1 files changed, 100 insertions, 0 deletions
diff --git a/libgcc/config/libbid/bid64_logb.c b/libgcc/config/libbid/bid64_logb.c
new file mode 100644
index 00000000000..04c8e0fff1d
--- /dev/null
+++ b/libgcc/config/libbid/bid64_logb.c
@@ -0,0 +1,100 @@
+/* Copyright (C) 2007  Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 2, or (at your option) any later
+version.
+
+In addition to the permissions in the GNU General Public License, the
+Free Software Foundation gives you unlimited permission to link the
+compiled version of this file into combinations with other programs,
+and to distribute those combinations without any restriction coming
+from the use of this file.  (The General Public License restrictions
+do apply in other respects; for example, they cover modification of
+the file, and distribution when not linked into a combine
+executable.)
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING.  If not, write to the Free
+Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301, USA.  */
+
+#include "bid_internal.h"
+
+#define MAX_FORMAT_DIGITS     16
+#define DECIMAL_EXPONENT_BIAS 398
+
+#if DECIMAL_CALL_BY_REFERENCE
+
+void
+__bid64_logb (UINT64 * pres,
+	    UINT64 *
+	    px _RND_MODE_PARAM _EXC_FLAGS_PARAM _EXC_MASKS_PARAM
+	    _EXC_INFO_PARAM) {
+  UINT64 x;
+#else
+
+UINT64
+__bid64_logb (UINT64 x _RND_MODE_PARAM _EXC_FLAGS_PARAM
+	    _EXC_MASKS_PARAM _EXC_INFO_PARAM) {
+#endif
+  UINT64 sign_x, coefficient_x, res;
+  UINT64 logb_coeff, logb_sign;
+  SINT32 sign_e;
+  int exponent_x;
+
+#if DECIMAL_CALL_BY_REFERENCE
+#if !DECIMAL_GLOBAL_ROUNDING
+  _IDEC_round rnd_mode = *prnd_mode;
+#endif
+  x = *px;
+#endif
+
+  // unpack arguments, check for NaN or Infinity
+  if (!unpack_BID64 (&sign_x, &exponent_x, &coefficient_x, x)) {
+    // x is Inf. or NaN
+
+    // test if x is NaN
+    if ((x & 0x7c00000000000000ull) == 0x7c00000000000000ull) {
+      res = x;
+      BID_RETURN (res);
+    }
+    // x is Infinity?
+    if ((x & 0x7800000000000000ull) == 0x7800000000000000ull) {
+      res = 0x7800000000000000ull;
+      BID_RETURN (res);
+    }
+    // x is 0
+    {
+#ifdef SET_STATUS_FLAGS
+      __set_status_flags (pfpsf, ZERO_DIVIDE_EXCEPTION);
+#endif
+      res = 0xf800000000000000ull;
+      BID_RETURN (res);
+    }
+  }
+
+  exponent_x =
+    exponent_x - DECIMAL_EXPONENT_BIAS + MAX_FORMAT_DIGITS - 1;
+
+  // extract sign and absolute value from exponent_x
+  sign_e = ((SINT32) exponent_x) >> 31;
+  exponent_x = (exponent_x + sign_e) ^ sign_e;
+
+  logb_coeff = exponent_x;
+  logb_sign = sign_e & 1;
+  logb_sign <<= 63;
+
+  res =
+    very_fast_get_BID64_small_mantissa (logb_sign,
+					DECIMAL_EXPONENT_BIAS,
+					logb_coeff);
+  BID_RETURN (res);
+}