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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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|---|---|---|
| .. | ||
| MCTargetDesc | ||
| TargetInfo | ||
| CMakeLists.txt | ||
| DelaySlotFiller.cpp | ||
| FPMover.cpp | ||
| Makefile | ||
| README.txt | ||
| Sparc.h | ||
| Sparc.td | ||
| SparcAsmPrinter.cpp | ||
| SparcCallingConv.td | ||
| SparcFrameLowering.cpp | ||
| SparcFrameLowering.h | ||
| SparcInstrFormats.td | ||
| SparcInstrInfo.cpp | ||
| SparcInstrInfo.h | ||
| SparcInstrInfo.td | ||
| SparcISelDAGToDAG.cpp | ||
| SparcISelLowering.cpp | ||
| SparcISelLowering.h | ||
| SparcMachineFunctionInfo.h | ||
| SparcRegisterInfo.cpp | ||
| SparcRegisterInfo.h | ||
| SparcRegisterInfo.td | ||
| SparcSelectionDAGInfo.cpp | ||
| SparcSelectionDAGInfo.h | ||
| SparcSubtarget.cpp | ||
| SparcSubtarget.h | ||
| SparcTargetMachine.cpp | ||
| SparcTargetMachine.h | ||
To-do
-----
* Keep the address of the constant pool in a register instead of forming its
address all of the time.
* We can fold small constant offsets into the %hi/%lo references to constant
pool addresses as well.
* When in V9 mode, register allocate %icc[0-3].
* Add support for isel'ing UMUL_LOHI instead of marking it as Expand.
* Emit the 'Branch on Integer Register with Prediction' instructions. It's
not clear how to write a pattern for this though:
float %t1(int %a, int* %p) {
%C = seteq int %a, 0
br bool %C, label %T, label %F
T:
store int 123, int* %p
br label %F
F:
ret float undef
}
codegens to this:
t1:
save -96, %o6, %o6
1) subcc %i0, 0, %l0
1) bne .LBBt1_2 ! F
nop
.LBBt1_1: ! T
or %g0, 123, %l0
st %l0, [%i1]
.LBBt1_2: ! F
restore %g0, %g0, %g0
retl
nop
1) should be replaced with a brz in V9 mode.
* Same as above, but emit conditional move on register zero (p192) in V9
mode. Testcase:
int %t1(int %a, int %b) {
%C = seteq int %a, 0
%D = select bool %C, int %a, int %b
ret int %D
}
* Emit MULX/[SU]DIVX instructions in V9 mode instead of fiddling
with the Y register, if they are faster.
* Codegen bswap(load)/store(bswap) -> load/store ASI
* Implement frame pointer elimination, e.g. eliminate save/restore for
leaf fns.
* Fill delay slots
* Implement JIT support