forked from OSchip/llvm-project
5da3f0512e
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. llvm-svn: 167222 |
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.. | ||
InstPrinter | ||
MCTargetDesc | ||
TargetInfo | ||
CMakeLists.txt | ||
LLVMBuild.txt | ||
MSP430.h | ||
MSP430.td | ||
MSP430AsmPrinter.cpp | ||
MSP430BranchSelector.cpp | ||
MSP430CallingConv.td | ||
MSP430FrameLowering.cpp | ||
MSP430FrameLowering.h | ||
MSP430ISelDAGToDAG.cpp | ||
MSP430ISelLowering.cpp | ||
MSP430ISelLowering.h | ||
MSP430InstrFormats.td | ||
MSP430InstrInfo.cpp | ||
MSP430InstrInfo.h | ||
MSP430InstrInfo.td | ||
MSP430MCInstLower.cpp | ||
MSP430MCInstLower.h | ||
MSP430MachineFunctionInfo.cpp | ||
MSP430MachineFunctionInfo.h | ||
MSP430RegisterInfo.cpp | ||
MSP430RegisterInfo.h | ||
MSP430RegisterInfo.td | ||
MSP430SelectionDAGInfo.cpp | ||
MSP430SelectionDAGInfo.h | ||
MSP430Subtarget.cpp | ||
MSP430Subtarget.h | ||
MSP430TargetMachine.cpp | ||
MSP430TargetMachine.h | ||
Makefile | ||
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.