Add tests for Arm64RelativePatcher.

Change-Id: I9d2c21d323137ac143eabb8fdf6ca075bae45c51

3 files changed, 529 insertions, 5 deletions

diff --git a/compiler/linker/arm/relative_patcher_arm_base.h b/compiler/linker/arm/relative_patcher_arm_base.h
index 35a8b8e5f0..78bc941d2d 100644
--- a/compiler/linker/arm/relative_patcher_arm_base.h
+++ b/compiler/linker/arm/relative_patcher_arm_base.h
@@ -56,6 +56,7 @@ class ArmBaseRelativePatcher : public RelativePatcher {
   typedef std::pair<MethodReference, uint32_t> UnprocessedPatch;
   std::deque<UnprocessedPatch> unprocessed_patches_;
 
+  friend class Arm64RelativePatcherTest;
   friend class Thumb2RelativePatcherTest;
 
   DISALLOW_COPY_AND_ASSIGN(ArmBaseRelativePatcher);
diff --git a/compiler/linker/arm64/relative_patcher_arm64_test.cc b/compiler/linker/arm64/relative_patcher_arm64_test.cc
new file mode 100644
index 0000000000..b0399369a6
--- /dev/null
+++ b/compiler/linker/arm64/relative_patcher_arm64_test.cc
@@ -0,0 +1,511 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "linker/relative_patcher_test.h"
+#include "linker/arm64/relative_patcher_arm64.h"
+
+namespace art {
+namespace linker {
+
+class Arm64RelativePatcherTest : public RelativePatcherTest {
+ public:
+  explicit Arm64RelativePatcherTest(const std::string& variant)
+      : RelativePatcherTest(kArm64, variant) { }
+
+ protected:
+  static const uint8_t kCallRawCode[];
+  static const ArrayRef<const uint8_t> kCallCode;
+  static const uint8_t kNopRawCode[];
+  static const ArrayRef<const uint8_t> kNopCode;
+
+  // All branches can be created from kBlPlus0 or kBPlus0 by adding the low 26 bits.
+  static constexpr uint32_t kBlPlus0 = 0x94000000u;
+  static constexpr uint32_t kBPlus0 = 0x14000000u;
+
+  // Special BL values.
+  static constexpr uint32_t kBlPlusMax = 0x95ffffffu;
+  static constexpr uint32_t kBlMinusMax = 0x96000000u;
+
+  // LDUR x2, [sp, #4], i.e. unaligned load crossing 64-bit boundary (assuming aligned sp).
+  static constexpr uint32_t kLdurInsn = 0xf840405fu;
+
+  uint32_t Create2MethodsWithGap(const ArrayRef<const uint8_t>& method1_code,
+                                 const ArrayRef<LinkerPatch>& method1_patches,
+                                 const ArrayRef<const uint8_t>& last_method_code,
+                                 const ArrayRef<LinkerPatch>& last_method_patches,
+                                 uint32_t distance_without_thunks) {
+    CHECK_EQ(distance_without_thunks % kArm64Alignment, 0u);
+    const uint32_t method1_offset =
+        CompiledCode::AlignCode(kTrampolineSize, kArm64) + sizeof(OatQuickMethodHeader);
+    AddCompiledMethod(MethodRef(1u), method1_code, ArrayRef<LinkerPatch>(method1_patches));
+    const uint32_t gap_start =
+        CompiledCode::AlignCode(method1_offset + method1_code.size(), kArm64);
+
+    // We want to put the method3 at a very precise offset.
+    const uint32_t last_method_offset = method1_offset + distance_without_thunks;
+    const uint32_t gap_end = last_method_offset - sizeof(OatQuickMethodHeader);
+    CHECK(IsAligned<kArm64Alignment>(gap_end));
+
+    // Fill the gap with intermediate methods in chunks of 2MiB and the last in [2MiB, 4MiB).
+    // (This allows deduplicating the small chunks to avoid using 256MiB of memory for +-128MiB
+    // offsets by this test.)
+    uint32_t method_idx = 2u;
+    constexpr uint32_t kSmallChunkSize = 2 * MB;
+    std::vector<uint8_t> gap_code;
+    size_t gap_size = gap_end - gap_start;
+    for (; gap_size >= 2u * kSmallChunkSize; gap_size -= kSmallChunkSize) {
+      uint32_t chunk_code_size = kSmallChunkSize - sizeof(OatQuickMethodHeader);
+      gap_code.resize(chunk_code_size, 0u);
+      AddCompiledMethod(MethodRef(method_idx), ArrayRef<const uint8_t>(gap_code),
+                        ArrayRef<LinkerPatch>());
+      method_idx += 1u;
+    }
+    uint32_t chunk_code_size = gap_size - sizeof(OatQuickMethodHeader);
+    gap_code.resize(chunk_code_size, 0u);
+    AddCompiledMethod(MethodRef(method_idx), ArrayRef<const uint8_t>(gap_code),
+                      ArrayRef<LinkerPatch>());
+    method_idx += 1u;
+
+    // Add the last method and link
+    AddCompiledMethod(MethodRef(method_idx), last_method_code, last_method_patches);
+    Link();
+
+    // Check assumptions.
+    CHECK_EQ(GetMethodOffset(1), method1_offset);
+    auto last_result = method_offset_map_.FindMethodOffset(MethodRef(method_idx));
+    CHECK(last_result.first);
+    // There may be a thunk before method2.
+    if (last_result.second != last_method_offset) {
+      // Thunk present. Check that there's only one.
+      uint32_t aligned_thunk_size = CompiledCode::AlignCode(ThunkSize(), kArm64);
+      CHECK_EQ(last_result.second, last_method_offset + aligned_thunk_size);
+    }
+    return method_idx;
+  }
+
+  uint32_t GetMethodOffset(uint32_t method_idx) {
+    auto result = method_offset_map_.FindMethodOffset(MethodRef(method_idx));
+    CHECK(result.first);
+    CHECK_EQ(result.second & 3u, 0u);
+    return result.second;
+  }
+
+  uint32_t ThunkSize() {
+    return static_cast<Arm64RelativePatcher*>(patcher_.get())->thunk_code_.size();
+  }
+
+  bool CheckThunk(uint32_t thunk_offset) {
+    Arm64RelativePatcher* patcher = static_cast<Arm64RelativePatcher*>(patcher_.get());
+    ArrayRef<const uint8_t> expected_code(patcher->thunk_code_);
+    if (output_.size() < thunk_offset + expected_code.size()) {
+      LOG(ERROR) << "output_.size() == " << output_.size() << " < "
+          << "thunk_offset + expected_code.size() == " << (thunk_offset + expected_code.size());
+      return false;
+    }
+    ArrayRef<const uint8_t> linked_code(&output_[thunk_offset], expected_code.size());
+    if (linked_code == expected_code) {
+      return true;
+    }
+    // Log failure info.
+    DumpDiff(expected_code, linked_code);
+    return false;
+  }
+
+  std::vector<uint8_t> GenNopsAndBl(size_t num_nops, uint32_t bl) {
+    std::vector<uint8_t> result;
+    result.reserve(num_nops * 4u + 4u);
+    for (size_t i = 0; i != num_nops; ++i) {
+      result.insert(result.end(), kNopCode.begin(), kNopCode.end());
+    }
+    result.push_back(static_cast<uint8_t>(bl));
+    result.push_back(static_cast<uint8_t>(bl >> 8));
+    result.push_back(static_cast<uint8_t>(bl >> 16));
+    result.push_back(static_cast<uint8_t>(bl >> 24));
+    return result;
+  }
+
+  std::vector<uint8_t> GenNopsAndAdrpLdr(size_t num_nops,
+                                         uint32_t method_offset, uint32_t target_offset) {
+    std::vector<uint8_t> result;
+    result.reserve(num_nops * 4u + 8u);
+    for (size_t i = 0; i != num_nops; ++i) {
+      result.insert(result.end(), kNopCode.begin(), kNopCode.end());
+    }
+    DCHECK_EQ(method_offset & 3u, 0u);
+    DCHECK_EQ(target_offset & 3u, 0u);
+    uint32_t adrp_offset = method_offset + num_nops * 4u;
+    uint32_t disp = target_offset - (adrp_offset & ~0xfffu);
+    DCHECK_EQ(disp & 3u, 0u);
+    uint32_t ldr = 0xb9400001 |               // LDR w1, [x0, #(imm12 * 2)]
+        ((disp & 0xfffu) << (10 - 2));        // imm12 = ((disp & 0xfffu) >> 2) is at bit 10.
+    uint32_t adrp = 0x90000000 |              // ADRP x0, +SignExtend(immhi:immlo:Zeros(12), 64)
+        ((disp & 0x3000u) << (29 - 12)) |     // immlo = ((disp & 0x3000u) >> 12) is at bit 29,
+        ((disp & 0xffffc000) >> (14 - 5)) |   // immhi = (disp >> 14) is at bit 5,
+        // We take the sign bit from the disp, limiting disp to +- 2GiB.
+        ((disp & 0x80000000) >> (31 - 23));   // sign bit in immhi is at bit 23.
+    result.push_back(static_cast<uint8_t>(adrp));
+    result.push_back(static_cast<uint8_t>(adrp >> 8));
+    result.push_back(static_cast<uint8_t>(adrp >> 16));
+    result.push_back(static_cast<uint8_t>(adrp >> 24));
+    result.push_back(static_cast<uint8_t>(ldr));
+    result.push_back(static_cast<uint8_t>(ldr >> 8));
+    result.push_back(static_cast<uint8_t>(ldr >> 16));
+    result.push_back(static_cast<uint8_t>(ldr >> 24));
+    return result;
+  }
+
+  void TestNopsAdrpLdr(size_t num_nops, uint32_t dex_cache_arrays_begin, uint32_t element_offset) {
+    dex_cache_arrays_begin_ = dex_cache_arrays_begin;
+    auto code = GenNopsAndAdrpLdr(num_nops, 0u, 0u);  // Unpatched.
+    LinkerPatch patches[] = {
+        LinkerPatch::DexCacheArrayPatch(num_nops * 4u     , nullptr, num_nops * 4u, element_offset),
+        LinkerPatch::DexCacheArrayPatch(num_nops * 4u + 4u, nullptr, num_nops * 4u, element_offset),
+    };
+    AddCompiledMethod(MethodRef(1u), ArrayRef<const uint8_t>(code), ArrayRef<LinkerPatch>(patches));
+    Link();
+
+    uint32_t method1_offset = GetMethodOffset(1u);
+    uint32_t target_offset = dex_cache_arrays_begin_ + element_offset;
+    auto expected_code = GenNopsAndAdrpLdr(num_nops, method1_offset, target_offset);
+    EXPECT_TRUE(CheckLinkedMethod(MethodRef(1u), ArrayRef<const uint8_t>(expected_code)));
+  }
+
+  void InsertInsn(std::vector<uint8_t>* code, size_t pos, uint32_t insn) {
+    CHECK_LE(pos, code->size());
+    const uint8_t insn_code[] = {
+        static_cast<uint8_t>(insn), static_cast<uint8_t>(insn >> 8),
+        static_cast<uint8_t>(insn >> 16), static_cast<uint8_t>(insn >> 24),
+    };
+    static_assert(sizeof(insn_code) == 4u, "Invalid sizeof(insn_code).");
+    code->insert(code->begin() + pos, insn_code, insn_code + sizeof(insn_code));
+  }
+
+  void PrepareNopsAdrpInsn2Ldr(size_t num_nops, uint32_t insn2,
+                               uint32_t dex_cache_arrays_begin, uint32_t element_offset) {
+    dex_cache_arrays_begin_ = dex_cache_arrays_begin;
+    auto code = GenNopsAndAdrpLdr(num_nops, 0u, 0u);  // Unpatched.
+    InsertInsn(&code, num_nops * 4u + 4u, insn2);
+    LinkerPatch patches[] = {
+        LinkerPatch::DexCacheArrayPatch(num_nops * 4u     , nullptr, num_nops * 4u, element_offset),
+        LinkerPatch::DexCacheArrayPatch(num_nops * 4u + 8u, nullptr, num_nops * 4u, element_offset),
+    };
+    AddCompiledMethod(MethodRef(1u), ArrayRef<const uint8_t>(code), ArrayRef<LinkerPatch>(patches));
+    Link();
+  }
+
+  void TestNopsAdrpInsn2Ldr(size_t num_nops, uint32_t insn2,
+                            uint32_t dex_cache_arrays_begin, uint32_t element_offset) {
+    PrepareNopsAdrpInsn2Ldr(num_nops, insn2, dex_cache_arrays_begin, element_offset);
+
+    uint32_t method1_offset = GetMethodOffset(1u);
+    uint32_t target_offset = dex_cache_arrays_begin_ + element_offset;
+    auto expected_code = GenNopsAndAdrpLdr(num_nops, method1_offset, target_offset);
+    InsertInsn(&expected_code, num_nops * 4u + 4u, insn2);
+    EXPECT_TRUE(CheckLinkedMethod(MethodRef(1u), ArrayRef<const uint8_t>(expected_code)));
+  }
+
+  void TestNopsAdrpInsn2LdrHasThunk(size_t num_nops, uint32_t insn2,
+                                    uint32_t dex_cache_arrays_begin, uint32_t element_offset) {
+    PrepareNopsAdrpInsn2Ldr(num_nops, insn2, dex_cache_arrays_begin, element_offset);
+
+    uint32_t method1_offset = GetMethodOffset(1u);
+    CHECK(!compiled_method_refs_.empty());
+    CHECK_EQ(compiled_method_refs_[0].dex_method_index, 1u);
+    CHECK_EQ(compiled_method_refs_.size(), compiled_methods_.size());
+    uint32_t method1_size = compiled_methods_[0]->GetQuickCode()->size();
+    uint32_t thunk_offset = CompiledCode::AlignCode(method1_offset + method1_size, kArm64);
+    uint32_t b_diff = thunk_offset - (method1_offset + num_nops * 4u);
+    ASSERT_EQ(b_diff & 3u, 0u);
+    ASSERT_LT(b_diff, 128 * MB);
+    uint32_t b_out = kBPlus0 + ((b_diff >> 2) & 0x03ffffffu);
+    uint32_t b_in = kBPlus0 + ((-b_diff >> 2) & 0x03ffffffu);
+
+    uint32_t target_offset = dex_cache_arrays_begin_ + element_offset;
+    auto expected_code = GenNopsAndAdrpLdr(num_nops, method1_offset, target_offset);
+    InsertInsn(&expected_code, num_nops * 4u + 4u, insn2);
+    // Replace adrp with bl.
+    expected_code.erase(expected_code.begin() + num_nops * 4u,
+                        expected_code.begin() + num_nops * 4u + 4u);
+    InsertInsn(&expected_code, num_nops * 4u, b_out);
+    EXPECT_TRUE(CheckLinkedMethod(MethodRef(1u), ArrayRef<const uint8_t>(expected_code)));
+
+    auto expected_thunk_code = GenNopsAndAdrpLdr(0u, thunk_offset, target_offset);
+    ASSERT_EQ(expected_thunk_code.size(), 8u);
+    expected_thunk_code.erase(expected_thunk_code.begin() + 4u, expected_thunk_code.begin() + 8u);
+    InsertInsn(&expected_thunk_code, 4u, b_in);
+    ASSERT_EQ(expected_thunk_code.size(), 8u);
+
+    uint32_t thunk_size = ThunkSize();
+    ASSERT_EQ(thunk_offset + thunk_size, output_.size());
+    ASSERT_EQ(thunk_size, expected_thunk_code.size());
+    ArrayRef<const uint8_t> thunk_code(&output_[thunk_offset], thunk_size);
+    if (ArrayRef<const uint8_t>(expected_thunk_code) != thunk_code) {
+      DumpDiff(ArrayRef<const uint8_t>(expected_thunk_code), thunk_code);
+      FAIL();
+    }
+  }
+
+  void TestAdrpLdurLdr(uint32_t adrp_offset, bool has_thunk,
+                       uint32_t dex_cache_arrays_begin, uint32_t element_offset) {
+    uint32_t method1_offset =
+        CompiledCode::AlignCode(kTrampolineSize, kArm64) + sizeof(OatQuickMethodHeader);
+    ASSERT_LT(method1_offset, adrp_offset);
+    ASSERT_EQ(adrp_offset & 3u, 0u);
+    uint32_t num_nops = (adrp_offset - method1_offset) / 4u;
+    if (has_thunk) {
+      TestNopsAdrpInsn2LdrHasThunk(num_nops, kLdurInsn, dex_cache_arrays_begin, element_offset);
+    } else {
+      TestNopsAdrpInsn2Ldr(num_nops, kLdurInsn, dex_cache_arrays_begin, element_offset);
+    }
+    ASSERT_EQ(method1_offset, GetMethodOffset(1u));  // If this fails, num_nops is wrong.
+  }
+};
+
+const uint8_t Arm64RelativePatcherTest::kCallRawCode[] = {
+    0x00, 0x00, 0x00, 0x94
+};
+
+const ArrayRef<const uint8_t> Arm64RelativePatcherTest::kCallCode(kCallRawCode);
+
+const uint8_t Arm64RelativePatcherTest::kNopRawCode[] = {
+    0x1f, 0x20, 0x03, 0xd5
+};
+
+const ArrayRef<const uint8_t> Arm64RelativePatcherTest::kNopCode(kNopRawCode);
+
+class Arm64RelativePatcherTestDefault : public Arm64RelativePatcherTest {
+ public:
+  Arm64RelativePatcherTestDefault() : Arm64RelativePatcherTest("default") { }
+};
+
+class Arm64RelativePatcherTestDenver64 : public Arm64RelativePatcherTest {
+ public:
+  Arm64RelativePatcherTestDenver64() : Arm64RelativePatcherTest("denver64") { }
+};
+
+TEST_F(Arm64RelativePatcherTestDefault, CallSelf) {
+  LinkerPatch patches[] = {
+      LinkerPatch::RelativeCodePatch(0u, nullptr, 1u),
+  };
+  AddCompiledMethod(MethodRef(1u), kCallCode, ArrayRef<LinkerPatch>(patches));
+  Link();
+
+  static const uint8_t expected_code[] = {
+      0x00, 0x00, 0x00, 0x94
+  };
+  EXPECT_TRUE(CheckLinkedMethod(MethodRef(1u), ArrayRef<const uint8_t>(expected_code)));
+}
+
+TEST_F(Arm64RelativePatcherTestDefault, CallOther) {
+  LinkerPatch method1_patches[] = {
+      LinkerPatch::RelativeCodePatch(0u, nullptr, 2u),
+  };
+  AddCompiledMethod(MethodRef(1u), kCallCode, ArrayRef<LinkerPatch>(method1_patches));
+  LinkerPatch method2_patches[] = {
+      LinkerPatch::RelativeCodePatch(0u, nullptr, 1u),
+  };
+  AddCompiledMethod(MethodRef(2u), kCallCode, ArrayRef<LinkerPatch>(method2_patches));
+  Link();
+
+  uint32_t method1_offset = GetMethodOffset(1u);
+  uint32_t method2_offset = GetMethodOffset(2u);
+  uint32_t diff_after = method2_offset - method1_offset;
+  ASSERT_EQ(diff_after & 3u, 0u);
+  ASSERT_LT(diff_after >> 2, 1u << 8);  // Simple encoding, (diff_after >> 2) fits into 8 bits.
+  static const uint8_t method1_expected_code[] = {
+      static_cast<uint8_t>(diff_after >> 2), 0x00, 0x00, 0x94
+  };
+  EXPECT_TRUE(CheckLinkedMethod(MethodRef(1u), ArrayRef<const uint8_t>(method1_expected_code)));
+  uint32_t diff_before = method1_offset - method2_offset;
+  ASSERT_EQ(diff_before & 3u, 0u);
+  ASSERT_GE(diff_before, -1u << 27);
+  auto method2_expected_code = GenNopsAndBl(0u, kBlPlus0 | ((diff_before >> 2) & 0x03ffffffu));
+  EXPECT_TRUE(CheckLinkedMethod(MethodRef(2u), ArrayRef<const uint8_t>(method2_expected_code)));
+}
+
+TEST_F(Arm64RelativePatcherTestDefault, CallTrampoline) {
+  LinkerPatch patches[] = {
+      LinkerPatch::RelativeCodePatch(0u, nullptr, 2u),
+  };
+  AddCompiledMethod(MethodRef(1u), kCallCode, ArrayRef<LinkerPatch>(patches));
+  Link();
+
+  uint32_t method1_offset = GetMethodOffset(1u);
+  uint32_t diff = kTrampolineOffset - method1_offset;
+  ASSERT_EQ(diff & 1u, 0u);
+  ASSERT_GE(diff, -1u << 9);  // Simple encoding, -256 <= (diff >> 1) < 0 (checked as unsigned).
+  auto expected_code = GenNopsAndBl(0u, kBlPlus0 | ((diff >> 2) & 0x03ffffffu));
+  EXPECT_TRUE(CheckLinkedMethod(MethodRef(1u), ArrayRef<const uint8_t>(expected_code)));
+}
+
+TEST_F(Arm64RelativePatcherTestDefault, CallOtherAlmostTooFarAfter) {
+  auto method1_raw_code = GenNopsAndBl(1u, kBlPlus0);
+  constexpr uint32_t bl_offset_in_method1 = 1u * 4u;  // After NOPs.
+  ArrayRef<const uint8_t> method1_code(method1_raw_code);
+  ASSERT_EQ(bl_offset_in_method1 + 4u, method1_code.size());
+  uint32_t expected_last_method_idx = 65;  // Based on 2MiB chunks in Create2MethodsWithGap().
+  LinkerPatch method1_patches[] = {
+      LinkerPatch::RelativeCodePatch(bl_offset_in_method1, nullptr, expected_last_method_idx),
+  };
+
+  constexpr uint32_t max_positive_disp = 128 * MB - 4u;
+  uint32_t last_method_idx = Create2MethodsWithGap(method1_code, method1_patches,
+                                                   kNopCode, ArrayRef<LinkerPatch>(),
+                                                   bl_offset_in_method1 + max_positive_disp);
+  ASSERT_EQ(expected_last_method_idx, last_method_idx);
+
+  uint32_t method1_offset = GetMethodOffset(1u);
+  uint32_t last_method_offset = GetMethodOffset(last_method_idx);
+  ASSERT_EQ(method1_offset + bl_offset_in_method1 + max_positive_disp, last_method_offset);
+
+  // Check linked code.
+  auto expected_code = GenNopsAndBl(1u, kBlPlusMax);
+  EXPECT_TRUE(CheckLinkedMethod(MethodRef(1u), ArrayRef<const uint8_t>(expected_code)));
+}
+
+TEST_F(Arm64RelativePatcherTestDefault, CallOtherAlmostTooFarBefore) {
+  auto last_method_raw_code = GenNopsAndBl(0u, kBlPlus0);
+  constexpr uint32_t bl_offset_in_last_method = 0u * 4u;  // After NOPs.
+  ArrayRef<const uint8_t> last_method_code(last_method_raw_code);
+  ASSERT_EQ(bl_offset_in_last_method + 4u, last_method_code.size());
+  LinkerPatch last_method_patches[] = {
+      LinkerPatch::RelativeCodePatch(bl_offset_in_last_method, nullptr, 1u),
+  };
+
+  constexpr uint32_t max_negative_disp = 128 * MB;
+  uint32_t last_method_idx = Create2MethodsWithGap(kNopCode, ArrayRef<LinkerPatch>(),
+                                                   last_method_code, last_method_patches,
+                                                   max_negative_disp - bl_offset_in_last_method);
+  uint32_t method1_offset = GetMethodOffset(1u);
+  uint32_t last_method_offset = GetMethodOffset(last_method_idx);
+  ASSERT_EQ(method1_offset, last_method_offset + bl_offset_in_last_method - max_negative_disp);
+
+  // Check linked code.
+  auto expected_code = GenNopsAndBl(0u, kBlMinusMax);
+  EXPECT_TRUE(CheckLinkedMethod(MethodRef(last_method_idx),
+                                ArrayRef<const uint8_t>(expected_code)));
+}
+
+TEST_F(Arm64RelativePatcherTestDefault, CallOtherJustTooFarAfter) {
+  auto method1_raw_code = GenNopsAndBl(0u, kBlPlus0);
+  constexpr uint32_t bl_offset_in_method1 = 0u * 4u;  // After NOPs.
+  ArrayRef<const uint8_t> method1_code(method1_raw_code);
+  ASSERT_EQ(bl_offset_in_method1 + 4u, method1_code.size());
+  uint32_t expected_last_method_idx = 65;  // Based on 2MiB chunks in Create2MethodsWithGap().
+  LinkerPatch method1_patches[] = {
+      LinkerPatch::RelativeCodePatch(bl_offset_in_method1, nullptr, expected_last_method_idx),
+  };
+
+  constexpr uint32_t just_over_max_positive_disp = 128 * MB;
+  uint32_t last_method_idx = Create2MethodsWithGap(
+      method1_code, method1_patches, kNopCode, ArrayRef<LinkerPatch>(),
+      bl_offset_in_method1 + just_over_max_positive_disp);
+  ASSERT_EQ(expected_last_method_idx, last_method_idx);
+
+  uint32_t method1_offset = GetMethodOffset(1u);
+  uint32_t last_method_offset = GetMethodOffset(last_method_idx);
+  uint32_t last_method_header_offset = last_method_offset - sizeof(OatQuickMethodHeader);
+  ASSERT_TRUE(IsAligned<kArm64Alignment>(last_method_header_offset));
+  uint32_t thunk_offset = last_method_header_offset - CompiledCode::AlignCode(ThunkSize(), kArm64);
+  ASSERT_TRUE(IsAligned<kArm64Alignment>(thunk_offset));
+  uint32_t diff = thunk_offset - (method1_offset + bl_offset_in_method1);
+  ASSERT_EQ(diff & 3u, 0u);
+  ASSERT_LT(diff, 128 * MB);
+  auto expected_code = GenNopsAndBl(0u, kBlPlus0 | (diff >> 2));
+  EXPECT_TRUE(CheckLinkedMethod(MethodRef(1u), ArrayRef<const uint8_t>(expected_code)));
+  CheckThunk(thunk_offset);
+}
+
+TEST_F(Arm64RelativePatcherTestDefault, CallOtherJustTooFarBefore) {
+  auto last_method_raw_code = GenNopsAndBl(1u, kBlPlus0);
+  constexpr uint32_t bl_offset_in_last_method = 1u * 4u;  // After NOPs.
+  ArrayRef<const uint8_t> last_method_code(last_method_raw_code);
+  ASSERT_EQ(bl_offset_in_last_method + 4u, last_method_code.size());
+  LinkerPatch last_method_patches[] = {
+      LinkerPatch::RelativeCodePatch(bl_offset_in_last_method, nullptr, 1u),
+  };
+
+  constexpr uint32_t just_over_max_negative_disp = 128 * MB + 4;
+  uint32_t last_method_idx = Create2MethodsWithGap(
+      kNopCode, ArrayRef<LinkerPatch>(), last_method_code, last_method_patches,
+      just_over_max_negative_disp - bl_offset_in_last_method);
+  uint32_t method1_offset = GetMethodOffset(1u);
+  uint32_t last_method_offset = GetMethodOffset(last_method_idx);
+  ASSERT_EQ(method1_offset,
+            last_method_offset + bl_offset_in_last_method - just_over_max_negative_disp);
+
+  // Check linked code.
+  uint32_t thunk_offset =
+      CompiledCode::AlignCode(last_method_offset + last_method_code.size(), kArm64);
+  uint32_t diff = thunk_offset - (last_method_offset + bl_offset_in_last_method);
+  ASSERT_EQ(diff & 3u, 0u);
+  ASSERT_LT(diff, 128 * MB);
+  auto expected_code = GenNopsAndBl(1u, kBlPlus0 | (diff >> 2));
+  EXPECT_TRUE(CheckLinkedMethod(MethodRef(last_method_idx),
+                                ArrayRef<const uint8_t>(expected_code)));
+  EXPECT_TRUE(CheckThunk(thunk_offset));
+}
+
+TEST_F(Arm64RelativePatcherTestDefault, DexCacheReference1) {
+  TestNopsAdrpLdr(0u, 0x12345678u, 0x1234u);
+}
+
+TEST_F(Arm64RelativePatcherTestDefault, DexCacheReference2) {
+  TestNopsAdrpLdr(0u, -0x12345678u, 0x4444u);
+}
+
+TEST_F(Arm64RelativePatcherTestDefault, DexCacheReference3) {
+  TestNopsAdrpLdr(0u, 0x12345000u, 0x3ffcu);
+}
+
+TEST_F(Arm64RelativePatcherTestDefault, DexCacheReference4) {
+  TestNopsAdrpLdr(0u, 0x12345000u, 0x4000u);
+}
+
+TEST_F(Arm64RelativePatcherTestDefault, DexCacheReference0xff4) {
+  TestAdrpLdurLdr(0xff4u, false, 0x12345678u, 0x1234u);
+}
+
+TEST_F(Arm64RelativePatcherTestDefault, DexCacheReference0xff8) {
+  TestAdrpLdurLdr(0xff8u, true, 0x12345678u, 0x1234u);
+}
+
+TEST_F(Arm64RelativePatcherTestDefault, DexCacheReference0xffc) {
+  TestAdrpLdurLdr(0xffcu, true, 0x12345678u, 0x1234u);
+}
+
+TEST_F(Arm64RelativePatcherTestDefault, DexCacheReference0x1000) {
+  TestAdrpLdurLdr(0x1000u, false, 0x12345678u, 0x1234u);
+}
+
+TEST_F(Arm64RelativePatcherTestDenver64, DexCacheReference0xff4) {
+  TestAdrpLdurLdr(0xff4u, false, 0x12345678u, 0x1234u);
+}
+
+TEST_F(Arm64RelativePatcherTestDenver64, DexCacheReference0xff8) {
+  TestAdrpLdurLdr(0xff8u, false, 0x12345678u, 0x1234u);
+}
+
+TEST_F(Arm64RelativePatcherTestDenver64, DexCacheReference0xffc) {
+  TestAdrpLdurLdr(0xffcu, false, 0x12345678u, 0x1234u);
+}
+
+TEST_F(Arm64RelativePatcherTestDenver64, DexCacheReference0x1000) {
+  TestAdrpLdurLdr(0x1000u, false, 0x12345678u, 0x1234u);
+}
+
+}  // namespace linker
+}  // namespace art
diff --git a/compiler/linker/relative_patcher_test.h b/compiler/linker/relative_patcher_test.h
index 9efcf6082b..dede42e71a 100644
--- a/compiler/linker/relative_patcher_test.h
+++ b/compiler/linker/relative_patcher_test.h
@@ -189,17 +189,29 @@ class RelativePatcherTest : public testing::Test {
     for (size_t i = 0; i != expected_code.size(); ++i) {
       expected_hex << " " << digits[expected_code[i] >> 4] << digits[expected_code[i] & 0xf];
       linked_hex << " " << digits[linked_code[i] >> 4] << digits[linked_code[i] & 0xf];
-      diff_indicator << " ";
       if (!found_diff) {
         found_diff = (expected_code[i] != linked_code[i]);
-        diff_indicator << (found_diff ? "^^" : "  ");
+        diff_indicator << (found_diff ? " ^^" : "   ");
       }
     }
     CHECK(found_diff);
+    std::string expected_hex_str = expected_hex.str();
+    std::string linked_hex_str = linked_hex.str();
+    std::string diff_indicator_str = diff_indicator.str();
+    if (diff_indicator_str.length() > 60) {
+      CHECK_EQ(diff_indicator_str.length() % 3u, 0u);
+      size_t remove = diff_indicator_str.length() / 3 - 5;
+      std::ostringstream oss;
+      oss << "[stripped " << remove << "]";
+      std::string replacement = oss.str();
+      expected_hex_str.replace(0u, remove * 3u, replacement);
+      linked_hex_str.replace(0u, remove * 3u, replacement);
+      diff_indicator_str.replace(0u, remove * 3u, replacement);
+    }
     LOG(ERROR) << "diff expected_code linked_code";
-    LOG(ERROR) << "<" << expected_hex.str();
-    LOG(ERROR) << ">" << linked_hex.str();
-    LOG(ERROR) << " " << diff_indicator.str();
+    LOG(ERROR) << "<" << expected_hex_str;
+    LOG(ERROR) << ">" << linked_hex_str;
+    LOG(ERROR) << " " << diff_indicator_str;
   }
 
   // Map method reference to assinged offset.