ++Count;
   }
-  if (parseVectorLane(LaneKind, LaneIndex) != MatchOperand_Success)
+
+  SMLoc E;
+  if (parseVectorLane(LaneKind, LaneIndex, E) != MatchOperand_Success)
     return MatchOperand_ParseFail;
 
   while (Parser.getTok().is(AsmToken::Comma) ||
@@ -3125,10 +3130,10 @@ parseVectorList(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
         return MatchOperand_ParseFail;
       }
       Parser.Lex(); // Eat the minus.
-      SMLoc EndLoc = Parser.getTok().getLoc();
+      SMLoc AfterMinusLoc = Parser.getTok().getLoc();
       int EndReg = tryParseRegister();
       if (EndReg == -1) {
-        Error(EndLoc, "register expected");
+        Error(AfterMinusLoc, "register expected");
         return MatchOperand_ParseFail;
       }
       // Allow Q regs and just interpret them as the two D sub-registers.
@@ -3140,24 +3145,24 @@ parseVectorList(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
         continue;
       // The register must be in the same register class as the first.
       if (!ARMMCRegisterClasses[ARM::DPRRegClassID].contains(EndReg)) {
-        Error(EndLoc, "invalid register in register list");
+        Error(AfterMinusLoc, "invalid register in register list");
         return MatchOperand_ParseFail;
       }
       // Ranges must go from low to high.
       if (Reg > EndReg) {
-        Error(EndLoc, "bad range in register list");
+        Error(AfterMinusLoc, "bad range in register list");
         return MatchOperand_ParseFail;
       }
       // Parse the lane specifier if present.
       VectorLaneTy NextLaneKind;
       unsigned NextLaneIndex;
-      if (parseVectorLane(NextLaneKind, NextLaneIndex) != MatchOperand_Success)
+      if (parseVectorLane(NextLaneKind, NextLaneIndex, E) !=
+          MatchOperand_Success)
         return MatchOperand_ParseFail;
       if (NextLaneKind != LaneKind || LaneIndex != NextLaneIndex) {
-        Error(EndLoc, "mismatched lane index in register list");
+        Error(AfterMinusLoc, "mismatched lane index in register list");
         return MatchOperand_ParseFail;
       }
-      EndLoc = Parser.getTok().getLoc();
 
       // Add all the registers in the range to the register list.
       Count += EndReg - Reg;
@@ -3196,11 +3201,12 @@ parseVectorList(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
       // Parse the lane specifier if present.
       VectorLaneTy NextLaneKind;
       unsigned NextLaneIndex;
-      SMLoc EndLoc = Parser.getTok().getLoc();
-      if (parseVectorLane(NextLaneKind, NextLaneIndex) != MatchOperand_Success)
+      SMLoc LaneLoc = Parser.getTok().getLoc();
+      if (parseVectorLane(NextLaneKind, NextLaneIndex, E) !=
+          MatchOperand_Success)
         return MatchOperand_ParseFail;
       if (NextLaneKind != LaneKind || LaneIndex != NextLaneIndex) {
-        Error(EndLoc, "mismatched lane index in register list");
+        Error(LaneLoc, "mismatched lane index in register list");
         return MatchOperand_ParseFail;
       }
       continue;
@@ -3221,7 +3227,7 @@ parseVectorList(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
     VectorLaneTy NextLaneKind;
     unsigned NextLaneIndex;
     SMLoc EndLoc = Parser.getTok().getLoc();
-    if (parseVectorLane(NextLaneKind, NextLaneIndex) != MatchOperand_Success)
+    if (parseVectorLane(NextLaneKind, NextLaneIndex, E) != MatchOperand_Success)
       return MatchOperand_ParseFail;
     if (NextLaneKind != LaneKind || LaneIndex != NextLaneIndex) {
       Error(EndLoc, "mismatched lane index in register list");
@@ -3229,11 +3235,11 @@ parseVectorList(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
     }
   }
 
-  SMLoc E = Parser.getTok().getLoc();
   if (Parser.getTok().isNot(AsmToken::RCurly)) {
-    Error(E, "'}' expected");
+    Error(Parser.getTok().getLoc(), "'}' expected");
     return MatchOperand_ParseFail;
   }
+  E = Parser.getTok().getEndLoc();
   Parser.Lex(); // Eat '}' token.
 
   switch (LaneKind) {
@@ -3525,7 +3531,8 @@ parsePKHImm(SmallVectorImpl<MCParsedAsmOperand*> &Operands, StringRef Op,
 
   const MCExpr *ShiftAmount;
   SMLoc Loc = Parser.getTok().getLoc();
-  if (getParser().ParseExpression(ShiftAmount)) {
+  SMLoc EndLoc;
+  if (getParser().ParseExpression(ShiftAmount, EndLoc)) {
     Error(Loc, "illegal expression");
     return MatchOperand_ParseFail;
   }
@@ -3540,7 +3547,7 @@ parsePKHImm(SmallVectorImpl<MCParsedAsmOperand*> &Operands, StringRef Op,
     return MatchOperand_ParseFail;
   }
 
-  Operands.push_back(ARMOperand::CreateImm(CE, Loc, Parser.getTok().getLoc()));
+  Operands.push_back(ARMOperand::CreateImm(CE, Loc, EndLoc));
 
   return MatchOperand_Success;
 }
@@ -3550,7 +3557,7 @@ parseSetEndImm(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
   const AsmToken &Tok = Parser.getTok();
   SMLoc S = Tok.getLoc();
   if (Tok.isNot(AsmToken::Identifier)) {
-    Error(Tok.getLoc(), "'be' or 'le' operand expected");
+    Error(S, "'be' or 'le' operand expected");
     return MatchOperand_ParseFail;
   }
   int Val = StringSwitch<int>(Tok.getString())
@@ -3560,12 +3567,12 @@ parseSetEndImm(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
   Parser.Lex(); // Eat the token.
 
   if (Val == -1) {
-    Error(Tok.getLoc(), "'be' or 'le' operand expected");
+    Error(S, "'be' or 'le' operand expected");
     return MatchOperand_ParseFail;
   }
   Operands.push_back(ARMOperand::CreateImm(MCConstantExpr::Create(Val,
                                                                   getContext()),
-                                           S, Parser.getTok().getLoc()));
+                                           S, Tok.getEndLoc()));
   return MatchOperand_Success;
 }
 
@@ -3601,16 +3608,17 @@ parseShifterImm(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
     return MatchOperand_ParseFail;
   }
   Parser.Lex(); // Eat hash token.
+  SMLoc ExLoc = Parser.getTok().getLoc();
 
   const MCExpr *ShiftAmount;
-  SMLoc E = Parser.getTok().getLoc();
-  if (getParser().ParseExpression(ShiftAmount)) {
-    Error(E, "malformed shift expression");
+  SMLoc EndLoc;
+  if (getParser().ParseExpression(ShiftAmount, EndLoc)) {
+    Error(ExLoc, "malformed shift expression");
     return MatchOperand_ParseFail;
   }
   const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(ShiftAmount);
   if (!CE) {
-    Error(E, "shift amount must be an immediate");
+    Error(ExLoc, "shift amount must be an immediate");
     return MatchOperand_ParseFail;
   }
 
@@ -3618,25 +3626,24 @@ parseShifterImm(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
   if (isASR) {
     // Shift amount must be in [1,32]
     if (Val < 1 || Val > 32) {
-      Error(E, "'asr' shift amount must be in range [1,32]");
+      Error(ExLoc, "'asr' shift amount must be in range [1,32]");
       return MatchOperand_ParseFail;
     }
     // asr #32 encoded as asr #0, but is not allowed in Thumb2 mode.
     if (isThumb() && Val == 32) {
-      Error(E, "'asr #32' shift amount not allowed in Thumb mode");
+      Error(ExLoc, "'asr #32' shift amount not allowed in Thumb mode");
       return MatchOperand_ParseFail;
     }
     if (Val == 32) Val = 0;
   } else {
     // Shift amount must be in [1,32]
     if (Val < 0 || Val > 31) {
-      Error(E, "'lsr' shift amount must be in range [0,31]");
+      Error(ExLoc, "'lsr' shift amount must be in range [0,31]");
       return MatchOperand_ParseFail;
     }
   }
 
-  E = Parser.getTok().getLoc();
-  Operands.push_back(ARMOperand::CreateShifterImm(isASR, Val, S, E));
+  Operands.push_back(ARMOperand::CreateShifterImm(isASR, Val, S, EndLoc));
 
   return MatchOperand_Success;
 }
@@ -3662,16 +3669,17 @@ parseRotImm(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
     return MatchOperand_ParseFail;
   }
   Parser.Lex(); // Eat hash token.
+  SMLoc ExLoc = Parser.getTok().getLoc();
 
   const MCExpr *ShiftAmount;
-  SMLoc E = Parser.getTok().getLoc();
-  if (getParser().ParseExpression(ShiftAmount)) {
-    Error(E, "malformed rotate expression");
+  SMLoc EndLoc;
+  if (getParser().ParseExpression(ShiftAmount, EndLoc)) {
+    Error(ExLoc, "malformed rotate expression");
     return MatchOperand_ParseFail;
   }
   const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(ShiftAmount);
   if (!CE) {
-    Error(E, "rotate amount must be an immediate");
+    Error(ExLoc, "rotate amount must be an immediate");
     return MatchOperand_ParseFail;
   }
 
@@ -3680,12 +3688,11 @@ parseRotImm(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
   // normally, zero is represented in asm by omitting the rotate operand
   // entirely.
   if (Val != 8 && Val != 16 && Val != 24 && Val != 0) {
-    Error(E, "'ror' rotate amount must be 8, 16, or 24");
+    Error(ExLoc, "'ror' rotate amount must be 8, 16, or 24");
     return MatchOperand_ParseFail;
   }
 
-  E = Parser.getTok().getLoc();
-  Operands.push_back(ARMOperand::CreateRotImm(Val, S, E));
+  Operands.push_back(ARMOperand::CreateRotImm(Val, S, EndLoc));
 
   return MatchOperand_Success;
 }
@@ -3735,7 +3742,8 @@ parseBitfield(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
   Parser.Lex(); // Eat hash token.
 
   const MCExpr *WidthExpr;
-  if (getParser().ParseExpression(WidthExpr)) {
+  SMLoc EndLoc;
+  if (getParser().ParseExpression(WidthExpr, EndLoc)) {
     Error(E, "malformed immediate expression");
     return MatchOperand_ParseFail;
   }
@@ -3751,9 +3759,8 @@ parseBitfield(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
     Error(E, "'width' operand must be in the range [1,32-lsb]");
     return MatchOperand_ParseFail;
   }
-  E = Parser.getTok().getLoc();
 
-  Operands.push_back(ARMOperand::CreateBitfield(LSB, Width, S, E));
+  Operands.push_back(ARMOperand::CreateBitfield(LSB, Width, S, EndLoc));
 
   return MatchOperand_Success;
 }
@@ -3772,7 +3779,6 @@ parsePostIdxReg(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
   SMLoc S = Tok.getLoc();
   bool haveEaten = false;
   bool isAdd = true;
-  int Reg = -1;
   if (Tok.is(AsmToken::Plus)) {
     Parser.Lex(); // Eat the '+' token.
     haveEaten = true;
@@ -3781,15 +3787,15 @@ parsePostIdxReg(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
     isAdd = false;
     haveEaten = true;
   }
-  if (Parser.getTok().is(AsmToken::Identifier))
-    Reg = tryParseRegister();
+
+  SMLoc E = Parser.getTok().getEndLoc();
+  int Reg = tryParseRegister();
   if (Reg == -1) {
     if (!haveEaten)
       return MatchOperand_NoMatch;
     Error(Parser.getTok().getLoc(), "register expected");
     return MatchOperand_ParseFail;
   }
-  SMLoc E = Parser.getTok().getLoc();
 
   ARM_AM::ShiftOpc ShiftTy = ARM_AM::no_shift;
   unsigned ShiftImm = 0;
@@ -3797,6 +3803,9 @@ parsePostIdxReg(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
     Parser.Lex(); // Eat the ','.
     if (parseMemRegOffsetShift(ShiftTy, ShiftImm))
       return MatchOperand_ParseFail;
+
+    // FIXME: Only approximates end...may include intervening whitespace.
+    E = Parser.getTok().getLoc();
   }
 
   Operands.push_back(ARMOperand::CreatePostIdxReg(Reg, isAdd, ShiftTy,
@@ -3829,14 +3838,14 @@ parseAM3Offset(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
     // differently.
     bool isNegative = Parser.getTok().is(AsmToken::Minus);
     const MCExpr *Offset;
-    if (getParser().ParseExpression(Offset))
+    SMLoc E;
+    if (getParser().ParseExpression(Offset, E))
       return MatchOperand_ParseFail;
     const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(Offset);
     if (!CE) {
       Error(S, "constant expression expected");
       return MatchOperand_ParseFail;
     }
-    SMLoc E = Tok.getLoc();
     // Negative zero is encoded as the flag value INT32_MIN.
     int32_t Val = CE->getValue();
     if (isNegative && Val == 0)
@@ -3851,7 +3860,6 @@ parseAM3Offset(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
 
   bool haveEaten = false;
   bool isAdd = true;
-  int Reg = -1;
   if (Tok.is(AsmToken::Plus)) {
     Parser.Lex(); // Eat the '+' token.
     haveEaten = true;
@@ -3860,18 +3868,18 @@ parseAM3Offset(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
     isAdd = false;
     haveEaten = true;
   }
-  if (Parser.getTok().is(AsmToken::Identifier))
-    Reg = tryParseRegister();
+  
+  Tok = Parser.getTok();
+  int Reg = tryParseRegister();
   if (Reg == -1) {
     if (!haveEaten)
       return MatchOperand_NoMatch;
-    Error(Parser.getTok().getLoc(), "register expected");
+    Error(Tok.getLoc(), "register expected");
     return MatchOperand_ParseFail;
   }
-  SMLoc E = Parser.getTok().getLoc();
 
   Operands.push_back(ARMOperand::CreatePostIdxReg(Reg, isAdd, ARM_AM::no_shift,
-                                                  0, S, E));
+                                                  0, S, Tok.getEndLoc()));
 
   return MatchOperand_Success;
 }
@@ -4224,7 +4232,7 @@ parseMemory(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
     return Error(Tok.getLoc(), "malformed memory operand");
 
   if (Tok.is(AsmToken::RBrac)) {
-    E = Tok.getLoc();
+    E = Tok.getEndLoc();
     Parser.Lex(); // Eat right bracket token.
 
     Operands.push_back(ARMOperand::CreateMem(BaseRegNum, 0, 0, ARM_AM::no_shift,
@@ -4272,9 +4280,9 @@ parseMemory(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
     }
 
     // Now we should have the closing ']'
-    E = Parser.getTok().getLoc();
     if (Parser.getTok().isNot(AsmToken::RBrac))
-      return Error(E, "']' expected");
+      return Error(Parser.getTok().getLoc(), "']' expected");
+    E = Parser.getTok().getEndLoc();
     Parser.Lex(); // Eat right bracket token.
 
     // Don't worry about range checking the value here. That's handled by
@@ -4321,9 +4329,9 @@ parseMemory(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
       CE = MCConstantExpr::Create(INT32_MIN, getContext());
 
     // Now we should have the closing ']'
-    E = Parser.getTok().getLoc();
     if (Parser.getTok().isNot(AsmToken::RBrac))
-      return Error(E, "']' expected");
+      return Error(Parser.getTok().getLoc(), "']' expected");
+    E = Parser.getTok().getEndLoc();
     Parser.Lex(); // Eat right bracket token.
 
     // Don't worry about range checking the value here. That's handled by
@@ -4367,9 +4375,9 @@ parseMemory(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
   }
 
   // Now we should have the closing ']'
-  E = Parser.getTok().getLoc();
   if (Parser.getTok().isNot(AsmToken::RBrac))
-    return Error(E, "']' expected");
+    return Error(Parser.getTok().getLoc(), "']' expected");
+  E = Parser.getTok().getEndLoc();
   Parser.Lex(); // Eat right bracket token.
 
   Operands.push_back(ARMOperand::CreateMem(BaseRegNum, 0, OffsetRegNum,