Imported gcc-4.4.3

[msp430-gcc.git] / libgcc / config / libbid / bid128_scalb.c

diff --git a/libgcc/config/libbid/bid128_scalb.c b/libgcc/config/libbid/bid128_scalb.c
new file mode 100644 (file)
index 0000000..5897134
--- /dev/null
+++ b/libgcc/config/libbid/bid128_scalb.c
@@ -0,0 +1,96 @@
+/* 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/>.  */
+
+#define BID_128RES
+#include "bid_internal.h"
+
+#define DECIMAL_EXPONENT_BIAS_128 6176
+#define MAX_DECIMAL_EXPONENT_128  12287
+
+
+
+BID128_FUNCTION_ARG128_ARGTYPE2 (bid128_scalb, x, int, n)
+
+     UINT128 CX, CX2, CX8, res;
+     SINT64 exp64;
+     UINT64 sign_x;
+     int exponent_x, rmode;
+
+  // unpack arguments, check for NaN or Infinity
+if (!unpack_BID128_value (&sign_x, &exponent_x, &CX, x)) {
+    // x is Inf. or NaN or 0
+#ifdef SET_STATUS_FLAGS
+if ((x.w[1] & SNAN_MASK64) == SNAN_MASK64)     // y is sNaN
+  __set_status_flags (pfpsf, INVALID_EXCEPTION);
+#endif
+res.w[1] = CX.w[1] & QUIET_MASK64;
+res.w[0] = CX.w[0];
+if (!CX.w[1]) {
+       exp64 = (SINT64) exponent_x + (SINT64) n;
+          if(exp64<0) exp64=0;
+          if(exp64>MAX_DECIMAL_EXPONENT_128) exp64=MAX_DECIMAL_EXPONENT_128;
+       exponent_x = exp64;
+  get_BID128_very_fast (&res, sign_x, exponent_x, CX);
+}
+BID_RETURN (res);
+}
+
+exp64 = (SINT64) exponent_x + (SINT64) n;
+exponent_x = exp64;
+
+if ((UINT32) exponent_x <= MAX_DECIMAL_EXPONENT_128) {
+  get_BID128_very_fast (&res, sign_x, exponent_x, CX);
+  BID_RETURN (res);
+}
+  // check for overflow
+if (exp64 > MAX_DECIMAL_EXPONENT_128) {
+  if (CX.w[1] < 0x314dc6448d93ull) {
+    // try to normalize coefficient
+    do {
+      CX8.w[1] = (CX.w[1] << 3) | (CX.w[0] >> 61);
+      CX8.w[0] = CX.w[0] << 3;
+      CX2.w[1] = (CX.w[1] << 1) | (CX.w[0] >> 63);
+      CX2.w[0] = CX.w[0] << 1;
+      __add_128_128 (CX, CX2, CX8);
+
+      exponent_x--;
+      exp64--;
+    }
+    while (CX.w[1] < 0x314dc6448d93ull
+          && exp64 > MAX_DECIMAL_EXPONENT_128);
+
+  }
+  if (exp64 <= MAX_DECIMAL_EXPONENT_128) {
+    get_BID128_very_fast (&res, sign_x, exponent_x, CX);
+    BID_RETURN (res);
+  } else
+    exponent_x = 0x7fffffff;   // overflow
+}
+  // exponent < 0
+  // the BID pack routine will round the coefficient
+rmode = rnd_mode;
+get_BID128 (&res, sign_x, exponent_x, CX, (unsigned int *) &rmode,
+           pfpsf);
+BID_RETURN (res);
+
+}