From 623f2025a7a32de68a5ab402aa2b50ca3e3a6958 Mon Sep 17 00:00:00 2001
From: Lang Hames <lhames@gmail.com>
Date: Fri, 9 Aug 2013 00:57:01 +0000
Subject: [PATCH] Optimistically ignore scattered relocations in MachO in
 RuntimeDyld. This un-breaks simple use cases while I work on more general
 support.

<rdar://problem/14487667>



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188044 91177308-0d34-0410-b5e6-96231b3b80d8
---
 .../RuntimeDyld/RuntimeDyldMachO.cpp              |  10 ++++++++++
 .../RuntimeDyld/Inputs/arm_secdiff_reloc.o        | Bin 0 -> 616 bytes
 .../RuntimeDyld/arm_secdiff_reloc.test            |   1 +
 test/ExecutionEngine/RuntimeDyld/lit.local.cfg    |   1 +
 4 files changed, 12 insertions(+)
 create mode 100644 test/ExecutionEngine/RuntimeDyld/Inputs/arm_secdiff_reloc.o
 create mode 100644 test/ExecutionEngine/RuntimeDyld/arm_secdiff_reloc.test
 create mode 100644 test/ExecutionEngine/RuntimeDyld/lit.local.cfg

diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
index 0384b322624..5d5ff3a2c41 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
@@ -287,6 +287,16 @@ void RuntimeDyldMachO::processRelocationRef(unsigned SectionID,
   macho::RelocationEntry RE = MachO->getRelocation(RelI.getRawDataRefImpl());
 
   uint32_t RelType = MachO->getAnyRelocationType(RE);
+
+  // FIXME: Properly handle scattered relocations.
+  //        For now, optimistically skip these: they can often be ignored, as
+  //        the static linker will already have applied the relocation, and it
+  //        only needs to be reapplied if symbols move relative to one another.
+  //        Note: This will fail horribly where the relocations *do* need to be
+  //        applied, but that was already the case.
+  if (MachO->isRelocationScattered(RE))
+    return;
+
   RelocationValueRef Value;
   SectionEntry &Section = Sections[SectionID];
 
diff --git a/test/ExecutionEngine/RuntimeDyld/Inputs/arm_secdiff_reloc.o b/test/ExecutionEngine/RuntimeDyld/Inputs/arm_secdiff_reloc.o
new file mode 100644
index 0000000000000000000000000000000000000000..5392266cf560cb739b8ef0d2d15932f92bf73f2f
GIT binary patch
literal 616
zcmX^2>+L@t1_lOhAZ7$&W+46oVkkiPJs>s~AOaK<U}9hZ(d<yn3RM>$Uy@o;0_6ay
z`1lalh!6xH#DeJu8o{6fBv?R#EDQ}G3Irf#B<CmQ#OHyGLN^1X9|S;pkpa*j4KRLu
zd~$wXaS4!2%mIm!U<S+xpq_%v<l@TQr2L%XlF}p-V$I-ynjiqSH@GCRBs1AFFB9Yy
zqTK;h+5l1y0w8Zn0I>^@0b<7h30S-Z0QtxOBoD%5g2xOD4nW-hK<>Z(Ll6eW%}kI#
lfM6ojU!72XBZv=5BJ$950!jlQHdsDB&5$8J%?K#O003e`IAj0-

literal 0
HcmV?d00001

diff --git a/test/ExecutionEngine/RuntimeDyld/arm_secdiff_reloc.test b/test/ExecutionEngine/RuntimeDyld/arm_secdiff_reloc.test
new file mode 100644
index 00000000000..92e4dd793cc
--- /dev/null
+++ b/test/ExecutionEngine/RuntimeDyld/arm_secdiff_reloc.test
@@ -0,0 +1 @@
+RUN: llvm-rtdyld -printline %p/Inputs/arm_secdiff_reloc.o
diff --git a/test/ExecutionEngine/RuntimeDyld/lit.local.cfg b/test/ExecutionEngine/RuntimeDyld/lit.local.cfg
new file mode 100644
index 00000000000..df9b335dd13
--- /dev/null
+++ b/test/ExecutionEngine/RuntimeDyld/lit.local.cfg
@@ -0,0 +1 @@
+config.suffixes = ['.test']
-- 
2.34.1