X86 Asm uses assertions instead of proper diagnostic. This patch fixes that.

Differential Revision: https://reviews.llvm.org/D35115

llvm-svn: 308972
diff --git a/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp b/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
index 30ea089..62dc948 100644
--- a/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
+++ b/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
@@ -37,6 +37,14 @@
 
 using namespace llvm;
 
+static bool checkScale(unsigned Scale, StringRef &ErrMsg) {
+  if (Scale != 1 && Scale != 2 && Scale != 4 && Scale != 8) {
+    ErrMsg = "scale factor in address must be 1, 2, 4 or 8";
+    return true;
+  }
+  return false;
+}
+
 namespace {
 
 static const char OpPrecedence[] = {
@@ -125,8 +133,8 @@
     int64_t popOperand() {
       assert (!PostfixStack.empty() && "Poped an empty stack!");
       ICToken Op = PostfixStack.pop_back_val();
-      assert ((Op.first == IC_IMM || Op.first == IC_REGISTER)
-              && "Expected and immediate or register!");
+      if (!(Op.first == IC_IMM || Op.first == IC_REGISTER))
+        return -1; // The invalid Scale value will be caught later by checkScale
       return Op.second;
     }
     void pushOperand(InfixCalculatorTok Op, int64_t Val = 0) {
@@ -422,7 +430,7 @@
       }
       PrevState = CurrState;
     }
-    void onPlus() {
+    bool onPlus(StringRef &ErrMsg) {
       IntelExprState CurrState = State;
       switch (State) {
       default:
@@ -439,7 +447,10 @@
           if (!BaseReg) {
             BaseReg = TmpReg;
           } else {
-            assert (!IndexReg && "BaseReg/IndexReg already set!");
+            if (IndexReg) {
+              ErrMsg = "BaseReg/IndexReg already set!";
+              return true;
+            }
             IndexReg = TmpReg;
             Scale = 1;
           }
@@ -447,8 +458,9 @@
         break;
       }
       PrevState = CurrState;
+      return false;
     }
-    void onMinus() {
+    bool onMinus(StringRef &ErrMsg) {
       IntelExprState CurrState = State;
       switch (State) {
       default:
@@ -475,7 +487,11 @@
         if (CurrState == IES_REGISTER || CurrState == IES_RPAREN ||
             CurrState == IES_INTEGER  || CurrState == IES_RBRAC)
           IC.pushOperator(IC_MINUS);
-        else
+        else if (PrevState == IES_REGISTER && CurrState == IES_MULTIPLY) {
+          // We have negate operator for Scale: it's illegal
+          ErrMsg = "Scale can't be negative";
+          return true;
+        } else
           IC.pushOperator(IC_NEG);
         if (CurrState == IES_REGISTER && PrevState != IES_MULTIPLY) {
           // If we already have a BaseReg, then assume this is the IndexReg with
@@ -483,7 +499,10 @@
           if (!BaseReg) {
             BaseReg = TmpReg;
           } else {
-            assert (!IndexReg && "BaseReg/IndexReg already set!");
+            if (IndexReg) {
+              ErrMsg = "BaseReg/IndexReg already set!";
+              return true;
+            }
             IndexReg = TmpReg;
             Scale = 1;
           }
@@ -491,6 +510,7 @@
         break;
       }
       PrevState = CurrState;
+      return false;
     }
     void onNot() {
       IntelExprState CurrState = State;
@@ -517,7 +537,8 @@
       }
       PrevState = CurrState;
     }
-    void onRegister(unsigned Reg) {
+
+    bool onRegister(unsigned Reg, StringRef &ErrMsg) {
       IntelExprState CurrState = State;
       switch (State) {
       default:
@@ -532,11 +553,16 @@
       case IES_MULTIPLY:
         // Index Register - Scale * Register
         if (PrevState == IES_INTEGER) {
-          assert (!IndexReg && "IndexReg already set!");
+          if (IndexReg) {
+            ErrMsg = "BaseReg/IndexReg already set!";
+            return true;
+          }
           State = IES_REGISTER;
           IndexReg = Reg;
           // Get the scale and replace the 'Scale * Register' with '0'.
           Scale = IC.popOperand();
+          if (checkScale(Scale, ErrMsg))
+            return true;
           IC.pushOperand(IC_IMM);
           IC.popOperator();
         } else {
@@ -545,6 +571,7 @@
         break;
       }
       PrevState = CurrState;
+      return false;
     }
     void onIdentifierExpr(const MCExpr *SymRef, StringRef SymRefName) {
       PrevState = State;
@@ -583,13 +610,14 @@
         State = IES_INTEGER;
         if (PrevState == IES_REGISTER && CurrState == IES_MULTIPLY) {
           // Index Register - Register * Scale
-          assert (!IndexReg && "IndexReg already set!");
-          IndexReg = TmpReg;
-          Scale = TmpInt;
-          if(Scale != 1 && Scale != 2 && Scale != 4 && Scale != 8) {
-            ErrMsg = "scale factor in address must be 1, 2, 4 or 8";
+          if (IndexReg) {
+            ErrMsg = "BaseReg/IndexReg already set!";
             return true;
           }
+          IndexReg = TmpReg;
+          Scale = TmpInt;
+          if (checkScale(Scale, ErrMsg))
+            return true;
           // Get the scale and replace the 'Register * Scale' with '0'.
           IC.popOperator();
         } else {
@@ -885,8 +913,8 @@
 
 /// }
 
-static bool CheckBaseRegAndIndexReg(unsigned BaseReg, unsigned IndexReg,
-                                    StringRef &ErrMsg) {
+static bool CheckBaseRegAndIndexRegAndScale(unsigned BaseReg, unsigned IndexReg,
+                                            unsigned Scale, StringRef &ErrMsg) {
   // If we have both a base register and an index register make sure they are
   // both 64-bit or 32-bit registers.
   // To support VSIB, IndexReg can be 128-bit or 256-bit registers.
@@ -925,7 +953,7 @@
       }
     }
   }
-  return false;
+  return checkScale(Scale, ErrMsg);
 }
 
 bool X86AsmParser::ParseRegister(unsigned &RegNo,
@@ -1348,6 +1376,7 @@
 bool X86AsmParser::ParseIntelExpression(IntelExprStateMachine &SM, SMLoc &End) {
   MCAsmParser &Parser = getParser();
   const AsmToken &Tok = Parser.getTok();
+  StringRef ErrMsg;
 
   AsmToken::TokenKind PrevTK = AsmToken::Error;
   bool Done = false;
@@ -1386,7 +1415,8 @@
       StringRef Identifier = Tok.getString();
       UpdateLocLex = false;
       if (TK != AsmToken::String && !ParseRegister(TmpReg, IdentLoc, End)) {
-        SM.onRegister(TmpReg);
+        if (SM.onRegister(TmpReg, ErrMsg))
+          return Error(Tok.getLoc(), ErrMsg);
       } else if (ParseIntelNamedOperator(Identifier, SM)) {
         UpdateLocLex = true;
       } else if (!isParsingInlineAsm()) {
@@ -1400,7 +1430,6 @@
         int64_t Val = ParseIntelOperator(OpKind,SM.getAddImmPrefix());
         if (!Val)
           return true;
-        StringRef ErrMsg;
         if (SM.onInteger(Val, ErrMsg))
           return Error(IdentLoc, ErrMsg);
       } else if (Identifier.find('.') != StringRef::npos &&
@@ -1443,7 +1472,6 @@
       break;
     }
     case AsmToken::Integer: {
-      StringRef ErrMsg;
       if (isParsingInlineAsm() && SM.getAddImmPrefix())
         InstInfo->AsmRewrites->emplace_back(AOK_ImmPrefix, Tok.getLoc());
       // Look for 'b' or 'f' following an Integer as a directional label
@@ -1474,8 +1502,14 @@
       }
       break;
     }
-    case AsmToken::Plus:    SM.onPlus(); break;
-    case AsmToken::Minus:   SM.onMinus(); break;
+    case AsmToken::Plus:
+      if (SM.onPlus(ErrMsg))
+        return Error(getTok().getLoc(), ErrMsg);
+      break;
+    case AsmToken::Minus:
+      if (SM.onMinus(ErrMsg))
+        return Error(getTok().getLoc(), ErrMsg);
+      break;
     case AsmToken::Tilde:   SM.onNot(); break;
     case AsmToken::Star:    SM.onStar(); break;
     case AsmToken::Slash:   SM.onDivide(); break;
@@ -1582,7 +1616,7 @@
                                    Start, End, Size);
     }
     StringRef ErrMsg;
-    if (CheckBaseRegAndIndexReg(BaseReg, IndexReg, ErrMsg)) {
+    if (CheckBaseRegAndIndexRegAndScale(BaseReg, IndexReg, Scale, ErrMsg)) {
       Error(StartInBrac, ErrMsg);
       return nullptr;
     }
@@ -2292,7 +2326,7 @@
   }
 
   StringRef ErrMsg;
-  if (CheckBaseRegAndIndexReg(BaseReg, IndexReg, ErrMsg)) {
+  if (CheckBaseRegAndIndexRegAndScale(BaseReg, IndexReg, Scale, ErrMsg)) {
     Error(BaseLoc, ErrMsg);
     return nullptr;
   }