Rodrigo Mesquita pushed to branch wip/romes/hsmodulename at Glasgow Haskell Compiler / GHC

Commits:

• 2ef80e6b
  by Rodrigo Mesquita at 2026-10-03T12:13:55+01:00

  ttg: HsModuleName in the AST, ModuleName in GHC
  
  This commit makes the AST fully independent from GHC by parsing a
  "module name" as an `HsModuleName (= HText)` rather than constructing an
  `ModuleName (= FastString)` straight away.
  
  In the GHC side, everything remains as a `ModuleName`. We turn AST
  `HsModuleName`s into fast strings with the cheap `mkFastStringShortText`
  when we process the AST for manipulation within the compiler.
  
  There are no performance regressions introduced by this approach.
  
  This is the final piece of #21592
  
  Alternative plans were discussed in
  gitlab.haskell.org/ghc/ghc/-/merge_requests/16546#note_694647,
  but the Simon suggested one won in simplicity and performance when
  compared against my attempt at implementing my original plan of having
  a family `ModuleNameP`.
  

90 changed files:

• compiler/GHC.hs
• compiler/GHC/Builtin/Modules.hs
• compiler/GHC/ByteCode/Asm.hs
• compiler/GHC/ByteCode/Show.hs
• compiler/GHC/Core/DataCon.hs
• compiler/GHC/Core/Opt/CallerCC/Types.hs
• compiler/GHC/Driver/Backpack.hs
• compiler/GHC/Driver/Main/Compile.hs
• compiler/GHC/Driver/Pipeline.hs-boot
• compiler/GHC/Driver/Pipeline/Execute.hs
• compiler/GHC/Driver/Pipeline/Phases.hs
• compiler/GHC/Hs/Doc.hs
• compiler/GHC/Hs/Dump.hs
• compiler/GHC/Hs/Expr.hs
• compiler/GHC/Hs/ImpExp.hs
• compiler/GHC/Hs/Lit.hs
• compiler/GHC/HsToCore/Docs.hs
• compiler/GHC/HsToCore/Quote.hs
• compiler/GHC/Iface/Errors/Types.hs
• compiler/GHC/Iface/Ext/Ast.hs
• compiler/GHC/Iface/Ext/Debug.hs
• compiler/GHC/Iface/Ext/Types.hs
• compiler/GHC/Parser.y
• compiler/GHC/Parser/Errors/Types.hs
• compiler/GHC/Parser/Header.hs
• compiler/GHC/Parser/Lexer.x
• compiler/GHC/Parser/PostProcess.hs
• compiler/GHC/Parser/String.hs
• compiler/GHC/Rename/Env.hs
• compiler/GHC/Rename/Names.hs
• compiler/GHC/Rename/Unbound.hs
• compiler/GHC/StgToJS/Linker/Linker.hs
• compiler/GHC/Tc/Deriv/Generics.hs
• compiler/GHC/Tc/Errors/Types.hs
• compiler/GHC/Tc/Gen/Export.hs
• compiler/GHC/Tc/Module.hs
• compiler/GHC/Tc/Types.hs
• compiler/GHC/Tc/Types/ErrCtxt.hs
• compiler/GHC/ThToHs.hs
• compiler/GHC/Types/Unique.hs
• compiler/GHC/Types/UnresolvedImport.hs
• compiler/GHC/Unit/Home.hs
• compiler/GHC/Unit/Module.hs
• compiler/GHC/Unit/Module/Env.hs
• + compiler/GHC/Unit/Module/Name.hs
• compiler/GHC/Unit/Parser.hs
• compiler/GHC/Unit/Types.hs
• compiler/GHC/Unit/Types.hs-boot
• compiler/GHC/Utils/Binary.hs
• compiler/GHC/Utils/Outputable.hs
• compiler/Language/Haskell/Syntax.hs
• compiler/Language/Haskell/Syntax/Expr.hs
• compiler/Language/Haskell/Syntax/ImpExp.hs
• compiler/Language/Haskell/Syntax/Lit.hs
• compiler/Language/Haskell/Syntax/Module/Name.hs
• compiler/Language/Haskell/Syntax/Text.hs
• compiler/ghc.cabal.in
• ghc/GHCi/UI.hs
• ghc/GHCi/UI/Info.hs
• linters/lint-codes/LintCodes/Static.hs
• testsuite/tests/count-deps/CountDepsAst.stdout
• testsuite/tests/count-deps/CountDepsParser.stdout
• testsuite/tests/ghc-api/downsweep/IncrementalDownsweep.hs
• testsuite/tests/ghc-api/exactprint/T22919.stderr
• testsuite/tests/ghc-api/exactprint/Test20239.stderr
• testsuite/tests/ghc-api/exactprint/ZeroWidthSemi.stderr
• testsuite/tests/haddock/should_compile_flag_haddock/T17544.stderr
• testsuite/tests/haddock/should_compile_flag_haddock/T17544_kw.stderr
• testsuite/tests/haddock/should_compile_flag_haddock/T24221.stderr
• testsuite/tests/hiefile/should_run/T24544.hs
• testsuite/tests/module/mod185.stderr
• testsuite/tests/parser/should_compile/DumpParsedAst.stderr
• testsuite/tests/parser/should_compile/DumpParsedAstComments.stderr
• testsuite/tests/parser/should_compile/DumpRenamedAst.stderr
• testsuite/tests/parser/should_compile/DumpSemis.stderr
• testsuite/tests/parser/should_compile/KindSigs.stderr
• testsuite/tests/parser/should_compile/T14189.stderr
• testsuite/tests/parser/should_compile/T15323.stderr
• testsuite/tests/parser/should_compile/T20452.stderr
• testsuite/tests/parser/should_compile/T20718.stderr
• testsuite/tests/parser/should_compile/T20718b.stderr
• testsuite/tests/parser/should_compile/T20846.stderr
• testsuite/tests/parser/should_compile/T23315/T23315.stderr
• testsuite/tests/printer/AnnotationNoListTuplePuns.stdout
• testsuite/tests/printer/T18791.stderr
• testsuite/tests/printer/Test20297.stdout
• testsuite/tests/printer/Test24533.stdout
• testsuite/tests/profiling/should_run/caller-cc/CallerCcParser.hs
• utils/check-exact/ExactPrint.hs
• utils/haddock/haddock-api/src/Haddock/Backends/Hyperlinker/Renderer.hs

The diff was not included because it is too large.