Convert ExpandPeerMacroRequest to use split caching

Author: slavapestov

include/swift/AST/Decl.h

@@ -357,7 +357,7 @@ class alignas(1 << DeclAlignInBits) Decl : public ASTAllocated<Decl> {
   // for the inline bitfields.
   union { uint64_t OpaqueBits;
 
-  SWIFT_INLINE_BITFIELD_BASE(Decl, bitmax(NumDeclKindBits,8)+1+1+1+1+1+1+1+1+1+1,
+  SWIFT_INLINE_BITFIELD_BASE(Decl, bitmax(NumDeclKindBits,8)+1+1+1+1+1+1+1+1+1+1+1,
     Kind : bitmax(NumDeclKindBits,8),
 
     /// Whether this declaration is invalid.
@@ -394,6 +394,10 @@ class alignas(1 << DeclAlignInBits) Decl : public ASTAllocated<Decl> {
     /// request returned an empty array.
     NoMemberAttributeMacros : 1,
 
+    /// True if we're in the common case where the ExpandPeerMacroRequest
+    /// request returned an empty array.
+    NoPeerMacros : 1,
+
     /// True if we're in the common case where the GlobalActorAttributeRequest
     /// request returned a pair of null pointers.
     NoGlobalActorAttribute : 1,
@@ -519,7 +523,7 @@ class alignas(1 << DeclAlignInBits) Decl : public ASTAllocated<Decl> {
 
     /// Whether this function is a distributed thunk for a distributed
     /// function or computed property.
-    DistributedThunk: 1
+    DistributedThunk : 1
   );
 
   SWIFT_INLINE_BITFIELD(FuncDecl, AbstractFunctionDecl,
@@ -843,6 +847,7 @@ class alignas(1 << DeclAlignInBits) Decl : public ASTAllocated<Decl> {
   friend class DeclDeserializer;
   friend class RawCommentRequest;
   friend class ExpandMemberAttributeMacros;
+  friend class ExpandPeerMacroRequest;
   friend class GlobalActorAttributeRequest;
   friend class SPIGroupsRequest;
 
@@ -871,6 +876,14 @@ class alignas(1 << DeclAlignInBits) Decl : public ASTAllocated<Decl> {
     Bits.Decl.NoMemberAttributeMacros = true;
   }
 
+  bool hasNoPeerMacros() const {
+    return Bits.Decl.NoPeerMacros;
+  }
+
+  void setHasNoPeerMacros() {
+    Bits.Decl.NoPeerMacros = true;
+  }
+
   bool hasNoGlobalActorAttribute() const {
     return Bits.Decl.NoGlobalActorAttribute;
   }

include/swift/AST/TypeCheckRequests.h

@@ -4608,7 +4608,8 @@ class CompilerPluginLoadRequest
 class ExpandPeerMacroRequest
     : public SimpleRequest<ExpandPeerMacroRequest,
                            ArrayRef<unsigned>(Decl *),
-                           RequestFlags::Cached> {
+                           RequestFlags::SeparatelyCached |
+                           RequestFlags::SplitCached> {
 public:
   using SimpleRequest::SimpleRequest;
 
@@ -4618,7 +4619,11 @@ class ExpandPeerMacroRequest
   ArrayRef<unsigned> evaluate(Evaluator &evaluator, Decl *decl) const;
 
 public:
+  // Separate caching.
   bool isCached() const { return true; }
+  std::optional<ArrayRef<unsigned>> getCachedResult() const;
+  void cacheResult(ArrayRef<unsigned> result) const;
+
   void diagnoseCycle(DiagnosticEngine &diags) const;
   void noteCycleStep(DiagnosticEngine &diags) const;
 };

include/swift/AST/TypeCheckerTypeIDZone.def

@@ -516,7 +516,7 @@ SWIFT_REQUEST(TypeChecker, ExpandSynthesizedMemberMacroRequest,
               Cached, NoLocationInfo)
 SWIFT_REQUEST(TypeChecker, ExpandPeerMacroRequest,
               ArrayRef<unsigned>(Decl *),
-              Cached, NoLocationInfo)
+              SeparatelyCached | SplitCached, NoLocationInfo)
 SWIFT_REQUEST(TypeChecker, ExpandPreambleMacroRequest,
               ArrayRef<unsigned>(AbstractFunctionDecl *),
               Cached, NoLocationInfo)

lib/AST/TypeCheckRequests.cpp

@@ -2231,6 +2231,30 @@ void ExpandSynthesizedMemberMacroRequest::noteCycleStep(DiagnosticEngine &diags)
   }
 }
 
+//----------------------------------------------------------------------------//
+// ExpandPeerMacroRequest computation.
+//----------------------------------------------------------------------------//
+
+std::optional<ArrayRef<unsigned>> ExpandPeerMacroRequest::getCachedResult() const {
+  auto decl = std::get<0>(getStorage());
+  if (decl->hasNoPeerMacros())
+    return ArrayRef<unsigned>();
+
+  return decl->getASTContext().evaluator.getCachedNonEmptyOutput(*this);
+}
+
+void ExpandPeerMacroRequest::cacheResult(ArrayRef<unsigned> result) const {
+  auto decl = std::get<0>(getStorage());
+
+  if (result.empty()) {
+    decl->setHasNoPeerMacros();
+    return;
+  }
+
+  decl->getASTContext().evaluator
+      .cacheNonEmptyOutput<ExpandPeerMacroRequest>(*this, std::move(result));
+}
+
 void ExpandPeerMacroRequest::diagnoseCycle(DiagnosticEngine &diags) const {
   auto decl = std::get<0>(getStorage());
   if (auto value = dyn_cast<ValueDecl>(decl)) {
@@ -2380,6 +2404,10 @@ void UniqueUnderlyingTypeSubstitutionsRequest::cacheResult(
       ->LazySemanticInfo.UniqueUnderlyingTypeComputed = true;
 }
 
+//----------------------------------------------------------------------------//
+// ExpandPreambleMacroRequest computation.
+//----------------------------------------------------------------------------//
+
 void ExpandPreambleMacroRequest::diagnoseCycle(DiagnosticEngine &diags) const {
   auto decl = std::get<0>(getStorage());
   diags.diagnose(decl->getLoc(),
@@ -2396,6 +2424,10 @@ void ExpandPreambleMacroRequest::noteCycleStep(DiagnosticEngine &diags) const {
                  decl->getName());
 }
 
+//----------------------------------------------------------------------------//
+// ExpandBodyMacroRequest computation.
+//----------------------------------------------------------------------------//
+
 void ExpandBodyMacroRequest::diagnoseCycle(DiagnosticEngine &diags) const {
   auto decl = std::get<0>(getStorage());
   diags.diagnose(decl->getLoc(),