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b35552d440
The first problem to fix is to stop creating synthetic *Table_gen targets next to all of the LLVM libraries. These had no real effect as CMake specifies that add_custom_command(OUTPUT ...) directives (what the 'tablegen(...)' stuff expands to) are implicitly added as dependencies to all the rules in that CMakeLists.txt. These synthetic rules started to cause problems as we started more and more heavily using tablegen files from *subdirectories* of the one where they were generated. Within those directories, the set of tablegen outputs was still available and so these synthetic rules added them as dependencies of those subdirectories. However, they were no longer properly associated with the custom command to generate them. Most of the time this "just worked" because something would get to the parent directory first, and run tablegen there. Once run, the files existed and the build proceeded happily. However, as more and more subdirectories have started using this, the probability of this failing to happen has increased. Recently with the MC refactorings, it became quite common for me when touching a large enough number of targets. To add insult to injury, several of the backends *tried* to fix this by adding explicit dependencies back to the parent directory's tablegen rules, but those dependencies didn't work as expected -- they weren't forming a linear chain, they were adding another thread in the race. This patch removes these synthetic rules completely, and adds a much simpler function to declare explicitly that a collection of tablegen'ed files are referenced by other libraries. From that, we can add explicit dependencies from the smaller libraries (such as every architectures Desc library) on this and correctly form a linear sequence. All of the backends are updated to use it, sometimes replacing the existing attempt at adding a dependency, sometimes adding a previously missing dependency edge. Please let me know if this causes any problems, but it fixes a rather persistent and problematic source of build flakiness on our end. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136023 91177308-0d34-0410-b5e6-96231b3b80d8 |
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| .. | ||
| InstPrinter | ||
| MCTargetDesc | ||
| TargetInfo | ||
| CMakeLists.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.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.