[PATCH] D92950: [WebAssembly] [lld] Exclude COMDAT sections

[Derek Schuff via Phabricator via llvm-commits]

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dschuff retitled this revision from "[WIP] WebAssembly Linker change for COMDAT sections" to "WebAssembly Linker change for COMDAT sections".
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dschuff retitled this revision from "WebAssembly Linker change for COMDAT sections" to "[WebAssembly] [lld] Exclude COMDAT sections".
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- add tests


dschuff added a comment.

- update. sections seem to work, functions fishy


sbc100 added a comment.

lgtm... Aside from the broken test.


dschuff added a comment.

- rebase, remove debug print and don't test functions



================
Comment at: lld/wasm/InputFiles.cpp:439
+               << chunk->getName() << " comdat " << c << " excluded "
+               << !keptComdats[c] << "\n";
   return !keptComdats[c];
----------------
Remove debugging?


================
Comment at: lld/wasm/InputFiles.cpp:498
+    // Need to return null if discarded here? data and func only do that when
+    // binding is not local.
+    if (section->discarded)
----------------
But the assert above shows that all section symbols are by definition local binding.    You can't ever reference section symbol from another object file.. they are always internal to given object.


Allow exclusion/discarding of custom sections with COMDAT groups.
It piggybacks on the existing COMDAT-handling code, but applies to custom sections as well.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D92950

Files:
  lld/test/wasm/Inputs/comdat1.s
  lld/test/wasm/Inputs/comdat2.s
  lld/test/wasm/comdat-sections.s
  lld/wasm/InputChunks.h
  lld/wasm/InputFiles.cpp
  lld/wasm/OutputSections.cpp
  lld/wasm/Writer.cpp

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