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authorJerry Jelinek <jerry.jelinek@joyent.com>2020-07-09 11:42:13 +0000
committerJerry Jelinek <jerry.jelinek@joyent.com>2020-07-09 11:42:13 +0000
commit466fd238ca24f5d17cd0b74a70dfc36ab67a624b (patch)
tree6fadeb6f60d7720619c51da693dc4d571e0df7e3 /usr/src/common/util/multi3.c
parentb97f5b09ef2e4af27e3cc4addd8abe5fc7c4d817 (diff)
parent4a663bac9c5f9f82a5f633bc9639bbee3c2317ff (diff)
downloadillumos-joyent-466fd238ca24f5d17cd0b74a70dfc36ab67a624b.tar.gz
[illumos-gate merge]
commit 4a663bac9c5f9f82a5f633bc9639bbee3c2317ff 12904 Update nvme health logpage and temp thresholds commit 480497bc2ff96b447dc09403a6c187a1593ac1ec 12934 sockfs rights test should close unneeded descriptors commit fdb2a7e9480266dfaa0b5aaa0e1237456552f332 12881 sparcv9: add __multi3 commit 7fc77f3f3f63424c569601711f173702dbfd5c45 12927 loader: move zfs_boot_args to bootargs.h commit 1c0fc4547783fdfd7365d5d483e2750915523d44 6089 The comment for svc_callout_find() should be improved commit 66373fa702508a0a41753138f0b10f985c7e058d 12902 epoll should nominally support EPOLLEXCLUSIVE commit 33f84ecfada5880d94e9bfc5af7954d41e5664d5 12924 blkdev needs to be better at handling attach failures
Diffstat (limited to 'usr/src/common/util/multi3.c')
-rw-r--r--usr/src/common/util/multi3.c63
1 files changed, 63 insertions, 0 deletions
diff --git a/usr/src/common/util/multi3.c b/usr/src/common/util/multi3.c
new file mode 100644
index 0000000000..b098eb37ac
--- /dev/null
+++ b/usr/src/common/util/multi3.c
@@ -0,0 +1,63 @@
+/*
+ * Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+ * See https://llvm.org/LICENSE.txt for license information.
+ * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+ */
+
+#include <sys/byteorder.h>
+
+#define CHAR_BIT 8
+
+typedef int di_int __attribute__((mode(DI)));
+typedef unsigned int du_int __attribute__((mode(DI)));
+typedef int ti_int __attribute__((mode(TI)));
+
+typedef union {
+ ti_int all;
+ struct {
+#if _LITTLE_ENDIAN
+ du_int low;
+ di_int high;
+#else
+ di_int high;
+ du_int low;
+#endif /* _LITTLE_ENDIAN */
+ } s;
+} twords;
+
+/* Returns: a * b */
+static
+ti_int
+__mulddi3(du_int a, du_int b)
+{
+ twords r;
+ const int bits_in_dword_2 = (int)(sizeof (di_int) * CHAR_BIT) / 2;
+ const du_int lower_mask = (du_int)~0 >> bits_in_dword_2;
+ r.s.low = (a & lower_mask) * (b & lower_mask);
+ du_int t = r.s.low >> bits_in_dword_2;
+ r.s.low &= lower_mask;
+ t += (a >> bits_in_dword_2) * (b & lower_mask);
+ r.s.low += (t & lower_mask) << bits_in_dword_2;
+ r.s.high = t >> bits_in_dword_2;
+ t = r.s.low >> bits_in_dword_2;
+ r.s.low &= lower_mask;
+ t += (b >> bits_in_dword_2) * (a & lower_mask);
+ r.s.low += (t & lower_mask) << bits_in_dword_2;
+ r.s.high += t >> bits_in_dword_2;
+ r.s.high += (a >> bits_in_dword_2) * (b >> bits_in_dword_2);
+ return (r.all);
+}
+
+/* Returns: a * b */
+ti_int
+__multi3(ti_int a, ti_int b)
+{
+ twords x;
+ x.all = a;
+ twords y;
+ y.all = b;
+ twords r;
+ r.all = __mulddi3(x.s.low, y.s.low);
+ r.s.high += x.s.high * y.s.low + x.s.low * y.s.high;
+ return (r.all);
+}