forked from OSchip/llvm-project
5e693ed07b
it is highly specific to the object file that will be generated in the end, this introduces a new TargetLoweringObjectFile interface that is implemented for each of ELF/MachO/COFF/Alpha/PIC16 and XCore. Though still is still a brutal and ugly refactoring, this is a major step towards goodness. This patch also: 1. fixes a bunch of dangling pointer problems in the PIC16 backend. 2. disables the TargetLowering copy ctor which PIC16 was accidentally using. 3. gets us closer to xcore having its own crazy target section flags and pic16 not having to shadow sections with its own objects. 4. fixes wierdness where ELF targets would set CStringSection but not CStringSection_. Factor the code better. 5. fixes some bugs in string lowering on ELF targets. llvm-svn: 77294 |
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.. | ||
TargetInfo | ||
CMakeLists.txt | ||
MSP430.h | ||
MSP430.td | ||
MSP430AsmPrinter.cpp | ||
MSP430CallingConv.td | ||
MSP430ISelDAGToDAG.cpp | ||
MSP430ISelLowering.cpp | ||
MSP430ISelLowering.h | ||
MSP430InstrFormats.td | ||
MSP430InstrInfo.cpp | ||
MSP430InstrInfo.h | ||
MSP430InstrInfo.td | ||
MSP430MachineFunctionInfo.h | ||
MSP430RegisterInfo.cpp | ||
MSP430RegisterInfo.h | ||
MSP430RegisterInfo.td | ||
MSP430Subtarget.cpp | ||
MSP430Subtarget.h | ||
MSP430TargetAsmInfo.cpp | ||
MSP430TargetAsmInfo.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): 0. Implement asmprinting for variables :) 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.