1 # Test 32-bit COMPARE 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 14 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. 26 # 27 # CHECK: lb [[REG:%r[0-5]]], 0(%r3) 28 # CHECK: cr %r4, [[REG]] 29 # CHECK: jge [[LABEL:\.L[^ ]*]] 30 # CHECK: lb [[REG:%r[0-5]]], 1(%r3) 31 # CHECK: cr %r4, [[REG]] 32 # CHECK: jge [[LABEL]] 33 # CHECK: lb [[REG:%r[0-5]]], 2(%r3) 34 # CHECK: cr %r4, [[REG]] 35 # CHECK: jge [[LABEL]] 36 # CHECK: lb [[REG:%r[0-5]]], 3(%r3) 37 # CHECK: cr %r4, [[REG]] 38 # CHECK: jge [[LABEL]] 39 # CHECK: lb [[REG:%r[0-5]]], 4(%r3) 40 # CHECK: cr %r4, [[REG]] 41 # CHECK: jge [[LABEL]] 42 # CHECK: lb [[REG:%r[0-5]]], 5(%r3) 43 # CHECK: crje %r4, [[REG]], [[LABEL]] 44 # CHECK: lb [[REG:%r[0-5]]], 6(%r3) 45 # CHECK: crje %r4, [[REG]], [[LABEL]] 46 # CHECK: lb [[REG:%r[0-5]]], 7(%r3) 47 # CHECK: crje %r4, [[REG]], [[LABEL]] 48 # ...main goes here... 49 # CHECK: lb [[REG:%r[0-5]]], 25(%r3) 50 # CHECK: crje %r4, [[REG]], [[LABEL:\.L[^ ]*]] 51 # CHECK: lb [[REG:%r[0-5]]], 26(%r3) 52 # CHECK: crje %r4, [[REG]], [[LABEL]] 53 # CHECK: lb [[REG:%r[0-5]]], 27(%r3) 54 # CHECK: crje %r4, [[REG]], [[LABEL]] 55 # CHECK: lb [[REG:%r[0-5]]], 28(%r3) 56 # CHECK: crje %r4, [[REG]], [[LABEL]] 57 # CHECK: lb [[REG:%r[0-5]]], 29(%r3) 58 # CHECK: cr %r4, [[REG]] 59 # CHECK: jge [[LABEL]] 60 # CHECK: lb [[REG:%r[0-5]]], 30(%r3) 61 # CHECK: cr %r4, [[REG]] 62 # CHECK: jge [[LABEL]] 63 # CHECK: lb [[REG:%r[0-5]]], 31(%r3) 64 # CHECK: cr %r4, [[REG]] 65 # CHECK: jge [[LABEL]] 66 # CHECK: lb [[REG:%r[0-5]]], 32(%r3) 67 # CHECK: cr %r4, [[REG]] 68 # CHECK: jge [[LABEL]] 69 70 branch_blocks = 8 71 main_size = 0xffcc 72 73 print 'define void @f1(i8 *%base, i8 *%stop, i32 %limit) {' 74 print 'entry:' 75 print ' br label %before0' 76 print '' 77 78 for i in xrange(branch_blocks): 79 next = 'before%d' % (i + 1) if i + 1 < branch_blocks else 'main' 80 print 'before%d:' % i 81 print ' %%bstop%d = getelementptr i8, i8 *%%stop, i64 %d' % (i, i) 82 print ' %%bcur%d = load i8 , i8 *%%bstop%d' % (i, i) 83 print ' %%bext%d = sext i8 %%bcur%d to i32' % (i, i) 84 print ' %%btest%d = icmp eq i32 %%limit, %%bext%d' % (i, i) 85 print ' br i1 %%btest%d, label %%after0, label %%%s' % (i, next) 86 print '' 87 88 print '%s:' % next 89 a, b = 1, 1 90 for i in xrange(0, main_size, 6): 91 a, b = b, a + b 92 offset = 4096 + b % 500000 93 value = a % 256 94 print ' %%ptr%d = getelementptr i8, i8 *%%base, i64 %d' % (i, offset) 95 print ' store volatile i8 %d, i8 *%%ptr%d' % (value, i) 96 97 for i in xrange(branch_blocks): 98 print ' %%astop%d = getelementptr i8, i8 *%%stop, i64 %d' % (i, i + 25) 99 print ' %%acur%d = load i8 , i8 *%%astop%d' % (i, i) 100 print ' %%aext%d = sext i8 %%acur%d to i32' % (i, i) 101 print ' %%atest%d = icmp eq i32 %%limit, %%aext%d' % (i, i) 102 print ' br i1 %%atest%d, label %%main, label %%after%d' % (i, i) 103 print '' 104 print 'after%d:' % i 105 106 print ' ret void' 107 print '}' 108
