examples

Coverage Report

Created: 2025-05-23 02:48

/home/uke/oil/mycpp/gc_slab.h
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#ifndef GC_SLAB_H
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#define GC_SLAB_H
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#include <utility>  // std::is_pointer
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#include "mycpp/common.h"  // DISALLOW_COPY_AND_ASSIGN
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#include "mycpp/gc_obj.h"
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// Return the size of a resizeable allocation.  Just round up to the nearest
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// power of 2.  (CPython has an interesting policy in listobject.c.)
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//
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// https://stackoverflow.com/questions/466204/rounding-up-to-next-power-of-2
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//
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// Used by List<T> and Dict<K, V>.
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inline int RoundUp(int n) {
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  // TODO: what if int isn't 32 bits?
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  n--;
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  n |= n >> 1;
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  n |= n >> 2;
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  n |= n >> 4;
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  n |= n >> 8;
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  n |= n >> 16;
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  n++;
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  return n;
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}
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template <typename T>
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class Slab {
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  // Slabs of pointers are scanned; slabs of ints/bools are opaque.
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 public:
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  explicit Slab(unsigned num_items) {
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  }
_ZN4SlabIiEC2Ej
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  explicit Slab(unsigned num_items) {
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  }
_ZN4SlabIP6BigStrEC2Ej
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  explicit Slab(unsigned num_items) {
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  }
_ZN4SlabIP6Tuple2IP6BigStriEEC2Ej
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  explicit Slab(unsigned num_items) {
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  }
_ZN4SlabIP6Tuple2IiP6BigStrEEC2Ej
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  explicit Slab(unsigned num_items) {
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  }
_ZN4SlabIbEC2Ej
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  explicit Slab(unsigned num_items) {
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  }
_ZN4SlabIPN10hnode_asdl5FieldEEC2Ej
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  explicit Slab(unsigned num_items) {
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  }
Unexecuted instantiation: _ZN4SlabIPN10hnode_asdl7hnode_tEEC2Ej
_ZN4SlabIPN11pretty_asdl11MeasuredDocEEC2Ej
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  explicit Slab(unsigned num_items) {
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  }
_ZN4SlabIPN11pretty_asdl11DocFragmentEEC2Ej
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  explicit Slab(unsigned num_items) {
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  }
Unexecuted instantiation: _ZN4SlabIPN15test_classes_gc10OpaqueBaseEEC2Ej
Unexecuted instantiation: _ZN4SlabIPN15test_classes_gc12PointersBaseEEC2Ej
Unexecuted instantiation: _ZN4SlabIPN15test_classes_gc14BaseWithMethodEEC2Ej
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  static constexpr ObjHeader obj_header(unsigned num_items) {
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    return ObjHeader::Slab(
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        std::is_pointer<T>() ? HeapTag::Scanned : HeapTag::Opaque, num_items);
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  }
_ZN4SlabIiE10obj_headerEj
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  static constexpr ObjHeader obj_header(unsigned num_items) {
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    return ObjHeader::Slab(
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        std::is_pointer<T>() ? HeapTag::Scanned : HeapTag::Opaque, num_items);
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  }
_ZN4SlabIP6BigStrE10obj_headerEj
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  static constexpr ObjHeader obj_header(unsigned num_items) {
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    return ObjHeader::Slab(
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        std::is_pointer<T>() ? HeapTag::Scanned : HeapTag::Opaque, num_items);
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  }
_ZN4SlabIP6Tuple2IP6BigStriEE10obj_headerEj
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  static constexpr ObjHeader obj_header(unsigned num_items) {
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    return ObjHeader::Slab(
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        std::is_pointer<T>() ? HeapTag::Scanned : HeapTag::Opaque, num_items);
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  }
_ZN4SlabIP6Tuple2IiP6BigStrEE10obj_headerEj
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  static constexpr ObjHeader obj_header(unsigned num_items) {
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    return ObjHeader::Slab(
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        std::is_pointer<T>() ? HeapTag::Scanned : HeapTag::Opaque, num_items);
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  }
_ZN4SlabIbE10obj_headerEj
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  static constexpr ObjHeader obj_header(unsigned num_items) {
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    return ObjHeader::Slab(
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        std::is_pointer<T>() ? HeapTag::Scanned : HeapTag::Opaque, num_items);
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  }
_ZN4SlabIPN10hnode_asdl5FieldEE10obj_headerEj
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  static constexpr ObjHeader obj_header(unsigned num_items) {
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    return ObjHeader::Slab(
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        std::is_pointer<T>() ? HeapTag::Scanned : HeapTag::Opaque, num_items);
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  }
Unexecuted instantiation: _ZN4SlabIPN10hnode_asdl7hnode_tEE10obj_headerEj
_ZN4SlabIPN11pretty_asdl11MeasuredDocEE10obj_headerEj
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  static constexpr ObjHeader obj_header(unsigned num_items) {
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    return ObjHeader::Slab(
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        std::is_pointer<T>() ? HeapTag::Scanned : HeapTag::Opaque, num_items);
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  }
_ZN4SlabIPN11pretty_asdl11DocFragmentEE10obj_headerEj
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  static constexpr ObjHeader obj_header(unsigned num_items) {
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    return ObjHeader::Slab(
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        std::is_pointer<T>() ? HeapTag::Scanned : HeapTag::Opaque, num_items);
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  }
Unexecuted instantiation: _ZN4SlabIPN15test_classes_gc10OpaqueBaseEE10obj_headerEj
Unexecuted instantiation: _ZN4SlabIPN15test_classes_gc12PointersBaseEE10obj_headerEj
Unexecuted instantiation: _ZN4SlabIPN15test_classes_gc14BaseWithMethodEE10obj_headerEj
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  T items_[1];  // variable length
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  DISALLOW_COPY_AND_ASSIGN(Slab);
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};
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template <typename T, int N>
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class GlobalSlab {
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  // A template type with the same layout as Slab of length N.  For
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  // initializing global constant List.
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 public:
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  T items_[N];
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  DISALLOW_COPY_AND_ASSIGN(GlobalSlab)
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};
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// XXX(watk): Does this make sense?
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const int kSlabHeaderSize = sizeof(ObjHeader);
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#endif  // GC_SLAB_H