Multiple bugfixes, small restructuring.

- Move the load bias stored out of ElfInterface into Elf. For the compressed
  sections, the load bias was not the same as the data from the uncompressed
  section.
- Move the initialization of the compressed section into Init. It was too easy
  to forget to call the init of the compressed section.
- Do not automatically add in load bias to the pc before calling ElfInterface
  code. Do all of the pc manipulations in the Elf object.
- Change the interface GetFunctionName code to pass in the load_bias instead
  of modifying the pc inside the code.
- Modify the Step function to pass in the elf offset, not add it to the pc.
  It is necessary to have two different relative values when executing the
  Step: a pc that is relative to the beginning of the elf for the reading data
  the actual instructions when trying to determine if this is in a signal
  frame, and a pc that is relative to the map for finding the appropriate
  unwind information.
- Add a feature to Unwinder so that an unwind can be stopped if it ends up
  in map that has a specified suffix. This is so that the ART unwinding
  code doesn't require skipping the compressed section. Instead, stop at
  if trying to unwind through a known suffix code that means the code is
  in java code. This is important because the compressed section data is
  not only used by the jave compiled code, so that will continue to work.
- Fix tests for restructuring, add new tests for new functionality.

Test: Ran art test 137-cfi using new unwinder as default.
Test: Ran new unit tests.
Change-Id: I42e658c64c5e14f698ba34944a3043afac967884
diff --git a/libunwindstack/ElfInterface.cpp b/libunwindstack/ElfInterface.cpp
index 46a3f3f..20cc1b0 100644
--- a/libunwindstack/ElfInterface.cpp
+++ b/libunwindstack/ElfInterface.cpp
@@ -118,13 +118,13 @@
 }
 
 template <typename EhdrType, typename PhdrType, typename ShdrType>
-bool ElfInterface::ReadAllHeaders() {
+bool ElfInterface::ReadAllHeaders(uint64_t* load_bias) {
   EhdrType ehdr;
   if (!memory_->Read(0, &ehdr, sizeof(ehdr))) {
     return false;
   }
 
-  if (!ReadProgramHeaders<EhdrType, PhdrType>(ehdr)) {
+  if (!ReadProgramHeaders<EhdrType, PhdrType>(ehdr, load_bias)) {
     return false;
   }
 
@@ -137,7 +137,7 @@
 }
 
 template <typename EhdrType, typename PhdrType>
-bool ElfInterface::ReadProgramHeaders(const EhdrType& ehdr) {
+bool ElfInterface::ReadProgramHeaders(const EhdrType& ehdr, uint64_t* load_bias) {
   uint64_t offset = ehdr.e_phoff;
   for (size_t i = 0; i < ehdr.e_phnum; i++, offset += ehdr.e_phentsize) {
     PhdrType phdr;
@@ -145,7 +145,7 @@
       return false;
     }
 
-    if (HandleType(offset, phdr.p_type)) {
+    if (HandleType(offset, phdr.p_type, *load_bias)) {
       continue;
     }
 
@@ -172,7 +172,7 @@
       pt_loads_[phdr.p_offset] = LoadInfo{phdr.p_offset, phdr.p_vaddr,
                                           static_cast<size_t>(phdr.p_memsz)};
       if (phdr.p_offset == 0) {
-        load_bias_ = phdr.p_vaddr;
+        *load_bias = phdr.p_vaddr;
       }
       break;
     }
@@ -334,14 +334,14 @@
 }
 
 template <typename SymType>
-bool ElfInterface::GetFunctionNameWithTemplate(uint64_t addr, std::string* name,
+bool ElfInterface::GetFunctionNameWithTemplate(uint64_t addr, uint64_t load_bias, std::string* name,
                                                uint64_t* func_offset) {
   if (symbols_.empty()) {
     return false;
   }
 
   for (const auto symbol : symbols_) {
-    if (symbol->GetName<SymType>(addr, load_bias_, memory_, name, func_offset)) {
+    if (symbol->GetName<SymType>(addr, load_bias, memory_, name, func_offset)) {
       return true;
     }
   }
@@ -349,12 +349,6 @@
 }
 
 bool ElfInterface::Step(uint64_t pc, Regs* regs, Memory* process_memory, bool* finished) {
-  // Need to subtract off the load_bias to get the correct pc.
-  if (pc < load_bias_) {
-    return false;
-  }
-  pc -= load_bias_;
-
   // Try the eh_frame first.
   DwarfSection* eh_frame = eh_frame_.get();
   if (eh_frame != nullptr && eh_frame->Step(pc, regs, process_memory, finished)) {
@@ -389,11 +383,11 @@
 template void ElfInterface::InitHeadersWithTemplate<uint32_t>();
 template void ElfInterface::InitHeadersWithTemplate<uint64_t>();
 
-template bool ElfInterface::ReadAllHeaders<Elf32_Ehdr, Elf32_Phdr, Elf32_Shdr>();
-template bool ElfInterface::ReadAllHeaders<Elf64_Ehdr, Elf64_Phdr, Elf64_Shdr>();
+template bool ElfInterface::ReadAllHeaders<Elf32_Ehdr, Elf32_Phdr, Elf32_Shdr>(uint64_t*);
+template bool ElfInterface::ReadAllHeaders<Elf64_Ehdr, Elf64_Phdr, Elf64_Shdr>(uint64_t*);
 
-template bool ElfInterface::ReadProgramHeaders<Elf32_Ehdr, Elf32_Phdr>(const Elf32_Ehdr&);
-template bool ElfInterface::ReadProgramHeaders<Elf64_Ehdr, Elf64_Phdr>(const Elf64_Ehdr&);
+template bool ElfInterface::ReadProgramHeaders<Elf32_Ehdr, Elf32_Phdr>(const Elf32_Ehdr&, uint64_t*);
+template bool ElfInterface::ReadProgramHeaders<Elf64_Ehdr, Elf64_Phdr>(const Elf64_Ehdr&, uint64_t*);
 
 template bool ElfInterface::ReadSectionHeaders<Elf32_Ehdr, Elf32_Shdr>(const Elf32_Ehdr&);
 template bool ElfInterface::ReadSectionHeaders<Elf64_Ehdr, Elf64_Shdr>(const Elf64_Ehdr&);
@@ -401,9 +395,9 @@
 template bool ElfInterface::GetSonameWithTemplate<Elf32_Dyn>(std::string*);
 template bool ElfInterface::GetSonameWithTemplate<Elf64_Dyn>(std::string*);
 
-template bool ElfInterface::GetFunctionNameWithTemplate<Elf32_Sym>(uint64_t, std::string*,
+template bool ElfInterface::GetFunctionNameWithTemplate<Elf32_Sym>(uint64_t, uint64_t, std::string*,
                                                                    uint64_t*);
-template bool ElfInterface::GetFunctionNameWithTemplate<Elf64_Sym>(uint64_t, std::string*,
+template bool ElfInterface::GetFunctionNameWithTemplate<Elf64_Sym>(uint64_t, uint64_t, std::string*,
                                                                    uint64_t*);
 
 template void ElfInterface::GetMaxSizeWithTemplate<Elf32_Ehdr>(Memory*, uint64_t*);