1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
|
# *****************************************************************
#
# The Compcert verified compiler
#
# Xavier Leroy, INRIA Paris
#
# Copyright (c) 2016 Institut National de Recherche en Informatique et
# en Automatique.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
# * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# * Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
# * Neither the name of the <organization> nor the
# names of its contributors may be used to endorse or promote products
# derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT
# HOLDER> BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
# EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
# PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
# LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
# NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
# *********************************************************************
# Helper functions for 64-bit integer arithmetic. PowerPC version.
.text
# Unsigned multiply high
# Reference C implementation in ../c/i64_umul.c
.balign 16
.globl __i64_umulh
__i64_umulh:
# u1 in r3; u0 in r4; v1 in r5; v0 in r6
mulhwu r0, r4, r6 # k (in r0) = high((u64) u0 * (u64) v0)
mullw r8, r3, r6
mulhwu r7, r3, r6 # t (in r8:r7) = (u64) u1 * (u64) v0
addc r0, r8, r0 # w1 (in r0) = low (t + k)
addze r9, r7 # w2 (in r9) = high (t + k)
mullw r8, r4, r5
mulhwu r7, r4, r5 # t (in r8:r7) = (u64) u0 * (u64) v1
addc r0, r8, r0 # tmp (in r0) = low (t + w1)
addze r0, r7 # k (in r0) = high(t + w1)
mullw r8, r3, r5
mulhwu r7, r3, r5 # t (in r8:r7) = (u64) u1 * (u64) v1
addc r4, r8, r9 # add w2
addze r3, r7
addc r4, r4, r0 # add k
addze r3, r3
blr
.type __i64_umulh, @function
.size __i64_umulh, .-__i64_umulh
|
