1
2#!/usr/bin/env python
3
4# Auto-generates an exhaustive and repetitive test for correct bundle-locked
5# alignment on x86.
6# For every possible offset in an aligned bundle, a bundle-locked group of every
7# size in the inclusive range [1, bundle_size] is inserted. An appropriate CHECK
8# is added to verify that NOP padding occurred (or did not occur) as expected.
9# Run with --align-to-end to generate a similar test with align_to_end for each
10# .bundle_lock directive.
11
12# This script runs with Python 2.7 and 3.2+
13
14from __future__ import print_function
15import argparse
16
17BUNDLE_SIZE_POW2 = 4
18BUNDLE_SIZE = 2 ** BUNDLE_SIZE_POW2
19
20PREAMBLE = '''
21# RUN: llvm-mc -filetype=obj -triple i386-pc-linux-gnu %s -o - \\
22# RUN:   | llvm-objdump -triple i386 -disassemble -no-show-raw-insn - | FileCheck %s
23
24# !!! This test is auto-generated from utils/testgen/mc-bundling-x86-gen.py !!!
25#     It tests that bundle-aligned grouping works correctly in MC. Read the
26#     source of the script for more details.
27
28  .text
29  .bundle_align_mode {0}
30'''.format(BUNDLE_SIZE_POW2).lstrip()
31
32ALIGNTO = '  .align {0}, 0x90'
33NOPFILL = '  .fill {0}, 1, 0x90'
34
35def print_bundle_locked_sequence(len, align_to_end=False):
36  print('  .bundle_lock{0}'.format(' align_to_end' if align_to_end else ''))
37  print('  .rept {0}'.format(len))
38  print('  inc %eax')
39  print('  .endr')
40  print('  .bundle_unlock')
41
42def generate(align_to_end=False):
43  print(PREAMBLE)
44
45  ntest = 0
46  for instlen in range(1, BUNDLE_SIZE + 1):
47    for offset in range(0, BUNDLE_SIZE):
48      # Spread out all the instructions to not worry about cross-bundle
49      # interference.
50      print(ALIGNTO.format(2 * BUNDLE_SIZE))
51      print('INSTRLEN_{0}_OFFSET_{1}:'.format(instlen, offset))
52      if offset > 0:
53        print(NOPFILL.format(offset))
54      print_bundle_locked_sequence(instlen, align_to_end)
55
56      # Now generate an appropriate CHECK line
57      base_offset = ntest * 2 * BUNDLE_SIZE
58      inst_orig_offset = base_offset + offset  # had it not been padded...
59
60      def print_check(adjusted_offset=None, nop_split_offset=None):
61        if adjusted_offset is not None:
62          print('# CHECK: {0:x}: nop'.format(inst_orig_offset))
63          if nop_split_offset is not None:
64            print('# CHECK: {0:x}: nop'.format(nop_split_offset))
65          print('# CHECK: {0:x}: incl'.format(adjusted_offset))
66        else:
67          print('# CHECK: {0:x}: incl'.format(inst_orig_offset))
68
69      if align_to_end:
70        if offset + instlen == BUNDLE_SIZE:
71          # No padding needed
72          print_check()
73        elif offset + instlen < BUNDLE_SIZE:
74          # Pad to end at nearest bundle boundary
75          offset_to_end = base_offset + (BUNDLE_SIZE - instlen)
76          print_check(offset_to_end)
77        else: # offset + instlen > BUNDLE_SIZE
78          # Pad to end at next bundle boundary, splitting the nop sequence
79          # at the nearest bundle boundary
80          offset_to_nearest_bundle = base_offset + BUNDLE_SIZE
81          offset_to_end = base_offset + (BUNDLE_SIZE * 2 - instlen)
82          if offset_to_nearest_bundle == offset_to_end:
83            offset_to_nearest_bundle = None
84          print_check(offset_to_end, offset_to_nearest_bundle)
85      else:
86        if offset + instlen > BUNDLE_SIZE:
87          # Padding needed
88          aligned_offset = (inst_orig_offset + instlen) & ~(BUNDLE_SIZE - 1)
89          print_check(aligned_offset)
90        else:
91          # No padding needed
92          print_check()
93
94      print()
95      ntest += 1
96
97if __name__ == '__main__':
98  argparser = argparse.ArgumentParser()
99  argparser.add_argument('--align-to-end',
100                         action='store_true',
101                         help='generate .bundle_lock with align_to_end option')
102  args = argparser.parse_args()
103  generate(align_to_end=args.align_to_end)
104