Add debug info for link-time generated thunks.

Add debug info for method call thunks (currently unused) and
Baker read barrier thunks. Refactor debug info generation
for trampolines and record their sizes; change their names
to start with upper-case letters, so that they can be easily
generated as `#fn_name`.

This improved debug info must be generated by `dex2oat -g`,
the debug info generated by `oatdump --symbolize` remains
the same as before, except for the renamed trampolines and
an adjustment for "code delta", i.e. the Thumb mode bit.

Cortex-A53 erratum 843419 workaround thunks are not covered
by this CL.

Test: Manual; run-test --gdb -Xcompiler-option -g 160, pull
      symbols for gdbclient, break in the introspection
      entrypoint, check that gdb knows the new symbols
      (and disassembles them) and `backtrace` works when
      setting $pc to an address in the thunk.
Bug: 36141117
Change-Id: Id224b72cfa7a0628799c7db65e66e24c8517aabf

1 files changed, 2 insertions, 2 deletions

diff --git a/compiler/optimizing/optimizing_compiler.cc b/compiler/optimizing/optimizing_compiler.cc
index 399cd98983..73b0fa2bfa 100644
--- a/compiler/optimizing/optimizing_compiler.cc
+++ b/compiler/optimizing/optimizing_compiler.cc
@@ -1269,8 +1269,8 @@ bool OptimizingCompiler::JitCompile(Thread* self,
   if (compiler_options.GetGenerateDebugInfo()) {
     const auto* method_header = reinterpret_cast<const OatQuickMethodHeader*>(code);
     const uintptr_t code_address = reinterpret_cast<uintptr_t>(method_header->GetCode());
-    debug::MethodDebugInfo info = debug::MethodDebugInfo();
-    info.trampoline_name = nullptr;
+    debug::MethodDebugInfo info = {};
+    DCHECK(info.trampoline_name.empty());
     info.dex_file = dex_file;
     info.class_def_index = class_def_idx;
     info.dex_method_index = method_idx;