1 /*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "linker/relative_patcher_test.h"
18 #include "linker/mips/relative_patcher_mips.h"
19
20 namespace art {
21 namespace linker {
22
23 // We'll maximize the range of a single load instruction for dex cache array accesses
24 // by aligning offset -32768 with the offset of the first used element.
25 static constexpr uint32_t kDexCacheArrayLwOffset = 0x8000;
26
27 class MipsRelativePatcherTest : public RelativePatcherTest {
28 public:
MipsRelativePatcherTest()29 MipsRelativePatcherTest() : RelativePatcherTest(kMips, "mips32r2") {}
30
31 protected:
32 static const uint8_t kUnpatchedPcRelativeRawCode[];
33 static const uint32_t kLiteralOffset;
34 static const uint32_t kAnchorOffset;
35 static const ArrayRef<const uint8_t> kUnpatchedPcRelativeCode;
36
GetMethodOffset(uint32_t method_idx)37 uint32_t GetMethodOffset(uint32_t method_idx) {
38 auto result = method_offset_map_.FindMethodOffset(MethodRef(method_idx));
39 CHECK(result.first);
40 return result.second;
41 }
42
43 void CheckPcRelativePatch(const ArrayRef<const LinkerPatch>& patches, uint32_t target_offset);
44 void TestDexCacheReference(uint32_t dex_cache_arrays_begin, uint32_t element_offset);
45 void TestStringReference(uint32_t string_offset);
46 };
47
48 const uint8_t MipsRelativePatcherTest::kUnpatchedPcRelativeRawCode[] = {
49 0x00, 0x00, 0x10, 0x04, // nal
50 0x34, 0x12, 0x12, 0x3C, // lui s2, high(diff); placeholder = 0x1234
51 0x21, 0x90, 0x5F, 0x02, // addu s2, s2, ra
52 0x78, 0x56, 0x52, 0x26, // addiu s2, s2, low(diff); placeholder = 0x5678
53 };
54 const uint32_t MipsRelativePatcherTest::kLiteralOffset = 4; // At lui (where patching starts).
55 const uint32_t MipsRelativePatcherTest::kAnchorOffset = 8; // At addu (where PC+0 points).
56 const ArrayRef<const uint8_t> MipsRelativePatcherTest::kUnpatchedPcRelativeCode(
57 kUnpatchedPcRelativeRawCode);
58
CheckPcRelativePatch(const ArrayRef<const LinkerPatch> & patches,uint32_t target_offset)59 void MipsRelativePatcherTest::CheckPcRelativePatch(const ArrayRef<const LinkerPatch>& patches,
60 uint32_t target_offset) {
61 AddCompiledMethod(MethodRef(1u), kUnpatchedPcRelativeCode, ArrayRef<const LinkerPatch>(patches));
62 Link();
63
64 auto result = method_offset_map_.FindMethodOffset(MethodRef(1u));
65 ASSERT_TRUE(result.first);
66
67 uint32_t diff = target_offset - (result.second + kAnchorOffset);
68 if (patches[0].GetType() == LinkerPatch::Type::kDexCacheArray) {
69 diff += kDexCacheArrayLwOffset;
70 }
71 diff += (diff & 0x8000) << 1; // Account for sign extension in addiu.
72
73 const uint8_t expected_code[] = {
74 0x00, 0x00, 0x10, 0x04,
75 static_cast<uint8_t>(diff >> 16), static_cast<uint8_t>(diff >> 24), 0x12, 0x3C,
76 0x21, 0x90, 0x5F, 0x02,
77 static_cast<uint8_t>(diff), static_cast<uint8_t>(diff >> 8), 0x52, 0x26,
78 };
79 EXPECT_TRUE(CheckLinkedMethod(MethodRef(1u), ArrayRef<const uint8_t>(expected_code)));
80 }
81
TestDexCacheReference(uint32_t dex_cache_arrays_begin,uint32_t element_offset)82 void MipsRelativePatcherTest::TestDexCacheReference(uint32_t dex_cache_arrays_begin,
83 uint32_t element_offset) {
84 dex_cache_arrays_begin_ = dex_cache_arrays_begin;
85 LinkerPatch patches[] = {
86 LinkerPatch::DexCacheArrayPatch(kLiteralOffset, nullptr, kAnchorOffset, element_offset)
87 };
88 CheckPcRelativePatch(ArrayRef<const LinkerPatch>(patches),
89 dex_cache_arrays_begin_ + element_offset);
90 }
91
TestStringReference(uint32_t string_offset)92 void MipsRelativePatcherTest::TestStringReference(uint32_t string_offset) {
93 constexpr uint32_t kStringIndex = 1u;
94 string_index_to_offset_map_.Put(kStringIndex, string_offset);
95 LinkerPatch patches[] = {
96 LinkerPatch::RelativeStringPatch(kLiteralOffset, nullptr, kAnchorOffset, kStringIndex)
97 };
98 CheckPcRelativePatch(ArrayRef<const LinkerPatch>(patches), string_offset);
99 }
100
TEST_F(MipsRelativePatcherTest,DexCacheReference)101 TEST_F(MipsRelativePatcherTest, DexCacheReference) {
102 TestDexCacheReference(/* dex_cache_arrays_begin */ 0x12345678, /* element_offset */ 0x1234);
103 }
104
TEST_F(MipsRelativePatcherTest,StringReference)105 TEST_F(MipsRelativePatcherTest, StringReference) {
106 TestStringReference(/* string_offset*/ 0x87651234);
107 }
108
109 } // namespace linker
110 } // namespace art
111