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Overview
Comment: | Added an experimental and completely untested wasm build of a bare-minimum cssminc. |
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Downloads: | Tarball | ZIP archive | SQL archive |
Timelines: | family | ancestors | trunk |
Files: | files | file ages | folders |
SHA3-256: |
a0cc37915b9eeba7bf1f75d068f51bad |
User & Date: | stephan 2022-07-10 15:02:25 |
Context
2022-07-10
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15:02 | Added an experimental and completely untested wasm build of a bare-minimum cssminc. Leaf check-in: a0cc37915b user: stephan tags: trunk | |
13:56 | Renamed Makefile to GNUmakefile. check-in: f22f86859b user: stephan tags: trunk | |
Changes
Changes to GNUmakefile.
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16 17 18 19 20 21 22 23 24 | $(MAKE) static=1 debug ?= 0 ifeq (0,$(debug)) CPPFLAGS += -DNDEBUG endif DOT_O := $(wildcard *.o) ifneq (,$(DOT_O)) | > | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | | 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 | $(MAKE) static=1 debug ?= 0 ifeq (0,$(debug)) CPPFLAGS += -DNDEBUG endif MAKEFILE := $(lastword $(MAKEFILE_LIST)) DOT_O := $(wildcard *.o) ifneq (,$(DOT_O)) $(DOT_O): $(MAKEFILE) endif cssminc.bin.o := cssminc.o cliapp.o cliapp.o: cliapp.c cssminc: $(cssminc.bin.o) $(CC) $(CFLAGS) $(CSSMINC_STATIC) -o $@ $^ cssminc.o: CPPFLAGS+=-DCSSMINC_MAIN libcssminc.o: cssminc.c cssminc.h $(CC) -c $(CFLAGS) -o $@ $< libcssminc.a: libcssminc.o $(AR) crs $@ $< all: cssminc libcssminc.a ######################################################################## # UNTESTED attempt to build cssminc as an emscripten-free wasm # file. EMSDK_HOME ?= $(HOME)/src/emsdk cssminc.wasm := cssminc.wasm clang.cflags := clang.sysroot += $(EMSDK_HOME)/upstream/emscripten/cache/sysroot clang.cflags += --sysroot=$(clang.sysroot) clang.cflags += -iwithsysroot/include/compat clang.cflags += --target=wasm32 clang.cflags += -DCSSMINC_WASM clang.cflags += -nostdlib clang.cflags += -UDEBUG -DNDEBUG=1 #clang.cflags += -emit-llvm clang.ldflags = --no-entry #clang.ldflags += --export-table clang.ldflags += --import-memory clang.ldflags += --export=cssminc_process_cstr_minimal clang.ldflags += -L$(clang.sysroot)/lib/wasm32-emscripten clang.ldflags += -lc $(cssminc.wasm): cssminc.c walloc.c $(MAKEFILE) @echo "ACHTUNG: wasm build results are untested!" clang -c cssminc.c $(clang.cflags) clang -c walloc.c $(clang.cflags) wasm-ld -o $@ cssminc.o walloc.o $(clang.ldflags) wasm-strip $@ chmod -x $@ wasm: $(cssminc.wasm) CLEAN_FILES += $(cssminc.wasm) $(cssminc.wasm).* # /wasm ######################################################################## .PHONY: clean distclean wasm CLEAN_FILES += $(wildcard *~ *.o cssminc libcssminc) clean: rm -f ./-nope $(CLEAN_FILES) DISTCLEAN_FILES += cssminc libcssminc.a libcssminc.o distclean: clean rm -f ./-nope $(DISTCLEAN_FILES) |
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Changes to cssminc.c.
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401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 | cs.out = cssminc_output_f_FILE; cs.outState = out; cs.in = cssminc_input_f_FILE; cs.inState = in; return cssminc_process(&cs); } int cssminc_output_f_cstr(void * state, unsigned char const * bytes, unsigned int n){ cssminc_state_cstr * const s = (cssminc_state_cstr *)state; if(n + s->outLen >= s->outAlloced){ unsigned int const i = (s->outLen ? ((s->outLen + n) * 3 / 2) + 1 : (n < 3 ? 3 : n + 1)); char * z; if(i<=n) return CSSMINC_RC_RANGE/*overflow*/; | > > > > > > > > > > > > > > > > > > > > > > > > | | | | 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 | cs.out = cssminc_output_f_FILE; cs.outState = out; cs.in = cssminc_input_f_FILE; cs.inState = in; return cssminc_process(&cs); } #if defined(CSSMINC_WASM) void * realloc(void *m, size_t n){ return 0; } static void cssminc__memcpy(void * dest, void const *src, unsigned n){ unsigned i; assert(!"realloc() should not be reached in a wasm build."); for(i=0; i<n; ++i) ((unsigned char*)dest)[i] =((unsigned char const*)src)[i]; } static void * cssminc__realloc(void * m, unsigned nOrig, unsigned nNew){ unsigned char * zNew = malloc(nNew); assert(nOrig<nNew); if(zNew){ cssminc__memcpy(zNew, m, nOrig); free(m); } return zNew; } #else #define cssminc__memcpy memcpy #define cssminc__realloc(M,O,N) realloc((M),(N)) #endif int cssminc_output_f_cstr(void * state, unsigned char const * bytes, unsigned int n){ cssminc_state_cstr * const s = (cssminc_state_cstr *)state; if(n + s->outLen >= s->outAlloced){ unsigned int const i = (s->outLen ? ((s->outLen + n) * 3 / 2) + 1 : (n < 3 ? 3 : n + 1)); char * z; if(i<=n) return CSSMINC_RC_RANGE/*overflow*/; z = cssminc__realloc(s->zOut, s->outAlloced, i); if(!z) return CSSMINC_RC_OOM; s->zOut = z; s->outAlloced = i; } cssminc__memcpy(s->zOut + s->outLen, bytes, n); s->zOut[s->outLen += n] = 0; return 0; } int cssminc_input_f_cstr(void * state, unsigned char * dest, unsigned int * n) { cssminc_state_cstr * const s = (cssminc_state_cstr *)state; if(!s->zCursor) s->zCursor = s->zStart; if(s->zCursor >= s->zEnd){ *n = 0; return 0; }else if(s->zCursor + *n > s->zEnd){ *n = (unsigned int)(s->zEnd - s->zCursor); } cssminc__memcpy(dest, s->zCursor, *n); s->zCursor += *n; return 0; } int cssminc_process_cstr(char const * zIn, int len, char ** zOut, unsigned int * outLen, cssminc_state * const opt){ cssminc_state cs = cssminc_state_empty; |
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474 475 476 477 478 479 480 | char * cssminc_process_cstr2(char const * zIn, int inLen, cssminc_state * const opt){ char * zOut = 0; cssminc_process_cstr(zIn, inLen, &zOut, NULL, opt); return zOut; } | > > > > | > > > > | 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 | char * cssminc_process_cstr2(char const * zIn, int inLen, cssminc_state * const opt){ char * zOut = 0; cssminc_process_cstr(zIn, inLen, &zOut, NULL, opt); return zOut; } char * cssminc_process_cstr_minimal(char const * zIn, int inLen){ char * zOut = 0; cssminc_process_cstr(zIn, inLen, &zOut, NULL, NULL); return zOut; } #undef cssminc__memcpy #undef cssminc__realloc /************************************************************************ The library code ends here. What follows is a quick-and-dirty main() app for the library.. ************************************************************************/ #if defined(CSSMINC_MAIN) #include "cliapp.h" #include <stdarg.h> /* va_list */ |
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Changes to cssminc.h.
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429 430 431 432 433 434 435 436 437 438 439 440 441 442 | the caller, who must eventually relinquish it using free(). The final argument may be NULL and is treated as documented for cssminc_process_cstr(). */ char * cssminc_process_cstr2(char const * zIn, int inLen, cssminc_state * const opt); /* LICENSE This software's source code, including accompanying documentation and demonstration applications, are licensed under the following conditions... | > > > > > | 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 | the caller, who must eventually relinquish it using free(). The final argument may be NULL and is treated as documented for cssminc_process_cstr(). */ char * cssminc_process_cstr2(char const * zIn, int inLen, cssminc_state * const opt); /** This proxy for cssmin_process_cstr() is intended solely for use in a bare-minimum configuration, e.g. in a WebAssembly build. */ char * cssminc_process_cstr_minimal(char const * zIn, int inLen); /* LICENSE This software's source code, including accompanying documentation and demonstration applications, are licensed under the following conditions... |
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Added walloc.c.
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IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. /*#include <stddef.h> #include <stdint.h>*/ typedef __SIZE_TYPE__ size_t; typedef __UINTPTR_TYPE__ uintptr_t; typedef __UINT8_TYPE__ uint8_t; #define NULL ((void *) 0) #define STATIC_ASSERT_EQ(a, b) _Static_assert((a) == (b), "eq") #ifndef NDEBUG #define ASSERT(x) do { if (!(x)) __builtin_trap(); } while (0) #else #define ASSERT(x) do { } while (0) #endif #define ASSERT_EQ(a,b) ASSERT((a) == (b)) static inline size_t max(size_t a, size_t b) { return a < b ? b : a; } static inline uintptr_t align(uintptr_t val, uintptr_t alignment) { return (val + alignment - 1) & ~(alignment - 1); } #define ASSERT_ALIGNED(x, y) ASSERT((x) == align((x), y)) #define CHUNK_SIZE 256 #define CHUNK_SIZE_LOG_2 8 #define CHUNK_MASK (CHUNK_SIZE - 1) STATIC_ASSERT_EQ(CHUNK_SIZE, 1 << CHUNK_SIZE_LOG_2); #define PAGE_SIZE 65536 #define PAGE_SIZE_LOG_2 16 #define PAGE_MASK (PAGE_SIZE - 1) STATIC_ASSERT_EQ(PAGE_SIZE, 1 << PAGE_SIZE_LOG_2); #define CHUNKS_PER_PAGE 256 STATIC_ASSERT_EQ(PAGE_SIZE, CHUNK_SIZE * CHUNKS_PER_PAGE); #define GRANULE_SIZE 8 #define GRANULE_SIZE_LOG_2 3 #define LARGE_OBJECT_THRESHOLD 256 #define LARGE_OBJECT_GRANULE_THRESHOLD 32 STATIC_ASSERT_EQ(GRANULE_SIZE, 1 << GRANULE_SIZE_LOG_2); STATIC_ASSERT_EQ(LARGE_OBJECT_THRESHOLD, LARGE_OBJECT_GRANULE_THRESHOLD * GRANULE_SIZE); struct chunk { char data[CHUNK_SIZE]; }; // There are small object pages for allocations of these sizes. #define FOR_EACH_SMALL_OBJECT_GRANULES(M) \ M(1) M(2) M(3) M(4) M(5) M(6) M(8) M(10) M(16) M(32) enum chunk_kind { #define DEFINE_SMALL_OBJECT_CHUNK_KIND(i) GRANULES_##i, FOR_EACH_SMALL_OBJECT_GRANULES(DEFINE_SMALL_OBJECT_CHUNK_KIND) #undef DEFINE_SMALL_OBJECT_CHUNK_KIND SMALL_OBJECT_CHUNK_KINDS, FREE_LARGE_OBJECT = 254, LARGE_OBJECT = 255 }; static const uint8_t small_object_granule_sizes[] = { #define SMALL_OBJECT_GRANULE_SIZE(i) i, FOR_EACH_SMALL_OBJECT_GRANULES(SMALL_OBJECT_GRANULE_SIZE) #undef SMALL_OBJECT_GRANULE_SIZE }; static enum chunk_kind granules_to_chunk_kind(unsigned granules) { #define TEST_GRANULE_SIZE(i) if (granules <= i) return GRANULES_##i; FOR_EACH_SMALL_OBJECT_GRANULES(TEST_GRANULE_SIZE); #undef TEST_GRANULE_SIZE return LARGE_OBJECT; } static unsigned chunk_kind_to_granules(enum chunk_kind kind) { switch (kind) { #define CHUNK_KIND_GRANULE_SIZE(i) case GRANULES_##i: return i; FOR_EACH_SMALL_OBJECT_GRANULES(CHUNK_KIND_GRANULE_SIZE); #undef CHUNK_KIND_GRANULE_SIZE default: return -1; } } // Given a pointer P returned by malloc(), we get a header pointer via // P&~PAGE_MASK, and a chunk index via (P&PAGE_MASK)/CHUNKS_PER_PAGE. If // chunk_kinds[chunk_idx] is [FREE_]LARGE_OBJECT, then the pointer is a large // object, otherwise the kind indicates the size in granules of the objects in // the chunk. struct page_header { uint8_t chunk_kinds[CHUNKS_PER_PAGE]; }; struct page { union { struct page_header header; struct chunk chunks[CHUNKS_PER_PAGE]; }; }; #define PAGE_HEADER_SIZE (sizeof (struct page_header)) #define FIRST_ALLOCATABLE_CHUNK 1 STATIC_ASSERT_EQ(PAGE_HEADER_SIZE, FIRST_ALLOCATABLE_CHUNK * CHUNK_SIZE); static struct page* get_page(void *ptr) { return (struct page*) (char*) (((uintptr_t) ptr) & ~PAGE_MASK); } static unsigned get_chunk_index(void *ptr) { return (((uintptr_t) ptr) & PAGE_MASK) / CHUNK_SIZE; } struct freelist { struct freelist *next; }; struct large_object { struct large_object *next; size_t size; }; #define LARGE_OBJECT_HEADER_SIZE (sizeof (struct large_object)) static inline void* get_large_object_payload(struct large_object *obj) { return ((char*) obj) + LARGE_OBJECT_HEADER_SIZE; } static inline struct large_object* get_large_object(void *ptr) { return (struct large_object*) (((char*) ptr) - LARGE_OBJECT_HEADER_SIZE); } static struct freelist *small_object_freelists[SMALL_OBJECT_CHUNK_KINDS]; static struct large_object *large_objects; extern void __heap_base; static size_t walloc_heap_size; static struct page* allocate_pages(size_t payload_size, size_t *n_allocated) { size_t needed = payload_size + PAGE_HEADER_SIZE; size_t heap_size = __builtin_wasm_memory_size(0) * PAGE_SIZE; uintptr_t base = heap_size; uintptr_t preallocated = 0, grow = 0; if (!walloc_heap_size) { // We are allocating the initial pages, if any. We skip the first 64 kB, // then take any additional space up to the memory size. uintptr_t heap_base = align((uintptr_t)&__heap_base, PAGE_SIZE); preallocated = heap_size - heap_base; // Preallocated pages. walloc_heap_size = preallocated; base -= preallocated; } if (preallocated < needed) { // Always grow the walloc heap at least by 50%. grow = align(max(walloc_heap_size / 2, needed - preallocated), PAGE_SIZE); ASSERT(grow); if (__builtin_wasm_memory_grow(0, grow >> PAGE_SIZE_LOG_2) == -1) { return NULL; } walloc_heap_size += grow; } struct page *ret = (struct page *)base; size_t size = grow + preallocated; ASSERT(size); ASSERT_ALIGNED(size, PAGE_SIZE); *n_allocated = size / PAGE_SIZE; return ret; } static char* allocate_chunk(struct page *page, unsigned idx, enum chunk_kind kind) { page->header.chunk_kinds[idx] = kind; return page->chunks[idx].data; } // It's possible for splitting to produce a large object of size 248 (256 minus // the header size) -- i.e. spanning a single chunk. In that case, push the // chunk back on the GRANULES_32 small object freelist. static void maybe_repurpose_single_chunk_large_objects_head(void) { if (large_objects->size < CHUNK_SIZE) { unsigned idx = get_chunk_index(large_objects); char *ptr = allocate_chunk(get_page(large_objects), idx, GRANULES_32); large_objects = large_objects->next; struct freelist* head = (struct freelist *)ptr; head->next = small_object_freelists[GRANULES_32]; small_object_freelists[GRANULES_32] = head; } } // If there have been any large-object frees since the last large object // allocation, go through the freelist and merge any adjacent objects. static int pending_large_object_compact = 0; static struct large_object** maybe_merge_free_large_object(struct large_object** prev) { struct large_object *obj = *prev; while (1) { char *end = get_large_object_payload(obj) + obj->size; ASSERT_ALIGNED((uintptr_t)end, CHUNK_SIZE); unsigned chunk = get_chunk_index(end); if (chunk < FIRST_ALLOCATABLE_CHUNK) { // Merging can't create a large object that newly spans the header chunk. // This check also catches the end-of-heap case. return prev; } struct page *page = get_page(end); if (page->header.chunk_kinds[chunk] != FREE_LARGE_OBJECT) { return prev; } struct large_object *next = (struct large_object*) end; struct large_object **prev_prev = &large_objects, *walk = large_objects; while (1) { ASSERT(walk); if (walk == next) { obj->size += LARGE_OBJECT_HEADER_SIZE + walk->size; *prev_prev = walk->next; if (prev == &walk->next) { prev = prev_prev; } break; } prev_prev = &walk->next; walk = walk->next; } } } static void maybe_compact_free_large_objects(void) { if (pending_large_object_compact) { pending_large_object_compact = 0; struct large_object **prev = &large_objects; while (*prev) { prev = &(*maybe_merge_free_large_object(prev))->next; } } } // Allocate a large object with enough space for SIZE payload bytes. Returns a // large object with a header, aligned on a chunk boundary, whose payload size // may be larger than SIZE, and whose total size (header included) is // chunk-aligned. Either a suitable allocation is found in the large object // freelist, or we ask the OS for some more pages and treat those pages as a // large object. If the allocation fits in that large object and there's more // than an aligned chunk's worth of data free at the end, the large object is // split. // // The return value's corresponding chunk in the page as starting a large // object. static struct large_object* allocate_large_object(size_t size) { maybe_compact_free_large_objects(); struct large_object *best = NULL, **best_prev = &large_objects; size_t best_size = -1; for (struct large_object **prev = &large_objects, *walk = large_objects; walk; prev = &walk->next, walk = walk->next) { if (walk->size >= size && walk->size < best_size) { best_size = walk->size; best = walk; best_prev = prev; if (best_size + LARGE_OBJECT_HEADER_SIZE == align(size + LARGE_OBJECT_HEADER_SIZE, CHUNK_SIZE)) // Not going to do any better than this; just return it. break; } } if (!best) { // The large object freelist doesn't have an object big enough for this // allocation. Allocate one or more pages from the OS, and treat that new // sequence of pages as a fresh large object. It will be split if // necessary. size_t size_with_header = size + sizeof(struct large_object); size_t n_allocated = 0; struct page *page = allocate_pages(size_with_header, &n_allocated); if (!page) { return NULL; } char *ptr = allocate_chunk(page, FIRST_ALLOCATABLE_CHUNK, LARGE_OBJECT); best = (struct large_object *)ptr; size_t page_header = ptr - ((char*) page); best->next = large_objects; best->size = best_size = n_allocated * PAGE_SIZE - page_header - LARGE_OBJECT_HEADER_SIZE; ASSERT(best_size >= size_with_header); } allocate_chunk(get_page(best), get_chunk_index(best), LARGE_OBJECT); struct large_object *next = best->next; *best_prev = next; size_t tail_size = (best_size - size) & ~CHUNK_MASK; if (tail_size) { // The best-fitting object has 1 or more aligned chunks free after the // requested allocation; split the tail off into a fresh aligned object. struct page *start_page = get_page(best); char *start = get_large_object_payload(best); char *end = start + best_size; if (start_page == get_page(end - tail_size - 1)) { // The allocation does not span a page boundary; yay. ASSERT_ALIGNED((uintptr_t)end, CHUNK_SIZE); } else if (size < PAGE_SIZE - LARGE_OBJECT_HEADER_SIZE - CHUNK_SIZE) { // If the allocation itself smaller than a page, split off the head, then // fall through to maybe split the tail. ASSERT_ALIGNED((uintptr_t)end, PAGE_SIZE); size_t first_page_size = PAGE_SIZE - (((uintptr_t)start) & PAGE_MASK); struct large_object *head = best; allocate_chunk(start_page, get_chunk_index(start), FREE_LARGE_OBJECT); head->size = first_page_size; head->next = large_objects; large_objects = head; maybe_repurpose_single_chunk_large_objects_head(); struct page *next_page = start_page + 1; char *ptr = allocate_chunk(next_page, FIRST_ALLOCATABLE_CHUNK, LARGE_OBJECT); best = (struct large_object *) ptr; best->size = best_size = best_size - first_page_size - CHUNK_SIZE - LARGE_OBJECT_HEADER_SIZE; ASSERT(best_size >= size); start = get_large_object_payload(best); tail_size = (best_size - size) & ~CHUNK_MASK; } else { // A large object that spans more than one page will consume all of its // tail pages. Therefore if the split traverses a page boundary, round up // to page size. ASSERT_ALIGNED((uintptr_t)end, PAGE_SIZE); size_t first_page_size = PAGE_SIZE - (((uintptr_t)start) & PAGE_MASK); size_t tail_pages_size = align(size - first_page_size, PAGE_SIZE); size = first_page_size + tail_pages_size; tail_size = best_size - size; } best->size -= tail_size; unsigned tail_idx = get_chunk_index(end - tail_size); while (tail_idx < FIRST_ALLOCATABLE_CHUNK && tail_size) { // We would be splitting in a page header; don't do that. tail_size -= CHUNK_SIZE; tail_idx++; } if (tail_size) { struct page *page = get_page(end - tail_size); char *tail_ptr = allocate_chunk(page, tail_idx, FREE_LARGE_OBJECT); struct large_object *tail = (struct large_object *) tail_ptr; tail->next = large_objects; tail->size = tail_size - LARGE_OBJECT_HEADER_SIZE; ASSERT_ALIGNED((uintptr_t)(get_large_object_payload(tail) + tail->size), CHUNK_SIZE); large_objects = tail; maybe_repurpose_single_chunk_large_objects_head(); } } ASSERT_ALIGNED((uintptr_t)(get_large_object_payload(best) + best->size), CHUNK_SIZE); return best; } static struct freelist* obtain_small_objects(enum chunk_kind kind) { struct freelist** whole_chunk_freelist = &small_object_freelists[GRANULES_32]; void *chunk; if (*whole_chunk_freelist) { chunk = *whole_chunk_freelist; *whole_chunk_freelist = (*whole_chunk_freelist)->next; } else { chunk = allocate_large_object(0); if (!chunk) { return NULL; } } char *ptr = allocate_chunk(get_page(chunk), get_chunk_index(chunk), kind); char *end = ptr + CHUNK_SIZE; struct freelist *next = NULL; size_t size = chunk_kind_to_granules(kind) * GRANULE_SIZE; for (size_t i = size; i <= CHUNK_SIZE; i += size) { struct freelist *head = (struct freelist*) (end - i); head->next = next; next = head; } return next; } static inline size_t size_to_granules(size_t size) { return (size + GRANULE_SIZE - 1) >> GRANULE_SIZE_LOG_2; } static struct freelist** get_small_object_freelist(enum chunk_kind kind) { ASSERT(kind < SMALL_OBJECT_CHUNK_KINDS); return &small_object_freelists[kind]; } static void* allocate_small(enum chunk_kind kind) { struct freelist **loc = get_small_object_freelist(kind); if (!*loc) { struct freelist *freelist = obtain_small_objects(kind); if (!freelist) { return NULL; } *loc = freelist; } struct freelist *ret = *loc; *loc = ret->next; return (void *) ret; } static void* allocate_large(size_t size) { struct large_object *obj = allocate_large_object(size); return obj ? get_large_object_payload(obj) : NULL; } void* malloc(size_t size) { size_t granules = size_to_granules(size); enum chunk_kind kind = granules_to_chunk_kind(granules); return (kind == LARGE_OBJECT) ? allocate_large(size) : allocate_small(kind); } void free(void *ptr) { if (!ptr) return; struct page *page = get_page(ptr); unsigned chunk = get_chunk_index(ptr); uint8_t kind = page->header.chunk_kinds[chunk]; if (kind == LARGE_OBJECT) { struct large_object *obj = get_large_object(ptr); obj->next = large_objects; large_objects = obj; allocate_chunk(page, chunk, FREE_LARGE_OBJECT); pending_large_object_compact = 1; } else { size_t granules = kind; struct freelist **loc = get_small_object_freelist(granules); struct freelist *obj = ptr; obj->next = *loc; *loc = obj; } } |