This is dead code since PIC16 was removed in 2010. The result was an odd mix,
where some parts would carefully pass it along and others would assert it was
zero (most of the object streamer for example).
llvm-svn: 185436
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annotation will be superseded by more related functionality.
llvm-svn: 182628
It was just a less powerful and more confusing version of
MCCFIInstruction. A side effect is that, since MCCFIInstruction uses
dwarf register numbers, calls to getDwarfRegNum are pushed out, which
should allow further simplifications.
I left the MachineModuleInfo::addFrameMove interface unchanged since
this patch was already fairly big.
llvm-svn: 181680
R_AARCH64_PCREL32 is present in even trivial .eh_frame sections and so
is required to compile any function without the "nounwind" attribute.
This change implements very basic infrastructure in the RuntimeDyldELF
file and allows (for example) the test-shift.ll MCJIT test to pass
on AArch64.
llvm-svn: 181131
The MOVZ/MOVK instruction sequence may not be the most efficient (a
literal-pool load could be better) but adding that would require
reinstating the ConstantIslands pass.
For now the sequence is correct, and that's enough. Beware, as of
commit GNU ld does not appear to support the relocations needed for
this. Its primary purpose (for now) will be to support JITed code,
since in that case there is no guarantee of where your code will end
up in memory relative to external symbols it references.
llvm-svn: 181117
The work done by the post-encoder (setting architecturally unused bits to 0 as
required) can be done by the existing operand that covers the "#0.0". This
removes at least one use of the discouraged PostEncoderMethod uses.
llvm-svn: 176261
fields were only ever set in the constructor. The create method retains
its consistent interface so that these bits can be re-threaded through
the emitter if they're ever needed.
This was found by the -Wunused-private-field Clang warning.
llvm-svn: 175482
This moves the bit twiddling and string fiddling functions required by other
parts of the backend into a separate library. Previously they resided in
AArch64Desc, which created a circular dependency between various components.
llvm-svn: 174369
This patch adds support for AArch64 (ARM's 64-bit architecture) to
LLVM in the "experimental" category. Currently, it won't be built
unless requested explicitly.
This initial commit should have support for:
+ Assembly of all scalar (i.e. non-NEON, non-Crypto) instructions
(except the late addition CRC instructions).
+ CodeGen features required for C++03 and C99.
+ Compilation for the "small" memory model: code+static data <
4GB.
+ Absolute and position-independent code.
+ GNU-style (i.e. "__thread") TLS.
+ Debugging information.
The principal omission, currently, is performance tuning.
This patch excludes the NEON support also reviewed due to an outbreak of
batshit insanity in our legal department. That will be committed soon bringing
the changes to precisely what has been approved.
Further reviews would be gratefully received.
llvm-svn: 174054