[PATCH] Make it easier to use DwarfContext with MCJIT and add RelocVisitor support for Darwin

[Rafael Ávila de Espíndola]

REPOSITORY
  rL LLVM

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Comment at: include/llvm/Object/ELFObjectFile.h:569
@@ -567,1 +568,3 @@
 
+// ELF relocations can not target sections
+template <class ELFT>
----------------
Not directly, but  It is valid to write

.long .text

and it is represented as a relocation to a symbol, and the symbol has type STT_SECTION.

Would it be desirable to check for that here? If not, please expand the comment a bit.

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Comment at: include/llvm/Object/MachO.h:249
@@ -247,2 +248,3 @@
                                       bool &Result) const override;
+  std::error_code getRelocationLength(DataRefImpl Rel, uint8_t &Res) const;
 
----------------
Please return an ErrorOr<uint8_t>.

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Comment at: include/llvm/Object/RelocVisitor.h:278
@@ +277,3 @@
+    uint8_t Length;
+    Obj->getRelocationLength(DRI, Length);
+    return Length;
----------------
As you can see it is way too easy to ignore a std::error_code return :-)

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Comment at: lib/Object/COFFObjectFile.cpp:1040
@@ -1039,1 +1039,3 @@
 
+section_iterator COFFObjectFile::getRelocationSection(DataRefImpl Rel) const {
+  return section_end();
----------------
Someone familiar with COFF should check this.

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Comment at: lib/Object/MachOObjectFile.cpp:1010
@@ +1009,3 @@
+  Res = getAnyRelocationLength(RE);
+  return object_error::success;
+}
----------------
Actually, if this is never going to fail, just return a uint8_t.

http://reviews.llvm.org/D6961

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