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 70from __future__ import print_function 71 72branch_blocks = 10 73main_size = 0xffd8 74 75print('@global = global i32 0') 76 77print('define void @f1(i8 *%base, i32 *%stop, i32 %limit) {') 78print('entry:') 79print(' br label %before0') 80print('') 81 82for i in range(branch_blocks): 83 next = 'before%d' % (i + 1) if i + 1 < branch_blocks else 'main' 84 print('before%d:' % i) 85 print(' %%bstop%d = getelementptr i32, i32 *%%stop, i64 %d' % (i, i)) 86 print(' %%bcur%d = load i32 , i32 *%%bstop%d' % (i, i)) 87 print(' %%btest%d = icmp eq i32 %%limit, %%bcur%d' % (i, i)) 88 print(' br i1 %%btest%d, label %%after0, label %%%s' % (i, next)) 89 print('') 90 91print('%s:' % next) 92a, b = 1, 1 93for i in range(0, main_size, 6): 94 a, b = b, a + b 95 offset = 4096 + b % 500000 96 value = a % 256 97 print(' %%ptr%d = getelementptr i8, i8 *%%base, i64 %d' % (i, offset)) 98 print(' store volatile i8 %d, i8 *%%ptr%d' % (value, i)) 99 100for i in range(branch_blocks): 101 print(' %%astop%d = getelementptr i32, i32 *%%stop, i64 %d' % (i, i + 25)) 102 print(' %%acur%d = load i32 , i32 *%%astop%d' % (i, i)) 103 print(' %%atest%d = icmp eq i32 %%limit, %%acur%d' % (i, i)) 104 print(' br i1 %%atest%d, label %%main, label %%after%d' % (i, i)) 105 print('') 106 print('after%d:' % i) 107 108print(' %dummy = load volatile i32, i32 *@global') 109print(' ret void') 110print('}') 111