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-rw-r--r--src/malloc/malloc.c550
1 files changed, 0 insertions, 550 deletions
diff --git a/src/malloc/malloc.c b/src/malloc/malloc.c
deleted file mode 100644
index df3ea1be..00000000
--- a/src/malloc/malloc.c
+++ /dev/null
@@ -1,550 +0,0 @@
-#define _GNU_SOURCE
-#include <stdlib.h>
-#include <string.h>
-#include <limits.h>
-#include <stdint.h>
-#include <errno.h>
-#include <sys/mman.h>
-#include "libc.h"
-#include "atomic.h"
-#include "pthread_impl.h"
-#include "malloc_impl.h"
-
-#if defined(__GNUC__) && defined(__PIC__)
-#define inline inline __attribute__((always_inline))
-#endif
-
-static struct {
-	volatile uint64_t binmap;
-	struct bin bins[64];
-	volatile int split_merge_lock[2];
-} mal;
-
-int __malloc_replaced;
-
-/* Synchronization tools */
-
-static inline void lock(volatile int *lk)
-{
-	int need_locks = libc.need_locks;
-	if (need_locks) {
-		while(a_swap(lk, 1)) __wait(lk, lk+1, 1, 1);
-		if (need_locks < 0) libc.need_locks = 0;
-	}
-}
-
-static inline void unlock(volatile int *lk)
-{
-	if (lk[0]) {
-		a_store(lk, 0);
-		if (lk[1]) __wake(lk, 1, 1);
-	}
-}
-
-static inline void lock_bin(int i)
-{
-	lock(mal.bins[i].lock);
-	if (!mal.bins[i].head)
-		mal.bins[i].head = mal.bins[i].tail = BIN_TO_CHUNK(i);
-}
-
-static inline void unlock_bin(int i)
-{
-	unlock(mal.bins[i].lock);
-}
-
-static int first_set(uint64_t x)
-{
-#if 1
-	return a_ctz_64(x);
-#else
-	static const char debruijn64[64] = {
-		0, 1, 2, 53, 3, 7, 54, 27, 4, 38, 41, 8, 34, 55, 48, 28,
-		62, 5, 39, 46, 44, 42, 22, 9, 24, 35, 59, 56, 49, 18, 29, 11,
-		63, 52, 6, 26, 37, 40, 33, 47, 61, 45, 43, 21, 23, 58, 17, 10,
-		51, 25, 36, 32, 60, 20, 57, 16, 50, 31, 19, 15, 30, 14, 13, 12
-	};
-	static const char debruijn32[32] = {
-		0, 1, 23, 2, 29, 24, 19, 3, 30, 27, 25, 11, 20, 8, 4, 13,
-		31, 22, 28, 18, 26, 10, 7, 12, 21, 17, 9, 6, 16, 5, 15, 14
-	};
-	if (sizeof(long) < 8) {
-		uint32_t y = x;
-		if (!y) {
-			y = x>>32;
-			return 32 + debruijn32[(y&-y)*0x076be629 >> 27];
-		}
-		return debruijn32[(y&-y)*0x076be629 >> 27];
-	}
-	return debruijn64[(x&-x)*0x022fdd63cc95386dull >> 58];
-#endif
-}
-
-static const unsigned char bin_tab[60] = {
-	            32,33,34,35,36,36,37,37,38,38,39,39,
-	40,40,40,40,41,41,41,41,42,42,42,42,43,43,43,43,
-	44,44,44,44,44,44,44,44,45,45,45,45,45,45,45,45,
-	46,46,46,46,46,46,46,46,47,47,47,47,47,47,47,47,
-};
-
-static int bin_index(size_t x)
-{
-	x = x / SIZE_ALIGN - 1;
-	if (x <= 32) return x;
-	if (x < 512) return bin_tab[x/8-4];
-	if (x > 0x1c00) return 63;
-	return bin_tab[x/128-4] + 16;
-}
-
-static int bin_index_up(size_t x)
-{
-	x = x / SIZE_ALIGN - 1;
-	if (x <= 32) return x;
-	x--;
-	if (x < 512) return bin_tab[x/8-4] + 1;
-	return bin_tab[x/128-4] + 17;
-}
-
-#if 0
-void __dump_heap(int x)
-{
-	struct chunk *c;
-	int i;
-	for (c = (void *)mal.heap; CHUNK_SIZE(c); c = NEXT_CHUNK(c))
-		fprintf(stderr, "base %p size %zu (%d) flags %d/%d\n",
-			c, CHUNK_SIZE(c), bin_index(CHUNK_SIZE(c)),
-			c->csize & 15,
-			NEXT_CHUNK(c)->psize & 15);
-	for (i=0; i<64; i++) {
-		if (mal.bins[i].head != BIN_TO_CHUNK(i) && mal.bins[i].head) {
-			fprintf(stderr, "bin %d: %p\n", i, mal.bins[i].head);
-			if (!(mal.binmap & 1ULL<<i))
-				fprintf(stderr, "missing from binmap!\n");
-		} else if (mal.binmap & 1ULL<<i)
-			fprintf(stderr, "binmap wrongly contains %d!\n", i);
-	}
-}
-#endif
-
-/* This function returns true if the interval [old,new]
- * intersects the 'len'-sized interval below &libc.auxv
- * (interpreted as the main-thread stack) or below &b
- * (the current stack). It is used to defend against
- * buggy brk implementations that can cross the stack. */
-
-static int traverses_stack_p(uintptr_t old, uintptr_t new)
-{
-	const uintptr_t len = 8<<20;
-	uintptr_t a, b;
-
-	b = (uintptr_t)libc.auxv;
-	a = b > len ? b-len : 0;
-	if (new>a && old<b) return 1;
-
-	b = (uintptr_t)&b;
-	a = b > len ? b-len : 0;
-	if (new>a && old<b) return 1;
-
-	return 0;
-}
-
-/* Expand the heap in-place if brk can be used, or otherwise via mmap,
- * using an exponential lower bound on growth by mmap to make
- * fragmentation asymptotically irrelevant. The size argument is both
- * an input and an output, since the caller needs to know the size
- * allocated, which will be larger than requested due to page alignment
- * and mmap minimum size rules. The caller is responsible for locking
- * to prevent concurrent calls. */
-
-static void *__expand_heap(size_t *pn)
-{
-	static uintptr_t brk;
-	static unsigned mmap_step;
-	size_t n = *pn;
-
-	if (n > SIZE_MAX/2 - PAGE_SIZE) {
-		errno = ENOMEM;
-		return 0;
-	}
-	n += -n & PAGE_SIZE-1;
-
-	if (!brk) {
-		brk = __syscall(SYS_brk, 0);
-		brk += -brk & PAGE_SIZE-1;
-	}
-
-	if (n < SIZE_MAX-brk && !traverses_stack_p(brk, brk+n)
-	    && __syscall(SYS_brk, brk+n)==brk+n) {
-		*pn = n;
-		brk += n;
-		return (void *)(brk-n);
-	}
-
-	size_t min = (size_t)PAGE_SIZE << mmap_step/2;
-	if (n < min) n = min;
-	void *area = __mmap(0, n, PROT_READ|PROT_WRITE,
-		MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
-	if (area == MAP_FAILED) return 0;
-	*pn = n;
-	mmap_step++;
-	return area;
-}
-
-static struct chunk *expand_heap(size_t n)
-{
-	static void *end;
-	void *p;
-	struct chunk *w;
-
-	/* The argument n already accounts for the caller's chunk
-	 * overhead needs, but if the heap can't be extended in-place,
-	 * we need room for an extra zero-sized sentinel chunk. */
-	n += SIZE_ALIGN;
-
-	p = __expand_heap(&n);
-	if (!p) return 0;
-
-	/* If not just expanding existing space, we need to make a
-	 * new sentinel chunk below the allocated space. */
-	if (p != end) {
-		/* Valid/safe because of the prologue increment. */
-		n -= SIZE_ALIGN;
-		p = (char *)p + SIZE_ALIGN;
-		w = MEM_TO_CHUNK(p);
-		w->psize = 0 | C_INUSE;
-	}
-
-	/* Record new heap end and fill in footer. */
-	end = (char *)p + n;
-	w = MEM_TO_CHUNK(end);
-	w->psize = n | C_INUSE;
-	w->csize = 0 | C_INUSE;
-
-	/* Fill in header, which may be new or may be replacing a
-	 * zero-size sentinel header at the old end-of-heap. */
-	w = MEM_TO_CHUNK(p);
-	w->csize = n | C_INUSE;
-
-	return w;
-}
-
-static int adjust_size(size_t *n)
-{
-	/* Result of pointer difference must fit in ptrdiff_t. */
-	if (*n-1 > PTRDIFF_MAX - SIZE_ALIGN - PAGE_SIZE) {
-		if (*n) {
-			errno = ENOMEM;
-			return -1;
-		} else {
-			*n = SIZE_ALIGN;
-			return 0;
-		}
-	}
-	*n = (*n + OVERHEAD + SIZE_ALIGN - 1) & SIZE_MASK;
-	return 0;
-}
-
-static void unbin(struct chunk *c, int i)
-{
-	if (c->prev == c->next)
-		a_and_64(&mal.binmap, ~(1ULL<<i));
-	c->prev->next = c->next;
-	c->next->prev = c->prev;
-	c->csize |= C_INUSE;
-	NEXT_CHUNK(c)->psize |= C_INUSE;
-}
-
-static void bin_chunk(struct chunk *self, int i)
-{
-	self->next = BIN_TO_CHUNK(i);
-	self->prev = mal.bins[i].tail;
-	self->next->prev = self;
-	self->prev->next = self;
-	if (self->prev == BIN_TO_CHUNK(i))
-		a_or_64(&mal.binmap, 1ULL<<i);
-}
-
-static void trim(struct chunk *self, size_t n)
-{
-	size_t n1 = CHUNK_SIZE(self);
-	struct chunk *next, *split;
-
-	if (n >= n1 - DONTCARE) return;
-
-	next = NEXT_CHUNK(self);
-	split = (void *)((char *)self + n);
-
-	split->psize = n | C_INUSE;
-	split->csize = n1-n;
-	next->psize = n1-n;
-	self->csize = n | C_INUSE;
-
-	int i = bin_index(n1-n);
-	lock_bin(i);
-
-	bin_chunk(split, i);
-
-	unlock_bin(i);
-}
-
-void *malloc(size_t n)
-{
-	struct chunk *c;
-	int i, j;
-	uint64_t mask;
-
-	if (adjust_size(&n) < 0) return 0;
-
-	if (n > MMAP_THRESHOLD) {
-		size_t len = n + OVERHEAD + PAGE_SIZE - 1 & -PAGE_SIZE;
-		char *base = __mmap(0, len, PROT_READ|PROT_WRITE,
-			MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
-		if (base == (void *)-1) return 0;
-		c = (void *)(base + SIZE_ALIGN - OVERHEAD);
-		c->csize = len - (SIZE_ALIGN - OVERHEAD);
-		c->psize = SIZE_ALIGN - OVERHEAD;
-		return CHUNK_TO_MEM(c);
-	}
-
-	i = bin_index_up(n);
-	if (i<63 && (mal.binmap & (1ULL<<i))) {
-		lock_bin(i);
-		c = mal.bins[i].head;
-		if (c != BIN_TO_CHUNK(i) && CHUNK_SIZE(c)-n <= DONTCARE) {
-			unbin(c, i);
-			unlock_bin(i);
-			return CHUNK_TO_MEM(c);
-		}
-		unlock_bin(i);
-	}
-	lock(mal.split_merge_lock);
-	for (mask = mal.binmap & -(1ULL<<i); mask; mask -= (mask&-mask)) {
-		j = first_set(mask);
-		lock_bin(j);
-		c = mal.bins[j].head;
-		if (c != BIN_TO_CHUNK(j)) {
-			unbin(c, j);
-			unlock_bin(j);
-			break;
-		}
-		unlock_bin(j);
-	}
-	if (!mask) {
-		c = expand_heap(n);
-		if (!c) {
-			unlock(mal.split_merge_lock);
-			return 0;
-		}
-	}
-	trim(c, n);
-	unlock(mal.split_merge_lock);
-	return CHUNK_TO_MEM(c);
-}
-
-static size_t mal0_clear(char *p, size_t pagesz, size_t n)
-{
-#ifdef __GNUC__
-	typedef uint64_t __attribute__((__may_alias__)) T;
-#else
-	typedef unsigned char T;
-#endif
-	char *pp = p + n;
-	size_t i = (uintptr_t)pp & (pagesz - 1);
-	for (;;) {
-		pp = memset(pp - i, 0, i);
-		if (pp - p < pagesz) return pp - p;
-		for (i = pagesz; i; i -= 2*sizeof(T), pp -= 2*sizeof(T))
-		        if (((T *)pp)[-1] | ((T *)pp)[-2])
-				break;
-	}
-}
-
-void *calloc(size_t m, size_t n)
-{
-	if (n && m > (size_t)-1/n) {
-		errno = ENOMEM;
-		return 0;
-	}
-	n *= m;
-	void *p = malloc(n);
-	if (!p) return p;
-	if (!__malloc_replaced) {
-		if (IS_MMAPPED(MEM_TO_CHUNK(p)))
-			return p;
-		if (n >= PAGE_SIZE)
-			n = mal0_clear(p, PAGE_SIZE, n);
-	}
-	return memset(p, 0, n);
-}
-
-void *realloc(void *p, size_t n)
-{
-	struct chunk *self, *next;
-	size_t n0, n1;
-	void *new;
-
-	if (!p) return malloc(n);
-
-	if (adjust_size(&n) < 0) return 0;
-
-	self = MEM_TO_CHUNK(p);
-	n1 = n0 = CHUNK_SIZE(self);
-
-	if (n<=n0 && n0-n<=DONTCARE) return p;
-
-	if (IS_MMAPPED(self)) {
-		size_t extra = self->psize;
-		char *base = (char *)self - extra;
-		size_t oldlen = n0 + extra;
-		size_t newlen = n + extra;
-		/* Crash on realloc of freed chunk */
-		if (extra & 1) a_crash();
-		if (newlen < PAGE_SIZE && (new = malloc(n-OVERHEAD))) {
-			n0 = n;
-			goto copy_free_ret;
-		}
-		newlen = (newlen + PAGE_SIZE-1) & -PAGE_SIZE;
-		if (oldlen == newlen) return p;
-		base = __mremap(base, oldlen, newlen, MREMAP_MAYMOVE);
-		if (base == (void *)-1)
-			goto copy_realloc;
-		self = (void *)(base + extra);
-		self->csize = newlen - extra;
-		return CHUNK_TO_MEM(self);
-	}
-
-	next = NEXT_CHUNK(self);
-
-	/* Crash on corrupted footer (likely from buffer overflow) */
-	if (next->psize != self->csize) a_crash();
-
-	lock(mal.split_merge_lock);
-
-	size_t nsize = next->csize & C_INUSE ? 0 : CHUNK_SIZE(next);
-	if (n0+nsize >= n) {
-		int i = bin_index(nsize);
-		lock_bin(i);
-		if (!(next->csize & C_INUSE)) {
-			unbin(next, i);
-			unlock_bin(i);
-			next = NEXT_CHUNK(next);
-			self->csize = next->psize = n0+nsize | C_INUSE;
-			trim(self, n);
-			unlock(mal.split_merge_lock);
-			return CHUNK_TO_MEM(self);
-		}
-		unlock_bin(i);
-	}
-	unlock(mal.split_merge_lock);
-
-copy_realloc:
-	/* As a last resort, allocate a new chunk and copy to it. */
-	new = malloc(n-OVERHEAD);
-	if (!new) return 0;
-copy_free_ret:
-	memcpy(new, p, n0-OVERHEAD);
-	free(CHUNK_TO_MEM(self));
-	return new;
-}
-
-void __bin_chunk(struct chunk *self)
-{
-	struct chunk *next = NEXT_CHUNK(self);
-
-	/* Crash on corrupted footer (likely from buffer overflow) */
-	if (next->psize != self->csize) a_crash();
-
-	lock(mal.split_merge_lock);
-
-	size_t osize = CHUNK_SIZE(self), size = osize;
-
-	/* Since we hold split_merge_lock, only transition from free to
-	 * in-use can race; in-use to free is impossible */
-	size_t psize = self->psize & C_INUSE ? 0 : CHUNK_PSIZE(self);
-	size_t nsize = next->csize & C_INUSE ? 0 : CHUNK_SIZE(next);
-
-	if (psize) {
-		int i = bin_index(psize);
-		lock_bin(i);
-		if (!(self->psize & C_INUSE)) {
-			struct chunk *prev = PREV_CHUNK(self);
-			unbin(prev, i);
-			self = prev;
-			size += psize;
-		}
-		unlock_bin(i);
-	}
-	if (nsize) {
-		int i = bin_index(nsize);
-		lock_bin(i);
-		if (!(next->csize & C_INUSE)) {
-			unbin(next, i);
-			next = NEXT_CHUNK(next);
-			size += nsize;
-		}
-		unlock_bin(i);
-	}
-
-	int i = bin_index(size);
-	lock_bin(i);
-
-	self->csize = size;
-	next->psize = size;
-	bin_chunk(self, i);
-	unlock(mal.split_merge_lock);
-
-	/* Replace middle of large chunks with fresh zero pages */
-	if (size > RECLAIM && (size^(size-osize)) > size-osize) {
-		uintptr_t a = (uintptr_t)self + SIZE_ALIGN+PAGE_SIZE-1 & -PAGE_SIZE;
-		uintptr_t b = (uintptr_t)next - SIZE_ALIGN & -PAGE_SIZE;
-#if 1
-		__madvise((void *)a, b-a, MADV_DONTNEED);
-#else
-		__mmap((void *)a, b-a, PROT_READ|PROT_WRITE,
-			MAP_PRIVATE|MAP_ANONYMOUS|MAP_FIXED, -1, 0);
-#endif
-	}
-
-	unlock_bin(i);
-}
-
-static void unmap_chunk(struct chunk *self)
-{
-	size_t extra = self->psize;
-	char *base = (char *)self - extra;
-	size_t len = CHUNK_SIZE(self) + extra;
-	/* Crash on double free */
-	if (extra & 1) a_crash();
-	__munmap(base, len);
-}
-
-void free(void *p)
-{
-	if (!p) return;
-
-	struct chunk *self = MEM_TO_CHUNK(p);
-
-	if (IS_MMAPPED(self))
-		unmap_chunk(self);
-	else
-		__bin_chunk(self);
-}
-
-void __malloc_donate(char *start, char *end)
-{
-	size_t align_start_up = (SIZE_ALIGN-1) & (-(uintptr_t)start - OVERHEAD);
-	size_t align_end_down = (SIZE_ALIGN-1) & (uintptr_t)end;
-
-	/* Getting past this condition ensures that the padding for alignment
-	 * and header overhead will not overflow and will leave a nonzero
-	 * multiple of SIZE_ALIGN bytes between start and end. */
-	if (end - start <= OVERHEAD + align_start_up + align_end_down)
-		return;
-	start += align_start_up + OVERHEAD;
-	end   -= align_end_down;
-
-	struct chunk *c = MEM_TO_CHUNK(start), *n = MEM_TO_CHUNK(end);
-	c->psize = n->csize = C_INUSE;
-	c->csize = n->psize = C_INUSE | (end-start);
-	__bin_chunk(c);
-}
generated by cgit-pink 1.4.1 (git 2.36.1) at 2024-05-29 17:06:54 +0000