Rename Display→MemberRepresentation, dissolve ExtensionAndMiscHelpers, split LoopAndConstantOptimization

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: T-Gro

src/Compiler/TypedTree/TypedTreeOps.Attributes.fs

@@ -1353,6 +1353,42 @@ module internal AttributeHelpers =
     let ValRefIsCompiledAsInstanceMember g (vref: ValRef) =
         ValSpecIsCompiledAsInstance g vref.Deref
 
+    let tryFindExtensionAttribute (g: TcGlobals) (attribs: Attrib list) : Attrib option =
+        tryFindEntityAttribByFlag g WellKnownEntityAttributes.ExtensionAttribute attribs
+
+    let tryAddExtensionAttributeIfNotAlreadyPresentForModule
+        (g: TcGlobals)
+        (tryFindExtensionAttributeIn: (Attrib list -> Attrib option) -> Attrib option)
+        (moduleEntity: Entity)
+        : Entity =
+        if Option.isSome (tryFindExtensionAttribute g moduleEntity.Attribs) then
+            moduleEntity
+        else
+            match tryFindExtensionAttributeIn (tryFindExtensionAttribute g) with
+            | None -> moduleEntity
+            | Some extensionAttrib ->
+                { moduleEntity with
+                    entity_attribs = moduleEntity.EntityAttribs.Add(extensionAttrib, WellKnownEntityAttributes.ExtensionAttribute)
+                }
+
+    let tryAddExtensionAttributeIfNotAlreadyPresentForType
+        (g: TcGlobals)
+        (tryFindExtensionAttributeIn: (Attrib list -> Attrib option) -> Attrib option)
+        (moduleOrNamespaceTypeAccumulator: ModuleOrNamespaceType ref)
+        (typeEntity: Entity)
+        : Entity =
+        if Option.isSome (tryFindExtensionAttribute g typeEntity.Attribs) then
+            typeEntity
+        else
+            match tryFindExtensionAttributeIn (tryFindExtensionAttribute g) with
+            | None -> typeEntity
+            | Some extensionAttrib ->
+                moduleOrNamespaceTypeAccumulator.Value.AllEntitiesByLogicalMangledName.TryFind(typeEntity.LogicalName)
+                |> Option.iter (fun e ->
+                    e.entity_attribs <- e.EntityAttribs.Add(extensionAttrib, WellKnownEntityAttributes.ExtensionAttribute))
+
+                typeEntity
+
 [<AutoOpen>]
 module internal ByrefAndSpanHelpers =
 

src/Compiler/TypedTree/TypedTreeOps.Attributes.fsi

@@ -293,6 +293,23 @@ module internal AttributeHelpers =
 
     val ValRefIsCompiledAsInstanceMember: TcGlobals -> ValRef -> bool
 
+    val tryFindExtensionAttribute: g: TcGlobals -> attribs: Attrib list -> Attrib option
+
+    /// Add an System.Runtime.CompilerServices.ExtensionAttribute to the module Entity if found via predicate and not already present.
+    val tryAddExtensionAttributeIfNotAlreadyPresentForModule:
+        g: TcGlobals ->
+        tryFindExtensionAttributeIn: ((Attrib list -> Attrib option) -> Attrib option) ->
+        moduleEntity: Entity ->
+            Entity
+
+    /// Add an System.Runtime.CompilerServices.ExtensionAttribute to the type Entity if found via predicate and not already present.
+    val tryAddExtensionAttributeIfNotAlreadyPresentForType:
+        g: TcGlobals ->
+        tryFindExtensionAttributeIn: ((Attrib list -> Attrib option) -> Attrib option) ->
+        moduleOrNamespaceTypeAccumulator: ModuleOrNamespaceType ref ->
+        typeEntity: Entity ->
+            Entity
+
 
 [<AutoOpen>]
 module internal ByrefAndSpanHelpers =

src/Compiler/TypedTree/TypedTreeOps.ExprConstruction.fs

@@ -1314,6 +1314,40 @@ module internal TypeTesters =
         else
             isResumableCodeTy g ty
 
+    let ComputeUseMethodImpl g (v: Val) =
+        v.ImplementedSlotSigs
+        |> List.exists (fun slotsig ->
+            let oty = slotsig.DeclaringType
+            let otcref = tcrefOfAppTy g oty
+            let tcref = v.MemberApparentEntity
+
+            // REVIEW: it would be good to get rid of this special casing of Compare and GetHashCode
+            isInterfaceTy g oty
+            &&
+
+            (let isCompare =
+                tcref.GeneratedCompareToValues.IsSome
+                && (typeEquiv g oty g.mk_IComparable_ty
+                    || tyconRefEq g g.system_GenericIComparable_tcref otcref)
+
+             not isCompare)
+            &&
+
+            (let isGenericEquals =
+                tcref.GeneratedHashAndEqualsWithComparerValues.IsSome
+                && tyconRefEq g g.system_GenericIEquatable_tcref otcref
+
+             not isGenericEquals)
+            &&
+
+            (let isStructural =
+                (tcref.GeneratedCompareToWithComparerValues.IsSome
+                 && typeEquiv g oty g.mk_IStructuralComparable_ty)
+                || (tcref.GeneratedHashAndEqualsWithComparerValues.IsSome
+                    && typeEquiv g oty g.mk_IStructuralEquatable_ty)
+
+             not isStructural))
+
 
 [<AutoOpen>]
 module internal CommonContainers =

src/Compiler/TypedTree/TypedTreeOps.ExprConstruction.fsi

@@ -645,6 +645,9 @@ module internal TypeTesters =
     /// The delegate type ResumableCode, or any function returning this a delegate type
     val isReturnsResumableCodeTy: TcGlobals -> TType -> bool
 
+    /// Determine if a value is a method implementing an interface dispatch slot using a private method impl
+    val ComputeUseMethodImpl: g: TcGlobals -> v: Val -> bool
+
 [<AutoOpen>]
 module internal CommonContainers =
 

src/Compiler/TypedTree/TypedTreeOps.FreeVars.fs

@@ -493,7 +493,7 @@ module internal FreeTypeVars =
         accFreeInTypesLeftToRight g false true emptyFreeTyparsLeftToRight ty |> List.rev
 
 [<AutoOpen>]
-module internal Display =
+module internal MemberRepresentation =
 
     //--------------------------------------------------------------------------
     // Values representing member functions on F# types

src/Compiler/TypedTree/TypedTreeOps.FreeVars.fsi

@@ -117,7 +117,7 @@ module internal FreeTypeVars =
     val freeInModuleTy: ModuleOrNamespaceType -> FreeTyvars
 
 [<AutoOpen>]
-module internal Display =
+module internal MemberRepresentation =
 
     val GetMemberTypeInFSharpForm:
         TcGlobals -> SynMemberFlags -> ValReprInfo -> TType -> range -> Typars * CurriedArgInfos * TType * ArgReprInfo

src/Compiler/TypedTree/TypedTreeOps.Remap.fs

@@ -1676,4 +1676,20 @@ module internal TypeEquivalence =
     let measureEquiv g m1 m2 =
         measureAEquiv g TypeEquivEnv.EmptyIgnoreNulls m1 m2
 
+    /// An immutable mapping from witnesses to some data.
+    ///
+    /// Note: this uses an immutable HashMap/Dictionary with an IEqualityComparer that captures TcGlobals, see EmptyTraitWitnessInfoHashMap
+    type TraitWitnessInfoHashMap<'T> = ImmutableDictionary<TraitWitnessInfo, 'T>
+
+    /// Create an empty immutable mapping from witnesses to some data
+    let EmptyTraitWitnessInfoHashMap g : TraitWitnessInfoHashMap<'T> =
+        ImmutableDictionary.Create(
+            { new IEqualityComparer<_> with
+                member _.Equals(a, b) =
+                    nullSafeEquality a b (fun a b -> traitKeysAEquiv g TypeEquivEnv.EmptyIgnoreNulls a b)
+
+                member _.GetHashCode(a) = hash a.MemberName
+            }
+        )
+
 

src/Compiler/TypedTree/TypedTreeOps.Remap.fsi

@@ -559,4 +559,12 @@ module internal TypeEquivalence =
     /// Check the equivalence of two units-of-measure
     val measureEquiv: TcGlobals -> Measure -> Measure -> bool
 
+    /// An immutable mapping from witnesses to some data.
+    ///
+    /// Note: this uses an immutable HashMap/Dictionary with an IEqualityComparer that captures TcGlobals, see EmptyTraitWitnessInfoHashMap
+    type TraitWitnessInfoHashMap<'T> = ImmutableDictionary<TraitWitnessInfo, 'T>
+
+    /// Create an empty immutable mapping from witnesses to some data
+    val EmptyTraitWitnessInfoHashMap: TcGlobals -> TraitWitnessInfoHashMap<'T>
+
 

src/Compiler/TypedTree/TypedTreeOps.Remapping.fs

@@ -724,6 +724,43 @@ module internal SignatureOps =
                         seqEntity.entity_flags.IsStructRecordOrUnionType
                     )))
 
+    /// Matches a ModuleOrNamespaceContents that is empty from a signature printing point of view.
+    /// Signatures printed via the typed tree in NicePrint don't print TMDefOpens or TMDefDo.
+    /// This will match anything that does not have any types or bindings.
+    [<return: Struct>]
+    let (|EmptyModuleOrNamespaces|_|) (moduleOrNamespaceContents: ModuleOrNamespaceContents) =
+        match moduleOrNamespaceContents with
+        | TMDefs(defs = defs) ->
+            let mdDefsLength =
+                defs
+                |> List.count (function
+                    | ModuleOrNamespaceContents.TMDefRec _
+                    | ModuleOrNamespaceContents.TMDefs _ -> true
+                    | _ -> false)
+
+            let emptyModuleOrNamespaces =
+                defs
+                |> List.choose (function
+                    | ModuleOrNamespaceContents.TMDefRec _ as defRec
+                    | ModuleOrNamespaceContents.TMDefs(defs = [ ModuleOrNamespaceContents.TMDefRec _ as defRec ]) ->
+                        match defRec with
+                        | TMDefRec(bindings = [ ModuleOrNamespaceBinding.Module(mspec, ModuleOrNamespaceContents.TMDefs(defs = defs)) ]) ->
+                            defs
+                            |> List.forall (function
+                                | ModuleOrNamespaceContents.TMDefOpens _
+                                | ModuleOrNamespaceContents.TMDefDo _
+                                | ModuleOrNamespaceContents.TMDefRec(isRec = true; tycons = []; bindings = []) -> true
+                                | _ -> false)
+                            |> fun isEmpty -> if isEmpty then Some mspec else None
+                        | _ -> None
+                    | _ -> None)
+
+            if mdDefsLength = emptyModuleOrNamespaces.Length then
+                ValueSome emptyModuleOrNamespaces
+            else
+                ValueNone
+        | _ -> ValueNone
+
 [<AutoOpen>]
 module internal ExprFreeVars =
 

src/Compiler/TypedTree/TypedTreeOps.Remapping.fsi

@@ -121,6 +121,13 @@ module internal SignatureOps =
     /// Updates the IsPrefixDisplay to false for the Microsoft.FSharp.Collections.seq`1 entity
     val updateSeqTypeIsPrefix: fsharpCoreMSpec: ModuleOrNamespace -> unit
 
+    /// Matches a ModuleOrNamespaceContents that is empty from a signature printing point of view.
+    /// Signatures printed via the typed tree in NicePrint don't print TMDefOpens or TMDefDo.
+    /// This will match anything that does not have any types or bindings.
+    [<return: Struct>]
+    val (|EmptyModuleOrNamespaces|_|):
+        moduleOrNamespaceContents: ModuleOrNamespaceContents -> ModuleOrNamespace list voption
+
 [<AutoOpen>]
 module internal ExprFreeVars =