aboutsummaryrefslogtreecommitdiff
path: root/arch/m68k/lib/ashrdi3.c
diff options
context:
space:
mode:
authorTom Rini <trini@konsulko.com>2023-03-27 15:19:57 -0400
committerTom Rini <trini@konsulko.com>2023-03-27 15:19:57 -0400
commit605bc145f91d2a28ba2e517cae4e53e255e34b6f (patch)
treea8df36d6569d441bc013399ff7dafff07cd36657 /arch/m68k/lib/ashrdi3.c
parentfde439219ff53a46bdd5dff69e049ccd4be57310 (diff)
parent41a88ad529b3943b1e465846eb24fe2c29203e35 (diff)
Merge branch 'master' into next
Diffstat (limited to 'arch/m68k/lib/ashrdi3.c')
-rw-r--r--arch/m68k/lib/ashrdi3.c48
1 files changed, 48 insertions, 0 deletions
diff --git a/arch/m68k/lib/ashrdi3.c b/arch/m68k/lib/ashrdi3.c
new file mode 100644
index 0000000000..e144378b7f
--- /dev/null
+++ b/arch/m68k/lib/ashrdi3.c
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * ashrdi3.c extracted from gcc-2.7.2/libgcc2.c which is:
+ * Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
+ */
+
+#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;
+} di_union;
+
+DItype __ashrdi3(DItype u, word_type b)
+{
+ di_union w;
+ word_type bm;
+ di_union 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;
+}
+