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
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
|
# *****************************************************************
#
# The Compcert verified compiler
#
# Xavier Leroy, INRIA Paris-Rocquencourt
#
# Copyright (c) 2013 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 64 version.
.text
### Conversion from unsigned long to double float
.balign 16
.globl __compcert_i64_utod
__compcert_i64_utod:
rldicl r3, r3, 0, 32 # clear top 32 bits
rldicl r4, r4, 0, 32 # clear top 32 bits
lis r5, 0x4f80 # 0x4f80_0000 = 2^32 in binary32 format
stdu r3, -32(r1)
std r4, 8(r1)
stw r5, 16(r1)
lfd f1, 0(r1) # high 32 bits of argument
lfd f2, 8(r1) # low 32 bits of argument
lfs f3, 16(r1) # 2^32
fcfid f1, f1 # convert both 32-bit halves to FP (exactly)
fcfid f2, f2
fmadd f1, f1, f3, f2 # compute hi * 2^32 + lo
addi r1, r1, 32
blr
.type __compcert_i64_utod, @function
.size __compcert_i64_utod, .-__compcert_i64_utod
# Alternate implementation using round-to-odd:
# rldimi r4, r3, 32, 0 # reassemble (r3,r4) as a 64-bit integer in r4
# cmpdi r4, 0 # is r4 >= 2^63 ?
# blt 1f
# stdu r4, -16(r1) # r4 < 2^63: convert as signed
# lfd f1, 0(r1)
# fcfid f1, f1
# addi r1, r1, 16
# blr
#1: rldicl r0, r4, 0, 63 # extract low bit of r4
# srdi r4, r4, 1
# or r4, r4, r0 # round r4 to 63 bits, using round-to-odd
# stdu r4, -16(r1) # convert to binary64
# lfd f1, 0(r1)
# fcfid f1, f1
# fadd f1, f1, f1 # multiply result by 2
# addi r1, r1, 16
# blr
|
