Make it easier to use DwarfContext with MCJIT

Summary:
This supersedes http://reviews.llvm.org/D4010, hopefully properly
dealing with the JIT case and also adds an actual test case.
DwarfContext was basically already usable for the JIT (and back when
we were overwriting ELF files it actually worked out of the box by
accident), but in order to resolve relocations correctly it needs
to know the load address of the section.
Rather than trying to get this out of the ObjectFile or requiring
the user to create a new ObjectFile just to get some debug info,
this adds the capability to pass in that info directly.
As part of this I separated out part of the LoadedObjectInfo struct
from RuntimeDyld, since it is now required at a higher layer.

Reviewers: lhames, echristo

Reviewed By: echristo

Subscribers: vtjnash, friss, rafael, llvm-commits

Differential Revision: http://reviews.llvm.org/D6961

llvm-svn: 237961

1 files changed, 13 insertions, 0 deletions

diff --git a/llvm/lib/Object/COFFObjectFile.cpp b/llvm/lib/Object/COFFObjectFile.cpp
index 4c38b8fd2b0..d4f3b430614 100644
--- a/llvm/lib/Object/COFFObjectFile.cpp
+++ b/llvm/lib/Object/COFFObjectFile.cpp
@@ -1044,6 +1044,19 @@ symbol_iterator COFFObjectFile::getRelocationSymbol(DataRefImpl Rel) const {
   return symbol_iterator(SymbolRef(Ref, this));
 }
 
+section_iterator COFFObjectFile::getRelocationSection(DataRefImpl Rel) const {
+  symbol_iterator Sym = getRelocationSymbol(Rel);
+  if (Sym == symbol_end())
+    return section_end();
+  COFFSymbolRef Symb = getCOFFSymbol(*Sym);
+  if (!Symb.isSection())
+    return section_end();
+  section_iterator Res(section_end());
+  if (getSymbolSection(Sym->getRawDataRefImpl(),Res))
+    return section_end();
+  return Res;
+}
+
 std::error_code COFFObjectFile::getRelocationType(DataRefImpl Rel,
                                                   uint64_t &Res) const {
   const coff_relocation* R = toRel(Rel);