factor/vm/layouts.hpp

354 lines
8.4 KiB
C++

namespace factor {
typedef intptr_t fixnum;
typedef uintptr_t cell;
inline static cell align(cell a, cell b) { return (a + (b - 1)) & ~(b - 1); }
inline static cell alignment_for(cell a, cell b) { return align(a, b) - a; }
static const cell data_alignment = 16;
// Must match leaf-stack-frame-size in core/layouts/layouts.factor
#define LEAF_FRAME_SIZE 16
#define WORD_SIZE (signed)(sizeof(cell) * 8)
#define TAG_MASK 15
#define TAG_BITS 4
#define TAG(x) ((cell)(x) & TAG_MASK)
#define UNTAG(x) ((cell)(x) & ~TAG_MASK)
#define RETAG(x, tag) (UNTAG(x) | (tag))
// Type tags, should be kept in sync with:
// core/bootstrap/layouts/layouts.factor
#define FIXNUM_TYPE 0
#define F_TYPE 1
#define ARRAY_TYPE 2
#define FLOAT_TYPE 3
#define QUOTATION_TYPE 4
#define BIGNUM_TYPE 5
#define ALIEN_TYPE 6
#define TUPLE_TYPE 7
#define WRAPPER_TYPE 8
#define BYTE_ARRAY_TYPE 9
#define CALLSTACK_TYPE 10
#define STRING_TYPE 11
#define WORD_TYPE 12
#define DLL_TYPE 13
#define TYPE_COUNT 14
static inline const char* type_name(cell type) {
switch (type) {
case FIXNUM_TYPE:
return "fixnum";
case F_TYPE:
return "f";
case ARRAY_TYPE:
return "array";
case FLOAT_TYPE:
return "float";
case QUOTATION_TYPE:
return "quotation";
case BIGNUM_TYPE:
return "bignum";
case ALIEN_TYPE:
return "alien";
case TUPLE_TYPE:
return "tuple";
case WRAPPER_TYPE:
return "wrapper";
case BYTE_ARRAY_TYPE:
return "byte-array";
case CALLSTACK_TYPE:
return "callstack";
case STRING_TYPE:
return "string";
case WORD_TYPE:
return "word";
case DLL_TYPE:
return "dll";
default:
FACTOR_ASSERT(false);
return "";
}
}
enum code_block_type {
CODE_BLOCK_UNOPTIMIZED,
CODE_BLOCK_OPTIMIZED,
CODE_BLOCK_PIC
};
// Constants used when floating-point trap exceptions are thrown
enum {
FP_TRAP_INVALID_OPERATION = 1 << 0,
FP_TRAP_OVERFLOW = 1 << 1,
FP_TRAP_UNDERFLOW = 1 << 2,
FP_TRAP_ZERO_DIVIDE = 1 << 3,
FP_TRAP_INEXACT = 1 << 4,
};
// What Factor calls 'f'
static const cell false_object = F_TYPE;
inline static bool immediate_p(cell obj) {
// We assume that fixnums have tag 0 and false_object has tag 1
return TAG(obj) <= F_TYPE;
}
inline static fixnum untag_fixnum(cell tagged) {
FACTOR_ASSERT(TAG(tagged) == FIXNUM_TYPE);
return ((fixnum)tagged) >> TAG_BITS;
}
inline static cell tag_fixnum(fixnum untagged) {
return (untagged << TAG_BITS) | FIXNUM_TYPE;
}
#define NO_TYPE_CHECK static const cell type_number = TYPE_COUNT
struct object {
NO_TYPE_CHECK;
// header format (bits indexed with least significant as zero):
// bit 0 : free?
// bit 1 : forwarding pointer?
// if not forwarding:
// bit 2-5 : tag
// bit 7-end : hashcode
// if forwarding:
// bit 2-end : forwarding pointer
cell header;
template <typename Fixup> cell base_size(Fixup fixup) const;
template <typename Fixup> cell size(Fixup fixup) const;
cell size() const;
cell slot_count() const;
template <typename Fixup> cell slot_count(Fixup fixup) const;
cell* slots() const { return (cell*)this; }
template <typename Iterator> void each_slot(Iterator& iter);
// Only valid for objects in tenured space; must cast to free_heap_block
// to do anything with it if its free
bool free_p() const { return (header & 1) == 1; }
cell type() const { return (header >> 2) & TAG_MASK; }
void initialize(cell type) { header = type << 2; }
cell hashcode() const { return (header >> 6); }
void set_hashcode(cell hashcode) {
header = (header & 0x3f) | (hashcode << 6);
}
bool forwarding_pointer_p() const { return (header & 2) == 2; }
object* forwarding_pointer() const { return (object*)UNTAG(header); }
void forward_to(object* pointer) { header = ((cell)pointer | 2); }
};
// Assembly code makes assumptions about the layout of this struct
struct array : public object {
static const cell type_number = ARRAY_TYPE;
static const cell element_size = sizeof(cell);
// tagged
cell capacity;
cell* data() const { return (cell*)(this + 1); }
};
// These are really just arrays, but certain elements have special
// significance
struct tuple_layout : public array {
NO_TYPE_CHECK;
// tagged
cell klass;
// tagged fixnum
cell size;
// tagged fixnum
cell echelon;
};
struct bignum : public object {
static const cell type_number = BIGNUM_TYPE;
static const cell element_size = sizeof(cell);
// tagged
cell capacity;
cell* data() const { return (cell*)(this + 1); }
};
struct byte_array : public object {
static const cell type_number = BYTE_ARRAY_TYPE;
static const cell element_size = 1;
// tagged
cell capacity;
#ifndef FACTOR_64
cell padding0;
cell padding1;
#endif
template <typename Scalar> Scalar* data() const {
return (Scalar*)(this + 1);
}
};
// Assembly code makes assumptions about the layout of this struct
struct string : public object {
static const cell type_number = STRING_TYPE;
// tagged num of chars
cell length;
// tagged
cell aux;
// tagged
cell hashcode;
uint8_t* data() const { return (uint8_t*)(this + 1); }
};
struct code_block;
// Assembly code makes assumptions about the layout of this struct:
// basis/bootstrap/images/images.factor
// basis/compiler/constants/constants.factor
// core/bootstrap/primitives.factor
struct word : public object {
static const cell type_number = WORD_TYPE;
// TAGGED hashcode
cell hashcode;
// TAGGED word name
cell name;
// TAGGED word vocabulary
cell vocabulary;
// TAGGED definition
cell def;
// TAGGED property assoc for library code
cell props;
// TAGGED alternative entry point for direct non-tail calls. Used for inline
// caching
cell pic_def;
// TAGGED alternative entry point for direct tail calls. Used for inline
// caching
cell pic_tail_def;
// TAGGED machine code for sub-primitive
cell subprimitive;
// UNTAGGED entry point: jump here to execute word
cell entry_point;
// UNTAGGED compiled code block
// defined in code_blocks.hpp
code_block* code() const;
};
// Assembly code makes assumptions about the layout of this struct
struct wrapper : public object {
static const cell type_number = WRAPPER_TYPE;
cell object;
};
// Assembly code makes assumptions about the layout of this struct
struct boxed_float : object {
static const cell type_number = FLOAT_TYPE;
#ifndef FACTOR_64
cell padding;
#endif
double n;
};
// Assembly code makes assumptions about the layout of this struct:
// basis/bootstrap/images/images.factor
// basis/compiler/constants/constants.factor
// core/bootstrap/primitives.factor
struct quotation : public object {
static const cell type_number = QUOTATION_TYPE;
// tagged
cell array;
// tagged
cell cached_effect;
// tagged
cell cache_counter;
// UNTAGGED entry point; jump here to call quotation
cell entry_point;
// defined in code_blocks.hpp
code_block* code() const;
};
// Assembly code makes assumptions about the layout of this struct
struct alien : public object {
static const cell type_number = ALIEN_TYPE;
// tagged
cell base;
// tagged
cell expired;
// untagged
cell displacement;
// untagged
cell address;
void update_address() {
if (base == false_object)
address = displacement;
else
address = UNTAG(base) + sizeof(byte_array) + displacement;
}
};
struct dll : public object {
static const cell type_number = DLL_TYPE;
// tagged byte array holding a C string
cell path;
// OS-specific handle
void* handle;
};
struct callstack : public object {
static const cell type_number = CALLSTACK_TYPE;
// tagged
cell length;
cell frame_top_at(cell offset) const {
return (cell)(this + 1) + offset;
}
void* top() const { return (void*)(this + 1); }
void* bottom() const {
return (void*)((cell)(this + 1) + untag_fixnum(length));
}
};
struct tuple : public object {
static const cell type_number = TUPLE_TYPE;
// tagged layout
cell layout;
cell* data() const { return (cell*)(this + 1); }
};
inline static cell tuple_capacity(const tuple_layout *layout) {
return untag_fixnum(layout->size);
}
inline static cell tuple_size(const tuple_layout* layout) {
return sizeof(tuple) + tuple_capacity(layout) * sizeof(cell);
}
inline static cell string_capacity(const string* str) {
return untag_fixnum(str->length);
}
inline static cell string_size(cell size) { return sizeof(string) + size; }
}