[lld] r222200 - [mach-o] enhance arm64 reloc parser to support local pointer relocations

[Nick Kledzik]

Author: kledzik
Date: Mon Nov 17 18:30:22 2014
New Revision: 222200

URL: http://llvm.org/viewvc/llvm-project?rev=222200&view=rev
Log:
[mach-o] enhance arm64 reloc parser to support local pointer relocations

The arm64 assembler almost always uses r_extern=1 relocations in which the
r_symbolnum field is the index of the symbol the relocation references.  But
sometimes it will set r_extern=0 in which case the linker needs to read the
content of the reloction to determine the target.

Add test case that the r_extern=0 relocation round trips.

Modified:
    lld/trunk/lib/ReaderWriter/MachO/ArchHandler_arm64.cpp

Modified: lld/trunk/lib/ReaderWriter/MachO/ArchHandler_arm64.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/lib/ReaderWriter/MachO/ArchHandler_arm64.cpp?rev=222200&r1=222199&r2=222200&view=diff
==============================================================================
--- lld/trunk/lib/ReaderWriter/MachO/ArchHandler_arm64.cpp (original)
+++ lld/trunk/lib/ReaderWriter/MachO/ArchHandler_arm64.cpp Mon Nov 17 18:30:22 2014
@@ -717,7 +717,11 @@ void ArchHandler_arm64::appendSectionRel
                   ARM64_RELOC_TLVP_LOAD_PAGEOFF12 | rExtern | rLength4);
     return;
   case pointer64:
-    appendReloc(relocs, sectionOffset, symbolIndexForAtom(*ref.target()), 0,
+    if (ref.target()->name().empty())
+      appendReloc(relocs, sectionOffset, sectionIndexForAtom(*ref.target()), 0,
+                  ARM64_RELOC_UNSIGNED           | rLength8);
+    else
+      appendReloc(relocs, sectionOffset, symbolIndexForAtom(*ref.target()), 0,
                   ARM64_RELOC_UNSIGNED | rExtern | rLength8);
     return;
   case delta64: