[llvm] r300828 - [AArch64] Fix handling of integer fp immediates

[John Brawn via llvm-commits]

Author: john.brawn
Date: Thu Apr 20 05:10:10 2017
New Revision: 300828

URL: http://llvm.org/viewvc/llvm-project?rev=300828&view=rev
Log:
[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.

Modified:
    llvm/trunk/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp
    llvm/trunk/test/MC/AArch64/basic-a64-diagnostics.s

Modified: llvm/trunk/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp?rev=300828&r1=300827&r2=300828&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp (original)
+++ llvm/trunk/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp Thu Apr 20 05:10:10 2017
@@ -2100,27 +2100,9 @@ AArch64AsmParser::tryParseFPImm(OperandV
   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(OperandV
       }
     } 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()));

Modified: llvm/trunk/test/MC/AArch64/basic-a64-diagnostics.s
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/MC/AArch64/basic-a64-diagnostics.s?rev=300828&r1=300827&r2=300828&view=diff
==============================================================================
--- llvm/trunk/test/MC/AArch64/basic-a64-diagnostics.s (original)
+++ llvm/trunk/test/MC/AArch64/basic-a64-diagnostics.s Thu Apr 20 05:10:10 2017
@@ -1781,12 +1781,20 @@
         ;; Exponent too large
         fmov d3, #0.0625
         fmov s2, #32.0
+        fmov s2, #32
+        fmov v0.4s, #-32
 // CHECK-ERROR: error: expected compatible register or floating-point constant
 // CHECK-ERROR-NEXT:           fmov d3, #0.0625
 // CHECK-ERROR-NEXT:                    ^
 // CHECK-ERROR-NEXT: error: expected compatible register or floating-point constant
 // CHECK-ERROR-NEXT:           fmov s2, #32.0
 // CHECK-ERROR-NEXT:                    ^
+// CHECK-ERROR-NEXT: error: expected compatible register or floating-point constant
+// CHECK-ERROR-NEXT:           fmov s2, #32
+// CHECK-ERROR-NEXT:                    ^
+// CHECK-ERROR-NEXT: error: expected compatible register or floating-point constant
+// CHECK-ERROR-NEXT:           fmov v0.4s, #-32
+// CHECK-ERROR-NEXT:                       ^
 
         ;; Fraction too precise
         fmov s9, #1.03125
@@ -1798,6 +1806,12 @@
 // CHECK-ERROR-NEXT:           fmov s28, #1.96875
 // CHECK-ERROR-NEXT:                     ^
 
+        ;; Explicitly encoded value too large
+        fmov s15, #0x100
+// CHECK-ERROR: error: encoded floating point value out of range
+// CHECK-ERROR-NEXT:           fmov s15, #0x100
+// CHECK-ERROR-NEXT:                     ^
+
         ;; No particular reason, but a striking omission
         fmov d0, #0.0
 // CHECK-ERROR-AARCH64: error: expected compatible register or floating-point constant