xref: /llvm-project/llvm/test/CodeGen/SystemZ/Large/branch-range-11.py (revision b71edfaa4ec3c998aadb35255ce2f60bba2940b0)
1# Test 32-bit COMPARE LOGICAL IMMEDIATE AND BRANCH in cases where the sheer
2# number of 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#   0xffc6 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 14 bytes if it uses a short
21# branch and 20 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 (0x3a - 6) / 14 == 3 blocks can use short branches.
24# The ones after "main:" do not, so the first 0x3a / 14 == 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: l [[REG:%r[0-5]]], 0(%r3)
30# CHECK: s [[REG]], 0(%r4)
31# CHECK: clfi [[REG]], 50
32# CHECK: jgl [[LABEL:\.L[^ ]*]]
33# CHECK: l [[REG:%r[0-5]]], 0(%r3)
34# CHECK: s [[REG]], 0(%r4)
35# CHECK: clfi [[REG]], 51
36# CHECK: jgl [[LABEL]]
37# CHECK: l [[REG:%r[0-5]]], 0(%r3)
38# CHECK: s [[REG]], 0(%r4)
39# CHECK: clfi [[REG]], 52
40# CHECK: jgl [[LABEL]]
41# CHECK: l [[REG:%r[0-5]]], 0(%r3)
42# CHECK: s [[REG]], 0(%r4)
43# CHECK: clfi [[REG]], 53
44# CHECK: jgl [[LABEL]]
45# CHECK: l [[REG:%r[0-5]]], 0(%r3)
46# CHECK: s [[REG]], 0(%r4)
47# CHECK: clfi [[REG]], 54
48# CHECK: jgl [[LABEL]]
49# ...as mentioned above, the next one could be a CLIJL instead...
50# CHECK: l [[REG:%r[0-5]]], 0(%r3)
51# CHECK: s [[REG]], 0(%r4)
52# CHECK: clfi [[REG]], 55
53# CHECK: jgl [[LABEL]]
54# CHECK: l [[REG:%r[0-5]]], 0(%r3)
55# CHECK: s [[REG]], 0(%r4)
56# CHECK: clijl [[REG]], 56, [[LABEL]]
57# CHECK: l [[REG:%r[0-5]]], 0(%r3)
58# CHECK: s [[REG]], 0(%r4)
59# CHECK: clijl [[REG]], 57, [[LABEL]]
60# ...main goes here...
61# CHECK: l [[REG:%r[0-5]]], 0(%r3)
62# CHECK: s [[REG]], 0(%r4)
63# CHECK: clijl [[REG]], 100, [[LABEL:\.L[^ ]*]]
64# CHECK: l [[REG:%r[0-5]]], 0(%r3)
65# CHECK: s [[REG]], 0(%r4)
66# CHECK: clijl [[REG]], 101, [[LABEL]]
67# CHECK: l [[REG:%r[0-5]]], 0(%r3)
68# CHECK: s [[REG]], 0(%r4)
69# CHECK: clijl [[REG]], 102, [[LABEL]]
70# CHECK: l [[REG:%r[0-5]]], 0(%r3)
71# CHECK: s [[REG]], 0(%r4)
72# CHECK: clijl [[REG]], 103, [[LABEL]]
73# CHECK: l [[REG:%r[0-5]]], 0(%r3)
74# CHECK: s [[REG]], 0(%r4)
75# CHECK: clfi [[REG]], 104
76# CHECK: jgl [[LABEL]]
77# CHECK: l [[REG:%r[0-5]]], 0(%r3)
78# CHECK: s [[REG]], 0(%r4)
79# CHECK: clfi [[REG]], 105
80# CHECK: jgl [[LABEL]]
81# CHECK: l [[REG:%r[0-5]]], 0(%r3)
82# CHECK: s [[REG]], 0(%r4)
83# CHECK: clfi [[REG]], 106
84# CHECK: jgl [[LABEL]]
85# CHECK: l [[REG:%r[0-5]]], 0(%r3)
86# CHECK: s [[REG]], 0(%r4)
87# CHECK: clfi [[REG]], 107
88# CHECK: jgl [[LABEL]]
89
90from __future__ import print_function
91
92branch_blocks = 8
93main_size = 0xFFC6
94
95print("@global = global i32 0")
96
97print("define void @f1(i8 *%base, i32 *%stopa, i32 *%stopb) {")
98print("entry:")
99print("  br label %before0")
100print("")
101
102for i in range(branch_blocks):
103    next = "before%d" % (i + 1) if i + 1 < branch_blocks else "main"
104    print("before%d:" % i)
105    print("  %%bcur%da = load i32 , i32 *%%stopa" % i)
106    print("  %%bcur%db = load i32 , i32 *%%stopb" % i)
107    print("  %%bsub%d = sub i32 %%bcur%da, %%bcur%db" % (i, i, i))
108    print("  %%btest%d = icmp ult i32 %%bsub%d, %d" % (i, i, i + 50))
109    print("  br i1 %%btest%d, label %%after0, label %%%s" % (i, next))
110    print("")
111
112print("%s:" % next)
113a, b = 1, 1
114for i in range(0, main_size, 6):
115    a, b = b, a + b
116    offset = 4096 + b % 500000
117    value = a % 256
118    print("  %%ptr%d = getelementptr i8, i8 *%%base, i64 %d" % (i, offset))
119    print("  store volatile i8 %d, i8 *%%ptr%d" % (value, i))
120
121for i in range(branch_blocks):
122    print("  %%acur%da = load i32 , i32 *%%stopa" % i)
123    print("  %%acur%db = load i32 , i32 *%%stopb" % i)
124    print("  %%asub%d = sub i32 %%acur%da, %%acur%db" % (i, i, i))
125    print("  %%atest%d = icmp ult i32 %%asub%d, %d" % (i, i, i + 100))
126    print("  br i1 %%atest%d, label %%main, label %%after%d" % (i, i))
127    print("")
128    print("after%d:" % i)
129
130print("  %dummy = load volatile i32, i32 *@global")
131print("  ret void")
132print("}")
133