[SIL] InitAccessors: Reference a field that assign_or_init is associated with

The field removes the need to dig through init accessor reference
to find what stored properties and handled by the instruction.

Author: xedin

include/swift/SIL/SILBuilder.h

@@ -956,13 +956,15 @@ class SILBuilder {
   }
 
   AssignOrInitInst *createAssignOrInit(SILLocation Loc,
+                                       VarDecl *Property,
                                        SILValue Self,
                                        SILValue Src,
                                        SILValue Initializer,
                                        SILValue Setter,
                                        AssignOrInitInst::Mode Mode) {
-    return insert(new (getModule()) AssignOrInitInst(
-        getSILDebugLocation(Loc), Self, Src, Initializer, Setter, Mode));
+    return insert(new (getModule())
+                      AssignOrInitInst(getSILDebugLocation(Loc), Property, Self,
+                                       Src, Initializer, Setter, Mode));
   }
 
   StoreBorrowInst *createStoreBorrow(SILLocation Loc, SILValue Src,

include/swift/SIL/SILCloner.h

@@ -1356,6 +1356,7 @@ void SILCloner<ImplClass>::visitAssignOrInitInst(AssignOrInitInst *Inst) {
   recordClonedInstruction(
       Inst, getBuilder().createAssignOrInit(
                 getOpLocation(Inst->getLoc()),
+                Inst->getProperty(),
                 getOpValue(Inst->getSelf()),
                 getOpValue(Inst->getSrc()),
                 getOpValue(Inst->getInitializer()),

include/swift/SIL/SILInstruction.h

@@ -4820,6 +4820,9 @@ class AssignOrInitInst
 
   FixedOperandList<4> Operands;
 
+  /// Property the init accessor is associated with.
+  VarDecl *Property;
+
   /// Marks all of the properties in `initializes(...)` list that
   /// have been initialized before this intruction to help Raw SIL
   /// lowering to emit destroys.
@@ -4838,10 +4841,12 @@ class AssignOrInitInst
   };
 
 private:
-  AssignOrInitInst(SILDebugLocation DebugLoc, SILValue Self, SILValue Src,
-                   SILValue Initializer, SILValue Setter, Mode mode);
+  AssignOrInitInst(SILDebugLocation DebugLoc, VarDecl *P, SILValue Self,
+                   SILValue Src, SILValue Initializer, SILValue Setter,
+                   Mode mode);
 
 public:
+  VarDecl *getProperty() const { return Property; }
   SILValue getSelf() const { return Operands[0].get(); }
   SILValue getSrc() const { return Operands[1].get(); }
   SILValue getInitializer() const { return Operands[2].get(); }

lib/SIL/IR/SILInstructions.cpp

@@ -1259,12 +1259,13 @@ AssignByWrapperInst::AssignByWrapperInst(SILDebugLocation Loc,
   sharedUInt8().AssignByWrapperInst.mode = uint8_t(mode);
 }
 
-AssignOrInitInst::AssignOrInitInst(SILDebugLocation Loc, SILValue Self,
-                                   SILValue Src, SILValue Initializer,
-                                   SILValue Setter, AssignOrInitInst::Mode Mode)
+AssignOrInitInst::AssignOrInitInst(SILDebugLocation Loc, VarDecl *P,
+                                   SILValue Self, SILValue Src,
+                                   SILValue Initializer, SILValue Setter,
+                                   AssignOrInitInst::Mode Mode)
     : InstructionBase<SILInstructionKind::AssignOrInitInst,
                       NonValueInstruction>(Loc),
-      Operands(this, Self, Src, Initializer, Setter) {
+      Operands(this, Self, Src, Initializer, Setter), Property(P) {
   assert(Initializer->getType().is<SILFunctionType>());
   sharedUInt8().AssignOrInitInst.mode = uint8_t(Mode);
   Assignments.resize(getNumInitializedProperties());
@@ -1291,23 +1292,11 @@ bool AssignOrInitInst::isPropertyAlreadyInitialized(unsigned propertyIdx) {
 }
 
 StringRef AssignOrInitInst::getPropertyName() const {
-  auto *accessor = getReferencedInitAccessor();
-  assert(accessor);
-  return cast<VarDecl>(accessor->getStorage())->getNameStr();
+  return Property->getNameStr();
 }
 
 AccessorDecl *AssignOrInitInst::getReferencedInitAccessor() const {
-  SILValue initRef = getInitializer();
-  SILFunction *accessorFn = nullptr;
-
-  if (auto *PAI = dyn_cast<PartialApplyInst>(initRef)) {
-    accessorFn = PAI->getReferencedFunctionOrNull();
-  } else {
-    accessorFn = cast<FunctionRefInst>(initRef)->getReferencedFunctionOrNull();
-  }
-
-  assert(accessorFn);
-  return dyn_cast_or_null<AccessorDecl>(accessorFn->getDeclContext());
+  return Property->getOpaqueAccessor(AccessorKind::Init);
 }
 
 unsigned AssignOrInitInst::getNumInitializedProperties() const {

lib/SILGen/SILGenFunction.cpp

@@ -1859,6 +1859,7 @@ void SILGenFunction::emitAssignOrInit(SILLocation loc, ManagedValue selfValue,
     setterFRef = SILUndef::get(initFRef->getType(), F);
   }
 
-  B.createAssignOrInit(loc, selfValue.getValue(), newValue.forward(*this),
-                       initFRef, setterFRef, AssignOrInitInst::Unknown);
+  B.createAssignOrInit(loc, field, selfValue.getValue(),
+                       newValue.forward(*this), initFRef, setterFRef,
+                       AssignOrInitInst::Unknown);
 }