Add a relocation to ObjectFileELF::ApplyRelocations and a test

Summary:
pcm files can end up being processed by lldb with relocations to be
made for the .debug_info section. When a R_AARCH64_ABS64 relocation
was required lldb would hit an `assert(false)` and die.

Add R_AARCH64_ABS64 relocations to the S+A 64 bit width code path. Add
a test for R_AARCH64_ABS64 and R_AARCH64_ABS32 .rela.debug_info
relocations in a pcm file.

Reviewers: sas, xiaobai, davide, javed.absar, espindola

Reviewed By: davide

Subscribers: labath, zturner, emaste, mgorny, arichardson, kristof.beyls

Differential Revision: https://reviews.llvm.org/D51566

llvm-svn: 346171

1 files changed, 62 insertions, 0 deletions

diff --git a/lldb/unittests/ObjectFile/ELF/TestObjectFileELF.cpp b/lldb/unittests/ObjectFile/ELF/TestObjectFileELF.cpp
index a28c49f5513..86bbe0330b7 100644
--- a/lldb/unittests/ObjectFile/ELF/TestObjectFileELF.cpp
+++ b/lldb/unittests/ObjectFile/ELF/TestObjectFileELF.cpp
@@ -16,6 +16,7 @@
 #include "lldb/Core/Section.h"
 #include "lldb/Host/FileSystem.h"
 #include "lldb/Host/HostInfo.h"
+#include "lldb/Utility/DataBufferHeap.h"
 #include "llvm/ADT/Optional.h"
 #include "llvm/Support/Compression.h"
 #include "llvm/Support/FileUtilities.h"
@@ -141,3 +142,64 @@ TEST_F(ObjectFileELFTest, GetModuleSpecifications_EarlySectionHeaders) {
   Uuid.SetFromStringRef("1b8a73ac238390e32a7ff4ac8ebe4d6a41ecf5c9", 20);
   EXPECT_EQ(Spec.GetUUID(), Uuid);
 }
+
+#define CHECK_ABS32(offset, addend)                                            \
+  ASSERT_EQ((uint32_t)addend, *(uint32_t *)(bytes + offset))
+#define CHECK_ABS64(offset, addend)                                            \
+  ASSERT_EQ((uint64_t)addend, *(uint64_t *)(bytes + offset))
+
+TEST_F(ObjectFileELFTest, TestAARCH64Relocations) {
+  std::string yaml = GetInputFilePath("debug-info-relocations.pcm.yaml");
+  llvm::SmallString<128> obj;
+  ASSERT_NO_ERROR(llvm::sys::fs::createTemporaryFile(
+      "debug-info-relocations-%%%%%%", "obj", obj));
+
+  llvm::FileRemover remover(obj);
+  llvm::StringRef args[] = {YAML2OBJ, yaml};
+  llvm::StringRef obj_ref = obj;
+  const llvm::Optional<llvm::StringRef> redirects[] = {llvm::None, obj_ref,
+                                                       llvm::None};
+  ASSERT_EQ(0,
+            llvm::sys::ExecuteAndWait(YAML2OBJ, args, llvm::None, redirects));
+  uint64_t size;
+  ASSERT_NO_ERROR(llvm::sys::fs::file_size(obj, size));
+  ASSERT_GT(size, 0u);
+
+  ModuleSpec spec{FileSpec(obj)};
+  spec.GetSymbolFileSpec().SetFile(obj, FileSpec::Style::native);
+  auto module_sp = std::make_shared<Module>(spec);
+
+  auto objfile = static_cast<ObjectFileELF *>(module_sp->GetObjectFile());
+  SectionList *section_list = objfile->GetSectionList();
+  ASSERT_NE(nullptr, section_list);
+
+  auto debug_info_sp =
+      section_list->FindSectionByName(ConstString(".debug_info"));
+  ASSERT_NE(nullptr, debug_info_sp);
+  objfile->RelocateSection(debug_info_sp.get());
+
+  DataExtractor data;
+  // length of 0x10 is not needed but length 0x0 crashes
+  objfile->GetData(0x00, 0x10, data);
+  DataBufferSP &data_buffer_sp = data.GetSharedDataBuffer();
+  uint8_t *bytes = data_buffer_sp->GetBytes();
+
+  addr_t debug_info_offset = debug_info_sp->GetFileOffset();
+  bytes += debug_info_offset;
+
+  // Sanity check - The first byte from the yaml file is 0x47
+  ASSERT_EQ(0x47, *bytes);
+
+  // .rela.debug_info contains 9 relocations:
+  // 7 R_AARCH64_ABS32 - 2 R_AARCH64_ABS64
+  // None have a value. Four have addends.
+  CHECK_ABS32(0x6, 0);
+  CHECK_ABS32(0xC, 0);
+  CHECK_ABS32(0x12, 45);
+  CHECK_ABS32(0x16, 0);
+  CHECK_ABS32(0x1A, 55);
+  CHECK_ABS64(0x1E, 0);
+  CHECK_ABS64(0x2B, 0);
+  CHECK_ABS32(0x39, 73);
+  CHECK_ABS32(0x44, 75);
+}