[DebugInfo] Basic .debug_names dumping support

Summary:
This commit renames DWARFAcceleratorTable to AppleAcceleratorTable to free up
the first name as an interface for the different accelerator tables.
Then I add a DWARFDebugNames class for the dwarf5 table.

Presently, the only common functionality of the two classes is the dump()
method, because this is the only method that was necessary to implement
dwarfdump -debug-names; and because the rest of the
AppleAcceleratorTable interface does not directly transfer to the dwarf5
tables (the main reason for that is that the present interface assumes
the tables are homogeneous, but the dwarf5 tables can have different
keys associated with each entry).

I expect to make the common interface richer as I add more functionality
to the new class (and invent a way to represent it in generic way).

In terms of sharing the implementation, I found the format of the two
tables sufficiently different to frustrate any attempts to have common
parsing or dumping code, so presently the implementations share just low
level code for formatting dwarf constants.

Reviewers: vleschuk, JDevlieghere, clayborg, aprantl, probinson, echristo, dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42297

llvm-svn: 323638

1 files changed, 1 insertions, 0 deletions

diff --git a/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp b/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
index 1142fe3319c..21493774dc9 100644
--- a/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
+++ b/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
@@ -377,6 +377,7 @@ static bool dumpObjectFile(ObjectFile &Obj, DWARFContext &DICtx, Twine Filename,
           return DumpOffsets[DIDT_ID_DebugInfo] = *Offset;
         if (auto Offset = find(DICtx.getAppleNamespaces()))
           return DumpOffsets[DIDT_ID_DebugInfo] = *Offset;
+        // TODO: Add .debug_names support
       }
       return None;
     }();