convert lvgl from submodule to a plain old directory

2 files changed, 1246 insertions, 0 deletions

diff --git a/lib/lvgl b/lib/lvgl
deleted file mode 160000
-Subproject 0732400e7b564dd0e7dc4a924619d8e19c5b23a
diff --git a/lib/lvgl/src/misc/lv_tlsf.c b/lib/lvgl/src/misc/lv_tlsf.c
new file mode 100644
index 00000000..27e0a46c
--- /dev/null
+++ b/lib/lvgl/src/misc/lv_tlsf.c
@@ -0,0 +1,1246 @@
+#include "../lv_conf_internal.h"
+#if LV_MEM_CUSTOM == 0
+
+#include <limits.h>
+#include "lv_tlsf.h"
+#include "lv_mem.h"
+#include "lv_log.h"
+#include "lv_assert.h"
+
+#undef  printf
+#define printf LV_LOG_ERROR
+
+#define TLSF_MAX_POOL_SIZE LV_MEM_SIZE
+
+#if !defined(_DEBUG)
+    #define _DEBUG 0
+#endif
+
+#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
+
+/*
+** Returns one plus the index of the most significant 1-bit of n,
+** or if n is zero, returns zero.
+*/
+#ifdef TLSF_64BIT
+    #define TLSF_FLS(n) ((n) & 0xffffffff00000000ull ? 32 + TLSF_FLS32((size_t)(n) >> 32) : TLSF_FLS32(n))
+#else
+    #define TLSF_FLS(n) TLSF_FLS32(n)
+#endif
+
+#define TLSF_FLS32(n) ((n) & 0xffff0000 ? 16 + TLSF_FLS16((n) >> 16) : TLSF_FLS16(n))
+#define TLSF_FLS16(n) ((n) & 0xff00     ?  8 + TLSF_FLS8 ((n) >>  8) : TLSF_FLS8 (n))
+#define TLSF_FLS8(n)  ((n) & 0xf0       ?  4 + TLSF_FLS4 ((n) >>  4) : TLSF_FLS4 (n))
+#define TLSF_FLS4(n)  ((n) & 0xc        ?  2 + TLSF_FLS2 ((n) >>  2) : TLSF_FLS2 (n))
+#define TLSF_FLS2(n)  ((n) & 0x2        ?  1 + TLSF_FLS1 ((n) >>  1) : TLSF_FLS1 (n))
+#define TLSF_FLS1(n)  ((n) & 0x1        ?  1 : 0)
+
+/*
+** Returns round up value of log2(n).
+** Note: it is used at compile time.
+*/
+#define TLSF_LOG2_CEIL(n) ((n) & (n - 1) ? TLSF_FLS(n) : TLSF_FLS(n) - 1)
+
+/*
+** 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. */
+
+/* Implement ffs in terms of fls. */
+tlsf_decl int tlsf_ffs(unsigned int word)
+{
+    const unsigned int reverse = word & (~word + 1);
+    return TLSF_FLS32(reverse) - 1;
+}
+
+tlsf_decl int tlsf_fls(unsigned int word)
+{
+    return TLSF_FLS32(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_MAX_POOL_SIZE)
+    FL_INDEX_MAX = TLSF_LOG2_CEIL(TLSF_MAX_POOL_SIZE),
+#elif 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.
+*/
+#define tlsf_assert LV_ASSERT
+
+#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_constructor(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;
+    LV_UNUSED(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 lv_tlsf_check(lv_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)
+{
+    LV_UNUSED(user);
+    printf("\t%p %s size: %x (%p)\n", ptr, used ? "used" : "free", (unsigned int)size, (void *)block_from_ptr(ptr));
+}
+
+void lv_tlsf_walk_pool(lv_pool_t pool, lv_tlsf_walker walker, void * user)
+{
+    lv_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 lv_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 lv_tlsf_check_pool(lv_pool_t pool)
+{
+    /* Check that the blocks are physically correct. */
+    integrity_t integ = { 0, 0 };
+    lv_tlsf_walk_pool(pool, integrity_walker, &integ);
+
+    return integ.status;
+}
+
+/*
+** Size of the TLSF structures in a given memory block passed to
+** lv_tlsf_create, equal to the size of a control_t
+*/
+size_t lv_tlsf_size(void)
+{
+    return sizeof(control_t);
+}
+
+size_t lv_tlsf_align_size(void)
+{
+    return ALIGN_SIZE;
+}
+
+size_t lv_tlsf_block_size_min(void)
+{
+    return block_size_min;
+}
+
+size_t lv_tlsf_block_size_max(void)
+{
+    return block_size_max;
+}
+
+/*
+** Overhead of the TLSF structures in a given memory block passed to
+** lv_tlsf_add_pool, equal to the overhead of a free block and the
+** sentinel block.
+*/
+size_t lv_tlsf_pool_overhead(void)
+{
+    return 2 * block_header_overhead;
+}
+
+size_t lv_tlsf_alloc_overhead(void)
+{
+    return block_header_overhead;
+}
+
+lv_pool_t lv_tlsf_add_pool(lv_tlsf_t tlsf, void * mem, size_t bytes)
+{
+    block_header_t * block;
+    block_header_t * next;
+
+    const size_t pool_overhead = lv_tlsf_pool_overhead();
+    const size_t pool_bytes = align_down(bytes - pool_overhead, ALIGN_SIZE);
+
+    if(((ptrdiff_t)mem % ALIGN_SIZE) != 0) {
+        printf("lv_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("lv_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("lv_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 lv_tlsf_remove_pool(lv_tlsf_t tlsf, lv_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
+
+lv_tlsf_t lv_tlsf_create(void * mem)
+{
+#if _DEBUG
+    if(test_ffs_fls()) {
+        return 0;
+    }
+#endif
+
+    if(((tlsfptr_t)mem % ALIGN_SIZE) != 0) {
+        printf("lv_tlsf_create: Memory must be aligned to %u bytes.\n",
+               (unsigned int)ALIGN_SIZE);
+        return 0;
+    }
+
+    control_constructor(tlsf_cast(control_t *, mem));
+
+    return tlsf_cast(lv_tlsf_t, mem);
+}
+
+lv_tlsf_t lv_tlsf_create_with_pool(void * mem, size_t bytes)
+{
+    lv_tlsf_t tlsf = lv_tlsf_create(mem);
+    lv_tlsf_add_pool(tlsf, (char *)mem + lv_tlsf_size(), bytes - lv_tlsf_size());
+    return tlsf;
+}
+
+void lv_tlsf_destroy(lv_tlsf_t tlsf)
+{
+    /* Nothing to do. */
+    LV_UNUSED(tlsf);
+}
+
+lv_pool_t lv_tlsf_get_pool(lv_tlsf_t tlsf)
+{
+    return tlsf_cast(lv_pool_t, (char *)tlsf + lv_tlsf_size());
+}
+
+void * lv_tlsf_malloc(lv_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 * lv_tlsf_memalign(lv_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 lv_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);
+}
+
+size_t lv_tlsf_free(lv_tlsf_t tlsf, const void * ptr)
+{
+    size_t size = 0;
+    /* 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");
+        size = block->size;
+        block_mark_as_free(block);
+        block = block_merge_prev(control, block);
+        block = block_merge_next(control, block);
+        block_insert(control, block);
+    }
+
+    return size;
+}
+
+/*
+** 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 * lv_tlsf_realloc(lv_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) {
+        lv_tlsf_free(tlsf, ptr);
+    }
+    /* Requests with NULL pointers are treated as malloc. */
+    else if(!ptr) {
+        p = lv_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);
+        if(size > cursize && adjust == 0) {
+            /* The request is probably too large, fail */
+            return NULL;
+        }
+
+        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 = lv_tlsf_malloc(tlsf, size);
+            if(p) {
+                const size_t minsize = tlsf_min(cursize, size);
+                lv_memcpy(p, ptr, minsize);
+                lv_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;
+}
+
+#endif /* LV_MEM_CUSTOM == 0 */