On some architectures such as Arm and X86 the encoding for a nop may
change depending on the subtarget in operation at the time of
encoding. This change replaces the per module MCSubtargetInfo retained
by the targets AsmBackend in favour of passing through the local
MCSubtargetInfo in operation at the time.
On Arm using the architectural NOP instruction can have a performance
benefit on some implementations.
For Arm I've deleted the copy of the AsmBackend's MCSubtargetInfo to
limit the chances of this causing problems in the future. I've not
done this for other targets such as X86 as there is more frequent use
of the MCSubtargetInfo and it looks to be for stable properties that
we would not expect to vary per function.
This change required threading STI through MCNopsFragment and
MCBoundaryAlignFragment.
I've attempted to take into account the in tree experimental backends.
Differential Revision: https://reviews.llvm.org/D45962
Some files still contained the old University of Illinois Open Source
Licence header. This patch replaces that with the Apache 2 with LLVM
Exception licence.
Differential Revision: https://reviews.llvm.org/D107528
This patch adds basic CSKY branch instructions and symbol address series instructions.
Those two kinds of instruction have relationship between each other, and it involves much work about Fixups.
For now, basic instructions are enabled except for disassembler support.
We would support to generate basic codegen asm firstly and delay disassembler work later.
Differential Revision: https://reviews.llvm.org/D95029
This patch adds basic CSKY integer instructions except for branch series such as bsr, br.
It mainly includes basic ALU, load & store, compare and data move instructions.
Branch series instructions need handle complex symbol operand as following patch later.
Differential Revision: https://reviews.llvm.org/D94007
This basic parser will handle basic instructions with register or immediate operands.
With the addition of CSKYInstPrinter, we can now make use of lit tests.
Differential Revision: https://reviews.llvm.org/D93798
Add basis of CSKY MCTargetDesc and it's enough to compile and link but doesn't yet do anything particularly useful.
Once an ASM parser and printer are added in the next two patches, the whole thing can be usefully tested.
Differential Revision: https://reviews.llvm.org/D93372
This introduce basic tablegen infra such as CSKY{InstrFormats,InstrInfo,RegisterInfo,}.td.
For now, only add instruction definitions for basic CSKY ISA operations, and the instruction format and register info are almost complete.
Our initial target is a working MC layer rather than codegen, so appropriate SelectionDAG patterns will come later.
Differential Revision: https://reviews.llvm.org/D89180
No longer rely on an external tool to build the llvm component layout.
Instead, leverage the existing `add_llvm_componentlibrary` cmake function and
introduce `add_llvm_component_group` to accurately describe component behavior.
These function store extra properties in the created targets. These properties
are processed once all components are defined to resolve library dependencies
and produce the header expected by llvm-config.
Differential Revision: https://reviews.llvm.org/D90848
This patch introduce files that just enough for lib/Target/CSKY to compile.
Notably a basic CSKYTargetMachine and CSKYTargetInfo.
Differential Revision: https://reviews.llvm.org/D88466