[Libclc-dev] [PATCH 5/9] Implement asinpi builtin
Tom Stellard
thomas.stellard at amd.com
Thu Mar 12 13:11:42 PDT 2015
This implementation was ported from the AMD builtin library
and has been tested with piglit, OpenCV, and the ocl conformance tests.
---
generic/include/clc/clc.h | 1 +
generic/include/clc/math/asinpi.h | 24 +++++
generic/include/clc/math/asinpi.inc | 23 +++++
generic/lib/SOURCES | 1 +
generic/lib/math/asinpi.cl | 170 ++++++++++++++++++++++++++++++++++++
5 files changed, 219 insertions(+)
create mode 100644 generic/include/clc/math/asinpi.h
create mode 100644 generic/include/clc/math/asinpi.inc
create mode 100644 generic/lib/math/asinpi.cl
diff --git a/generic/include/clc/clc.h b/generic/include/clc/clc.h
index 44abf12..eb870bd 100644
--- a/generic/include/clc/clc.h
+++ b/generic/include/clc/clc.h
@@ -37,6 +37,7 @@
#include <clc/math/acospi.h>
#include <clc/math/asin.h>
#include <clc/math/asinh.h>
+#include <clc/math/asinpi.h>
#include <clc/math/atan.h>
#include <clc/math/atan2.h>
#include <clc/math/copysign.h>
diff --git a/generic/include/clc/math/asinpi.h b/generic/include/clc/math/asinpi.h
new file mode 100644
index 0000000..781f850
--- /dev/null
+++ b/generic/include/clc/math/asinpi.h
@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2014, 2015 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#define __CLC_BODY <clc/math/asinpi.inc>
+#include <clc/math/gentype.inc>
diff --git a/generic/include/clc/math/asinpi.inc b/generic/include/clc/math/asinpi.inc
new file mode 100644
index 0000000..0b088f0
--- /dev/null
+++ b/generic/include/clc/math/asinpi.inc
@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2014, 2015 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+_CLC_OVERLOAD _CLC_DECL __CLC_GENTYPE asinpi(__CLC_GENTYPE x);
diff --git a/generic/lib/SOURCES b/generic/lib/SOURCES
index 48f459b..e6bc95b 100644
--- a/generic/lib/SOURCES
+++ b/generic/lib/SOURCES
@@ -66,6 +66,7 @@ math/acosh.cl
math/acospi.cl
math/asin.cl
math/asinh.cl
+math/asinpi.cl
math/atan.cl
math/atan2.cl
math/copysign.cl
diff --git a/generic/lib/math/asinpi.cl b/generic/lib/math/asinpi.cl
new file mode 100644
index 0000000..511d74e
--- /dev/null
+++ b/generic/lib/math/asinpi.cl
@@ -0,0 +1,170 @@
+/*
+ * Copyright (c) 2014,2015 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <clc/clc.h>
+
+#include "math.h"
+#include "../clcmacro.h"
+
+_CLC_OVERLOAD _CLC_DEF float asinpi(float x) {
+ // Computes arcsin(x).
+ // The argument is first reduced by noting that arcsin(x)
+ // is invalid for abs(x) > 1 and arcsin(-x) = -arcsin(x).
+ // For denormal and small arguments arcsin(x) = x to machine
+ // accuracy. Remaining argument ranges are handled as follows.
+ // For abs(x) <= 0.5 use
+ // arcsin(x) = x + x^3*R(x^2)
+ // where R(x^2) is a rational minimax approximation to
+ // (arcsin(x) - x)/x^3.
+ // For abs(x) > 0.5 exploit the identity:
+ // arcsin(x) = pi/2 - 2*arcsin(sqrt(1-x)/2)
+ // together with the above rational approximation, and
+ // reconstruct the terms carefully.
+
+
+ const float pi = 3.1415926535897933e+00f;
+ const float piby2_tail = 7.5497894159e-08F; /* 0x33a22168 */
+ const float hpiby2_head = 7.8539812565e-01F; /* 0x3f490fda */
+
+ uint ux = as_uint(x);
+ uint aux = ux & EXSIGNBIT_SP32;
+ uint xs = ux ^ aux;
+ float shalf = as_float(xs | as_uint(0.5f));
+
+ int xexp = (int)(aux >> EXPSHIFTBITS_SP32) - EXPBIAS_SP32;
+
+ float y = as_float(aux);
+
+ // abs(x) >= 0.5
+ int transform = xexp >= -1;
+
+ float y2 = y * y;
+ float rt = 0.5f * (1.0f - y);
+ float r = transform ? rt : y2;
+
+ // Use a rational approximation for [0.0, 0.5]
+ float a = mad(r,
+ mad(r,
+ mad(r, -0.00396137437848476485201154797087F, -0.0133819288943925804214011424456F),
+ -0.0565298683201845211985026327361F),
+ 0.184161606965100694821398249421F);
+ float b = mad(r, -0.836411276854206731913362287293F, 1.10496961524520294485512696706F);
+ float u = r * MATH_DIVIDE(a, b);
+
+ float s = MATH_SQRT(r);
+ float s1 = as_float(as_uint(s) & 0xffff0000);
+ float c = MATH_DIVIDE(mad(-s1, s1, r), s + s1);
+ float p = mad(2.0f*s, u, -mad(c, -2.0f, piby2_tail));
+ float q = mad(s1, -2.0f, hpiby2_head);
+ float vt = hpiby2_head - (p - q);
+ float v = mad(y, u, y);
+ v = transform ? vt : v;
+ v = MATH_DIVIDE(v, pi);
+ float xbypi = MATH_DIVIDE(x, pi);
+
+ float ret = as_float(xs | as_uint(v));
+ ret = aux > 0x3f800000U ? as_float(QNANBITPATT_SP32) : ret;
+ ret = aux == 0x3f800000U ? shalf : ret;
+ ret = xexp < -14 ? xbypi : ret;
+
+ return ret;
+}
+
+_CLC_UNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, float, asinpi, float)
+
+#ifdef cl_khr_fp64
+#pragma OPENCL EXTENSION cl_khr_fp64 : enable
+
+_CLC_OVERLOAD _CLC_DEF double asinpi(double x) {
+ // Computes arcsin(x).
+ // The argument is first reduced by noting that arcsin(x)
+ // is invalid for abs(x) > 1 and arcsin(-x) = -arcsin(x).
+ // For denormal and small arguments arcsin(x) = x to machine
+ // accuracy. Remaining argument ranges are handled as follows.
+ // For abs(x) <= 0.5 use
+ // arcsin(x) = x + x^3*R(x^2)
+ // where R(x^2) is a rational minimax approximation to
+ // (arcsin(x) - x)/x^3.
+ // For abs(x) > 0.5 exploit the identity:
+ // arcsin(x) = pi/2 - 2*arcsin(sqrt(1-x)/2)
+ // together with the above rational approximation, and
+ // reconstruct the terms carefully.
+
+ const double pi = 0x1.921fb54442d18p+1;
+ const double piby2_tail = 6.1232339957367660e-17; /* 0x3c91a62633145c07 */
+ const double hpiby2_head = 7.8539816339744831e-01; /* 0x3fe921fb54442d18 */
+
+ double y = fabs(x);
+ int xneg = as_int2(x).hi < 0;
+ int xexp = (as_int2(y).hi >> 20) - EXPBIAS_DP64;
+
+ // abs(x) >= 0.5
+ int transform = xexp >= -1;
+
+ double rt = 0.5 * (1.0 - y);
+ double y2 = y * y;
+ double r = transform ? rt : y2;
+
+ // Use a rational approximation for [0.0, 0.5]
+ double un = fma(r,
+ fma(r,
+ fma(r,
+ fma(r,
+ fma(r, 0.0000482901920344786991880522822991,
+ 0.00109242697235074662306043804220),
+ -0.0549989809235685841612020091328),
+ 0.275558175256937652532686256258),
+ -0.445017216867635649900123110649),
+ 0.227485835556935010735943483075);
+
+ double ud = fma(r,
+ fma(r,
+ fma(r,
+ fma(r, 0.105869422087204370341222318533,
+ -0.943639137032492685763471240072),
+ 2.76568859157270989520376345954),
+ -3.28431505720958658909889444194),
+ 1.36491501334161032038194214209);
+
+ double u = r * MATH_DIVIDE(un, ud);
+
+
+ // Reconstruct asin carefully in transformed region
+ double s = sqrt(r);
+ double sh = as_double(as_ulong(s) & 0xffffffff00000000UL);
+ double c = MATH_DIVIDE(fma(-sh, sh, r), s + sh);
+ double p = fma(2.0*s, u, -fma(-2.0, c, piby2_tail));
+ double q = fma(-2.0, sh, hpiby2_head);
+ double vt = hpiby2_head - (p - q);
+ double v = fma(y, u, y);
+ v = transform ? vt : v;
+
+ v = xexp < -28 ? y : v;
+ v = MATH_DIVIDE(v, pi);
+ v = xexp >= 0 ? as_double(QNANBITPATT_DP64) : v;
+ v = y == 1.0 ? 0.5 : v;
+ return xneg ? -v : v;
+}
+
+_CLC_UNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, double, asinpi, double)
+
+#endif
--
2.0.4
More information about the Libclc-dev
mailing list