third_party/libjpeg_turbo/jchuff.c - Issue 7554002: Updates libjpeg-turbo to 1.1.90 (r677)

Unified Diff: third_party/libjpeg_turbo/jchuff.c

Issue 7554002: Updates libjpeg-turbo to 1.1.90 (r677) (Closed) Base URL: svn://svn.chromium.org/chrome/trunk/deps/

Patch Set: '' Created 9 years, 5 months ago

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Index: third_party/libjpeg_turbo/jchuff.c

===================================================================

--- third_party/libjpeg_turbo/jchuff.c (revision 95020)

+++ third_party/libjpeg_turbo/jchuff.c (working copy)

@@ -2,6 +2,7 @@

* jchuff.c

* This file is part of the Independent JPEG Group's software.

* For conditions of distribution and use, see the accompanying README file.

@@ -14,34 +15,20 @@

* permanent JPEG objects only upon successful completion of an MCU.

-/* Modifications:

- *

- * This library is free software and may be redistributed and/or modified under

- * the terms of the wxWindows Library License, Version 3.1 or (at your option)

- * any later version. The full license is in the LICENSE.txt file included

- * with this distribution.

- *

- * This library is distributed in the hope that it will be useful,

- * but WITHOUT ANY WARRANTY; without even the implied warranty of

- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

- * wxWindows Library License for more details.

- */

#define JPEG_INTERNALS

#include "jinclude.h"

#include "jpeglib.h"

#include "jchuff.h" /* Declarations shared with jcphuff.c */

#include <limits.h>

-static unsigned char jpeg_first_bit_table[65536];

-int jpeg_first_bit_table_init=0;

+static unsigned char jpeg_nbits_table[65536];

+static int jpeg_nbits_table_init = 0;

#ifndef min

#define min(a,b) ((a)<(b)?(a):(b))

#endif

/* Expanded entropy encoder object for Huffman encoding.

* The savable_state subrecord contains fields that change within an MCU,

@@ -181,7 +168,6 @@

}

/* Initialize bit buffer to empty */

entropy->saved.put_buffer = 0;

entropy->saved.put_bits = 0;

@@ -285,13 +271,13 @@

dtbl->ehufsi[i] = huffsize[p];

}

- if(!jpeg_first_bit_table_init) {

+ if(!jpeg_nbits_table_init) {

for(i = 0; i < 65536; i++) {

- int bit = 0, val = i;

- while (val) {val >>= 1; bit++;}

- jpeg_first_bit_table[i] = bit;

+ int nbits = 0, temp = i;

+ while (temp) {temp >>= 1; nbits++;}

+ jpeg_nbits_table[i] = nbits;

}

- jpeg_first_bit_table_init = 1;

+ jpeg_nbits_table_init = 1;

}

@@ -325,170 +311,123 @@

/* Outputting bits to the file */

-/* Only the right 24 bits of put_buffer are used; the valid bits are

- * left-justified in this part. At most 16 bits can be passed to emit_bits

- * in one call, and we never retain more than 7 bits in put_buffer

- * between calls, so 24 bits are sufficient.

+/* These macros perform the same task as the emit_bits() function in the

+ * original libjpeg code. In addition to reducing overhead by explicitly

+ * inlining the code, additional performance is achieved by taking into

+ * account the size of the bit buffer and waiting until it is almost full

+ * before emptying it. This mostly benefits 64-bit platforms, since 6

+ * bytes can be stored in a 64-bit bit buffer before it has to be emptied.

-/***************************************************************/

-#define EMIT_BYTE() { \

- if (0xFF == (*buffer++ = (unsigned char)(put_buffer >> (put_bits -= 8)))) \

- *buffer++ = 0; \

+#define EMIT_BYTE() { \

+ JOCTET c; \

+ put_bits -= 8; \

+ c = (JOCTET)GETJOCTET(put_buffer >> put_bits); \

+ *buffer++ = c; \

+ if (c == 0xFF) /* need to stuff a zero byte? */ \

+ *buffer++ = 0; \

}

-/***************************************************************/

+#define PUT_BITS(code, size) { \

+ put_bits += size; \

+ put_buffer = (put_buffer << size) | code; \

-#define DUMP_BITS_(code, size) { \

- put_bits += size; \

- put_buffer = (put_buffer << size) | code; \

- if (put_bits > 7) \

- while(put_bits > 7) \

- EMIT_BYTE() \

- }

-/***************************************************************/

-#define CHECKBUF15() { \

- if (put_bits > 15) { \

- EMIT_BYTE() \

- } \

+#define CHECKBUF15() { \

+ if (put_bits > 15) { \

+ EMIT_BYTE() \

+ } \

}

-#define CHECKBUF47() { \

- if (put_bits > 47) { \

- EMIT_BYTE() \

- } \

+#define CHECKBUF31() { \

+ if (put_bits > 31) { \

+ EMIT_BYTE() \

+ } \

}

-#define CHECKBUF31() { \

- if (put_bits > 31) { \

- EMIT_BYTE() \

- } \

+#define CHECKBUF47() { \

+ if (put_bits > 47) { \

+ EMIT_BYTE() \

+ } \

}

-/***************************************************************/

-#define DUMP_BITS_NOCHECK(code, size) { \

- put_bits += size; \

- put_buffer = (put_buffer << size) | code; \

- }

#if __WORDSIZE==64 || defined(_WIN64)

-#define DUMP_BITS(code, size) { \

- CHECKBUF47() \

- put_bits += size; \

- put_buffer = (put_buffer << size) | code; \

+#define EMIT_BITS(code, size) { \

+ CHECKBUF47() \

+ PUT_BITS(code, size) \

+#define EMIT_CODE(code, size) { \

+ temp2 &= (((INT32) 1)<<nbits) - 1; \

+ CHECKBUF31() \

+ PUT_BITS(code, size) \

+ PUT_BITS(temp2, nbits) \

}

#else

-#define DUMP_BITS(code, size) { \

- put_bits += size; \

- put_buffer = (put_buffer << size) | code; \

- CHECKBUF15() \

- }

+#define EMIT_BITS(code, size) { \

+ PUT_BITS(code, size) \

+ CHECKBUF15() \

-#endif

-/***************************************************************/

-#define DUMP_SINGLE_VALUE(ht, codevalue) { \

- size = ht->ehufsi[codevalue]; \

- code = ht->ehufco[codevalue]; \

- \

- DUMP_BITS(code, size) \

+#define EMIT_CODE(code, size) { \

+ temp2 &= (((INT32) 1)<<nbits) - 1; \

+ PUT_BITS(code, size) \

+ CHECKBUF15() \

+ PUT_BITS(temp2, nbits) \

+ CHECKBUF15() \

}

-/***************************************************************/

-#define DUMP_VALUE_SLOW(ht, codevalue, t, nbits) { \

- size = ht->ehufsi[codevalue]; \

- code = ht->ehufco[codevalue]; \

- t &= ~(-1 << nbits); \

- DUMP_BITS_NOCHECK(code, size) \

- CHECKBUF15() \

- DUMP_BITS_NOCHECK(t, nbits) \

- CHECKBUF15() \

- }

-int _max=0;

-#if __WORDSIZE==64 || defined(_WIN64)

-#define DUMP_VALUE(ht, codevalue, t, nbits) { \

- size = ht->ehufsi[codevalue]; \

- code = ht->ehufco[codevalue]; \

- t &= ~(-1 << nbits); \

- CHECKBUF31() \

- DUMP_BITS_NOCHECK(code, size) \

- DUMP_BITS_NOCHECK(t, nbits) \

- }

-#else

-#define DUMP_VALUE(ht, codevalue, t, nbits) { \

- size = ht->ehufsi[codevalue]; \

- code = ht->ehufco[codevalue]; \

- t &= ~(-1 << nbits); \

- DUMP_BITS_NOCHECK(code, size) \

- CHECKBUF15() \

- DUMP_BITS_NOCHECK(t, nbits) \

- CHECKBUF15() \

- }

#endif

-/***************************************************************/

#define BUFSIZE (DCTSIZE2 * 2)

-#define LOAD_BUFFER() { \

- if (state->free_in_buffer < BUFSIZE) { \

- localbuf = 1; \

- buffer = _buffer; \

- } \

- else buffer = state->next_output_byte; \

+#define LOAD_BUFFER() { \

+ if (state->free_in_buffer < BUFSIZE) { \

+ localbuf = 1; \

+ buffer = _buffer; \

+ } \

+ else buffer = state->next_output_byte; \

}

-#define STORE_BUFFER() { \

- if (localbuf) { \

- bytes = buffer - _buffer; \

- buffer = _buffer; \

- while (bytes > 0) { \

- bytestocopy = min(bytes, state->free_in_buffer); \

- MEMCOPY(state->next_output_byte, buffer, bytestocopy); \

- state->next_output_byte += bytestocopy; \

- buffer += bytestocopy; \

- state->free_in_buffer -= bytestocopy; \

- if (state->free_in_buffer == 0) \

- if (! dump_buffer(state)) return FALSE; \

- bytes -= bytestocopy; \

- } \

- else { \

- state->free_in_buffer -= (buffer - state->next_output_byte); \

- state->next_output_byte = buffer; \

- } \

+#define STORE_BUFFER() { \

+ if (localbuf) { \

+ bytes = buffer - _buffer; \

+ buffer = _buffer; \

+ while (bytes > 0) { \

+ bytestocopy = min(bytes, state->free_in_buffer); \

+ MEMCOPY(state->next_output_byte, buffer, bytestocopy); \

+ state->next_output_byte += bytestocopy; \

+ buffer += bytestocopy; \

+ state->free_in_buffer -= bytestocopy; \

+ if (state->free_in_buffer == 0) \

+ if (! dump_buffer(state)) return FALSE; \

+ bytes -= bytestocopy; \

+ } \

+ else { \

+ state->free_in_buffer -= (buffer - state->next_output_byte); \

+ state->next_output_byte = buffer; \

+ } \

}

-/***************************************************************/

LOCAL(boolean)

flush_bits (working_state * state)

{

- unsigned char _buffer[BUFSIZE], *buffer;

+ JOCTET _buffer[BUFSIZE], *buffer;

size_t put_buffer; int put_bits;

size_t bytes, bytestocopy; int localbuf = 0;

@@ -496,7 +435,9 @@

put_bits = state->cur.put_bits;

LOAD_BUFFER()

- DUMP_BITS_(0x7F, 7)

+ /* fill any partial byte with ones */

+ PUT_BITS(0x7F, 7)

+ while (put_bits >= 8) EMIT_BYTE()

state->cur.put_buffer = 0; /* and reset bit-buffer to empty */

state->cur.put_bits = 0;

@@ -505,16 +446,17 @@

return TRUE;

}

/* Encode a single block's worth of coefficients */

LOCAL(boolean)

encode_one_block (working_state * state, JCOEFPTR block, int last_dc_val,

c_derived_tbl *dctbl, c_derived_tbl *actbl)

{

- int temp, temp2;

+ int temp, temp2, temp3;

int nbits;

- int r, sflag, size, code;

- unsigned char _buffer[BUFSIZE], *buffer;

+ int r, code, size;

+ JOCTET _buffer[BUFSIZE], *buffer;

size_t put_buffer; int put_bits;

int code_0xf0 = actbl->ehufco[0xf0], size_0xf0 = actbl->ehufsi[0xf0];

size_t bytes, bytestocopy; int localbuf = 0;

@@ -527,50 +469,88 @@

temp = temp2 = block[0] - last_dc_val;

- sflag = temp >> 31;

- temp -= ((temp + temp) & sflag);

- temp2 += sflag;

- nbits = jpeg_first_bit_table[temp];

- DUMP_VALUE_SLOW(dctbl, nbits, temp2, nbits)

+ /* This is a well-known technique for obtaining the absolute value without a

+ * branch. It is derived from an assembly language technique presented in

+ * Agner Fog.

+ */

+ temp3 = temp >> (CHAR_BIT * sizeof(int) - 1);

+ temp ^= temp3;

+ temp -= temp3;

+ /* For a negative input, want temp2 = bitwise complement of abs(input) */

+ /* This code assumes we are on a two's complement machine */

+ temp2 += temp3;

+ /* Find the number of bits needed for the magnitude of the coefficient */

+ nbits = jpeg_nbits_table[temp];

+ /* Emit the Huffman-coded symbol for the number of bits */

+ code = dctbl->ehufco[nbits];

+ size = dctbl->ehufsi[nbits];

+ PUT_BITS(code, size)

+ CHECKBUF15()

+ /* Mask off any extra bits in code */

+ temp2 &= (((INT32) 1)<<nbits) - 1;

+ /* Emit that number of bits of the value, if positive, */

+ /* or the complement of its magnitude, if negative. */

+ PUT_BITS(temp2, nbits)

+ CHECKBUF15()

/* Encode the AC coefficients per section F.1.2.2 */

r = 0; /* r = run length of zeros */

-#define innerloop(order) { \

- temp2 = *(JCOEF*)((unsigned char*)block + order); \

- if(temp2 == 0) r++; \

- else { \

- temp = (JCOEF)temp2; \

- sflag = temp >> 31; \

- temp = (temp ^ sflag) - sflag; \

- temp2 += sflag; \

- nbits = jpeg_first_bit_table[temp]; \

- for(; r > 15; r -= 16) DUMP_BITS(code_0xf0, size_0xf0) \

- sflag = (r << 4) + nbits; \

- DUMP_VALUE(actbl, sflag, temp2, nbits) \

+/* Manually unroll the k loop to eliminate the counter variable. This

+ * improves performance greatly on systems with a limited number of

+ * registers (such as x86.)

+ */

+#define kloop(jpeg_natural_order_of_k) { \

+ if ((temp = block[jpeg_natural_order_of_k]) == 0) { \

+ r++; \

+ } else { \

+ temp2 = temp; \

+ /* Branch-less absolute value, bitwise complement, etc., same as above */ \

+ temp3 = temp >> (CHAR_BIT * sizeof(int) - 1); \

+ temp ^= temp3; \

+ temp -= temp3; \

+ temp2 += temp3; \

+ nbits = jpeg_nbits_table[temp]; \

+ /* if run length > 15, must emit special run-length-16 codes (0xF0) */ \

+ while (r > 15) { \

+ EMIT_BITS(code_0xf0, size_0xf0) \

+ r -= 16; \

+ } \

+ /* Emit Huffman symbol for run length / number of bits */ \

+ temp3 = (r << 4) + nbits; \

+ code = actbl->ehufco[temp3]; \

+ size = actbl->ehufsi[temp3]; \

+ EMIT_CODE(code, size) \

r = 0; \

- }}

+ } \

- innerloop(2*1); innerloop(2*8); innerloop(2*16); innerloop(2*9);

- innerloop(2*2); innerloop(2*3); innerloop(2*10); innerloop(2*17);

- innerloop(2*24); innerloop(2*32); innerloop(2*25); innerloop(2*18);

- innerloop(2*11); innerloop(2*4); innerloop(2*5); innerloop(2*12);

- innerloop(2*19); innerloop(2*26); innerloop(2*33); innerloop(2*40);

- innerloop(2*48); innerloop(2*41); innerloop(2*34); innerloop(2*27);

- innerloop(2*20); innerloop(2*13); innerloop(2*6); innerloop(2*7);

- innerloop(2*14); innerloop(2*21); innerloop(2*28); innerloop(2*35);

- innerloop(2*42); innerloop(2*49); innerloop(2*56); innerloop(2*57);

- innerloop(2*50); innerloop(2*43); innerloop(2*36); innerloop(2*29);

- innerloop(2*22); innerloop(2*15); innerloop(2*23); innerloop(2*30);

- innerloop(2*37); innerloop(2*44); innerloop(2*51); innerloop(2*58);

- innerloop(2*59); innerloop(2*52); innerloop(2*45); innerloop(2*38);

- innerloop(2*31); innerloop(2*39); innerloop(2*46); innerloop(2*53);

- innerloop(2*60); innerloop(2*61); innerloop(2*54); innerloop(2*47);

- innerloop(2*55); innerloop(2*62); innerloop(2*63);

+ /* One iteration for each value in jpeg_natural_order[] */

+ kloop(1); kloop(8); kloop(16); kloop(9); kloop(2); kloop(3);

+ kloop(10); kloop(17); kloop(24); kloop(32); kloop(25); kloop(18);

+ kloop(11); kloop(4); kloop(5); kloop(12); kloop(19); kloop(26);

+ kloop(33); kloop(40); kloop(48); kloop(41); kloop(34); kloop(27);

+ kloop(20); kloop(13); kloop(6); kloop(7); kloop(14); kloop(21);

+ kloop(28); kloop(35); kloop(42); kloop(49); kloop(56); kloop(57);

+ kloop(50); kloop(43); kloop(36); kloop(29); kloop(22); kloop(15);

+ kloop(23); kloop(30); kloop(37); kloop(44); kloop(51); kloop(58);

+ kloop(59); kloop(52); kloop(45); kloop(38); kloop(31); kloop(39);

+ kloop(46); kloop(53); kloop(60); kloop(61); kloop(54); kloop(47);

+ kloop(55); kloop(62); kloop(63);

/* If the last coef(s) were zero, emit an end-of-block code */

- if (r > 0) DUMP_SINGLE_VALUE(actbl, 0x0)

+ if (r > 0) {

+ code = actbl->ehufco[0];

+ size = actbl->ehufsi[0];

+ EMIT_BITS(code, size)

+ }

state->cur.put_buffer = put_buffer;

state->cur.put_bits = put_bits;

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