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test: remove dead code in an old test.

legacy
Sam Hocevar sam 11 years ago
parent
commit
410513f8ac
1 changed files with 11 additions and 103 deletions
  1. +11
    -103
      test/math/poly.cpp

+ 11
- 103
test/math/poly.cpp View File

@@ -19,120 +19,28 @@
using namespace lol;
using namespace std;

float adjustf(float f, int i) __attribute__((noinline));
float adjustf(float f, int i)
mat4 multiply_copy(mat4 m1, mat4 m2, mat4 m3)
{
union { float f; uint32_t x; } u = { f };
u.x += i;
return u.f;
return m1 * m2 * m3;
}

double adjust(double f, int i) __attribute__((noinline));
double adjust(double f, int i)
mat4 multiply_ref(mat4 const &m1, mat4 const &m2, mat4 const &m3)
{
union { double f; uint64_t x; } u = { f };
u.x += i;
return u.f;
}

static void inspect(float f)
{
union { float f; uint32_t x; } u = { f };
printf("%08x %14.12g -- ", u.x, u.f);
int i = (u.x & 0x7fffffu) | 0x800000u;
int j = 23 - ((u.x >> 23) & 0xff) + ((1 << 7) - 1);
if (u.f <= 0)
i = -i;
printf("%i / 2^%i = %14.12g\n", i, j, (float)i / (1LLu << j));
}

//#define float double
#if 1
static float const a0 = 1.0;
static float const a1 = -0.1666666666663036;
static float const a2 = 0.008333333325075758;
static float const a3 = -0.0001984126372689299;
static float const a4 = 2.755533925906394e-06;
static float const a5 = -2.476042626296988e-08;
static float const a6 = 0.0;
#elif 0
static float const a0 = adjust(0.9999999999999376, 0);
static float const a1 = adjust(-0.1666666666643236, 0);
static float const a2 = adjust(0.008333333318766562, 0);
static float const a3 = adjust(-0.0001984126641174625, 0);
static float const a4 = adjust(2.755693193297308e-006, 0);
static float const a5 = adjust(-2.502951900290311e-008, 0);
static float const a6 = adjust(1.540117123154927e-010, 0);
#elif 0
static float const a0 = adjust(1.0, 0);
static float const a1 = adjust(-0.1666666666372165, 0);
static float const a2 = adjust(0.008333332748323419, 0);
static float const a3 = adjust(-0.0001984108245332497, 0);
static float const a4 = adjust(2.753619853326498e-06, 0);
static float const a5 = adjust(-2.407483949485896e-08, 0);
static float const a6 = 0.0;
#else
static float const a0 = adjust(0.9999999946887117, 0);
static float const a1 = adjust(-0.1666665668590824, 0);
static float const a2 = adjust(0.008333025160523476, 0);
static float const a3 = adjust(-0.0001980741944205014, 0);
static float const a4 = adjust(2.60190356966559e-06, 0); // -900 in floats
static float const a5 = 0.0;
static float const a6 = 0.0;
#endif

static float floatsin(float f)
{
return lol_sin(f);
//static float const k = (float)real::R_2_PI();

//f *= k;
float f2 = f * f;
float f4 = f2 * f2;
return f * (a0 + f4 * (a2 + f4 * (a4 + f4 * a6)) + f2 * (a1 + f4 * (a3 + f4 * a5)));
//return f * (a0 + f2 * (a1 + f2 * (a2 + f2 * (a3 + f2 * (a4 + f2 * (a5 + f2 * a6))))));
//return f * (a0 + a1 * f2 + a2 * f2 * f2 + a3 * f2 * f2 * f2 + a4 * f2 * f2 * f2 * f2 + a5 * f2 * f2 * f2 * f2 * f2 + a6 * f2 * f2 * f2 * f2 * f2 * f2);
#undef float
return m1 * m2 * m3;
}

int main(int argc, char **argv)
{
UNUSED(argc, argv);

typedef union { float f; uint32_t x; } flint;

int error[5] = { 0 };

inspect(a0);
inspect(a1);
inspect(a2);
inspect(a3);
inspect(a4);
inspect(a5);

for (flint u = { (float)real::R_PI_2() }; u.f > 1e-30; u.x -= 1)
{
union { float f; uint32_t x; } s1 = { sinf(adjustf(u.f, 0)) };
union { float f; uint32_t x; } s2 = { floatsin(adjustf(u.f, 0)) };
int e = lol::abs((int)(s1.x - s2.x));
switch (e)
{
case 3:
case 2:
case 1:
if (lol::abs((double)s1.f - (double)s2.f) > 1e-10 * lol::abs(s1.f))
printf("%15.13g %08x: %15.13g %15.13g %08x %08x\n", u.f, u.x, s1.f, s2.f, s1.x, s2.x);
case 0:
error[e]++;
break;
default:
error[4]++;
break;
}
}
mat4 a = mat4::rotate(0.1f, vec3(1.f, 1.f, 0.f));
mat4 b = mat4::rotate(0.1f, vec3(0.f, 0.f, 1.f));
mat4 m = mat4(1.f);

printf("exact: %i off by 1: %i by 2: %i by 3: %i error: %i\n",
error[0], error[1], error[2], error[3], error[4]);
for (int i = 0; i < 40000000; ++i)
//m = multiply_copy(a, m, b);
m = multiply_ref(a, m, b);
m.printf();

return EXIT_SUCCESS;
}


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