Reuse typechecking results - stage 1

Author: psfinaki

docs/release-notes/.FSharp.Compiler.Service/9.0.200.md

@@ -24,6 +24,7 @@
 
 ### Added
 
+* New flag `--reusetypecheckingresults`, for skipping recompilation in some cases
 * Let `dotnet fsi --help` print a link to the documentation website. ([PR #18006](https://github.com/dotnet/fsharp/pull/18006))
 * Deprecate places where `seq` can be omitted. ([Language suggestion #1033](https://github.com/fsharp/fslang-suggestions/issues/1033), [PR #17772](https://github.com/dotnet/fsharp/pull/17772))
 * Support literal attribute on decimals ([PR #17769](https://github.com/dotnet/fsharp/pull/17769))

src/Compiler/Driver/CompilerConfig.fs

@@ -444,6 +444,11 @@ type TypeCheckingMode =
     | Sequential
     | Graph
 
+[<RequireQualifiedAccess>]
+type ReuseTcResults =
+    | On
+    | Off
+
 [<RequireQualifiedAccess>]
 type TypeCheckingConfig =
     {
@@ -651,6 +656,8 @@ type TcConfigBuilder =
 
         mutable parallelReferenceResolution: ParallelReferenceResolution
 
+        mutable reuseTcResults: ReuseTcResults
+
         mutable captureIdentifiersWhenParsing: bool
 
         mutable typeCheckingConfig: TypeCheckingConfig
@@ -660,6 +667,8 @@ type TcConfigBuilder =
         mutable realsig: bool
 
         mutable compilationMode: TcGlobals.CompilationMode
+
+        mutable cmdLineArgs: string array
     }
 
     // Directories to start probing in
@@ -861,6 +870,7 @@ type TcConfigBuilder =
             xmlDocInfoLoader = None
             exiter = QuitProcessExiter
             parallelReferenceResolution = ParallelReferenceResolution.Off
+            reuseTcResults = ReuseTcResults.Off
             captureIdentifiersWhenParsing = false
             typeCheckingConfig =
                 {
@@ -875,6 +885,7 @@ type TcConfigBuilder =
             realsig = false
             strictIndentation = None
             compilationMode = TcGlobals.CompilationMode.Unset
+            cmdLineArgs = [||]
         }
 
     member tcConfigB.FxResolver =
@@ -1415,11 +1426,13 @@ type TcConfig private (data: TcConfigBuilder, validate: bool) =
     member _.xmlDocInfoLoader = data.xmlDocInfoLoader
     member _.exiter = data.exiter
     member _.parallelReferenceResolution = data.parallelReferenceResolution
+    member _.reuseTcResults = data.reuseTcResults
     member _.captureIdentifiersWhenParsing = data.captureIdentifiersWhenParsing
     member _.typeCheckingConfig = data.typeCheckingConfig
     member _.dumpSignatureData = data.dumpSignatureData
     member _.realsig = data.realsig
     member _.compilationMode = data.compilationMode
+    member _.cmdLineArgs = data.cmdLineArgs
 
     static member Create(builder, validate) =
         use _ = UseBuildPhase BuildPhase.Parameter

src/Compiler/Driver/CompilerConfig.fsi

@@ -208,6 +208,11 @@ type ParallelReferenceResolution =
     | On
     | Off
 
+[<RequireQualifiedAccess>]
+type ReuseTcResults =
+    | On
+    | Off
+
 /// Determines the algorithm used for type-checking.
 [<RequireQualifiedAccess>]
 type TypeCheckingMode =
@@ -519,6 +524,8 @@ type TcConfigBuilder =
 
         mutable parallelReferenceResolution: ParallelReferenceResolution
 
+        mutable reuseTcResults: ReuseTcResults
+
         mutable captureIdentifiersWhenParsing: bool
 
         mutable typeCheckingConfig: TypeCheckingConfig
@@ -528,6 +535,8 @@ type TcConfigBuilder =
         mutable realsig: bool
 
         mutable compilationMode: TcGlobals.CompilationMode
+
+        mutable cmdLineArgs: string array
     }
 
     static member CreateNew:
@@ -899,6 +908,8 @@ type TcConfig =
 
     member parallelReferenceResolution: ParallelReferenceResolution
 
+    member reuseTcResults: ReuseTcResults
+
     member captureIdentifiersWhenParsing: bool
 
     member typeCheckingConfig: TypeCheckingConfig
@@ -909,6 +920,8 @@ type TcConfig =
 
     member compilationMode: TcGlobals.CompilationMode
 
+    member cmdLineArgs: string array
+
 /// Represents a computation to return a TcConfig. Normally this is just a constant immutable TcConfig,
 /// but for F# Interactive it may be based on an underlying mutable TcConfigBuilder.
 [<Sealed>]

src/Compiler/Driver/CompilerImports.fs

@@ -337,6 +337,54 @@ let EncodeOptimizationData (tcGlobals, tcConfig: TcConfig, outfile, exportRemapp
     else
         []
 
+let GetTypecheckingData (file, ilScopeRef, ilModule, byteReaderA, byteReaderB) =
+
+    let memA = byteReaderA ()
+
+    let memB =
+        match byteReaderB with
+        | None -> ByteMemory.Empty.AsReadOnly()
+        | Some br -> br ()
+
+    unpickleObjWithDanglingCcus file ilScopeRef ilModule unpickleTcInfo memA memB
+
+let WriteTypecheckingData (tcConfig: TcConfig, tcGlobals, fileName, inMem, ccu, tcInfo) =
+
+    // need to understand the naming and if we even want two resources here...
+    let rName = "FSharpTypecheckingData"
+    let rNameB = "FSharpTypecheckingDataB"
+
+    PickleToResource
+        inMem
+        fileName
+        tcGlobals
+        tcConfig.compressMetadata
+        ccu
+        (rName + ccu.AssemblyName)
+        (rNameB + ccu.AssemblyName)
+        pickleTcInfo
+        tcInfo
+
+let EncodeTypecheckingData (tcConfig: TcConfig, tcGlobals, generatedCcu, outfile, isIncrementalBuild, tcInfo) =
+    let r1, r2 =
+        WriteTypecheckingData(
+            tcConfig, 
+            tcGlobals,
+            outfile, 
+            isIncrementalBuild, 
+            generatedCcu,
+            tcInfo)
+
+    let resources =
+        [
+            r1
+            match r2 with
+            | None -> ()
+            | Some r -> r
+        ]
+
+    resources
+
 exception AssemblyNotResolved of originalName: string * range: range
 
 exception MSBuildReferenceResolutionWarning of message: string * warningCode: string * range: range
@@ -901,17 +949,17 @@ type TcAssemblyResolutions(tcConfig: TcConfig, results: AssemblyResolution list,
 
         for UnresolvedAssemblyReference (referenceText, _ranges) in unresolved do
             if referenceText.Contains("mscorlib") then
-                Debug.Assert(false, sprintf "whoops, did not resolve mscorlib: '%s'%s" referenceText addedText)
+                //Debug.Assert(false, sprintf "whoops, did not resolve mscorlib: '%s'%s" referenceText addedText)
                 itFailed <- true
 
         for x in frameworkDLLs do
             if not (FileSystem.IsPathRootedShim(x.resolvedPath)) then
-                Debug.Assert(false, sprintf "frameworkDLL should be absolute path: '%s'%s" x.resolvedPath addedText)
+                //Debug.Assert(false, sprintf "frameworkDLL should be absolute path: '%s'%s" x.resolvedPath addedText)
                 itFailed <- true
 
         for x in nonFrameworkReferences do
             if not (FileSystem.IsPathRootedShim(x.resolvedPath)) then
-                Debug.Assert(false, sprintf "nonFrameworkReference should be absolute path: '%s'%s" x.resolvedPath addedText)
+                //Debug.Assert(false, sprintf "nonFrameworkReference should be absolute path: '%s'%s" x.resolvedPath addedText)
                 itFailed <- true
 
         if itFailed then

src/Compiler/Driver/CompilerImports.fsi

@@ -19,6 +19,7 @@ open FSharp.Compiler.TcGlobals
 open FSharp.Compiler.BuildGraph
 open FSharp.Compiler.IO
 open FSharp.Compiler.Text
+open FSharp.Compiler.TypedTreePickle
 open FSharp.Core.CompilerServices
 
 #if !NO_TYPEPROVIDERS
@@ -71,6 +72,23 @@ val EncodeOptimizationData:
     isIncrementalBuild: bool ->
         ILResource list
 
+val GetTypecheckingData:
+    file: string *
+    ilScopeRef: ILScopeRef *
+    ilModule: ILModuleDef option *
+    byteReaderA: (unit -> ReadOnlyByteMemory) *
+    byteReaderB: (unit -> ReadOnlyByteMemory) option ->
+        PickledDataWithReferences<PickledTcInfo>
+
+val EncodeTypecheckingData:
+    tcConfig: TcConfig *
+    tcGlobals: TcGlobals *
+    generatedCcu: CcuThunk *
+    outfile: string *
+    isIncrementalBuild: bool *
+    tcInfo: PickledTcInfo ->
+        ILResource list
+
 [<RequireQualifiedAccess>]
 type ResolveAssemblyReferenceMode =
     | Speculative

src/Compiler/Driver/CompilerOptions.fs

@@ -1388,6 +1388,14 @@ let advancedFlagsFsc tcConfigB =
             None,
             Some(FSComp.SR.optsEmitDebugInfoInQuotations (formatOptionSwitch tcConfigB.emitDebugInfoInQuotations))
         )
+
+        CompilerOption(
+            "reusetypecheckingresults",
+            tagNone,
+            OptionUnit(fun () -> tcConfigB.reuseTcResults <- ReuseTcResults.On),
+            None,
+            Some(FSComp.SR.optsReuseTcResults ())
+        )
     ]
 
 // OptionBlock: Internal options (test use only)

src/Compiler/Driver/ParseAndCheckInputs.fs

@@ -31,6 +31,7 @@ open FSharp.Compiler.LexerStore
 open FSharp.Compiler.Lexhelp
 open FSharp.Compiler.NameResolution
 open FSharp.Compiler.ParseHelpers
+open FSharp.Compiler.ReuseTcResults
 open FSharp.Compiler.Syntax
 open FSharp.Compiler.SyntaxTrivia
 open FSharp.Compiler.Syntax.PrettyNaming
@@ -1960,6 +1961,10 @@ let CheckMultipleInputsUsingGraphMode
         partialResults, tcState)
 
 let CheckClosedInputSet (ctok, checkForErrors, tcConfig: TcConfig, tcImports, tcGlobals, prefixPathOpt, tcState, eagerFormat, inputs) =
+
+    if tcConfig.reuseTcResults = ReuseTcResults.On then
+        CachingDriver(tcConfig).TryReuseTcResults(inputs)
+
     // tcEnvAtEndOfLastFile is the environment required by fsi.exe when incrementally adding definitions
     let results, tcState =
         match tcConfig.typeCheckingConfig.Mode with