1# Test normal conditional branches in cases where the sheer number of
2# instructions causes some branches to be out of range.
3# RUN: python %s | llc -mtriple=s390x-linux-gnu | FileCheck %s
4
5# Construct:
6#
7# before0:
8#   conditional branch to after0
9#   ...
10# beforeN:
11#   conditional branch to after0
12# main:
13#   0xffd8 bytes, from MVIY instructions
14#   conditional branch to main
15# after0:
16#   ...
17#   conditional branch to main
18# afterN:
19#
20# Each conditional branch sequence occupies 8 bytes if it uses a short branch
21# and 10 if it uses a long one.  The ones before "main:" have to take the branch
22# length into account -- which is 4 bytes for short branches -- so the final
23# (0x28 - 4) / 8 == 4 blocks can use short branches.  The ones after "main:"
24# do not, so the first 0x28 / 8 == 5 can use short branches.  However,
25# the conservative algorithm we use makes one branch unnecessarily long
26# on each side.
27#
28# CHECK: c %r4, 0(%r3)
29# CHECK: jge [[LABEL:\.L[^ ]*]]
30# CHECK: c %r4, 4(%r3)
31# CHECK: jge [[LABEL]]
32# CHECK: c %r4, 8(%r3)
33# CHECK: jge [[LABEL]]
34# CHECK: c %r4, 12(%r3)
35# CHECK: jge [[LABEL]]
36# CHECK: c %r4, 16(%r3)
37# CHECK: jge [[LABEL]]
38# CHECK: c %r4, 20(%r3)
39# CHECK: jge [[LABEL]]
40# CHECK: c %r4, 24(%r3)
41# CHECK: j{{g?}}e [[LABEL]]
42# CHECK: c %r4, 28(%r3)
43# CHECK: je [[LABEL]]
44# CHECK: c %r4, 32(%r3)
45# CHECK: je [[LABEL]]
46# CHECK: c %r4, 36(%r3)
47# CHECK: je [[LABEL]]
48# ...main goes here...
49# CHECK: c %r4, 100(%r3)
50# CHECK: je [[LABEL:\.L[^ ]*]]
51# CHECK: c %r4, 104(%r3)
52# CHECK: je [[LABEL]]
53# CHECK: c %r4, 108(%r3)
54# CHECK: je [[LABEL]]
55# CHECK: c %r4, 112(%r3)
56# CHECK: je [[LABEL]]
57# CHECK: c %r4, 116(%r3)
58# CHECK: j{{g?}}e [[LABEL]]
59# CHECK: c %r4, 120(%r3)
60# CHECK: jge [[LABEL]]
61# CHECK: c %r4, 124(%r3)
62# CHECK: jge [[LABEL]]
63# CHECK: c %r4, 128(%r3)
64# CHECK: jge [[LABEL]]
65# CHECK: c %r4, 132(%r3)
66# CHECK: jge [[LABEL]]
67# CHECK: c %r4, 136(%r3)
68# CHECK: jge [[LABEL]]
69
70branch_blocks = 10
71main_size = 0xffd8
72
73print '@global = global i32 0'
74
75print 'define void @f1(i8 *%base, i32 *%stop, i32 %limit) {'
76print 'entry:'
77print '  br label %before0'
78print ''
79
80for i in xrange(branch_blocks):
81    next = 'before%d' % (i + 1) if i + 1 < branch_blocks else 'main'
82    print 'before%d:' % i
83    print '  %%bstop%d = getelementptr i32, i32 *%%stop, i64 %d' % (i, i)
84    print '  %%bcur%d = load i32 , i32 *%%bstop%d' % (i, i)
85    print '  %%btest%d = icmp eq i32 %%limit, %%bcur%d' % (i, i)
86    print '  br i1 %%btest%d, label %%after0, label %%%s' % (i, next)
87    print ''
88
89print '%s:' % next
90a, b = 1, 1
91for i in xrange(0, main_size, 6):
92    a, b = b, a + b
93    offset = 4096 + b % 500000
94    value = a % 256
95    print '  %%ptr%d = getelementptr i8, i8 *%%base, i64 %d' % (i, offset)
96    print '  store volatile i8 %d, i8 *%%ptr%d' % (value, i)
97
98for i in xrange(branch_blocks):
99    print '  %%astop%d = getelementptr i32, i32 *%%stop, i64 %d' % (i, i + 25)
100    print '  %%acur%d = load i32 , i32 *%%astop%d' % (i, i)
101    print '  %%atest%d = icmp eq i32 %%limit, %%acur%d' % (i, i)
102    print '  br i1 %%atest%d, label %%main, label %%after%d' % (i, i)
103    print ''
104    print 'after%d:' % i
105
106print '  %dummy = load volatile i32, i32 *@global'
107print '  ret void'
108print '}'
109