Compile to IEC 61131-10 XML - Omron

[DoubleCouponDay]

Based on my discussion post here, I've implemented XML generation as a first class compilation target. For now, the implementation focuses on a subset of Structured Text that is compatible with Sysmac Studio. All that is required is to add the --xml-omron argument. the new plc_xmlgen module is portable enough to handle other specific subsets in the future (eg: CODESYS).

Here is an example of usage:

plc ./source/clampandsaw.st ./source/testallbuiltins.st --xml-omron --generate-external-constructors -i ./externals/stdlib_externals.st -i ./externals/omron_externals.st -L ./compiled -l iec61131std -l libNX1P2 -l ws2_32 -l ntdll -l userenv -o ./compiled/lib_structured_text.xml

For this to work, the builtins of a specific PLC device are compiled into a separate library which can be linked to. As a result, VAR_EXTERNAL and VAR_EXTERNAL CONSTANT had to fixed. Without external references to a stub library, none of the references to built in constants, types, and global functions could compile.

To be clear, Sysmac does not support the following ST syntax:

• no POINTER TO
• no REFERENCE TO
• no WSTRING
• no CLASS
• no INTERFACE
• no ALIAS TO

Unit tests have been added to confirm the feature.

Here is a concise list of changes made in this PR:

New XML export target

• Added compiler/plc_xmlgen crate: xml_gen.rs generator plus a serializer.rs typed node builder for IEC 61131-10 Ed1 XML.
• Added --xml-omron CLI flag and a GenerationParameters struct threaded into codegen.
• Added FormatOption::XML with .xml output naming in plc_project and the codegen participant.
• Added GeneratedModule::persist_to_xml that sits alongside the object/IR/bitcode arms.
• PipelineParticipant::generate now receives &AnnotatedProject and &CompileOptions so the generator can see the AST.

Type rendering for Sysmac

• Emits only StructTypeSpec and EnumTypeWithNamedValueSpec declarations; The two Sysmac actually accepts.
• Resolves aliases, arrays and strings into inline TypeName text instead of declaring them.
• Renders arrays as ARRAY[0..3] OF X, multi-dimensional as ARRAY[0..1,1..3] OF X with no space after the separator.
• Renders strings as String[n], defaulting to a length of 80 characters.
• Recursively resolves nested element types through alias chains, with a hop limit guarding self-referential aliases. The max amount of recursion depth is 16.

VAR_EXTERNAL behaviour

• The initializer lowering now skips VAR_EXTERNAL blocks, so variables from a linked library are no longer initialised a second time.
• Removed the E106 "VAR_EXTERNAL blocks have no effect" warning and its diagnostic entry, doc file and tests.

New diagnostic

• Added E152 (error) for constructs the chosen XML target cannot represent, with a markdown doc page.
• plc_xmlgen scans user types, globals, POU variable blocks and struct members, skipping external linkage and compiler-generated declarations.

Supporting changes

• Added Display impls for AstLiteral, Array, Date, Time, TimeOfDay and DateAndTime so literals can be serialised as text.
• Lowercased VariableBlockType's Display output to match the XML attribute vocabulary.
• Fixed Windows MSVC linking in the stdlib integration test harness (/MD, explicit exports and system libs).
• Documented the new target in book/src/using_rusty.md.

[codecov]

Codecov Report

❌ Patch coverage is 80.03573% with 447 lines in your changes missing coverage. Please review.
✅ Project coverage is 92.90%. Comparing base (1e70538) to head (c0461a8).
⚠️ Report is 223 commits behind head on master.

Files with missing lines	Patch %	Lines
compiler/plc_xmlgen/src/serializer.rs	24.30%	218 Missing ⚠️
compiler/plc_xmlgen/src/xml_gen.rs	83.28%	120 Missing ⚠️
compiler/plc_ast/src/literals.rs	9.75%	37 Missing ⚠️
src/codegen.rs	6.45%	29 Missing ⚠️
libs/stdlib/tests/common/mod.rs	0.00%	13 Missing ⚠️
compiler/plc_driver/src/pipelines.rs	65.38%	9 Missing ⚠️
compiler/plc_driver/src/pipelines/participant.rs	58.82%	7 Missing ⚠️
xtask/src/reporter/sysout.rs	0.00%	4 Missing ⚠️
src/linker.rs	50.00%	2 Missing ⚠️
compiler/plc_ast/src/ast.rs	93.33%	1 Missing ⚠️
... and 7 more

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1896      +/-   ##
==========================================
- Coverage   94.68%   92.90%   -1.78%     
==========================================
  Files         188      197       +9     
  Lines       58726    78883   +20157     
==========================================
+ Hits        55603    73285   +17682     
- Misses       3123     5598    +2475     

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[DoubleCouponDay]

Hey @volsa @ghaith. My Pull Request is finally ready for review. I'm excited to share this with everyone so let me know if you have any feedback. 😄

[DoubleCouponDay]

The 'PR Artifacts' stage of the pipeline is failing with "HttpError: Resource not accessible by integration". How can that be fixed?

Also, the oscat tool in the 'Metrics' stage is failing due to missing support for the INT_TO_STRING built-in function.

[volsa]

Hi, thanks for the contribution!

Just as a heads-up, we have quite a lot going on at the moment so it may take us a little while to find the time to review this.