6 Commits

Author SHA1 Message Date
Ahmed Bougacha
f176482752 MC CFG: Support disassembly at arbitrary addresses in MCObjectDisassembler.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188889 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-21 07:28:55 +00:00
Ahmed Bougacha
0f4a5ba24e MC CFG: Add an MCObjectSymbolizer in the MCObjectDisassembler.
Used to detect calls to function symbol stubs (future commit).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188887 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-21 07:28:48 +00:00
Ahmed Bougacha
0e83b90283 MC CFG: Add MCObjectDisassembler Mach-O implementation.
Supports:
- entrypoint, using LC_MAIN.
- static ctors/dtors, using __mod_{init,exit}_func
- translation between effective and object load address, using
  dyld's VM address slide.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188886 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-21 07:28:44 +00:00
Ahmed Bougacha
484a6eb9cc MC CFG: Add "dynamic disassembly" support to MCObjectDisassembler.
It can now disassemble code in situations where the effective load
address is different than the load address declared in the object file.
This happens for PIC, hence "dynamic".

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188884 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-21 07:28:37 +00:00
Ahmed Bougacha
0a30cccd49 MC CFG: Add MCObjectDisassembler support for entrypoint + static ctors.
For now, this isn't implemented for any format.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188882 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-21 07:28:29 +00:00
Ahmed Bougacha
ef99356dfe MC: Disassembled CFG reconstruction.
This patch builds on some existing code to do CFG reconstruction from
a disassembled binary:
- MCModule represents the binary, and has a list of MCAtoms.
- MCAtom represents either disassembled instructions (MCTextAtom), or
  contiguous data (MCDataAtom), and covers a specific range of addresses.
- MCBasicBlock and MCFunction form the reconstructed CFG. An MCBB is
  backed by an MCTextAtom, and has the usual successors/predecessors.
- MCObjectDisassembler creates a module from an ObjectFile using a
  disassembler. It first builds an atom for each section. It can also
  construct the CFG, and this splits the text atoms into basic blocks.

MCModule and MCAtom were only sketched out; MCFunction and MCBB were
implemented under the experimental "-cfg" llvm-objdump -macho option.
This cleans them up for further use; llvm-objdump -d -cfg now generates
graphviz files for each function found in the binary.

In the future, MCObjectDisassembler may be the right place to do
"intelligent" disassembly: for example, handling constant islands is just
a matter of splitting the atom, using information that may be available
in the ObjectFile. Also, better initial atom formation than just using
sections is possible using symbols (and things like Mach-O's
function_starts load command).

This brings two minor regressions in llvm-objdump -macho -cfg:
- The printing of a relocation's referenced symbol.
- An annotation on loop BBs, i.e., which are their own successor.

Relocation printing is replaced by the MCSymbolizer; the basic CFG
annotation will be superseded by more related functionality.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182628 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-24 01:07:04 +00:00