llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-11-01 15:11:24 +00:00

History

Evan Cheng 5a96b3dad2 Add bundle aware API for querying instruction properties and switch the code generator to it. For non-bundle instructions, these behave exactly the same as the MC layer API. For properties like mayLoad / mayStore, look into the bundle and if any of the bundled instructions has the property it would return true. For properties like isPredicable, only return true if all of the bundled instructions have the property. For properties like canFoldAsLoad, isCompare, conservatively return false for bundles. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146026 91177308-0d34-0410-b5e6-96231b3b80d8		2011-12-07 07:15:52 +00:00
..
InstPrinter	build/CMake: Finish removal of add_llvm_library_dependencies.	2011-11-29 19:25:30 +00:00
MCTargetDesc	build/CMake: Finish removal of add_llvm_library_dependencies.	2011-11-29 19:25:30 +00:00
TargetInfo	build/CMake: Finish removal of add_llvm_library_dependencies.	2011-11-29 19:25:30 +00:00
CMakeLists.txt	build/CMake: Finish removal of add_llvm_library_dependencies.	2011-11-29 19:25:30 +00:00
LLVMBuild.txt	LLVMBuild: Add explicit information on whether targets define an assembly printer, assembly parser, or disassembler.	2011-11-11 00:23:56 +00:00
Makefile
MSP430.h
MSP430.td
MSP430AsmPrinter.cpp
MSP430BranchSelector.cpp
MSP430CallingConv.td
MSP430FrameLowering.cpp	Add bundle aware API for querying instruction properties and switch the code	2011-12-07 07:15:52 +00:00
MSP430FrameLowering.h
MSP430InstrFormats.td
MSP430InstrInfo.cpp	Add bundle aware API for querying instruction properties and switch the code	2011-12-07 07:15:52 +00:00
MSP430InstrInfo.h
MSP430InstrInfo.td
MSP430ISelDAGToDAG.cpp
MSP430ISelLowering.cpp	Remove some unnecessary includes of PseudoSourceValue.h.	2011-11-15 07:24:32 +00:00
MSP430ISelLowering.h
MSP430MachineFunctionInfo.h
MSP430MCInstLower.cpp
MSP430MCInstLower.h
MSP430RegisterInfo.cpp
MSP430RegisterInfo.h
MSP430RegisterInfo.td
MSP430SelectionDAGInfo.cpp
MSP430SelectionDAGInfo.h
MSP430Subtarget.cpp
MSP430Subtarget.h
MSP430TargetMachine.cpp	Move global variables in TargetMachine into new TargetOptions class. As an API	2011-12-02 22:16:29 +00:00
MSP430TargetMachine.h	Move global variables in TargetMachine into new TargetOptions class. As an API	2011-12-02 22:16:29 +00:00
README.txt

README.txt

//===---------------------------------------------------------------------===//
// MSP430 backend.
//===---------------------------------------------------------------------===//

DISCLAIMER: Thid backend should be considered as highly experimental. I never
seen nor worked with this MCU, all information was gathered from datasheet
only. The original intention of making this backend was to write documentation
of form "How to write backend for dummies" :) Thes notes hopefully will be
available pretty soon.

Some things are incomplete / not implemented yet (this list surely is not
complete as well):

1. Verify, how stuff is handling implicit zext with 8 bit operands (this might
be modelled currently in improper way - should we need to mark the superreg as
def for every 8 bit instruction?).

2. Libcalls: multiplication, division, remainder. Note, that calling convention
for libcalls is incomptible with calling convention of libcalls of msp430-gcc
(these cannot be used though due to license restriction).

3. Implement multiplication / division by constant (dag combiner hook?).

4. Implement non-constant shifts.

5. Implement varargs stuff.

6. Verify and fix (if needed) how's stuff playing with i32 / i64.

7. Implement floating point stuff (softfp?)

8. Implement instruction encoding for (possible) direct code emission in the
future.

9. Since almost all instructions set flags - implement brcond / select in better
way (currently they emit explicit comparison).

10. Handle imm in comparisons in better way (see comment in MSP430InstrInfo.td)

11. Implement hooks for better memory op folding, etc.