1// Copyright 2014, VIXL authors
2// All rights reserved.
3//
4// Redistribution and use in source and binary forms, with or without
5// modification, are permitted provided that the following conditions are met:
6//
7//   * Redistributions of source code must retain the above copyright notice,
8//     this list of conditions and the following disclaimer.
9//   * Redistributions in binary form must reproduce the above copyright notice,
10//     this list of conditions and the following disclaimer in the documentation
11//     and/or other materials provided with the distribution.
12//   * Neither the name of ARM Limited nor the names of its contributors may be
13//     used to endorse or promote products derived from this software without
14//     specific prior written permission.
15//
16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS CONTRIBUTORS "AS IS" AND
17// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
20// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
23// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
25// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26
27#include <cstdlib>
28#include <string>
29
30#include "test-runner.h"
31
32#include "aarch64/decoder-aarch64.h"
33#include "aarch64/disasm-aarch64.h"
34
35#define TEST(name) TEST_(AARCH64_FUZZ_##name)
36
37
38namespace vixl {
39namespace aarch64 {
40
41static void FuzzHelper(std::string mode, int step_size, int offset, int shift) {
42  Decoder decoder;
43  PrintDisassembler disasm(stdout);
44  Instruction buffer[kInstructionSize];
45
46  if (mode == "disasm") {
47    decoder.AppendVisitor(&disasm);
48  } else {
49    VIXL_CHECK(mode == "decoder");
50  }
51
52  for (uint64_t i = offset << shift; i < (UINT64_C(1) << 32); i += step_size) {
53    buffer->SetInstructionBits(static_cast<uint32_t>(i));
54    decoder.Decode(buffer);
55  }
56}
57
58// Number of shards used to split fuzz tests. This value isn't used in the macro
59// below, so if you change this, ensure more FUZZ_SHARD instances are
60// instantiated.
61static const int kShardCount = 16;
62
63// Test approximately 1% of the instruction space for the decoder, and 0.2% for
64// the disassembler. Multiply the step size by the number of shards issued.
65static const int kDecoderStep = 100 * kShardCount + 1;
66static const int kDisasmStep = 500 * kShardCount + 1;
67
68// Shift the offset argument into the top-level opcode bits, which helps to
69// spread the fuzz coverage across instruction classes.
70static const int kOpFieldShift = 25;
71
72#define FUZZ_SHARD(mode, step, i, shift) \
73  TEST(mode##_##i) { FuzzHelper(#mode, step, i, shift); }
74
75FUZZ_SHARD(decoder, kDecoderStep, 0, kOpFieldShift)
76FUZZ_SHARD(decoder, kDecoderStep, 1, kOpFieldShift)
77FUZZ_SHARD(decoder, kDecoderStep, 2, kOpFieldShift)
78FUZZ_SHARD(decoder, kDecoderStep, 3, kOpFieldShift)
79FUZZ_SHARD(decoder, kDecoderStep, 4, kOpFieldShift)
80FUZZ_SHARD(decoder, kDecoderStep, 5, kOpFieldShift)
81FUZZ_SHARD(decoder, kDecoderStep, 6, kOpFieldShift)
82FUZZ_SHARD(decoder, kDecoderStep, 7, kOpFieldShift)
83FUZZ_SHARD(decoder, kDecoderStep, 8, kOpFieldShift)
84FUZZ_SHARD(decoder, kDecoderStep, 9, kOpFieldShift)
85FUZZ_SHARD(decoder, kDecoderStep, 10, kOpFieldShift)
86FUZZ_SHARD(decoder, kDecoderStep, 11, kOpFieldShift)
87FUZZ_SHARD(decoder, kDecoderStep, 12, kOpFieldShift)
88FUZZ_SHARD(decoder, kDecoderStep, 13, kOpFieldShift)
89FUZZ_SHARD(decoder, kDecoderStep, 14, kOpFieldShift)
90FUZZ_SHARD(decoder, kDecoderStep, 15, kOpFieldShift)
91
92FUZZ_SHARD(disasm, kDisasmStep, 0, kOpFieldShift)
93FUZZ_SHARD(disasm, kDisasmStep, 1, kOpFieldShift)
94FUZZ_SHARD(disasm, kDisasmStep, 2, kOpFieldShift)
95FUZZ_SHARD(disasm, kDisasmStep, 3, kOpFieldShift)
96FUZZ_SHARD(disasm, kDisasmStep, 4, kOpFieldShift)
97FUZZ_SHARD(disasm, kDisasmStep, 5, kOpFieldShift)
98FUZZ_SHARD(disasm, kDisasmStep, 6, kOpFieldShift)
99FUZZ_SHARD(disasm, kDisasmStep, 7, kOpFieldShift)
100FUZZ_SHARD(disasm, kDisasmStep, 8, kOpFieldShift)
101FUZZ_SHARD(disasm, kDisasmStep, 9, kOpFieldShift)
102FUZZ_SHARD(disasm, kDisasmStep, 10, kOpFieldShift)
103FUZZ_SHARD(disasm, kDisasmStep, 11, kOpFieldShift)
104FUZZ_SHARD(disasm, kDisasmStep, 12, kOpFieldShift)
105FUZZ_SHARD(disasm, kDisasmStep, 13, kOpFieldShift)
106FUZZ_SHARD(disasm, kDisasmStep, 14, kOpFieldShift)
107FUZZ_SHARD(disasm, kDisasmStep, 15, kOpFieldShift)
108
109}  // namespace aarch64
110}  // namespace vixl
111