llvm-6502/lib/Target/MSP430
Chandler Carruth 426c2bf5cd Revert the majority of the next patch in the address space series:
r165941: Resubmit the changes to llvm core to update the functions to
         support different pointer sizes on a per address space basis.

Despite this commit log, this change primarily changed stuff outside of
VMCore, and those changes do not carry any tests for correctness (or
even plausibility), and we have consistently found questionable or flat
out incorrect cases in these changes. Most of them are probably correct,
but we need to devise a system that makes it more clear when we have
handled the address space concerns correctly, and ideally each pass that
gets updated would receive an accompanying test case that exercises that
pass specificaly w.r.t. alternate address spaces.

However, from this commit, I have retained the new C API entry points.
Those were an orthogonal change that probably should have been split
apart, but they seem entirely good.

In several places the changes were very obvious cleanups with no actual
multiple address space code added; these I have not reverted when
I spotted them.

In a few other places there were merge conflicts due to a cleaner
solution being implemented later, often not using address spaces at all.
In those cases, I've preserved the new code which isn't address space
dependent.

This is part of my ongoing effort to clean out the partial address space
code which carries high risk and low test coverage, and not likely to be
finished before the 3.2 release looms closer. Duncan and I would both
like to see the above issues addressed before we return to these
changes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167222 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-01 09:14:31 +00:00
..
InstPrinter
MCTargetDesc
TargetInfo
CMakeLists.txt
LLVMBuild.txt
Makefile
MSP430.h
MSP430.td
MSP430AsmPrinter.cpp
MSP430BranchSelector.cpp
MSP430CallingConv.td
MSP430FrameLowering.cpp Fix fallout from RegInfo => FrameLowering refactoring on MSP430. 2012-10-17 17:37:11 +00:00
MSP430FrameLowering.h Fix fallout from RegInfo => FrameLowering refactoring on MSP430. 2012-10-17 17:37:11 +00:00
MSP430InstrFormats.td
MSP430InstrInfo.cpp
MSP430InstrInfo.h
MSP430InstrInfo.td
MSP430ISelDAGToDAG.cpp Revert 'Fix a typo 'iff' => 'if''. iff is an abreviation of if and only if. See: http://en.wikipedia.org/wiki/If_and_only_if Commit 164767 2012-09-27 10:14:43 +00:00
MSP430ISelLowering.cpp Revert the majority of the next patch in the address space series: 2012-11-01 09:14:31 +00:00
MSP430ISelLowering.h Move TargetData to DataLayout. 2012-10-08 16:38:25 +00:00
MSP430MachineFunctionInfo.cpp
MSP430MachineFunctionInfo.h
MSP430MCInstLower.cpp
MSP430MCInstLower.h
MSP430RegisterInfo.cpp Fix fallout from RegInfo => FrameLowering refactoring on MSP430. 2012-10-17 17:37:11 +00:00
MSP430RegisterInfo.h Fix fallout from RegInfo => FrameLowering refactoring on MSP430. 2012-10-17 17:37:11 +00:00
MSP430RegisterInfo.td
MSP430SelectionDAGInfo.cpp
MSP430SelectionDAGInfo.h
MSP430Subtarget.cpp
MSP430Subtarget.h
MSP430TargetMachine.cpp Implement a basic VectorTargetTransformInfo interface to be used by the loop and bb vectorizers for modeling the cost of instructions. 2012-10-24 17:22:41 +00:00
MSP430TargetMachine.h Reapply the TargerTransformInfo changes, minus the changes to LSR and Lowerinvoke. 2012-10-18 23:22:48 +00:00
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.