| /*------------------------------------------------------------------------- |
| * drawElements Base Portability Library |
| * ------------------------------------- |
| * |
| * Copyright 2015 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| *//*! |
| * \file |
| * \brief Testing of deMath functions. |
| *//*--------------------------------------------------------------------*/ |
| |
| #include "deMath.h" |
| #include "deRandom.h" |
| |
| DE_BEGIN_EXTERN_C |
| |
| static deBool conversionToFloatLosesPrecision (deInt32 x) |
| { |
| if (x == -0x7FFFFFFF - 1) |
| return DE_FALSE; |
| else if (x < 0) |
| return conversionToFloatLosesPrecision(-x); |
| else if (x == 0) |
| return DE_FALSE; |
| else if (((deUint32)x & 0x1) == 0) |
| return conversionToFloatLosesPrecision(x >> 1); /* remove trailing zeros */ |
| else |
| return x > ((1 << 24) - 1); /* remaining part does not fit in the mantissa? */ |
| } |
| |
| static void testSingleInt32ToFloat (deInt32 x) |
| { |
| /* roundTowardsToNegInf(x) <= round(x) <= roundTowardsPosInf(x). */ |
| /* \note: Need to use inequalities since round(x) returns arbitrary precision floats. */ |
| DE_TEST_ASSERT(deInt32ToFloatRoundToNegInf(x) <= deInt32ToFloat(x)); |
| DE_TEST_ASSERT(deInt32ToFloat(x) <= deInt32ToFloatRoundToPosInf(x)); |
| |
| /* if precision is lost, floor(x) < ceil(x). Else floor(x) == ceil(x) */ |
| if (conversionToFloatLosesPrecision(x)) |
| DE_TEST_ASSERT(deInt32ToFloatRoundToNegInf(x) < deInt32ToFloatRoundToPosInf(x)); |
| else |
| DE_TEST_ASSERT(deInt32ToFloatRoundToNegInf(x) == deInt32ToFloatRoundToPosInf(x)); |
| |
| /* max one ulp from each other */ |
| if (deInt32ToFloatRoundToNegInf(x) < deInt32ToFloatRoundToPosInf(x)) |
| { |
| union |
| { |
| float f; |
| deInt32 u; |
| } v0, v1; |
| |
| v0.f = deInt32ToFloatRoundToNegInf(x); |
| v1.f = deInt32ToFloatRoundToPosInf(x); |
| |
| DE_TEST_ASSERT(v0.u + 1 == v1.u || v0.u == v1.u + 1); |
| } |
| } |
| |
| static void testInt32ToFloat (void) |
| { |
| const int numIterations = 2500000; |
| |
| int sign; |
| int numBits; |
| int delta; |
| int ndx; |
| deRandom rnd; |
| |
| deRandom_init(&rnd, 0xdeadbeefu-1); |
| |
| for (sign = -1; sign < 1; ++sign) |
| for (numBits = 0; numBits < 32; ++numBits) |
| for (delta = -2; delta < 3; ++delta) |
| { |
| const deInt64 x = (deInt64)(sign == -1 ? (-1) : (+1)) * (1LL << (deInt64)numBits) + (deInt64)delta; |
| |
| /* would overflow */ |
| if (x > 0x7FFFFFFF || x < -0x7FFFFFFF - 1) |
| continue; |
| |
| testSingleInt32ToFloat((deInt32)x); |
| } |
| |
| for (ndx = 0; ndx < numIterations; ++ndx) |
| testSingleInt32ToFloat((deInt32)deRandom_getUint32(&rnd)); |
| } |
| |
| void deMath_selfTest (void) |
| { |
| /* Test Int32ToFloat*(). */ |
| testInt32ToFloat(); |
| } |
| |
| DE_END_EXTERN_C |