[IRGen] Remove recently-added uses of getHeapHeaderSize().

Author: Greg Parker

lib/IRGen/GenExistential.cpp

@@ -2318,7 +2318,7 @@ static llvm::Constant *getDeallocateBoxedOpaqueExistentialBufferFunction(
 
         //  Size = ((sizeof(HeapObject) + align) & ~align) + size
         auto *heapHeaderSize = llvm::ConstantInt::get(
-            IGF.IGM.SizeTy, getHeapHeaderSize(IGM).getValue());
+            IGF.IGM.SizeTy, IGM.RefCountedStructSize.getValue());
         size = Builder.CreateAdd(
             Builder.CreateAnd(Builder.CreateAdd(heapHeaderSize, alignmentMask),
                               Builder.CreateNot(alignmentMask)),
@@ -2412,7 +2412,7 @@ getProjectBoxedOpaqueExistentialFunction(IRGenFunction &IGF,
 
           //  StartOffset = ((sizeof(HeapObject) + align) & ~align)
           auto *heapHeaderSize = llvm::ConstantInt::get(
-              IGF.IGM.SizeTy, getHeapHeaderSize(IGM).getValue());
+              IGF.IGM.SizeTy, IGM.RefCountedStructSize.getValue());
           auto *startOffset = Builder.CreateAnd(
               Builder.CreateAdd(heapHeaderSize, alignmentMask),
               Builder.CreateNot(alignmentMask));

lib/IRGen/GenValueWitness.cpp

@@ -261,7 +261,8 @@ static Address emitDefaultProjectBuffer(IRGenFunction &IGF, Address buffer,
       auto *boxStart = IGF.Builder.CreateLoad(boxAddress);
       auto *alignmentMask = type.getAlignmentMask(IGF, T);
       auto *heapHeaderSize =
-          llvm::ConstantInt::get(IGM.SizeTy, getHeapHeaderSize(IGM).getValue());
+          llvm::ConstantInt::get(IGM.SizeTy,
+                                 IGM.RefCountedStructSize.getValue());
       auto *startOffset =
         Builder.CreateAnd(Builder.CreateAdd(heapHeaderSize, alignmentMask),
                               Builder.CreateNot(alignmentMask));
@@ -1112,7 +1113,7 @@ getCopyOutOfLineBoxPointerFunction(IRGenModule &IGM,
         IGF.Builder.CreateStore(ptr, dest);
         auto *alignmentMask = fixedTI.getStaticAlignmentMask(IGM);
         auto *heapHeaderSize = llvm::ConstantInt::get(
-            IGM.SizeTy, getHeapHeaderSize(IGM).getValue());
+            IGM.SizeTy, IGM.RefCountedStructSize.getValue());
         auto *startOffset = IGF.Builder.CreateAnd(
             IGF.Builder.CreateAdd(heapHeaderSize, alignmentMask),
             IGF.Builder.CreateNot(alignmentMask));

lib/IRGen/StructLayout.h

@@ -385,8 +385,6 @@ class StructLayout {
                      const llvm::Twine &name = "") const;
 };
 
-Size getHeapHeaderSize(IRGenModule &IGM);
-
 /// Different policies for accessing a physical field.
 enum class FieldAccess : uint8_t {
   /// Instance variable offsets are constant.