[LIBM] Import win-libm from AMD

Source: https://github.com/amd/win-libm
2025-07-30 16:22:26 +00:00 · 2022-06-12 12:02:01 +02:00 · 2022-06-12 12:02:01 +02:00 · 4afb647c78
commit 4afb647c78
parent 081c637c06
82 changed files with 22392 additions and 0 deletions
--- a/sdk/lib/crt/math/libm_sse2/acos.c
+++ b/sdk/lib/crt/math/libm_sse2/acos.c
@ -0,0 +1,145 @@
+
+/*******************************************************************************
+MIT License
+-----------
+
+Copyright (c) 2002-2019 Advanced Micro Devices, Inc.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this Software and associated documentaon 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 "libm.h"
+#include "libm_util.h"
+
+#define USE_VAL_WITH_FLAGS
+#define USE_NAN_WITH_FLAGS
+#define USE_HANDLE_ERROR
+#include "libm_inlines.h"
+#undef USE_NAN_WITH_FLAGS
+#undef USE_VAL_WITH_FLAGS
+#undef USE_HANDLE_ERROR
+
+#include "libm_errno.h"
+
+
+#pragma function(acos)
+
+double FN_PROTOTYPE(acos)(double x)
+{
+  /* Computes arccos(x).
+     The argument is first reduced by noting that arccos(x)
+     is invalid for abs(x) > 1. For denormal and small
+     arguments arccos(x) = pi/2 to machine accuracy.
+     Remaining argument ranges are handled as follows.
+     For abs(x) <= 0.5 use
+     arccos(x) = pi/2 - arcsin(x)
+     = pi/2 - (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:
+     arccos(x) = pi - 2*arcsin(sqrt(1-x)/2)
+     together with the above rational approximation, and
+     reconstruct the terms carefully.
+  */
+
+  /* Some constants and split constants. */
+
+  static const double
+    pi         = 3.1415926535897933e+00, /* 0x400921fb54442d18 */
+    piby2      = 1.5707963267948965580e+00, /* 0x3ff921fb54442d18 */
+    piby2_head = 1.5707963267948965580e+00, /* 0x3ff921fb54442d18 */
+    piby2_tail = 6.12323399573676603587e-17; /* 0x3c91a62633145c07 */
+
+  double u, y, s=0.0, r;
+  int xexp, xnan, transform=0;
+
+  unsigned long ux, aux, xneg;
+  GET_BITS_DP64(x, ux);
+  aux = ux & ~SIGNBIT_DP64;
+  xneg = (ux & SIGNBIT_DP64);
+  xnan = (aux > PINFBITPATT_DP64);
+  xexp = (int)((ux & EXPBITS_DP64) >> EXPSHIFTBITS_DP64) - EXPBIAS_DP64;
+
+  /* Special cases */
+
+  if (xnan)
+    {
+      return _handle_error("acos", OP_ACOS, ux|0x0008000000000000, _DOMAIN,
+                          0, EDOM, x, 0.0, 1);
+    }
+  else if (xexp < -56)
+    { /* y small enough that arccos(x) = pi/2 */
+      return val_with_flags(piby2, AMD_F_INEXACT);
+    }
+  else if (xexp >= 0)
+    { /* abs(x) >= 1.0 */
+      if (x == 1.0)
+        return 0.0;
+      else if (x == -1.0)
+        return val_with_flags(pi, AMD_F_INEXACT);
+      else
+        return _handle_error("acos", OP_ACOS, INDEFBITPATT_DP64, _DOMAIN,
+                            AMD_F_INVALID, EDOM, x, 0.0, 1);
+    }
+
+  if (xneg) y = -x;
+  else y = x;
+
+  transform = (xexp >= -1); /* abs(x) >= 0.5 */
+
+  if (transform)
+    { /* Transform y into the range [0,0.5) */
+      r = 0.5*(1.0 - y);
+      /* VC++ intrinsic call */
+      _mm_store_sd(&s, _mm_sqrt_sd(_mm_setzero_pd(), _mm_load_sd(&r)));
+      y = s;
+    }
+  else
+    r = y*y;
+
+  /* Use a rational approximation for [0.0, 0.5] */
+
+  u = r*(0.227485835556935010735943483075 +
+         (-0.445017216867635649900123110649 +
+          (0.275558175256937652532686256258 +
+           (-0.0549989809235685841612020091328 +
+            (0.00109242697235074662306043804220 +
+             0.0000482901920344786991880522822991*r)*r)*r)*r)*r)/
+    (1.36491501334161032038194214209 +
+     (-3.28431505720958658909889444194 +
+      (2.76568859157270989520376345954 +
+       (-0.943639137032492685763471240072 +
+	0.105869422087204370341222318533*r)*r)*r)*r);
+
+  if (transform)
+    { /* Reconstruct acos carefully in transformed region */
+      if (xneg) return pi - 2.0*(s+(y*u - piby2_tail));
+      else
+	{
+	  double c, s1;
+	  unsigned long us;
+	  GET_BITS_DP64(s, us);
+	  PUT_BITS_DP64(0xffffffff00000000 & us, s1);
+	  c = (r-s1*s1)/(s+s1);
+          return 2.0*s1 + (2.0*c+2.0*y*u);
+	}
+    }
+  else
+    return piby2_head - (x - (piby2_tail - x*u));
+}