Julia Dialect tablegen - #62937
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| let cppNamespace = "julia"; | ||
| } | ||
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| def JuliaValue : DialectType<JuliaDialect, "jlvalue"> { |
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@gbaraldi this is already using the dialect type construct that we discussed today.
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| def Safepoint : JuliaOp<"safepoint", | ||
| [Memory<[(readwrite ArgMem), (readwrite InaccessibleMem)]>, | ||
| NoUnwind]> { | ||
| let results = (outs); | ||
| let arguments = (ins Ptr:$signal_page); | ||
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| let summary = "GC safepoint: potential stop-the-world synchronization point"; | ||
| let description = [{ | ||
| Loads from the GC signal page so that stopping the world can be triggered | ||
| by protecting it. | ||
| }]; | ||
| } |
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That's not technically a post GC lowering op, we can have it introduced much earlier
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Specify the Julia-specific pseudo-intrinsics in src/JuliaDialect.td as tblgen-generated op classes. The spec covers both dialect layers: the codegen-level ops (julia.get_pgcstack, julia.get_pgcstack_or_new, julia.gc_loaded) legal until LateLowerGCFrame, and the GC lowering ops (julia.new_gc_frame etc.) produced by LateLowerGCFrame and consumed by FinalLowerGC. The generated declarations carry the same function names, types, and attributes as the handwritten JuliaFunction definitions, so the emitted IR is unchanged. Assisted-by: Claude Code (Fable 5) Claude-Session: https://claude.ai/code/session_013iurq91jyFwfKN8EbrcjL2
Add julia.typeof, julia.blackbox, julia.write_barrier, julia.cancellation_point, julia.gcroot_flush, julia.pointer_from_objref, the julia.call trampoline family, and julia.gc_alloc_obj to JuliaDialect.td. Ops with variadic arguments (write_barrier, the call family) declare a fully-varargs function type. Not represented: llvm.julia.gc_preserve_begin/end (reserved llvm. prefix and token result type, which llvm-dialects cannot express) and jl_alloc_genericmemory_unchecked (a plain runtime call). Assisted-by: Claude Code (Fable 5) Claude-Session: https://claude.ai/code/session_013iurq91jyFwfKN8EbrcjL2
Use the AllocKind and AllocSize traits (GPUOpen-Drivers/llvm-dialects#145) to carry the allockind("alloc") and allocsize(1) attributes of julia.gc_alloc_obj and julia.gc_alloc_bytes in their dialect specification instead of patching them in by hand. Since their size argument type is target dependent (the datalayout's pointer-sized integer), the ops are argument-overloaded and opt into typedArgOverloadDeclaration so that their declarations keep fixed parameters, which allocsize requires. Assisted-by: Claude Code (Fable 5) Claude-Session: https://claude.ai/code/session_01C5vc8DuxsFWuP2UZGN4CCe
Add GCPreserveBegin/GCPreserveEnd op definitions using llvm-dialects' new useLlvmIntrinsicPrefix and TokenTy support: the ops keep their existing `llvm.julia.gc_preserve_*` names (LLVM's IR verifier only allows a token-returning function when it is an unknown intrinsic) and their exact signatures, so the emitted IR is unchanged while the pair gains generated op classes, builders and verifier coverage. Assisted-by: Claude Code (Fable 5) Claude-Session: https://claude.ai/code/session_01C5vc8DuxsFWuP2UZGN4CCe
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This is the meat of the PR, specifying our pseudo-intrinsics as a tablegen file and formalizing attributes and so-forth.
Based on an old hand-written version of #52945 and then updated with Claude.
Assisted-by: Claude
TODO:
julia.xwhich is what llvm-dialects wants.Stack created with GitHub Stacks CLI • Give Feedback 💬