[vchuravy]

Stacked on #23. This is the plan's debug-info item. GPUCompiler needs it because its error messages build backtraces from !dbg locations.

CodegenConfig(; debug_info) selects the debug information, as the debug_info_kind of Julia's CodegenParams does: :none (the default), or line tables in a compile unit of emission kind :line_tables, :directives (what GPUCompiler uses for PTX) or :full.

• Compile unit: DW_LANG_Julia, producer julia, file julia in ., all as native code's. The module gets the Debug Info Version and Dwarf Version flags if it lacks them.
• Subprograms: every function has one, named after its method, with the LLVM name as its linkage name. That includes entries, stubs and C-callable wrappers; their instructions, including calls to the functions they inline, get the function's line. This keeps LLVM's verifier satisfied when bodies are inlined into their entries.
• Statement locations: every statement gets its line, with the functions inlined at it as inlined frames (inlinedAt chains, from Base.IRShow.buildLineInfoNode). Inlined methods get their own subprograms.
• Not included: no information about variables or types.

codegen_output finalizes the DIBuilder.

Tests (test/debuginfo.jl)

• FileCheck of the compile unit, the file, subprograms and call locations;
• inlined frames;
• entries having subprograms;
• no !dbg without debug info;
• differential runs with debug info;
• the three emission kinds, and invalid values.

I also ran the whole suite once with debug info enabled in the test configuration (not kept): it passes apart from the one test that expects no debug info. LLVM's verifier and Julia's pipeline accept every module.

Tested locally with julia +1.12, +1.13 and +nightly: 5960, 5966 and 5965 tests pass.

🤖 Generated with Claude Code