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++ #include <assert.h>
++ #include <limits.h>
++ #include <stddef.h>
++ #include <stdio.h>
++ #include <stdlib.h>
++ #include <string.h>
++
++ #include "tlsf.h"
++
++ QT_BEGIN_NAMESPACE
++
++ namespace QtPrivate {
++
++ #if defined(__cplusplus)
++ #define tlsf_decl inline
++ #else
++ #define tlsf_decl static
++ #endif
++
++ /*
++ ** Architecture-specific bit manipulation routines.
++ **
++ ** TLSF achieves O(1) cost for malloc and free operations by limiting
++ ** the search for a free block to a free list of guaranteed size
++ ** adequate to fulfill the request, combined with efficient free list
++ ** queries using bitmasks and architecture-specific bit-manipulation
++ ** routines.
++ **
++ ** Most modern processors provide instructions to count leading zeroes
++ ** in a word, find the lowest and highest set bit, etc. These
++ ** specific implementations will be used when available, falling back
++ ** to a reasonably efficient generic implementation.
++ **
++ ** NOTE: TLSF spec relies on ffs/fls returning value 0..31.
++ ** ffs/fls return 1-32 by default, returning 0 for error.
++ */
++
++ /*
++ ** Detect whether or not we are building for a 32- or 64-bit (LP/LLP)
++ ** architecture. There is no reliable portable method at compile-time.
++ */
++ #if defined (__alpha__) || defined (__ia64__) || defined (__x86_64__) \
++ || defined (_WIN64) || defined (__LP64__) || defined (__LLP64__)
++ #define TLSF_64BIT
++ #endif
++
++ /*
++ ** gcc 3.4 and above have builtin support, specialized for architecture.
++ ** Some compilers masquerade as gcc; patchlevel test filters them out.
++ */
++ #if defined (__GNUC__) && (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)) \
++ && defined (__GNUC_PATCHLEVEL__)
++
++ #if defined (__SNC__)
++ /* SNC for Playstation 3. */
++
++ tlsf_decl int tlsf_ffs(unsigned int word)
++ {
++ const unsigned int reverse = word & (~word + 1);
++ const int bit = 32 - __builtin_clz(reverse);
++ return bit - 1;
++ }
++
++ #else
++
++ tlsf_decl int tlsf_ffs(unsigned int word)
++ {
++ return __builtin_ffs(word) - 1;
++ }
++
++ #endif
++
++ tlsf_decl int tlsf_fls(unsigned int word)
++ {
++ const int bit = word ? 32 - __builtin_clz(word) : 0;
++ return bit - 1;
++ }
++
++ #elif defined (_MSC_VER) && (_MSC_VER >= 1400) && (defined (_M_IX86) || defined (_M_X64))
++ /* Microsoft Visual C++ support on x86/X64 architectures. */
++
++ #include <intrin.h>
++
++ #pragma intrinsic(_BitScanReverse)
++ #pragma intrinsic(_BitScanForward)
++
++ tlsf_decl int tlsf_fls(unsigned int word)
++ {
++ unsigned long index;
++ return _BitScanReverse(&index, word) ? index : -1;
++ }
++
++ tlsf_decl int tlsf_ffs(unsigned int word)
++ {
++ unsigned long index;
++ return _BitScanForward(&index, word) ? index : -1;
++ }
++
++ #elif defined (_MSC_VER) && defined (_M_PPC)
++ /* Microsoft Visual C++ support on PowerPC architectures. */
++
++ #include <ppcintrinsics.h>
++
++ tlsf_decl int tlsf_fls(unsigned int word)
++ {
++ const int bit = 32 - _CountLeadingZeros(word);
++ return bit - 1;
++ }
++
++ tlsf_decl int tlsf_ffs(unsigned int word)
++ {
++ const unsigned int reverse = word & (~word + 1);
++ const int bit = 32 - _CountLeadingZeros(reverse);
++ return bit - 1;
++ }
++
++ #elif defined (__ARMCC_VERSION)
++ /* RealView Compilation Tools for ARM */
++
++ tlsf_decl int tlsf_ffs(unsigned int word)
++ {
++ const unsigned int reverse = word & (~word + 1);
++ const int bit = 32 - __clz(reverse);
++ return bit - 1;
++ }
++
++ tlsf_decl int tlsf_fls(unsigned int word)
++ {
++ const int bit = word ? 32 - __clz(word) : 0;
++ return bit - 1;
++ }
++
++ #elif defined (__ghs__)
++ /* Green Hills support for PowerPC */
++
++ #include <ppc_ghs.h>
++
++ tlsf_decl int tlsf_ffs(unsigned int word)
++ {
++ const unsigned int reverse = word & (~word + 1);
++ const int bit = 32 - __CLZ32(reverse);
++ return bit - 1;
++ }
++
++ tlsf_decl int tlsf_fls(unsigned int word)
++ {
++ const int bit = word ? 32 - __CLZ32(word) : 0;
++ return bit - 1;
++ }
++
++ #else
++ /* Fall back to generic implementation. */
++
++ tlsf_decl int tlsf_fls_generic(unsigned int word)
++ {
++ int bit = 32;
++
++ if (!word) bit -= 1;
++ if (!(word & 0xffff0000)) { word <<= 16; bit -= 16; }
++ if (!(word & 0xff000000)) { word <<= 8; bit -= 8; }
++ if (!(word & 0xf0000000)) { word <<= 4; bit -= 4; }
++ if (!(word & 0xc0000000)) { word <<= 2; bit -= 2; }
++ if (!(word & 0x80000000)) { word <<= 1; bit -= 1; }
++
++ return bit;
++ }
++
++ /* Implement ffs in terms of fls. */
++ tlsf_decl int tlsf_ffs(unsigned int word)
++ {
++ return tlsf_fls_generic(word & (~word + 1)) - 1;
++ }
++
++ tlsf_decl int tlsf_fls(unsigned int word)
++ {
++ return tlsf_fls_generic(word) - 1;
++ }
++
++ #endif
++
++ /* Possibly 64-bit version of tlsf_fls. */
++ #if defined (TLSF_64BIT)
++ tlsf_decl int tlsf_fls_sizet(size_t size)
++ {
++ int high = (int)(size >> 32);
++ int bits = 0;
++ if (high)
++ {
++ bits = 32 + tlsf_fls(high);
++ }
++ else
++ {
++ bits = tlsf_fls((int)size & 0xffffffff);
++
++ }
++ return bits;
++ }
++ #else
++ #define tlsf_fls_sizet tlsf_fls
++ #endif
++
++ #undef tlsf_decl
++
++ /*
++ ** Constants.
++ */
++
++ /* Public constants: may be modified. */
++ enum tlsf_public
++ {
++ /* log2 of number of linear subdivisions of block sizes. Larger
++ ** values require more memory in the control structure. Values of
++ ** 4 or 5 are typical.
++ */
++ SL_INDEX_COUNT_LOG2 = 5,
++ };
++
++ /* Private constants: do not modify. */
++ enum tlsf_private
++ {
++ #if defined (TLSF_64BIT)
++ /* All allocation sizes and addresses are aligned to 8 bytes. */
++ ALIGN_SIZE_LOG2 = 3,
++ #else
++ /* All allocation sizes and addresses are aligned to 4 bytes. */
++ ALIGN_SIZE_LOG2 = 2,
++ #endif
++ ALIGN_SIZE = (1 << ALIGN_SIZE_LOG2),
++
++ /*
++ ** We support allocations of sizes up to (1 << FL_INDEX_MAX) bits.
++ ** However, because we linearly subdivide the second-level lists, and
++ ** our minimum size granularity is 4 bytes, it doesn't make sense to
++ ** create first-level lists for sizes smaller than SL_INDEX_COUNT * 4,
++ ** or (1 << (SL_INDEX_COUNT_LOG2 + 2)) bytes, as there we will be
++ ** trying to split size ranges into more slots than we have available.
++ ** Instead, we calculate the minimum threshold size, and place all
++ ** blocks below that size into the 0th first-level list.
++ */
++
++ #if defined (TLSF_64BIT)
++ /*
++ ** TODO: We can increase this to support larger sizes, at the expense
++ ** of more overhead in the TLSF structure.
++ */
++ FL_INDEX_MAX = 32,
++ #else
++ FL_INDEX_MAX = 30,
++ #endif
++ SL_INDEX_COUNT = (1 << SL_INDEX_COUNT_LOG2),
++ FL_INDEX_SHIFT = (SL_INDEX_COUNT_LOG2 + ALIGN_SIZE_LOG2),
++ FL_INDEX_COUNT = (FL_INDEX_MAX - FL_INDEX_SHIFT + 1),
++
++ SMALL_BLOCK_SIZE = (1 << FL_INDEX_SHIFT),
++ };
++
++ /*
++ ** Cast and min/max macros.
++ */
++
++ #define tlsf_cast(t, exp) ((t) (exp))
++ #define tlsf_min(a, b) ((a) < (b) ? (a) : (b))
++ #define tlsf_max(a, b) ((a) > (b) ? (a) : (b))
++
++ /*
++ ** Set assert macro, if it has not been provided by the user.
++ */
++ #if !defined (tlsf_assert)
++ #define tlsf_assert assert
++ #endif
++
++ /*
++ ** Static assertion mechanism.
++ */
++
++ #define _tlsf_glue2(x, y) x ## y
++ #define _tlsf_glue(x, y) _tlsf_glue2(x, y)
++ #define tlsf_static_assert(exp) \
++ typedef char _tlsf_glue(static_assert, __LINE__) [(exp) ? 1 : -1]
++
++ /* This code has been tested on 32- and 64-bit (LP/LLP) architectures. */
++ tlsf_static_assert(sizeof(int) * CHAR_BIT == 32);
++ tlsf_static_assert(sizeof(size_t) * CHAR_BIT >= 32);
++ tlsf_static_assert(sizeof(size_t) * CHAR_BIT <= 64);
++
++ /* SL_INDEX_COUNT must be <= number of bits in sl_bitmap's storage type. */
++ tlsf_static_assert(sizeof(unsigned int) * CHAR_BIT >= SL_INDEX_COUNT);
++
++ /* Ensure we've properly tuned our sizes. */
++ tlsf_static_assert(ALIGN_SIZE == SMALL_BLOCK_SIZE / SL_INDEX_COUNT);
++
++ /*
++ ** Data structures and associated constants.
++ */
++
++ /*
++ ** Block header structure.
++ **
++ ** There are several implementation subtleties involved:
++ ** - The prev_phys_block field is only valid if the previous block is free.
++ ** - The prev_phys_block field is actually stored at the end of the
++ ** previous block. It appears at the beginning of this structure only to
++ ** simplify the implementation.
++ ** - The next_free / prev_free fields are only valid if the block is free.
++ */
++ typedef struct block_header_t
++ {
++ /* Points to the previous physical block. */
++ struct block_header_t* prev_phys_block;
++
++ /* The size of this block, excluding the block header. */
++ size_t size;
++
++ /* Next and previous free blocks. */
++ struct block_header_t* next_free;
++ struct block_header_t* prev_free;
++ } block_header_t;
++
++ /*
++ ** Since block sizes are always at least a multiple of 4, the two least
++ ** significant bits of the size field are used to store the block status:
++ ** - bit 0: whether block is busy or free
++ ** - bit 1: whether previous block is busy or free
++ */
++ static const size_t block_header_free_bit = 1 << 0;
++ static const size_t block_header_prev_free_bit = 1 << 1;
++
++ /*
++ ** The size of the block header exposed to used blocks is the size field.
++ ** The prev_phys_block field is stored *inside* the previous free block.
++ */
++ static const size_t block_header_overhead = sizeof(size_t);
++
++ /* User data starts directly after the size field in a used block. */
++ static const size_t block_start_offset =
++ offsetof(block_header_t, size) + sizeof(size_t);
++
++ /*
++ ** A free block must be large enough to store its header minus the size of
++ ** the prev_phys_block field, and no larger than the number of addressable
++ ** bits for FL_INDEX.
++ */
++ static const size_t block_size_min =
++ sizeof(block_header_t) - sizeof(block_header_t*);
++ static const size_t block_size_max = tlsf_cast(size_t, 1) << FL_INDEX_MAX;
++
++
++ /* The TLSF control structure. */
++ typedef struct control_t
++ {
++ /* Empty lists point at this block to indicate they are free. */
++ block_header_t block_null;
++
++ /* Bitmaps for free lists. */
++ unsigned int fl_bitmap;
++ unsigned int sl_bitmap[FL_INDEX_COUNT];
++
++ /* Head of free lists. */
++ block_header_t* blocks[FL_INDEX_COUNT][SL_INDEX_COUNT];
++ } control_t;
++
++ /* A type used for casting when doing pointer arithmetic. */
++ typedef ptrdiff_t tlsfptr_t;
++
++ /*
++ ** block_header_t member functions.
++ */
++
++ static size_t block_size(const block_header_t* block)
++ {
++ return block->size & ~(block_header_free_bit | block_header_prev_free_bit);
++ }
++
++ static void block_set_size(block_header_t* block, size_t size)
++ {
++ const size_t oldsize = block->size;
++ block->size = size | (oldsize & (block_header_free_bit | block_header_prev_free_bit));
++ }
++
++ static int block_is_last(const block_header_t* block)
++ {
++ return block_size(block) == 0;
++ }
++
++ static int block_is_free(const block_header_t* block)
++ {
++ return tlsf_cast(int, block->size & block_header_free_bit);
++ }
++
++ static void block_set_free(block_header_t* block)
++ {
++ block->size |= block_header_free_bit;
++ }
++
++ static void block_set_used(block_header_t* block)
++ {
++ block->size &= ~block_header_free_bit;
++ }
++
++ static int block_is_prev_free(const block_header_t* block)
++ {
++ return tlsf_cast(int, block->size & block_header_prev_free_bit);
++ }
++
++ static void block_set_prev_free(block_header_t* block)
++ {
++ block->size |= block_header_prev_free_bit;
++ }
++
++ static void block_set_prev_used(block_header_t* block)
++ {
++ block->size &= ~block_header_prev_free_bit;
++ }
++
++ static block_header_t* block_from_ptr(const void* ptr)
++ {
++ return tlsf_cast(block_header_t*,
++ tlsf_cast(unsigned char*, ptr) - block_start_offset);
++ }
++
++ static void* block_to_ptr(const block_header_t* block)
++ {
++ return tlsf_cast(void*,
++ tlsf_cast(unsigned char*, block) + block_start_offset);
++ }
++
++ /* Return location of next block after block of given size. */
++ static block_header_t* offset_to_block(const void* ptr, size_t size)
++ {
++ return tlsf_cast(block_header_t*, tlsf_cast(tlsfptr_t, ptr) + size);
++ }
++
++ /* Return location of previous block. */
++ static block_header_t* block_prev(const block_header_t* block)
++ {
++ tlsf_assert(block_is_prev_free(block) && "previous block must be free");
++ return block->prev_phys_block;
++ }
++
++ /* Return location of next existing block. */
++ static block_header_t* block_next(const block_header_t* block)
++ {
++ block_header_t* next = offset_to_block(block_to_ptr(block),
++ block_size(block) - block_header_overhead);
++ tlsf_assert(!block_is_last(block));
++ return next;
++ }
++
++ /* Link a new block with its physical neighbor, return the neighbor. */
++ static block_header_t* block_link_next(block_header_t* block)
++ {
++ block_header_t* next = block_next(block);
++ next->prev_phys_block = block;
++ return next;
++ }
++
++ static void block_mark_as_free(block_header_t* block)
++ {
++ /* Link the block to the next block, first. */
++ block_header_t* next = block_link_next(block);
++ block_set_prev_free(next);
++ block_set_free(block);
++ }
++
++ static void block_mark_as_used(block_header_t* block)
++ {
++ block_header_t* next = block_next(block);
++ block_set_prev_used(next);
++ block_set_used(block);
++ }
++
++ static size_t align_up(size_t x, size_t align)
++ {
++ tlsf_assert(0 == (align & (align - 1)) && "must align to a power of two");
++ return (x + (align - 1)) & ~(align - 1);
++ }
++
++ static size_t align_down(size_t x, size_t align)
++ {
++ tlsf_assert(0 == (align & (align - 1)) && "must align to a power of two");
++ return x - (x & (align - 1));
++ }
++
++ static void* align_ptr(const void* ptr, size_t align)
++ {
++ const tlsfptr_t aligned =
++ (tlsf_cast(tlsfptr_t, ptr) + (align - 1)) & ~(align - 1);
++ tlsf_assert(0 == (align & (align - 1)) && "must align to a power of two");
++ return tlsf_cast(void*, aligned);
++ }
++
++ /*
++ ** Adjust an allocation size to be aligned to word size, and no smaller
++ ** than internal minimum.
++ */
++ static size_t adjust_request_size(size_t size, size_t align)
++ {
++ size_t adjust = 0;
++ if (size)
++ {
++ const size_t aligned = align_up(size, align);
++
++ /* aligned sized must not exceed block_size_max or we'll go out of bounds on sl_bitmap */
++ if (aligned < block_size_max)
++ {
++ adjust = tlsf_max(aligned, block_size_min);
++ }
++ }
++ return adjust;
++ }
++
++ /*
++ ** TLSF utility functions. In most cases, these are direct translations of
++ ** the documentation found in the white paper.
++ */
++
++ static void mapping_insert(size_t size, int* fli, int* sli)
++ {
++ int fl, sl;
++ if (size < SMALL_BLOCK_SIZE)
++ {
++ /* Store small blocks in first list. */
++ fl = 0;
++ sl = tlsf_cast(int, size) / (SMALL_BLOCK_SIZE / SL_INDEX_COUNT);
++ }
++ else
++ {
++ fl = tlsf_fls_sizet(size);
++ sl = tlsf_cast(int, size >> (fl - SL_INDEX_COUNT_LOG2)) ^ (1 << SL_INDEX_COUNT_LOG2);
++ fl -= (FL_INDEX_SHIFT - 1);
++ }
++ *fli = fl;
++ *sli = sl;
++ }
++
++ /* This version rounds up to the next block size (for allocations) */
++ static void mapping_search(size_t size, int* fli, int* sli)
++ {
++ if (size >= SMALL_BLOCK_SIZE)
++ {
++ const size_t round = (1 << (tlsf_fls_sizet(size) - SL_INDEX_COUNT_LOG2)) - 1;
++ size += round;
++ }
++ mapping_insert(size, fli, sli);
++ }
++
++ static block_header_t* search_suitable_block(control_t* control, int* fli, int* sli)
++ {
++ int fl = *fli;
++ int sl = *sli;
++
++ /*
++ ** First, search for a block in the list associated with the given
++ ** fl/sl index.
++ */
++ unsigned int sl_map = control->sl_bitmap[fl] & (~0U << sl);
++ if (!sl_map)
++ {
++ /* No block exists. Search in the next largest first-level list. */
++ const unsigned int fl_map = control->fl_bitmap & (~0U << (fl + 1));
++ if (!fl_map)
++ {
++ /* No free blocks available, memory has been exhausted. */
++ return 0;
++ }
++
++ fl = tlsf_ffs(fl_map);
++ *fli = fl;
++ sl_map = control->sl_bitmap[fl];
++ }
++ tlsf_assert(sl_map && "internal error - second level bitmap is null");
++ sl = tlsf_ffs(sl_map);
++ *sli = sl;
++
++ /* Return the first block in the free list. */
++ return control->blocks[fl][sl];
++ }
++
++ /* Remove a free block from the free list.*/
++ static void remove_free_block(control_t* control, block_header_t* block, int fl, int sl)
++ {
++ block_header_t* prev = block->prev_free;
++ block_header_t* next = block->next_free;
++ tlsf_assert(prev && "prev_free field can not be null");
++ tlsf_assert(next && "next_free field can not be null");
++ next->prev_free = prev;
++ prev->next_free = next;
++
++ /* If this block is the head of the free list, set new head. */
++ if (control->blocks[fl][sl] == block)
++ {
++ control->blocks[fl][sl] = next;
++
++ /* If the new head is null, clear the bitmap. */
++ if (next == &control->block_null)
++ {
++ control->sl_bitmap[fl] &= ~(1U << sl);
++
++ /* If the second bitmap is now empty, clear the fl bitmap. */
++ if (!control->sl_bitmap[fl])
++ {
++ control->fl_bitmap &= ~(1U << fl);
++ }
++ }
++ }
++ }
++
++ /* Insert a free block into the free block list. */
++ static void insert_free_block(control_t* control, block_header_t* block, int fl, int sl)
++ {
++ block_header_t* current = control->blocks[fl][sl];
++ tlsf_assert(current && "free list cannot have a null entry");
++ tlsf_assert(block && "cannot insert a null entry into the free list");
++ block->next_free = current;
++ block->prev_free = &control->block_null;
++ current->prev_free = block;
++
++ tlsf_assert(block_to_ptr(block) == align_ptr(block_to_ptr(block), ALIGN_SIZE)
++ && "block not aligned properly");
++ /*
++ ** Insert the new block at the head of the list, and mark the first-
++ ** and second-level bitmaps appropriately.
++ */
++ control->blocks[fl][sl] = block;
++ control->fl_bitmap |= (1U << fl);
++ control->sl_bitmap[fl] |= (1U << sl);
++ }
++
++ /* Remove a given block from the free list. */
++ static void block_remove(control_t* control, block_header_t* block)
++ {
++ int fl, sl;
++ mapping_insert(block_size(block), &fl, &sl);
++ remove_free_block(control, block, fl, sl);
++ }
++
++ /* Insert a given block into the free list. */
++ static void block_insert(control_t* control, block_header_t* block)
++ {
++ int fl, sl;
++ mapping_insert(block_size(block), &fl, &sl);
++ insert_free_block(control, block, fl, sl);
++ }
++
++ static int block_can_split(block_header_t* block, size_t size)
++ {
++ return block_size(block) >= sizeof(block_header_t) + size;
++ }
++
++ /* Split a block into two, the second of which is free. */
++ static block_header_t* block_split(block_header_t* block, size_t size)
++ {
++ /* Calculate the amount of space left in the remaining block. */
++ block_header_t* remaining =
++ offset_to_block(block_to_ptr(block), size - block_header_overhead);
++
++ const size_t remain_size = block_size(block) - (size + block_header_overhead);
++
++ tlsf_assert(block_to_ptr(remaining) == align_ptr(block_to_ptr(remaining), ALIGN_SIZE)
++ && "remaining block not aligned properly");
++
++ tlsf_assert(block_size(block) == remain_size + size + block_header_overhead);
++ block_set_size(remaining, remain_size);
++ tlsf_assert(block_size(remaining) >= block_size_min && "block split with invalid size");
++
++ block_set_size(block, size);
++ block_mark_as_free(remaining);
++
++ return remaining;
++ }
++
++ /* Absorb a free block's storage into an adjacent previous free block. */
++ static block_header_t* block_absorb(block_header_t* prev, block_header_t* block)
++ {
++ tlsf_assert(!block_is_last(prev) && "previous block can't be last");
++ /* Note: Leaves flags untouched. */
++ prev->size += block_size(block) + block_header_overhead;
++ block_link_next(prev);
++ return prev;
++ }
++
++ /* Merge a just-freed block with an adjacent previous free block. */
++ static block_header_t* block_merge_prev(control_t* control, block_header_t* block)
++ {
++ if (block_is_prev_free(block))
++ {
++ block_header_t* prev = block_prev(block);
++ tlsf_assert(prev && "prev physical block can't be null");
++ tlsf_assert(block_is_free(prev) && "prev block is not free though marked as such");
++ block_remove(control, prev);
++ block = block_absorb(prev, block);
++ }
++
++ return block;
++ }
++
++ /* Merge a just-freed block with an adjacent free block. */
++ static block_header_t* block_merge_next(control_t* control, block_header_t* block)
++ {
++ block_header_t* next = block_next(block);
++ tlsf_assert(next && "next physical block can't be null");
++
++ if (block_is_free(next))
++ {
++ tlsf_assert(!block_is_last(block) && "previous block can't be last");
++ block_remove(control, next);
++ block = block_absorb(block, next);
++ }
++
++ return block;
++ }
++
++ /* Trim any trailing block space off the end of a block, return to pool. */
++ static void block_trim_free(control_t* control, block_header_t* block, size_t size)
++ {
++ tlsf_assert(block_is_free(block) && "block must be free");
++ if (block_can_split(block, size))
++ {
++ block_header_t* remaining_block = block_split(block, size);
++ block_link_next(block);
++ block_set_prev_free(remaining_block);
++ block_insert(control, remaining_block);
++ }
++ }
++
++ /* Trim any trailing block space off the end of a used block, return to pool. */
++ static void block_trim_used(control_t* control, block_header_t* block, size_t size)
++ {
++ tlsf_assert(!block_is_free(block) && "block must be used");
++ if (block_can_split(block, size))
++ {
++ /* If the next block is free, we must coalesce. */
++ block_header_t* remaining_block = block_split(block, size);
++ block_set_prev_used(remaining_block);
++
++ remaining_block = block_merge_next(control, remaining_block);
++ block_insert(control, remaining_block);
++ }
++ }
++
++ static block_header_t* block_trim_free_leading(control_t* control, block_header_t* block, size_t size)
++ {
++ block_header_t* remaining_block = block;
++ if (block_can_split(block, size))
++ {
++ /* We want the 2nd block. */
++ remaining_block = block_split(block, size - block_header_overhead);
++ block_set_prev_free(remaining_block);
++
++ block_link_next(block);
++ block_insert(control, block);
++ }
++
++ return remaining_block;
++ }
++
++ static block_header_t* block_locate_free(control_t* control, size_t size)
++ {
++ int fl = 0, sl = 0;
++ block_header_t* block = 0;
++
++ if (size)
++ {
++ mapping_search(size, &fl, &sl);
++
++ /*
++ ** mapping_search can futz with the size, so for excessively large sizes it can sometimes wind up
++ ** with indices that are off the end of the block array.
++ ** So, we protect against that here, since this is the only callsite of mapping_search.
++ ** Note that we don't need to check sl, since it comes from a modulo operation that guarantees it's always in range.
++ */
++ if (fl < FL_INDEX_COUNT)
++ {
++ block = search_suitable_block(control, &fl, &sl);
++ }
++ }
++
++ if (block)
++ {
++ tlsf_assert(block_size(block) >= size);
++ remove_free_block(control, block, fl, sl);
++ }
++
++ return block;
++ }
++
++ static void* block_prepare_used(control_t* control, block_header_t* block, size_t size)
++ {
++ void* p = 0;
++ if (block)
++ {
++ tlsf_assert(size && "size must be non-zero");
++ block_trim_free(control, block, size);
++ block_mark_as_used(block);
++ p = block_to_ptr(block);
++ }
++ return p;
++ }
++
++ /* Clear structure and point all empty lists at the null block. */
++ static void control_construct(control_t* control)
++ {
++ int i, j;
++
++ control->block_null.next_free = &control->block_null;
++ control->block_null.prev_free = &control->block_null;
++
++ control->fl_bitmap = 0;
++ for (i = 0; i < FL_INDEX_COUNT; ++i)
++ {
++ control->sl_bitmap[i] = 0;
++ for (j = 0; j < SL_INDEX_COUNT; ++j)
++ {
++ control->blocks[i][j] = &control->block_null;
++ }
++ }
++ }
++
++ /*
++ ** Debugging utilities.
++ */
++
++ typedef struct integrity_t
++ {
++ int prev_status;
++ int status;
++ } integrity_t;
++
++ #define tlsf_insist(x) { tlsf_assert(x); if (!(x)) { status--; } }
++
++ static void integrity_walker(void* ptr, size_t size, int used, void* user)
++ {
++ block_header_t* block = block_from_ptr(ptr);
++ integrity_t* integ = tlsf_cast(integrity_t*, user);
++ const int this_prev_status = block_is_prev_free(block) ? 1 : 0;
++ const int this_status = block_is_free(block) ? 1 : 0;
++ const size_t this_block_size = block_size(block);
++
++ int status = 0;
++ (void)used;
++ tlsf_insist(integ->prev_status == this_prev_status && "prev status incorrect");
++ tlsf_insist(size == this_block_size && "block size incorrect");
++
++ integ->prev_status = this_status;
++ integ->status += status;
++ }
++
++ int tlsf_check(tlsf_t tlsf)
++ {
++ int i, j;
++
++ control_t* control = tlsf_cast(control_t*, tlsf);
++ int status = 0;
++
++ /* Check that the free lists and bitmaps are accurate. */
++ for (i = 0; i < FL_INDEX_COUNT; ++i)
++ {
++ for (j = 0; j < SL_INDEX_COUNT; ++j)
++ {
++ const int fl_map = control->fl_bitmap & (1U << i);
++ const int sl_list = control->sl_bitmap[i];
++ const int sl_map = sl_list & (1U << j);
++ const block_header_t* block = control->blocks[i][j];
++
++ /* Check that first- and second-level lists agree. */
++ if (!fl_map)
++ {
++ tlsf_insist(!sl_map && "second-level map must be null");
++ }
++
++ if (!sl_map)
++ {
++ tlsf_insist(block == &control->block_null && "block list must be null");
++ continue;
++ }
++
++ /* Check that there is at least one free block. */
++ tlsf_insist(sl_list && "no free blocks in second-level map");
++ tlsf_insist(block != &control->block_null && "block should not be null");
++
++ while (block != &control->block_null)
++ {
++ int fli, sli;
++ tlsf_insist(block_is_free(block) && "block should be free");
++ tlsf_insist(!block_is_prev_free(block) && "blocks should have coalesced");
++ tlsf_insist(!block_is_free(block_next(block)) && "blocks should have coalesced");
++ tlsf_insist(block_is_prev_free(block_next(block)) && "block should be free");
++ tlsf_insist(block_size(block) >= block_size_min && "block not minimum size");
++
++ mapping_insert(block_size(block), &fli, &sli);
++ tlsf_insist(fli == i && sli == j && "block size indexed in wrong list");
++ block = block->next_free;
++ }
++ }
++ }
++
++ return status;
++ }
++
++ #undef tlsf_insist
++
++ static void default_walker(void* ptr, size_t size, int used, void* user)
++ {
++ (void)user;
++ printf("\t%p %s size: %x (%p)\n", ptr, used ? "used" : "free", (unsigned int)size, block_from_ptr(ptr));
++ }
++
++ void tlsf_walk_pool(pool_t pool, tlsf_walker walker, void* user)
++ {
++ tlsf_walker pool_walker = walker ? walker : default_walker;
++ block_header_t* block =
++ offset_to_block(pool, -(int)block_header_overhead);
++
++ while (block && !block_is_last(block))
++ {
++ pool_walker(
++ block_to_ptr(block),
++ block_size(block),
++ !block_is_free(block),
++ user);
++ block = block_next(block);
++ }
++ }
++
++ size_t tlsf_block_size(void* ptr)
++ {
++ size_t size = 0;
++ if (ptr)
++ {
++ const block_header_t* block = block_from_ptr(ptr);
++ size = block_size(block);
++ }
++ return size;
++ }
++
++ int tlsf_check_pool(pool_t pool)
++ {
++ /* Check that the blocks are physically correct. */
++ integrity_t integ = { 0, 0 };
++ tlsf_walk_pool(pool, integrity_walker, &integ);
++
++ return integ.status;
++ }
++
++ /*
++ ** Size of the TLSF structures in a given memory block passed to
++ ** tlsf_create, equal to the size of a control_t
++ */
++ size_t tlsf_size(void)
++ {
++ return sizeof(control_t);
++ }
++
++ size_t tlsf_align_size(void)
++ {
++ return ALIGN_SIZE;
++ }
++
++ size_t tlsf_block_size_min(void)
++ {
++ return block_size_min;
++ }
++
++ size_t tlsf_block_size_max(void)
++ {
++ return block_size_max;
++ }
++
++ /*
++ ** Overhead of the TLSF structures in a given memory block passed to
++ ** tlsf_add_pool, equal to the overhead of a free block and the
++ ** sentinel block.
++ */
++ size_t tlsf_pool_overhead(void)
++ {
++ return 2 * block_header_overhead;
++ }
++
++ size_t tlsf_alloc_overhead(void)
++ {
++ return block_header_overhead;
++ }
++
++ pool_t tlsf_add_pool(tlsf_t tlsf, void* mem, size_t bytes)
++ {
++ block_header_t* block;
++ block_header_t* next;
++
++ const size_t pool_overhead = tlsf_pool_overhead();
++ const size_t pool_bytes = align_down(bytes - pool_overhead, ALIGN_SIZE);
++
++ if (((ptrdiff_t)mem % ALIGN_SIZE) != 0)
++ {
++ printf("tlsf_add_pool: Memory must be aligned by %u bytes.\n",
++ (unsigned int)ALIGN_SIZE);
++ return 0;
++ }
++
++ if (pool_bytes < block_size_min || pool_bytes > block_size_max)
++ {
++ #if defined (TLSF_64BIT)
++ printf("tlsf_add_pool: Memory size must be between 0x%x and 0x%x00 bytes.\n",
++ (unsigned int)(pool_overhead + block_size_min),
++ (unsigned int)((pool_overhead + block_size_max) / 256));
++ #else
++ printf("tlsf_add_pool: Memory size must be between %u and %u bytes.\n",
++ (unsigned int)(pool_overhead + block_size_min),
++ (unsigned int)(pool_overhead + block_size_max));
++ #endif
++ return 0;
++ }
++
++ /*
++ ** Create the main free block. Offset the start of the block slightly
++ ** so that the prev_phys_block field falls outside of the pool -
++ ** it will never be used.
++ */
++ block = offset_to_block(mem, -(tlsfptr_t)block_header_overhead);
++ block_set_size(block, pool_bytes);
++ block_set_free(block);
++ block_set_prev_used(block);
++ block_insert(tlsf_cast(control_t*, tlsf), block);
++
++ /* Split the block to create a zero-size sentinel block. */
++ next = block_link_next(block);
++ block_set_size(next, 0);
++ block_set_used(next);
++ block_set_prev_free(next);
++
++ return mem;
++ }
++
++ void tlsf_remove_pool(tlsf_t tlsf, pool_t pool)
++ {
++ control_t* control = tlsf_cast(control_t*, tlsf);
++ block_header_t* block = offset_to_block(pool, -(int)block_header_overhead);
++
++ int fl = 0, sl = 0;
++
++ tlsf_assert(block_is_free(block) && "block should be free");
++ tlsf_assert(!block_is_free(block_next(block)) && "next block should not be free");
++ tlsf_assert(block_size(block_next(block)) == 0 && "next block size should be zero");
++
++ mapping_insert(block_size(block), &fl, &sl);
++ remove_free_block(control, block, fl, sl);
++ }
++
++ /*
++ ** TLSF main interface.
++ */
++
++ #if _DEBUG
++ int test_ffs_fls()
++ {
++ /* Verify ffs/fls work properly. */
++ int rv = 0;
++ rv += (tlsf_ffs(0) == -1) ? 0 : 0x1;
++ rv += (tlsf_fls(0) == -1) ? 0 : 0x2;
++ rv += (tlsf_ffs(1) == 0) ? 0 : 0x4;
++ rv += (tlsf_fls(1) == 0) ? 0 : 0x8;
++ rv += (tlsf_ffs(0x80000000) == 31) ? 0 : 0x10;
++ rv += (tlsf_ffs(0x80008000) == 15) ? 0 : 0x20;
++ rv += (tlsf_fls(0x80000008) == 31) ? 0 : 0x40;
++ rv += (tlsf_fls(0x7FFFFFFF) == 30) ? 0 : 0x80;
++
++ #if defined (TLSF_64BIT)
++ rv += (tlsf_fls_sizet(0x80000000) == 31) ? 0 : 0x100;
++ rv += (tlsf_fls_sizet(0x100000000) == 32) ? 0 : 0x200;
++ rv += (tlsf_fls_sizet(0xffffffffffffffff) == 63) ? 0 : 0x400;
++ #endif
++
++ if (rv)
++ {
++ printf("test_ffs_fls: %x ffs/fls tests failed.\n", rv);
++ }
++ return rv;
++ }
++ #endif
++
++ tlsf_t tlsf_create(void* mem)
++ {
++ #if _DEBUG
++ if (test_ffs_fls())
++ {
++ return 0;
++ }
++ #endif
++
++ if (((tlsfptr_t)mem % ALIGN_SIZE) != 0)
++ {
++ printf("tlsf_create: Memory must be aligned to %u bytes.\n",
++ (unsigned int)ALIGN_SIZE);
++ return 0;
++ }
++
++ control_construct(tlsf_cast(control_t*, mem));
++
++ return tlsf_cast(tlsf_t, mem);
++ }
++
++ tlsf_t tlsf_create_with_pool(void* mem, size_t bytes)
++ {
++ tlsf_t tlsf = tlsf_create(mem);
++ tlsf_add_pool(tlsf, (char*)mem + tlsf_size(), bytes - tlsf_size());
++ return tlsf;
++ }
++
++ void tlsf_destroy(tlsf_t tlsf)
++ {
++ /* Nothing to do. */
++ (void)tlsf;
++ }
++
++ pool_t tlsf_get_pool(tlsf_t tlsf)
++ {
++ return tlsf_cast(pool_t, (char*)tlsf + tlsf_size());
++ }
++
++ void* tlsf_malloc(tlsf_t tlsf, size_t size)
++ {
++ control_t* control = tlsf_cast(control_t*, tlsf);
++ const size_t adjust = adjust_request_size(size, ALIGN_SIZE);
++ block_header_t* block = block_locate_free(control, adjust);
++ return block_prepare_used(control, block, adjust);
++ }
++
++ void* tlsf_memalign(tlsf_t tlsf, size_t align, size_t size)
++ {
++ control_t* control = tlsf_cast(control_t*, tlsf);
++ const size_t adjust = adjust_request_size(size, ALIGN_SIZE);
++
++ /*
++ ** We must allocate an additional minimum block size bytes so that if
++ ** our free block will leave an alignment gap which is smaller, we can
++ ** trim a leading free block and release it back to the pool. We must
++ ** do this because the previous physical block is in use, therefore
++ ** the prev_phys_block field is not valid, and we can't simply adjust
++ ** the size of that block.
++ */
++ const size_t gap_minimum = sizeof(block_header_t);
++ const size_t size_with_gap = adjust_request_size(adjust + align + gap_minimum, align);
++
++ /*
++ ** If alignment is less than or equals base alignment, we're done.
++ ** If we requested 0 bytes, return null, as tlsf_malloc(0) does.
++ */
++ const size_t aligned_size = (adjust && align > ALIGN_SIZE) ? size_with_gap : adjust;
++
++ block_header_t* block = block_locate_free(control, aligned_size);
++
++ /* This can't be a static assert. */
++ tlsf_assert(sizeof(block_header_t) == block_size_min + block_header_overhead);
++
++ if (block)
++ {
++ void* ptr = block_to_ptr(block);
++ void* aligned = align_ptr(ptr, align);
++ size_t gap = tlsf_cast(size_t,
++ tlsf_cast(tlsfptr_t, aligned) - tlsf_cast(tlsfptr_t, ptr));
++
++ /* If gap size is too small, offset to next aligned boundary. */
++ if (gap && gap < gap_minimum)
++ {
++ const size_t gap_remain = gap_minimum - gap;
++ const size_t offset = tlsf_max(gap_remain, align);
++ const void* next_aligned = tlsf_cast(void*,
++ tlsf_cast(tlsfptr_t, aligned) + offset);
++
++ aligned = align_ptr(next_aligned, align);
++ gap = tlsf_cast(size_t,
++ tlsf_cast(tlsfptr_t, aligned) - tlsf_cast(tlsfptr_t, ptr));
++ }
++
++ if (gap)
++ {
++ tlsf_assert(gap >= gap_minimum && "gap size too small");
++ block = block_trim_free_leading(control, block, gap);
++ }
++ }
++
++ return block_prepare_used(control, block, adjust);
++ }
++
++ void tlsf_free(tlsf_t tlsf, void* ptr)
++ {
++ /* Don't attempt to free a NULL pointer. */
++ if (ptr)
++ {
++ control_t* control = tlsf_cast(control_t*, tlsf);
++ block_header_t* block = block_from_ptr(ptr);
++ tlsf_assert(!block_is_free(block) && "block already marked as free");
++ block_mark_as_free(block);
++ block = block_merge_prev(control, block);
++ block = block_merge_next(control, block);
++ block_insert(control, block);
++ }
++ }
++
++ /*
++ ** The TLSF block information provides us with enough information to
++ ** provide a reasonably intelligent implementation of realloc, growing or
++ ** shrinking the currently allocated block as required.
++ **
++ ** This routine handles the somewhat esoteric edge cases of realloc:
++ ** - a non-zero size with a null pointer will behave like malloc
++ ** - a zero size with a non-null pointer will behave like free
++ ** - a request that cannot be satisfied will leave the original buffer
++ ** untouched
++ ** - an extended buffer size will leave the newly-allocated area with
++ ** contents undefined
++ */
++ void* tlsf_realloc(tlsf_t tlsf, void* ptr, size_t size)
++ {
++ control_t* control = tlsf_cast(control_t*, tlsf);
++ void* p = 0;
++
++ /* Zero-size requests are treated as free. */
++ if (ptr && size == 0)
++ {
++ tlsf_free(tlsf, ptr);
++ }
++ /* Requests with NULL pointers are treated as malloc. */
++ else if (!ptr)
++ {
++ p = tlsf_malloc(tlsf, size);
++ }
++ else
++ {
++ block_header_t* block = block_from_ptr(ptr);
++ block_header_t* next = block_next(block);
++
++ const size_t cursize = block_size(block);
++ const size_t combined = cursize + block_size(next) + block_header_overhead;
++ const size_t adjust = adjust_request_size(size, ALIGN_SIZE);
++
++ tlsf_assert(!block_is_free(block) && "block already marked as free");
++
++ /*
++ ** If the next block is used, or when combined with the current
++ ** block, does not offer enough space, we must reallocate and copy.
++ */
++ if (adjust > cursize && (!block_is_free(next) || adjust > combined))
++ {
++ p = tlsf_malloc(tlsf, size);
++ if (p)
++ {
++ const size_t minsize = tlsf_min(cursize, size);
++ memcpy(p, ptr, minsize);
++ tlsf_free(tlsf, ptr);
++ }
++ }
++ else
++ {
++ /* Do we need to expand to the next block? */
++ if (adjust > cursize)
++ {
++ block_merge_next(control, block);
++ block_mark_as_used(block);
++ }
++
++ /* Trim the resulting block and return the original pointer. */
++ block_trim_used(control, block, adjust);
++ p = ptr;
++ }
++ }
++
++ return p;
++ }
++
++ } // namespace QtPrivate
++
++ QT_END_NAMESPACE