diff options
Diffstat (limited to 'thirdparty/libwebp/src/utils')
-rw-r--r-- | thirdparty/libwebp/src/utils/bit_reader_inl_utils.h | 9 | ||||
-rw-r--r-- | thirdparty/libwebp/src/utils/bit_reader_utils.c | 7 | ||||
-rw-r--r-- | thirdparty/libwebp/src/utils/bit_reader_utils.h | 10 | ||||
-rw-r--r-- | thirdparty/libwebp/src/utils/bit_writer_utils.c | 4 | ||||
-rw-r--r-- | thirdparty/libwebp/src/utils/color_cache_utils.c | 22 | ||||
-rw-r--r-- | thirdparty/libwebp/src/utils/huffman_encode_utils.c | 5 | ||||
-rw-r--r-- | thirdparty/libwebp/src/utils/huffman_encode_utils.h | 2 | ||||
-rw-r--r-- | thirdparty/libwebp/src/utils/quant_levels_dec_utils.c | 2 | ||||
-rw-r--r-- | thirdparty/libwebp/src/utils/rescaler_utils.c | 114 | ||||
-rw-r--r-- | thirdparty/libwebp/src/utils/rescaler_utils.h | 13 | ||||
-rw-r--r-- | thirdparty/libwebp/src/utils/utils.c | 13 | ||||
-rw-r--r-- | thirdparty/libwebp/src/utils/utils.h | 28 |
12 files changed, 125 insertions, 104 deletions
diff --git a/thirdparty/libwebp/src/utils/bit_reader_inl_utils.h b/thirdparty/libwebp/src/utils/bit_reader_inl_utils.h index 46b3880706..404b9a6d8c 100644 --- a/thirdparty/libwebp/src/utils/bit_reader_inl_utils.h +++ b/thirdparty/libwebp/src/utils/bit_reader_inl_utils.h @@ -55,7 +55,7 @@ void VP8LoadFinalBytes(VP8BitReader* const br); // makes sure br->value_ has at least BITS bits worth of data static WEBP_UBSAN_IGNORE_UNDEF WEBP_INLINE -void VP8LoadNewBytes(VP8BitReader* const br) { +void VP8LoadNewBytes(VP8BitReader* WEBP_RESTRICT const br) { assert(br != NULL && br->buf_ != NULL); // Read 'BITS' bits at a time if possible. if (br->buf_ < br->buf_max_) { @@ -104,7 +104,7 @@ void VP8LoadNewBytes(VP8BitReader* const br) { } // Read a bit with proba 'prob'. Speed-critical function! -static WEBP_INLINE int VP8GetBit(VP8BitReader* const br, +static WEBP_INLINE int VP8GetBit(VP8BitReader* WEBP_RESTRICT const br, int prob, const char label[]) { // Don't move this declaration! It makes a big speed difference to store // 'range' *before* calling VP8LoadNewBytes(), even if this function doesn't @@ -137,7 +137,8 @@ static WEBP_INLINE int VP8GetBit(VP8BitReader* const br, // simplified version of VP8GetBit() for prob=0x80 (note shift is always 1 here) static WEBP_UBSAN_IGNORE_UNSIGNED_OVERFLOW WEBP_INLINE -int VP8GetSigned(VP8BitReader* const br, int v, const char label[]) { +int VP8GetSigned(VP8BitReader* WEBP_RESTRICT const br, int v, + const char label[]) { if (br->bits_ < 0) { VP8LoadNewBytes(br); } @@ -155,7 +156,7 @@ int VP8GetSigned(VP8BitReader* const br, int v, const char label[]) { } } -static WEBP_INLINE int VP8GetBitAlt(VP8BitReader* const br, +static WEBP_INLINE int VP8GetBitAlt(VP8BitReader* WEBP_RESTRICT const br, int prob, const char label[]) { // Don't move this declaration! It makes a big speed difference to store // 'range' *before* calling VP8LoadNewBytes(), even if this function doesn't diff --git a/thirdparty/libwebp/src/utils/bit_reader_utils.c b/thirdparty/libwebp/src/utils/bit_reader_utils.c index 60271c0ae0..857cd60988 100644 --- a/thirdparty/libwebp/src/utils/bit_reader_utils.c +++ b/thirdparty/libwebp/src/utils/bit_reader_utils.c @@ -41,14 +41,7 @@ void VP8InitBitReader(VP8BitReader* const br, br->bits_ = -8; // to load the very first 8bits br->eof_ = 0; VP8BitReaderSetBuffer(br, start, size); -// -- GODOT -- begin -#ifdef JAVASCRIPT_ENABLED // html5 required aligned reads - while(((uintptr_t)br->buf_ & 1) != 0 && !br->eof_) - VP8LoadFinalBytes(br); -#else VP8LoadNewBytes(br); -#endif -// -- GODOT -- end } void VP8RemapBitReader(VP8BitReader* const br, ptrdiff_t offset) { diff --git a/thirdparty/libwebp/src/utils/bit_reader_utils.h b/thirdparty/libwebp/src/utils/bit_reader_utils.h index 199dacf224..e64156e318 100644 --- a/thirdparty/libwebp/src/utils/bit_reader_utils.h +++ b/thirdparty/libwebp/src/utils/bit_reader_utils.h @@ -58,12 +58,6 @@ extern "C" { // BITS can be any multiple of 8 from 8 to 56 (inclusive). // Pick values that fit natural register size. -// -- GODOT -- start -#ifdef JAVASCRIPT_ENABLED -#define BITS 16 -#else -// -- GODOT -- end - #if defined(__i386__) || defined(_M_IX86) // x86 32bit #define BITS 24 #elif defined(__x86_64__) || defined(_M_X64) // x86 64bit @@ -78,10 +72,6 @@ extern "C" { #define BITS 24 #endif -// -- GODOT -- start -#endif -// -- GODOT -- end - //------------------------------------------------------------------------------ // Derived types and constants: // bit_t = natural register type for storing 'value_' (which is BITS+8 bits) diff --git a/thirdparty/libwebp/src/utils/bit_writer_utils.c b/thirdparty/libwebp/src/utils/bit_writer_utils.c index bef0e31ca5..2f408508f1 100644 --- a/thirdparty/libwebp/src/utils/bit_writer_utils.c +++ b/thirdparty/libwebp/src/utils/bit_writer_utils.c @@ -278,7 +278,7 @@ void VP8LPutBitsFlushBits(VP8LBitWriter* const bw) { // If needed, make some room by flushing some bits out. if (bw->cur_ + VP8L_WRITER_BYTES > bw->end_) { const uint64_t extra_size = (bw->end_ - bw->buf_) + MIN_EXTRA_SIZE; - if (extra_size != (size_t)extra_size || + if (!CheckSizeOverflow(extra_size) || !VP8LBitWriterResize(bw, (size_t)extra_size)) { bw->cur_ = bw->buf_; bw->error_ = 1; @@ -314,7 +314,7 @@ void VP8LPutBitsInternal(VP8LBitWriter* const bw, uint32_t bits, int n_bits) { while (used >= VP8L_WRITER_BITS) { if (bw->cur_ + VP8L_WRITER_BYTES > bw->end_) { const uint64_t extra_size = (bw->end_ - bw->buf_) + MIN_EXTRA_SIZE; - if (extra_size != (size_t)extra_size || + if (!CheckSizeOverflow(extra_size) || !VP8LBitWriterResize(bw, (size_t)extra_size)) { bw->cur_ = bw->buf_; bw->error_ = 1; diff --git a/thirdparty/libwebp/src/utils/color_cache_utils.c b/thirdparty/libwebp/src/utils/color_cache_utils.c index b09f538e8b..7b5222b6e5 100644 --- a/thirdparty/libwebp/src/utils/color_cache_utils.c +++ b/thirdparty/libwebp/src/utils/color_cache_utils.c @@ -20,22 +20,22 @@ //------------------------------------------------------------------------------ // VP8LColorCache. -int VP8LColorCacheInit(VP8LColorCache* const cc, int hash_bits) { +int VP8LColorCacheInit(VP8LColorCache* const color_cache, int hash_bits) { const int hash_size = 1 << hash_bits; - assert(cc != NULL); + assert(color_cache != NULL); assert(hash_bits > 0); - cc->colors_ = (uint32_t*)WebPSafeCalloc((uint64_t)hash_size, - sizeof(*cc->colors_)); - if (cc->colors_ == NULL) return 0; - cc->hash_shift_ = 32 - hash_bits; - cc->hash_bits_ = hash_bits; + color_cache->colors_ = (uint32_t*)WebPSafeCalloc( + (uint64_t)hash_size, sizeof(*color_cache->colors_)); + if (color_cache->colors_ == NULL) return 0; + color_cache->hash_shift_ = 32 - hash_bits; + color_cache->hash_bits_ = hash_bits; return 1; } -void VP8LColorCacheClear(VP8LColorCache* const cc) { - if (cc != NULL) { - WebPSafeFree(cc->colors_); - cc->colors_ = NULL; +void VP8LColorCacheClear(VP8LColorCache* const color_cache) { + if (color_cache != NULL) { + WebPSafeFree(color_cache->colors_); + color_cache->colors_ = NULL; } } diff --git a/thirdparty/libwebp/src/utils/huffman_encode_utils.c b/thirdparty/libwebp/src/utils/huffman_encode_utils.c index 6f3b1bbe02..585db91951 100644 --- a/thirdparty/libwebp/src/utils/huffman_encode_utils.c +++ b/thirdparty/libwebp/src/utils/huffman_encode_utils.c @@ -161,7 +161,7 @@ static void SetBitDepths(const HuffmanTree* const tree, // especially when population counts are longer than 2**tree_limit, but // we are not planning to use this with extremely long blocks. // -// See http://en.wikipedia.org/wiki/Huffman_coding +// See https://en.wikipedia.org/wiki/Huffman_coding static void GenerateOptimalTree(const uint32_t* const histogram, int histogram_size, HuffmanTree* tree, int tree_depth_limit, @@ -404,8 +404,7 @@ static void ConvertBitDepthsToSymbols(HuffmanTreeCode* const tree) { // Main entry point void VP8LCreateHuffmanTree(uint32_t* const histogram, int tree_depth_limit, - uint8_t* const buf_rle, - HuffmanTree* const huff_tree, + uint8_t* const buf_rle, HuffmanTree* const huff_tree, HuffmanTreeCode* const huff_code) { const int num_symbols = huff_code->num_symbols; memset(buf_rle, 0, num_symbols * sizeof(*buf_rle)); diff --git a/thirdparty/libwebp/src/utils/huffman_encode_utils.h b/thirdparty/libwebp/src/utils/huffman_encode_utils.h index 3e6763ce49..3f7f1d8074 100644 --- a/thirdparty/libwebp/src/utils/huffman_encode_utils.h +++ b/thirdparty/libwebp/src/utils/huffman_encode_utils.h @@ -51,7 +51,7 @@ int VP8LCreateCompressedHuffmanTree(const HuffmanTreeCode* const tree, // huffman code tree. void VP8LCreateHuffmanTree(uint32_t* const histogram, int tree_depth_limit, uint8_t* const buf_rle, HuffmanTree* const huff_tree, - HuffmanTreeCode* const tree); + HuffmanTreeCode* const huff_code); #ifdef __cplusplus } diff --git a/thirdparty/libwebp/src/utils/quant_levels_dec_utils.c b/thirdparty/libwebp/src/utils/quant_levels_dec_utils.c index f65b6cdbb6..97e7893704 100644 --- a/thirdparty/libwebp/src/utils/quant_levels_dec_utils.c +++ b/thirdparty/libwebp/src/utils/quant_levels_dec_utils.c @@ -30,7 +30,7 @@ #define DFIX 4 // extra precision for ordered dithering #define DSIZE 4 // dithering size (must be a power of two) -// cf. http://en.wikipedia.org/wiki/Ordered_dithering +// cf. https://en.wikipedia.org/wiki/Ordered_dithering static const uint8_t kOrderedDither[DSIZE][DSIZE] = { { 0, 8, 2, 10 }, // coefficients are in DFIX fixed-point precision { 12, 4, 14, 6 }, diff --git a/thirdparty/libwebp/src/utils/rescaler_utils.c b/thirdparty/libwebp/src/utils/rescaler_utils.c index 4bcae24af5..a0581a14b1 100644 --- a/thirdparty/libwebp/src/utils/rescaler_utils.c +++ b/thirdparty/libwebp/src/utils/rescaler_utils.c @@ -12,66 +12,74 @@ // Author: Skal (pascal.massimino@gmail.com) #include <assert.h> +#include <limits.h> #include <stdlib.h> #include <string.h> #include "src/dsp/dsp.h" #include "src/utils/rescaler_utils.h" +#include "src/utils/utils.h" //------------------------------------------------------------------------------ -void WebPRescalerInit(WebPRescaler* const wrk, int src_width, int src_height, - uint8_t* const dst, - int dst_width, int dst_height, int dst_stride, - int num_channels, rescaler_t* const work) { +int WebPRescalerInit(WebPRescaler* const rescaler, + int src_width, int src_height, + uint8_t* const dst, + int dst_width, int dst_height, int dst_stride, + int num_channels, rescaler_t* const work) { const int x_add = src_width, x_sub = dst_width; const int y_add = src_height, y_sub = dst_height; - wrk->x_expand = (src_width < dst_width); - wrk->y_expand = (src_height < dst_height); - wrk->src_width = src_width; - wrk->src_height = src_height; - wrk->dst_width = dst_width; - wrk->dst_height = dst_height; - wrk->src_y = 0; - wrk->dst_y = 0; - wrk->dst = dst; - wrk->dst_stride = dst_stride; - wrk->num_channels = num_channels; + const uint64_t total_size = 2ull * dst_width * num_channels * sizeof(*work); + if (!CheckSizeOverflow(total_size)) return 0; + + rescaler->x_expand = (src_width < dst_width); + rescaler->y_expand = (src_height < dst_height); + rescaler->src_width = src_width; + rescaler->src_height = src_height; + rescaler->dst_width = dst_width; + rescaler->dst_height = dst_height; + rescaler->src_y = 0; + rescaler->dst_y = 0; + rescaler->dst = dst; + rescaler->dst_stride = dst_stride; + rescaler->num_channels = num_channels; // for 'x_expand', we use bilinear interpolation - wrk->x_add = wrk->x_expand ? (x_sub - 1) : x_add; - wrk->x_sub = wrk->x_expand ? (x_add - 1) : x_sub; - if (!wrk->x_expand) { // fx_scale is not used otherwise - wrk->fx_scale = WEBP_RESCALER_FRAC(1, wrk->x_sub); + rescaler->x_add = rescaler->x_expand ? (x_sub - 1) : x_add; + rescaler->x_sub = rescaler->x_expand ? (x_add - 1) : x_sub; + if (!rescaler->x_expand) { // fx_scale is not used otherwise + rescaler->fx_scale = WEBP_RESCALER_FRAC(1, rescaler->x_sub); } // vertical scaling parameters - wrk->y_add = wrk->y_expand ? y_add - 1 : y_add; - wrk->y_sub = wrk->y_expand ? y_sub - 1 : y_sub; - wrk->y_accum = wrk->y_expand ? wrk->y_sub : wrk->y_add; - if (!wrk->y_expand) { + rescaler->y_add = rescaler->y_expand ? y_add - 1 : y_add; + rescaler->y_sub = rescaler->y_expand ? y_sub - 1 : y_sub; + rescaler->y_accum = rescaler->y_expand ? rescaler->y_sub : rescaler->y_add; + if (!rescaler->y_expand) { // This is WEBP_RESCALER_FRAC(dst_height, x_add * y_add) without the cast. - // Its value is <= WEBP_RESCALER_ONE, because dst_height <= wrk->y_add, and - // wrk->x_add >= 1; - const uint64_t ratio = - (uint64_t)dst_height * WEBP_RESCALER_ONE / (wrk->x_add * wrk->y_add); + // Its value is <= WEBP_RESCALER_ONE, because dst_height <= rescaler->y_add + // and rescaler->x_add >= 1; + const uint64_t num = (uint64_t)dst_height * WEBP_RESCALER_ONE; + const uint64_t den = (uint64_t)rescaler->x_add * rescaler->y_add; + const uint64_t ratio = num / den; if (ratio != (uint32_t)ratio) { // When ratio == WEBP_RESCALER_ONE, we can't represent the ratio with the // current fixed-point precision. This happens when src_height == - // wrk->y_add (which == src_height), and wrk->x_add == 1. + // rescaler->y_add (which == src_height), and rescaler->x_add == 1. // => We special-case fxy_scale = 0, in WebPRescalerExportRow(). - wrk->fxy_scale = 0; + rescaler->fxy_scale = 0; } else { - wrk->fxy_scale = (uint32_t)ratio; + rescaler->fxy_scale = (uint32_t)ratio; } - wrk->fy_scale = WEBP_RESCALER_FRAC(1, wrk->y_sub); + rescaler->fy_scale = WEBP_RESCALER_FRAC(1, rescaler->y_sub); } else { - wrk->fy_scale = WEBP_RESCALER_FRAC(1, wrk->x_add); - // wrk->fxy_scale is unused here. + rescaler->fy_scale = WEBP_RESCALER_FRAC(1, rescaler->x_add); + // rescaler->fxy_scale is unused here. } - wrk->irow = work; - wrk->frow = work + num_channels * dst_width; - memset(work, 0, 2 * dst_width * num_channels * sizeof(*work)); + rescaler->irow = work; + rescaler->frow = work + num_channels * dst_width; + memset(work, 0, (size_t)total_size); WebPRescalerDspInit(); + return 1; } int WebPRescalerGetScaledDimensions(int src_width, int src_height, @@ -82,6 +90,7 @@ int WebPRescalerGetScaledDimensions(int src_width, int src_height, { int width = *scaled_width; int height = *scaled_height; + const int max_size = INT_MAX / 2; // if width is unspecified, scale original proportionally to height ratio. if (width == 0 && src_height > 0) { @@ -94,7 +103,7 @@ int WebPRescalerGetScaledDimensions(int src_width, int src_height, (int)(((uint64_t)src_height * width + src_width - 1) / src_width); } // Check if the overall dimensions still make sense. - if (width <= 0 || height <= 0) { + if (width <= 0 || height <= 0 || width > max_size || height > max_size) { return 0; } @@ -107,31 +116,34 @@ int WebPRescalerGetScaledDimensions(int src_width, int src_height, //------------------------------------------------------------------------------ // all-in-one calls -int WebPRescaleNeededLines(const WebPRescaler* const wrk, int max_num_lines) { - const int num_lines = (wrk->y_accum + wrk->y_sub - 1) / wrk->y_sub; +int WebPRescaleNeededLines(const WebPRescaler* const rescaler, + int max_num_lines) { + const int num_lines = + (rescaler->y_accum + rescaler->y_sub - 1) / rescaler->y_sub; return (num_lines > max_num_lines) ? max_num_lines : num_lines; } -int WebPRescalerImport(WebPRescaler* const wrk, int num_lines, +int WebPRescalerImport(WebPRescaler* const rescaler, int num_lines, const uint8_t* src, int src_stride) { int total_imported = 0; - while (total_imported < num_lines && !WebPRescalerHasPendingOutput(wrk)) { - if (wrk->y_expand) { - rescaler_t* const tmp = wrk->irow; - wrk->irow = wrk->frow; - wrk->frow = tmp; + while (total_imported < num_lines && + !WebPRescalerHasPendingOutput(rescaler)) { + if (rescaler->y_expand) { + rescaler_t* const tmp = rescaler->irow; + rescaler->irow = rescaler->frow; + rescaler->frow = tmp; } - WebPRescalerImportRow(wrk, src); - if (!wrk->y_expand) { // Accumulate the contribution of the new row. + WebPRescalerImportRow(rescaler, src); + if (!rescaler->y_expand) { // Accumulate the contribution of the new row. int x; - for (x = 0; x < wrk->num_channels * wrk->dst_width; ++x) { - wrk->irow[x] += wrk->frow[x]; + for (x = 0; x < rescaler->num_channels * rescaler->dst_width; ++x) { + rescaler->irow[x] += rescaler->frow[x]; } } - ++wrk->src_y; + ++rescaler->src_y; src += src_stride; ++total_imported; - wrk->y_accum -= wrk->y_sub; + rescaler->y_accum -= rescaler->y_sub; } return total_imported; } diff --git a/thirdparty/libwebp/src/utils/rescaler_utils.h b/thirdparty/libwebp/src/utils/rescaler_utils.h index ca41e42c4a..ef201ef86c 100644 --- a/thirdparty/libwebp/src/utils/rescaler_utils.h +++ b/thirdparty/libwebp/src/utils/rescaler_utils.h @@ -47,12 +47,13 @@ struct WebPRescaler { }; // Initialize a rescaler given scratch area 'work' and dimensions of src & dst. -void WebPRescalerInit(WebPRescaler* const rescaler, - int src_width, int src_height, - uint8_t* const dst, - int dst_width, int dst_height, int dst_stride, - int num_channels, - rescaler_t* const work); +// Returns false in case of error. +int WebPRescalerInit(WebPRescaler* const rescaler, + int src_width, int src_height, + uint8_t* const dst, + int dst_width, int dst_height, int dst_stride, + int num_channels, + rescaler_t* const work); // If either 'scaled_width' or 'scaled_height' (but not both) is 0 the value // will be calculated preserving the aspect ratio, otherwise the values are diff --git a/thirdparty/libwebp/src/utils/utils.c b/thirdparty/libwebp/src/utils/utils.c index 764f752b82..a7c3a70fef 100644 --- a/thirdparty/libwebp/src/utils/utils.c +++ b/thirdparty/libwebp/src/utils/utils.c @@ -23,7 +23,7 @@ // alloc/free etc) is printed. For debugging/tuning purpose only (it's slow, // and not multi-thread safe!). // An interesting alternative is valgrind's 'massif' tool: -// http://valgrind.org/docs/manual/ms-manual.html +// https://valgrind.org/docs/manual/ms-manual.html // Here is an example command line: /* valgrind --tool=massif --massif-out-file=massif.out \ --stacks=yes --alloc-fn=WebPSafeMalloc --alloc-fn=WebPSafeCalloc @@ -101,6 +101,9 @@ static void Increment(int* const v) { #if defined(MALLOC_LIMIT) { const char* const malloc_limit_str = getenv("MALLOC_LIMIT"); +#if MALLOC_LIMIT > 1 + mem_limit = (size_t)MALLOC_LIMIT; +#endif if (malloc_limit_str != NULL) { mem_limit = atoi(malloc_limit_str); } @@ -169,16 +172,16 @@ static int CheckSizeArgumentsOverflow(uint64_t nmemb, size_t size) { const uint64_t total_size = nmemb * size; if (nmemb == 0) return 1; if ((uint64_t)size > WEBP_MAX_ALLOCABLE_MEMORY / nmemb) return 0; - if (total_size != (size_t)total_size) return 0; + if (!CheckSizeOverflow(total_size)) return 0; #if defined(PRINT_MEM_INFO) && defined(MALLOC_FAIL_AT) if (countdown_to_fail > 0 && --countdown_to_fail == 0) { return 0; // fake fail! } #endif -#if defined(MALLOC_LIMIT) +#if defined(PRINT_MEM_INFO) && defined(MALLOC_LIMIT) if (mem_limit > 0) { const uint64_t new_total_mem = (uint64_t)total_mem + total_size; - if (new_total_mem != (size_t)new_total_mem || + if (!CheckSizeOverflow(new_total_mem) || new_total_mem > mem_limit) { return 0; // fake fail! } @@ -231,7 +234,7 @@ void WebPFree(void* ptr) { void WebPCopyPlane(const uint8_t* src, int src_stride, uint8_t* dst, int dst_stride, int width, int height) { assert(src != NULL && dst != NULL); - assert(src_stride >= width && dst_stride >= width); + assert(abs(src_stride) >= width && abs(dst_stride) >= width); while (height-- > 0) { memcpy(dst, src, width); src += src_stride; diff --git a/thirdparty/libwebp/src/utils/utils.h b/thirdparty/libwebp/src/utils/utils.h index 2a3ec92678..ef04f108fe 100644 --- a/thirdparty/libwebp/src/utils/utils.h +++ b/thirdparty/libwebp/src/utils/utils.h @@ -42,6 +42,10 @@ extern "C" { #endif #endif // WEBP_MAX_ALLOCABLE_MEMORY +static WEBP_INLINE int CheckSizeOverflow(uint64_t size) { + return size == (size_t)size; +} + // size-checking safe malloc/calloc: verify that the requested size is not too // large, or return NULL. You don't need to call these for constructs like // malloc(sizeof(foo)), but only if there's picture-dependent size involved @@ -107,24 +111,33 @@ static WEBP_INLINE void PutLE32(uint8_t* const data, uint32_t val) { PutLE16(data + 2, (int)(val >> 16)); } -// Returns (int)floor(log2(n)). n must be > 0. // use GNU builtins where available. #if defined(__GNUC__) && \ ((__GNUC__ == 3 && __GNUC_MINOR__ >= 4) || __GNUC__ >= 4) +// Returns (int)floor(log2(n)). n must be > 0. static WEBP_INLINE int BitsLog2Floor(uint32_t n) { return 31 ^ __builtin_clz(n); } +// counts the number of trailing zero +static WEBP_INLINE int BitsCtz(uint32_t n) { return __builtin_ctz(n); } #elif defined(_MSC_VER) && _MSC_VER > 1310 && \ (defined(_M_X64) || defined(_M_IX86)) #include <intrin.h> #pragma intrinsic(_BitScanReverse) +#pragma intrinsic(_BitScanForward) static WEBP_INLINE int BitsLog2Floor(uint32_t n) { - unsigned long first_set_bit; + unsigned long first_set_bit; // NOLINT (runtime/int) _BitScanReverse(&first_set_bit, n); return first_set_bit; } -#else // default: use the C-version. +static WEBP_INLINE int BitsCtz(uint32_t n) { + unsigned long first_set_bit; // NOLINT (runtime/int) + _BitScanForward(&first_set_bit, n); + return first_set_bit; +} +#else // default: use the (slow) C-version. +#define WEBP_HAVE_SLOW_CLZ_CTZ // signal that the Clz/Ctz function are slow // Returns 31 ^ clz(n) = log2(n). This is the default C-implementation, either // based on table or not. Can be used as fallback if clz() is not available. #define WEBP_NEED_LOG_TABLE_8BIT @@ -139,6 +152,15 @@ static WEBP_INLINE int WebPLog2FloorC(uint32_t n) { } static WEBP_INLINE int BitsLog2Floor(uint32_t n) { return WebPLog2FloorC(n); } + +static WEBP_INLINE int BitsCtz(uint32_t n) { + int i; + for (i = 0; i < 32; ++i, n >>= 1) { + if (n & 1) return i; + } + return 32; +} + #endif //------------------------------------------------------------------------------ |