[AArch64] Fix handling of integer fp immediates

When an integer is used as an fp immediate we're failing to check the return
value of getFP64Imm, so invalid values are silently permitted. Fix this by
merging together the integer and real handling.

llvm-svn: 300828

1 files changed, 13 insertions, 22 deletions

diff --git a/llvm/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp b/llvm/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp
index cbab68979c5..347cffe72c3 100644
--- a/llvm/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp
+++ b/llvm/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp
@@ -2100,27 +2100,9 @@ AArch64AsmParser::tryParseFPImm(OperandVector &Operands) {
   bool isNegative = parseOptionalToken(AsmToken::Minus);
 
   const AsmToken &Tok = Parser.getTok();
-  if (Tok.is(AsmToken::Real)) {
-    APFloat RealVal(APFloat::IEEEdouble(), Tok.getString());
-    if (isNegative)
-      RealVal.changeSign();
-
-    uint64_t IntVal = RealVal.bitcastToAPInt().getZExtValue();
-    int Val = AArch64_AM::getFP64Imm(APInt(64, IntVal));
-    Parser.Lex(); // Eat the token.
-    // Check for out of range values. As an exception, we let Zero through,
-    // as we handle that special case in post-processing before matching in
-    // order to use the zero register for it.
-    if (Val == -1 && !RealVal.isPosZero()) {
-      TokError("expected compatible register or floating-point constant");
-      return MatchOperand_ParseFail;
-    }
-    Operands.push_back(AArch64Operand::CreateFPImm(Val, S, getContext()));
-    return MatchOperand_Success;
-  }
-  if (Tok.is(AsmToken::Integer)) {
+  if (Tok.is(AsmToken::Real) || Tok.is(AsmToken::Integer)) {
     int64_t Val;
-    if (!isNegative && Tok.getString().startswith("0x")) {
+    if (Tok.is(AsmToken::Integer) && !isNegative && Tok.getString().startswith("0x")) {
       Val = Tok.getIntVal();
       if (Val > 255 || Val < 0) {
         TokError("encoded floating point value out of range");
@@ -2128,10 +2110,19 @@ AArch64AsmParser::tryParseFPImm(OperandVector &Operands) {
       }
     } else {
       APFloat RealVal(APFloat::IEEEdouble(), Tok.getString());
+      if (isNegative)
+        RealVal.changeSign();
+
       uint64_t IntVal = RealVal.bitcastToAPInt().getZExtValue();
-      // If we had a '-' in front, toggle the sign bit.
-      IntVal ^= (uint64_t)isNegative << 63;
       Val = AArch64_AM::getFP64Imm(APInt(64, IntVal));
+
+      // Check for out of range values. As an exception, we let Zero through,
+      // as we handle that special case in post-processing before matching in
+      // order to use the zero register for it.
+      if (Val == -1 && !RealVal.isPosZero()) {
+        TokError("expected compatible register or floating-point constant");
+        return MatchOperand_ParseFail;
+      }
     }
     Parser.Lex(); // Eat the token.
     Operands.push_back(AArch64Operand::CreateFPImm(Val, S, getContext()));