llvm-6502/lib/Target/MSP430
Hal Finkel 3080d23fde Provide the register scavenger to processFunctionBeforeFrameFinalized
Add the current PEI register scavenger as a parameter to the
processFunctionBeforeFrameFinalized callback.

This change is necessary in order to allow the PowerPC target code to
set the register scavenger frame index after the save-area offset
adjustments performed by processFunctionBeforeFrameFinalized. Only
after these adjustments have been made is it possible to estimate
the size of the stack frame.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177108 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-14 20:33:40 +00:00
..
InstPrinter
MCTargetDesc
TargetInfo
CMakeLists.txt
LLVMBuild.txt
Makefile
MSP430.h
MSP430.td
MSP430AsmPrinter.cpp
MSP430BranchSelector.cpp
MSP430CallingConv.td
MSP430FrameLowering.cpp Provide the register scavenger to processFunctionBeforeFrameFinalized 2013-03-14 20:33:40 +00:00
MSP430FrameLowering.h Provide the register scavenger to processFunctionBeforeFrameFinalized 2013-03-14 20:33:40 +00:00
MSP430InstrFormats.td
MSP430InstrInfo.cpp
MSP430InstrInfo.h
MSP430InstrInfo.td Move MRI liveouts to MSP430 return instructions. 2013-02-05 18:12:06 +00:00
MSP430ISelDAGToDAG.cpp
MSP430ISelLowering.cpp Move MRI liveouts to MSP430 return instructions. 2013-02-05 18:12:06 +00:00
MSP430ISelLowering.h Fix PR10475 2013-03-01 18:40:30 +00:00
MSP430MachineFunctionInfo.cpp
MSP430MachineFunctionInfo.h
MSP430MCInstLower.cpp
MSP430MCInstLower.h
MSP430RegisterInfo.cpp Move the eliminateCallFramePseudoInstr method from TargetRegisterInfo 2013-02-21 20:05:00 +00:00
MSP430RegisterInfo.h Move the eliminateCallFramePseudoInstr method from TargetRegisterInfo 2013-02-21 20:05:00 +00:00
MSP430RegisterInfo.td
MSP430SelectionDAGInfo.cpp
MSP430SelectionDAGInfo.h
MSP430Subtarget.cpp
MSP430Subtarget.h
MSP430TargetMachine.cpp
MSP430TargetMachine.h
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.