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1# Test 64-bit COMPARE IMMEDIATE AND BRANCH 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#   0xffcc 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 12 bytes if it uses a short
21# branch and 16 if it uses a long one.  The ones before "main:" have to
22# take the branch length into account, which is 6 for short branches,
23# so the final (0x34 - 6) / 12 == 3 blocks can use short branches.
24# The ones after "main:" do not, so the first 0x34 / 12 == 4 blocks
25# can use short branches.  The conservative algorithm we use makes
26# one of the forward branches unnecessarily long, as noted in the
27# check output below.
28#
29# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
30# CHECK: cghi [[REG]], 50
31# CHECK: jgl [[LABEL:\.L[^ ]*]]
32# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
33# CHECK: cghi [[REG]], 51
34# CHECK: jgl [[LABEL]]
35# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
36# CHECK: cghi [[REG]], 52
37# CHECK: jgl [[LABEL]]
38# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
39# CHECK: cghi [[REG]], 53
40# CHECK: jgl [[LABEL]]
41# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
42# CHECK: cghi [[REG]], 54
43# CHECK: jgl [[LABEL]]
44# ...as mentioned above, the next one could be a CGIJL instead...
45# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
46# CHECK: cghi [[REG]], 55
47# CHECK: jgl [[LABEL]]
48# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
49# CHECK: cgijl [[REG]], 56, [[LABEL]]
50# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
51# CHECK: cgijl [[REG]], 57, [[LABEL]]
52# ...main goes here...
53# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
54# CHECK: cgijl [[REG]], 100, [[LABEL:\.L[^ ]*]]
55# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
56# CHECK: cgijl [[REG]], 101, [[LABEL]]
57# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
58# CHECK: cgijl [[REG]], 102, [[LABEL]]
59# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
60# CHECK: cgijl [[REG]], 103, [[LABEL]]
61# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
62# CHECK: cghi [[REG]], 104
63# CHECK: jgl [[LABEL]]
64# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
65# CHECK: cghi [[REG]], 105
66# CHECK: jgl [[LABEL]]
67# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
68# CHECK: cghi [[REG]], 106
69# CHECK: jgl [[LABEL]]
70# CHECK: lgb [[REG:%r[0-5]]], 0(%r3)
71# CHECK: cghi [[REG]], 107
72# CHECK: jgl [[LABEL]]
73
74branch_blocks = 8
75main_size = 0xffcc
76
77print '@global = global i32 0'
78
79print 'define void @f1(i8 *%base, i8 *%stop) {'
80print 'entry:'
81print '  br label %before0'
82print ''
83
84for i in xrange(branch_blocks):
85    next = 'before%d' % (i + 1) if i + 1 < branch_blocks else 'main'
86    print 'before%d:' % i
87    print '  %%bcur%d = load i8 , i8 *%%stop' % i
88    print '  %%bext%d = sext i8 %%bcur%d to i64' % (i, i)
89    print '  %%btest%d = icmp slt i64 %%bext%d, %d' % (i, i, i + 50)
90    print '  br i1 %%btest%d, label %%after0, label %%%s' % (i, next)
91    print ''
92
93print '%s:' % next
94a, b = 1, 1
95for i in xrange(0, main_size, 6):
96    a, b = b, a + b
97    offset = 4096 + b % 500000
98    value = a % 256
99    print '  %%ptr%d = getelementptr i8, i8 *%%base, i64 %d' % (i, offset)
100    print '  store volatile i8 %d, i8 *%%ptr%d' % (value, i)
101
102for i in xrange(branch_blocks):
103    print '  %%acur%d = load i8 , i8 *%%stop' % i
104    print '  %%aext%d = sext i8 %%acur%d to i64' % (i, i)
105    print '  %%atest%d = icmp slt i64 %%aext%d, %d' % (i, i, i + 100)
106    print '  br i1 %%atest%d, label %%main, label %%after%d' % (i, i)
107    print ''
108    print 'after%d:' % i
109
110print '  %dummy = load volatile i32, i32 *@global'
111print '  ret void'
112print '}'
113