diff options
Diffstat (limited to 'Source/Core/Common/Src/MathUtil.cpp')
| -rw-r--r-- | Source/Core/Common/Src/MathUtil.cpp | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/Source/Core/Common/Src/MathUtil.cpp b/Source/Core/Common/Src/MathUtil.cpp index e2dbaa0640..88e929ec41 100644 --- a/Source/Core/Common/Src/MathUtil.cpp +++ b/Source/Core/Common/Src/MathUtil.cpp @@ -22,9 +22,64 @@ #include <cmath> +namespace { + static u32 saved_sse_state = _mm_getcsr(); static const u32 default_sse_state = _mm_getcsr(); +} + +namespace MathUtil +{ + +int ClassifyFP(double dvalue) +{ + // TODO: Optimize the below to be as fast as possible. + IntDouble value; + value.d = dvalue; + // 5 bits (C, <, >, =, ?) + // easy cases first + if (value.i == 0) { + // positive zero + return 0x2; + } else if (value.i == 0x8000000000000000ULL) { + // negative zero + return 0x12; + } else if (value.i == 0x7FF0000000000000ULL) { + // positive inf + return 0x5; + } else if (value.i == 0xFFF0000000000000ULL) { + // negative inf + return 0x9; + } else { + // OK let's dissect this thing. + int sign = value.i >> 63; + int exp = (int)((value.i >> 52) & 0x7FF); + if (exp >= 1 && exp <= 2046) { + // Nice normalized number. + if (sign) { + return 0x8; // negative + } else { + return 0x4; // positive + } + } + u64 mantissa = value.i & 0x000FFFFFFFFFFFFFULL; + if (exp == 0 && mantissa) { + // Denormalized number. + if (sign) { + return 0x18; + } else { + return 0x14; + } + } else if (exp == 0x7FF && mantissa /* && mantissa_top*/) { + return 0x11; // Quiet NAN + } + } + + return 0x4; +} + +} // namespace void LoadDefaultSSEState() { @@ -145,3 +200,4 @@ void Matrix44::Multiply(const Matrix44 &a, const Matrix44 &b, Matrix44 &result) { MatrixMul(4, a.data, b.data, result.data); } + |