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-rw-r--r--gcc-4.4.3/libgcc/config/libbid/bid64_scalb.c105
1 files changed, 105 insertions, 0 deletions
diff --git a/gcc-4.4.3/libgcc/config/libbid/bid64_scalb.c b/gcc-4.4.3/libgcc/config/libbid/bid64_scalb.c
new file mode 100644
index 000000000..a565d6598
--- /dev/null
+++ b/gcc-4.4.3/libgcc/config/libbid/bid64_scalb.c
@@ -0,0 +1,105 @@
+/* Copyright (C) 2007, 2009 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 3, or (at your option) any later
+version.
+
+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.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+<http://www.gnu.org/licenses/>. */
+
+#include "bid_internal.h"
+
+#define MAX_FORMAT_DIGITS 16
+#define DECIMAL_EXPONENT_BIAS 398
+#define MAX_DECIMAL_EXPONENT 767
+
+#if DECIMAL_CALL_BY_REFERENCE
+
+void
+bid64_scalb (UINT64 * pres, UINT64 * px,
+ int *pn _RND_MODE_PARAM _EXC_FLAGS_PARAM _EXC_MASKS_PARAM
+ _EXC_INFO_PARAM) {
+ UINT64 x;
+ int n;
+#else
+
+UINT64
+bid64_scalb (UINT64 x,
+ int n _RND_MODE_PARAM _EXC_FLAGS_PARAM _EXC_MASKS_PARAM
+ _EXC_INFO_PARAM) {
+#endif
+ UINT64 sign_x, coefficient_x, res;
+ SINT64 exp64;
+ int exponent_x, rmode;
+
+#if DECIMAL_CALL_BY_REFERENCE
+#if !DECIMAL_GLOBAL_ROUNDING
+ _IDEC_round rnd_mode = *prnd_mode;
+#endif
+ x = *px;
+ n = *pn;
+#endif
+
+ // unpack arguments, check for NaN or Infinity
+ if (!unpack_BID64 (&sign_x, &exponent_x, &coefficient_x, x)) {
+ // x is Inf. or NaN or 0
+#ifdef SET_STATUS_FLAGS
+ if ((x & SNAN_MASK64) == SNAN_MASK64) // y is sNaN
+ __set_status_flags (pfpsf, INVALID_EXCEPTION);
+#endif
+ if (coefficient_x)
+ res = coefficient_x & QUIET_MASK64;
+ else {
+ exp64 = (SINT64) exponent_x + (SINT64) n;
+ if(exp64<0) exp64=0;
+ if(exp64>MAX_DECIMAL_EXPONENT) exp64=MAX_DECIMAL_EXPONENT;
+ exponent_x = exp64;
+ res = very_fast_get_BID64 (sign_x, exponent_x, coefficient_x); // 0
+ }
+ BID_RETURN (res);
+ }
+
+ exp64 = (SINT64) exponent_x + (SINT64) n;
+ exponent_x = exp64;
+
+ if ((UINT32) exponent_x <= MAX_DECIMAL_EXPONENT) {
+ res = very_fast_get_BID64 (sign_x, exponent_x, coefficient_x);
+ BID_RETURN (res);
+ }
+ // check for overflow
+ if (exp64 > MAX_DECIMAL_EXPONENT) {
+ // try to normalize coefficient
+ while ((coefficient_x < 1000000000000000ull)
+ && (exp64 > MAX_DECIMAL_EXPONENT)) {
+ // coefficient_x < 10^15, scale by 10
+ coefficient_x = (coefficient_x << 1) + (coefficient_x << 3);
+ exponent_x--;
+ exp64--;
+ }
+ if (exp64 <= MAX_DECIMAL_EXPONENT) {
+ res = very_fast_get_BID64 (sign_x, exponent_x, coefficient_x);
+ BID_RETURN (res);
+ } else
+ exponent_x = 0x7fffffff; // overflow
+ }
+ // exponent < 0
+ // the BID pack routine will round the coefficient
+ rmode = rnd_mode;
+ res = get_BID64 (sign_x, exponent_x, coefficient_x, rmode, pfpsf);
+ BID_RETURN (res);
+
+}