| # Test normal conditional branches in cases where the sheer number of |
| # instructions causes some branches to be out of range. |
| # RUN: %python %s | llc -mtriple=s390x-linux-gnu | FileCheck %s |
| |
| # Construct: |
| # |
| # before0: |
| # conditional branch to after0 |
| # ... |
| # beforeN: |
| # conditional branch to after0 |
| # main: |
| # 0xffd8 bytes, from MVIY instructions |
| # conditional branch to main |
| # after0: |
| # ... |
| # conditional branch to main |
| # afterN: |
| # |
| # Each conditional branch sequence occupies 8 bytes if it uses a short branch |
| # and 10 if it uses a long one. The ones before "main:" have to take the branch |
| # length into account -- which is 4 bytes for short branches -- so the final |
| # (0x28 - 4) / 8 == 4 blocks can use short branches. The ones after "main:" |
| # do not, so the first 0x28 / 8 == 5 can use short branches. However, |
| # the conservative algorithm we use makes one branch unnecessarily long |
| # on each side. |
| # |
| # CHECK: c %r4, 0(%r3) |
| # CHECK: jge [[LABEL:\.L[^ ]*]] |
| # CHECK: c %r4, 4(%r3) |
| # CHECK: jge [[LABEL]] |
| # CHECK: c %r4, 8(%r3) |
| # CHECK: jge [[LABEL]] |
| # CHECK: c %r4, 12(%r3) |
| # CHECK: jge [[LABEL]] |
| # CHECK: c %r4, 16(%r3) |
| # CHECK: jge [[LABEL]] |
| # CHECK: c %r4, 20(%r3) |
| # CHECK: jge [[LABEL]] |
| # CHECK: c %r4, 24(%r3) |
| # CHECK: j{{g?}}e [[LABEL]] |
| # CHECK: c %r4, 28(%r3) |
| # CHECK: je [[LABEL]] |
| # CHECK: c %r4, 32(%r3) |
| # CHECK: je [[LABEL]] |
| # CHECK: c %r4, 36(%r3) |
| # CHECK: je [[LABEL]] |
| # ...main goes here... |
| # CHECK: c %r4, 100(%r3) |
| # CHECK: je [[LABEL:\.L[^ ]*]] |
| # CHECK: c %r4, 104(%r3) |
| # CHECK: je [[LABEL]] |
| # CHECK: c %r4, 108(%r3) |
| # CHECK: je [[LABEL]] |
| # CHECK: c %r4, 112(%r3) |
| # CHECK: je [[LABEL]] |
| # CHECK: c %r4, 116(%r3) |
| # CHECK: j{{g?}}e [[LABEL]] |
| # CHECK: c %r4, 120(%r3) |
| # CHECK: jge [[LABEL]] |
| # CHECK: c %r4, 124(%r3) |
| # CHECK: jge [[LABEL]] |
| # CHECK: c %r4, 128(%r3) |
| # CHECK: jge [[LABEL]] |
| # CHECK: c %r4, 132(%r3) |
| # CHECK: jge [[LABEL]] |
| # CHECK: c %r4, 136(%r3) |
| # CHECK: jge [[LABEL]] |
| |
| from __future__ import print_function |
| |
| branch_blocks = 10 |
| main_size = 0xffd8 |
| |
| print('@global = global i32 0') |
| |
| print('define void @f1(i8 *%base, i32 *%stop, i32 %limit) {') |
| print('entry:') |
| print(' br label %before0') |
| print('') |
| |
| for i in range(branch_blocks): |
| next = 'before%d' % (i + 1) if i + 1 < branch_blocks else 'main' |
| print('before%d:' % i) |
| print(' %%bstop%d = getelementptr i32, i32 *%%stop, i64 %d' % (i, i)) |
| print(' %%bcur%d = load i32 , i32 *%%bstop%d' % (i, i)) |
| print(' %%btest%d = icmp eq i32 %%limit, %%bcur%d' % (i, i)) |
| print(' br i1 %%btest%d, label %%after0, label %%%s' % (i, next)) |
| print('') |
| |
| print('%s:' % next) |
| a, b = 1, 1 |
| for i in range(0, main_size, 6): |
| a, b = b, a + b |
| offset = 4096 + b % 500000 |
| value = a % 256 |
| print(' %%ptr%d = getelementptr i8, i8 *%%base, i64 %d' % (i, offset)) |
| print(' store volatile i8 %d, i8 *%%ptr%d' % (value, i)) |
| |
| for i in range(branch_blocks): |
| print(' %%astop%d = getelementptr i32, i32 *%%stop, i64 %d' % (i, i + 25)) |
| print(' %%acur%d = load i32 , i32 *%%astop%d' % (i, i)) |
| print(' %%atest%d = icmp eq i32 %%limit, %%acur%d' % (i, i)) |
| print(' br i1 %%atest%d, label %%main, label %%after%d' % (i, i)) |
| print('') |
| print('after%d:' % i) |
| |
| print(' %dummy = load volatile i32, i32 *@global') |
| print(' ret void') |
| print('}') |