[RISCV] Add Stackmap/Statepoint/Patchpoint support with targets

[Zeavee]

Summary

This patch adds stackmap support for RISC-V with call targets.

Depends on D123496

[Zeavee]

Update tests that do not check data directive using update_llc_test_checks.py.

Avoid RISC-V fixups for StkMapRecord Instruction Offset as they them to be 0.

[jrtc27]

llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.cpp

262

This seems extremely dubious

llvm/lib/Target/RISCV/RISCVAsmPrinter.cpp

143

This seems like a lot of duplication of what already exists for expanding PseudoLI

llvm/lib/Target/RISCV/RISCVInstrInfo.cpp

998

Why initialise to 0? And why have this large scope when it's only for one case?

llvm/test/CodeGen/RISCV/rv64-patchpoint.ll

43

Why the blank lines?

54

These look like some rather machine-generated names; if you don't want to name them, make them %0/1/2/...

102–113

What's the actual point of this test? It seems like a bit of a mess of random arithmetic, pointer casting and memory operations, with a return of 10 for unknown reasons. Are the instructions themselves interesting? If not, make them simpler.

[Zeavee]

llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.cpp

262

I understand, and it is. I tried to look at where exactly the OffsetExpr is reduced to 0 in the fixups, but I did not find it. I will search more.

llvm/lib/Target/RISCV/RISCVAsmPrinter.cpp

143

I will check if emitting a PseudoLI works correctly.

llvm/lib/Target/RISCV/RISCVInstrInfo.cpp

998

I will put it in a smaller scope.

llvm/test/CodeGen/RISCV/rv64-patchpoint.ll

43

They seem to have been added by update_llc_test_checks.py, as I do not have them in previous versions.

102–113

To be honest, I used tests from AArch64, because I thought they would better than test I would create myself. I do not think the instructions themselves are interesting, so I will modify it.

[Zeavee]

Remove useless test and refactor generateInstSeq by adding generateMCInstSeq to avoid code duplication between PseudoLI and Stackmap.

[Zeavee]

Update rv64-patchpoint.ll test.

[Zeavee]

Remove dubious check in RISCVELFStreamer.cpp.

[Zeavee]

Rebased the patch on main. For context, this patch has been used by the LLVM backend of GraalVM's Native Image project in production for around 4 months with no major issues.

[Zeavee]

Hello, now that D123496 has been merged, would it be possible to have a new review on this patch?

[Zeavee]

Gentle ping

[Zeavee]

Friendly ping