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The old system was fairly convoluted: * A temporary label was created. * A single PROLOG_LABEL was created with it. * A few MCCFIInstructions were created with the same label. The semantics were that the cfi instructions were mapped to the PROLOG_LABEL via the temporary label. The output position was that of the PROLOG_LABEL. The temporary label itself was used only for doing the mapping. The new CFI_INSTRUCTION has a 1:1 mapping to MCCFIInstructions and points to one by holding an index into the CFI instructions of this function. I did consider removing MMI.getFrameInstructions completelly and having CFI_INSTRUCTION own a MCCFIInstruction, but MCCFIInstructions have non trivial constructors and destructors and are somewhat big, so the this setup is probably better. The net result is that we don't create temporary labels that are never used. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203204 91177308-0d34-0410-b5e6-96231b3b80d8 |
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.. | ||
InstPrinter | ||
MCTargetDesc | ||
TargetInfo | ||
CMakeLists.txt | ||
LLVMBuild.txt | ||
Makefile | ||
MSP430.h | ||
MSP430.td | ||
MSP430AsmPrinter.cpp | ||
MSP430BranchSelector.cpp | ||
MSP430CallingConv.td | ||
MSP430FrameLowering.cpp | ||
MSP430FrameLowering.h | ||
MSP430InstrFormats.td | ||
MSP430InstrInfo.cpp | ||
MSP430InstrInfo.h | ||
MSP430InstrInfo.td | ||
MSP430ISelDAGToDAG.cpp | ||
MSP430ISelLowering.cpp | ||
MSP430ISelLowering.h | ||
MSP430MachineFunctionInfo.cpp | ||
MSP430MachineFunctionInfo.h | ||
MSP430MCInstLower.cpp | ||
MSP430MCInstLower.h | ||
MSP430RegisterInfo.cpp | ||
MSP430RegisterInfo.h | ||
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.