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Diffstat (limited to 'arch/m68k/lib/ashrdi3.c')
-rw-r--r--arch/m68k/lib/ashrdi3.c58
1 files changed, 58 insertions, 0 deletions
diff --git a/arch/m68k/lib/ashrdi3.c b/arch/m68k/lib/ashrdi3.c
new file mode 100644
index 000000000..1d59345f3
--- /dev/null
+++ b/arch/m68k/lib/ashrdi3.c
@@ -0,0 +1,58 @@
+/* ashrdi3.c extracted from gcc-2.7.2/libgcc2.c which is: */
+/* Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
+
+This file is part of GNU CC.
+
+GNU CC 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.
+
+GNU CC 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. */
+
+#define BITS_PER_UNIT 8
+
+typedef int SItype __attribute__ ((mode (SI)));
+typedef unsigned int USItype __attribute__ ((mode (SI)));
+typedef int DItype __attribute__ ((mode (DI)));
+typedef int word_type __attribute__ ((mode (__word__)));
+
+struct DIstruct {SItype high, low;};
+
+typedef union
+{
+ struct DIstruct s;
+ DItype ll;
+} DIunion;
+
+DItype
+__ashrdi3 (DItype u, word_type b)
+{
+ DIunion w;
+ word_type bm;
+ DIunion uu;
+
+ if (b == 0)
+ return u;
+
+ uu.ll = u;
+
+ bm = (sizeof (SItype) * BITS_PER_UNIT) - b;
+ if (bm <= 0)
+ {
+ /* w.s.high = 1..1 or 0..0 */
+ w.s.high = uu.s.high >> (sizeof (SItype) * BITS_PER_UNIT - 1);
+ w.s.low = uu.s.high >> -bm;
+ }
+ else
+ {
+ USItype carries = (USItype)uu.s.high << bm;
+ w.s.high = uu.s.high >> b;
+ w.s.low = ((USItype)uu.s.low >> b) | carries;
+ }
+
+ return w.ll;
+}