ia64/linux-2.6.18-xen.hg

view arch/s390/math-emu/qrnnd.S @ 452:c7ed6fe5dca0

kexec: dont initialise regions in reserve_memory()

There is no need to initialise efi_memmap_res and boot_param_res in
reserve_memory() for the initial xen domain as it is done in
machine_kexec_setup_resources() using values from the kexec hypercall.

Signed-off-by: Simon Horman <horms@verge.net.au>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Feb 28 10:55:18 2008 +0000 (2008-02-28)
parents 831230e53067
children
line source
1 # S/390 __udiv_qrnnd
3 # r2 : &__r
4 # r3 : upper half of 64 bit word n
5 # r4 : lower half of 64 bit word n
6 # r5 : divisor d
7 # the reminder r of the division is to be stored to &__r and
8 # the quotient q is to be returned
10 .text
11 .globl __udiv_qrnnd
12 __udiv_qrnnd:
13 st %r2,24(%r15) # store pointer to reminder for later
14 lr %r0,%r3 # reload n
15 lr %r1,%r4
16 ltr %r2,%r5 # reload and test divisor
17 jp 5f
18 # divisor >= 0x80000000
19 srdl %r0,2 # n/4
20 srl %r2,1 # d/2
21 slr %r1,%r2 # special case if last bit of d is set
22 brc 3,0f # (n/4) div (n/2) can overflow by 1
23 ahi %r0,-1 # trick: subtract n/2, then divide
24 0: dr %r0,%r2 # signed division
25 ahi %r1,1 # trick part 2: add 1 to the quotient
26 # now (n >> 2) = (d >> 1) * %r1 + %r0
27 lhi %r3,1
28 nr %r3,%r1 # test last bit of q
29 jz 1f
30 alr %r0,%r2 # add (d>>1) to r
31 1: srl %r1,1 # q >>= 1
32 # now (n >> 2) = (d&-2) * %r1 + %r0
33 lhi %r3,1
34 nr %r3,%r5 # test last bit of d
35 jz 2f
36 slr %r0,%r1 # r -= q
37 brc 3,2f # borrow ?
38 alr %r0,%r5 # r += d
39 ahi %r1,-1
40 2: # now (n >> 2) = d * %r1 + %r0
41 alr %r1,%r1 # q <<= 1
42 alr %r0,%r0 # r <<= 1
43 brc 12,3f # overflow on r ?
44 slr %r0,%r5 # r -= d
45 ahi %r1,1 # q += 1
46 3: lhi %r3,2
47 nr %r3,%r4 # test next to last bit of n
48 jz 4f
49 ahi %r0,1 # r += 1
50 4: clr %r0,%r5 # r >= d ?
51 jl 6f
52 slr %r0,%r5 # r -= d
53 ahi %r1,1 # q += 1
54 # now (n >> 1) = d * %r1 + %r0
55 j 6f
56 5: # divisor < 0x80000000
57 srdl %r0,1
58 dr %r0,%r2 # signed division
59 # now (n >> 1) = d * %r1 + %r0
60 6: alr %r1,%r1 # q <<= 1
61 alr %r0,%r0 # r <<= 1
62 brc 12,7f # overflow on r ?
63 slr %r0,%r5 # r -= d
64 ahi %r1,1 # q += 1
65 7: lhi %r3,1
66 nr %r3,%r4 # isolate last bit of n
67 alr %r0,%r3 # r += (n & 1)
68 clr %r0,%r5 # r >= d ?
69 jl 8f
70 slr %r0,%r5 # r -= d
71 ahi %r1,1 # q += 1
72 8: # now n = d * %r1 + %r0
73 l %r2,24(%r15)
74 st %r0,0(%r2)
75 lr %r2,%r1
76 br %r14
77 .end __udiv_qrnnd