From f805a0cc2d8a8a53b81c9ce0afe1c008e9da4872 Mon Sep 17 00:00:00 2001
From: John Brawn <john.brawn@arm.com>
Date: Thu, 20 Apr 2017 10:10:10 +0000
Subject: [PATCH] [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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300828 91177308-0d34-0410-b5e6-96231b3b80d8
---
 .../AArch64/AsmParser/AArch64AsmParser.cpp    | 35 +++++++------------
 test/MC/AArch64/basic-a64-diagnostics.s       | 14 ++++++++
 2 files changed, 27 insertions(+), 22 deletions(-)

diff --git a/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp b/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp
index cbab68979c5..347cffe72c3 100644
--- a/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp
+++ b/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()));
diff --git a/test/MC/AArch64/basic-a64-diagnostics.s b/test/MC/AArch64/basic-a64-diagnostics.s
index 80e32c48673..ca513327400 100644
--- a/test/MC/AArch64/basic-a64-diagnostics.s
+++ b/test/MC/AArch64/basic-a64-diagnostics.s
@@ -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
@@ -1796,6 +1804,12 @@
 // CHECK-ERROR-NEXT:                    ^
 // CHECK-ERROR-NEXT: error: expected compatible register or floating-point constant
 // 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
-- 
2.50.1