[llvm-commits] [llvm] r141816 - in /llvm/trunk: lib/Support/APFloat.cpp unittests/ADT/APFloatTest.cpp

[Francois Pichet]

On Wed, Oct 12, 2011 at 5:51 PM, Eli Friedman <eli.friedman at gmail.com> wrote:
> Author: efriedma
> Date: Wed Oct 12 16:51:36 2011
> New Revision: 141816
>
> URL: http://llvm.org/viewvc/llvm-project?rev=141816&view=rev
> Log:
> Fix APFloat::getLargest so that it actually returns the correct value.  Found by accident while reviewing a patch to nearby code.
>
>
> Modified:
>    llvm/trunk/lib/Support/APFloat.cpp
>    llvm/trunk/unittests/ADT/APFloatTest.cpp
>
> Modified: llvm/trunk/lib/Support/APFloat.cpp
> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/APFloat.cpp?rev=141816&r1=141815&r2=141816&view=diff
> ==============================================================================
> --- llvm/trunk/lib/Support/APFloat.cpp (original)
> +++ llvm/trunk/lib/Support/APFloat.cpp Wed Oct 12 16:51:36 2011
> @@ -3243,8 +3243,9 @@
>     significand[i] = ~((integerPart) 0);
>
>   // ...and then clear the top bits for internal consistency.
> -  significand[N-1] &=
> -    (((integerPart) 1) << ((Sem.precision % integerPartWidth) - 1)) - 1;
> +  if (Sem.precision % integerPartWidth != 0)
> +    significand[N-1] &=
> +      (((integerPart) 1) << (Sem.precision % integerPartWidth)) - 1;
>
>   return Val;
>  }
>
> Modified: llvm/trunk/unittests/ADT/APFloatTest.cpp
> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/unittests/ADT/APFloatTest.cpp?rev=141816&r1=141815&r2=141816&view=diff
> ==============================================================================
> --- llvm/trunk/unittests/ADT/APFloatTest.cpp (original)
> +++ llvm/trunk/unittests/ADT/APFloatTest.cpp Wed Oct 12 16:51:36 2011
> @@ -648,4 +648,9 @@
>   EXPECT_FALSE(APFloat(1.40129846e-45f).getExactInverse(0));
>  }
>
> +TEST(APFloatTest, getLargest) {
> +  EXPECT_EQ(3.40282347e+38f, APFloat::getLargest(APFloat::IEEEsingle).convertToFloat());
> +  EXPECT_EQ(1.7976931348623157e+308, APFloat::getLargest(APFloat::IEEEdouble).convertToDouble());
> +}

On MSVC:

1>ADT\APFloatTest.cpp(652): error C2177: constant too big
1>ADT\APFloatTest.cpp(652): error C2177: constant too big