summaryrefslogtreecommitdiff
path: root/sysdeps/powerpc/q_lltoq.c
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/powerpc/q_lltoq.c')
-rw-r--r--sysdeps/powerpc/q_lltoq.c52
1 files changed, 52 insertions, 0 deletions
diff --git a/sysdeps/powerpc/q_lltoq.c b/sysdeps/powerpc/q_lltoq.c
new file mode 100644
index 0000000000..6222eff9fc
--- /dev/null
+++ b/sysdeps/powerpc/q_lltoq.c
@@ -0,0 +1,52 @@
+/* 64-bit fixed point signed integer to 128-bit floating point.
+ Copyright (C) 1997 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If not,
+ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include <quad_float.h>
+
+/* long double _q_ulltoq(long long a);
+ Convert 'a' to long double.
+ */
+
+void
+__q_lltoq(unsigned int result[4], long long a)
+{
+ unsigned rx;
+ int cs, css;
+
+ /* Calculate absolute value of 'a'. */
+ unsigned long long ua = (a ^ a >> 63) - (a >> 63);
+
+ /* Normalize. */
+ cs = cntlzd(a);
+ ua <<= cs+1;
+
+ /* Calculate the exponent, in 4 easy instructions. */
+ css = 63-cs;
+ rx = 16383+css << 16 & ~css;
+
+ /* Copy the sign bit from 'a'. */
+ asm ("rlwimi %0,%1,0,0,0": "=r"(rx) : "r"(a >> 32), "0"(rx));
+
+ /* Put it all together. */
+ result[3] = 0;
+ asm ("rlwimi %0,%1,16,16,31": "=r"(result[0]) : "r"(ua >> 32), "0"(rx));
+ ua <<= 16;
+ result[2] = ua;
+ result[1] = ua >> 32;
+}