In the Atom model the symbols, content and relocations of a relocatable object
file are represented as a graph of atoms, where each Atom represents a
contiguous block of content with a single name (or no name at all if the
content is anonymous), and where edges between Atoms represent relocations.
If more than one symbol is associated with a contiguous block of content then
the content is broken into multiple atoms and layout constraints (represented by
edges) are introduced to ensure that the content remains effectively contiguous.
These layout constraints must be kept in mind when examining the content
associated with a symbol (it may be spread over multiple atoms) or when applying
certain relocation types (e.g. MachO subtractors).
This patch replaces the Atom model in JITLink with a blocks-and-symbols model.
The blocks-and-symbols model represents relocatable object files as bipartite
graphs, with one set of nodes representing contiguous content (Blocks) and
another representing named or anonymous locations (Symbols) within a Block.
Relocations are represented as edges from Blocks to Symbols. This scheme
removes layout constraints (simplifying handling of MachO alt-entry symbols,
and hopefully ELF sections at some point in the future) and simplifies some
relocation logic.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@373689 91177308-0d34-0410-b5e6-96231b3b80d8
On MachO, processing of the eh-frame section should stop if the end of the
__eh_frame section is reached, regardless of whether or not there is a null CFI
length field at the end of the section. This patch tracks the eh-frame section
size and threads it through the appropriate APIs so that processing can be
terminated correctly.
No testcase yet: This patch is all API plumbing (rather than modification of
linked memory) which the existing infrastructure does not provide a way of
testing. Committing without a testcase until I have an idea of how to write
one.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@370074 91177308-0d34-0410-b5e6-96231b3b80d8
Replaces direct calls to eh-frame registration with calls to methods on an
EHFrameRegistrar instance. This allows clients to substitute a registrar that
registers frames in a remote process via IPC/RPC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@365098 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
EH Frames aren't supported on AIX with the system compiler, but the definition of HAVE_EHTABLE_SUPPORT misses this which causes linking problems on AIX. This patch updates the definition of HAVE_EHTABLE_SUPPORT in both JITLink and RuntimeDyld.
Author: daltenty
Reviewers: sfertile, xingxue, hubert.reinterpretcase
Reviewed By: xingxue
Subscribers: hiraditya, jsji, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62203
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@361410 91177308-0d34-0410-b5e6-96231b3b80d8
These operations were already used in eh-frame registration, and are likely to
be used in other runtime registrations, so this commit moves them into a header
where they can be re-used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@359950 91177308-0d34-0410-b5e6-96231b3b80d8
ObjectLinkingLayer::Plugin provides event notifications when objects are loaded,
emitted, and removed. It also provides a modifyPassConfig callback that allows
plugins to modify the JITLink pass configuration.
This patch moves eh-frame registration into its own plugin, and teaches
llvm-jitlink to only add that plugin when performing execution runs on
non-Windows platforms. This should allow us to re-enable the test case that was
removed in r359198.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@359357 91177308-0d34-0410-b5e6-96231b3b80d8
Frame Descriptor Entries (FDEs) have a pointer back to a Common Information
Entry (CIE) that describes how the rest FDE should be parsed. JITLink had been
assuming that FDEs always referred to the most recent CIE encountered, but the
spec allows them to point back to any previously encountered CIE. This patch
fixes JITLink to look up the correct CIE for the FDE.
The testcase is a MachO binary with an FDE that refers to a CIE that is not the
one immediately proceeding it (the layout can be viewed wit
'dwarfdump --eh-frame <testcase>'. This test case had to be a binary as llvm-mc
now sorts FDEs (as of r356216) to ensure FDEs *do* point to the most recent CIE.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@359105 91177308-0d34-0410-b5e6-96231b3b80d8
