зеркало из https://github.com/mozilla/gecko-dev.git
643 строки
19 KiB
C
643 строки
19 KiB
C
/*
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* jcdctmgr.c
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*
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* Copyright (C) 1994-1996, Thomas G. Lane.
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* Copyright (C) 1999-2006, MIYASAKA Masaru.
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* Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
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* Copyright (C) 2011 D. R. Commander
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* This file is part of the Independent JPEG Group's software.
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* For conditions of distribution and use, see the accompanying README file.
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*
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* This file contains the forward-DCT management logic.
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* This code selects a particular DCT implementation to be used,
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* and it performs related housekeeping chores including coefficient
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* quantization.
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*/
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#define JPEG_INTERNALS
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#include "jinclude.h"
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#include "jpeglib.h"
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#include "jdct.h" /* Private declarations for DCT subsystem */
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#include "jsimddct.h"
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/* Private subobject for this module */
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typedef JMETHOD(void, forward_DCT_method_ptr, (DCTELEM * data));
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typedef JMETHOD(void, float_DCT_method_ptr, (FAST_FLOAT * data));
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typedef JMETHOD(void, convsamp_method_ptr,
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(JSAMPARRAY sample_data, JDIMENSION start_col,
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DCTELEM * workspace));
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typedef JMETHOD(void, float_convsamp_method_ptr,
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(JSAMPARRAY sample_data, JDIMENSION start_col,
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FAST_FLOAT *workspace));
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typedef JMETHOD(void, quantize_method_ptr,
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(JCOEFPTR coef_block, DCTELEM * divisors,
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DCTELEM * workspace));
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typedef JMETHOD(void, float_quantize_method_ptr,
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(JCOEFPTR coef_block, FAST_FLOAT * divisors,
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FAST_FLOAT * workspace));
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METHODDEF(void) quantize (JCOEFPTR, DCTELEM *, DCTELEM *);
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typedef struct {
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struct jpeg_forward_dct pub; /* public fields */
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/* Pointer to the DCT routine actually in use */
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forward_DCT_method_ptr dct;
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convsamp_method_ptr convsamp;
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quantize_method_ptr quantize;
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/* The actual post-DCT divisors --- not identical to the quant table
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* entries, because of scaling (especially for an unnormalized DCT).
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* Each table is given in normal array order.
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*/
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DCTELEM * divisors[NUM_QUANT_TBLS];
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/* work area for FDCT subroutine */
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DCTELEM * workspace;
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#ifdef DCT_FLOAT_SUPPORTED
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/* Same as above for the floating-point case. */
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float_DCT_method_ptr float_dct;
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float_convsamp_method_ptr float_convsamp;
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float_quantize_method_ptr float_quantize;
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FAST_FLOAT * float_divisors[NUM_QUANT_TBLS];
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FAST_FLOAT * float_workspace;
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#endif
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} my_fdct_controller;
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typedef my_fdct_controller * my_fdct_ptr;
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/*
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* Find the highest bit in an integer through binary search.
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*/
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LOCAL(int)
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flss (UINT16 val)
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{
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int bit;
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bit = 16;
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if (!val)
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return 0;
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if (!(val & 0xff00)) {
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bit -= 8;
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val <<= 8;
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}
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if (!(val & 0xf000)) {
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bit -= 4;
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val <<= 4;
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}
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if (!(val & 0xc000)) {
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bit -= 2;
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val <<= 2;
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}
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if (!(val & 0x8000)) {
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bit -= 1;
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val <<= 1;
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}
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return bit;
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}
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/*
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* Compute values to do a division using reciprocal.
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*
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* This implementation is based on an algorithm described in
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* "How to optimize for the Pentium family of microprocessors"
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* (http://www.agner.org/assem/).
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* More information about the basic algorithm can be found in
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* the paper "Integer Division Using Reciprocals" by Robert Alverson.
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*
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* The basic idea is to replace x/d by x * d^-1. In order to store
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* d^-1 with enough precision we shift it left a few places. It turns
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* out that this algoright gives just enough precision, and also fits
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* into DCTELEM:
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*
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* b = (the number of significant bits in divisor) - 1
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* r = (word size) + b
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* f = 2^r / divisor
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*
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* f will not be an integer for most cases, so we need to compensate
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* for the rounding error introduced:
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*
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* no fractional part:
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*
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* result = input >> r
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*
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* fractional part of f < 0.5:
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*
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* round f down to nearest integer
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* result = ((input + 1) * f) >> r
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*
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* fractional part of f > 0.5:
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*
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* round f up to nearest integer
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* result = (input * f) >> r
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*
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* This is the original algorithm that gives truncated results. But we
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* want properly rounded results, so we replace "input" with
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* "input + divisor/2".
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*
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* In order to allow SIMD implementations we also tweak the values to
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* allow the same calculation to be made at all times:
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*
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* dctbl[0] = f rounded to nearest integer
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* dctbl[1] = divisor / 2 (+ 1 if fractional part of f < 0.5)
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* dctbl[2] = 1 << ((word size) * 2 - r)
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* dctbl[3] = r - (word size)
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*
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* dctbl[2] is for stupid instruction sets where the shift operation
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* isn't member wise (e.g. MMX).
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*
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* The reason dctbl[2] and dctbl[3] reduce the shift with (word size)
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* is that most SIMD implementations have a "multiply and store top
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* half" operation.
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*
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* Lastly, we store each of the values in their own table instead
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* of in a consecutive manner, yet again in order to allow SIMD
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* routines.
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*/
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LOCAL(int)
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compute_reciprocal (UINT16 divisor, DCTELEM * dtbl)
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{
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UDCTELEM2 fq, fr;
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UDCTELEM c;
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int b, r;
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b = flss(divisor) - 1;
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r = sizeof(DCTELEM) * 8 + b;
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fq = ((UDCTELEM2)1 << r) / divisor;
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fr = ((UDCTELEM2)1 << r) % divisor;
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c = divisor / 2; /* for rounding */
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if (fr == 0) { /* divisor is power of two */
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/* fq will be one bit too large to fit in DCTELEM, so adjust */
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fq >>= 1;
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r--;
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} else if (fr <= (divisor / 2)) { /* fractional part is < 0.5 */
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c++;
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} else { /* fractional part is > 0.5 */
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fq++;
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}
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dtbl[DCTSIZE2 * 0] = (DCTELEM) fq; /* reciprocal */
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dtbl[DCTSIZE2 * 1] = (DCTELEM) c; /* correction + roundfactor */
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dtbl[DCTSIZE2 * 2] = (DCTELEM) (1 << (sizeof(DCTELEM)*8*2 - r)); /* scale */
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dtbl[DCTSIZE2 * 3] = (DCTELEM) r - sizeof(DCTELEM)*8; /* shift */
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if(r <= 16) return 0;
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else return 1;
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}
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/*
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* Initialize for a processing pass.
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* Verify that all referenced Q-tables are present, and set up
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* the divisor table for each one.
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* In the current implementation, DCT of all components is done during
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* the first pass, even if only some components will be output in the
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* first scan. Hence all components should be examined here.
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*/
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METHODDEF(void)
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start_pass_fdctmgr (j_compress_ptr cinfo)
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{
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my_fdct_ptr fdct = (my_fdct_ptr) cinfo->fdct;
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int ci, qtblno, i;
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jpeg_component_info *compptr;
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JQUANT_TBL * qtbl;
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DCTELEM * dtbl;
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for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
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ci++, compptr++) {
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qtblno = compptr->quant_tbl_no;
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/* Make sure specified quantization table is present */
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if (qtblno < 0 || qtblno >= NUM_QUANT_TBLS ||
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cinfo->quant_tbl_ptrs[qtblno] == NULL)
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ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, qtblno);
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qtbl = cinfo->quant_tbl_ptrs[qtblno];
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/* Compute divisors for this quant table */
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/* We may do this more than once for same table, but it's not a big deal */
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switch (cinfo->dct_method) {
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#ifdef DCT_ISLOW_SUPPORTED
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case JDCT_ISLOW:
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/* For LL&M IDCT method, divisors are equal to raw quantization
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* coefficients multiplied by 8 (to counteract scaling).
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*/
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if (fdct->divisors[qtblno] == NULL) {
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fdct->divisors[qtblno] = (DCTELEM *)
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(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
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(DCTSIZE2 * 4) * SIZEOF(DCTELEM));
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}
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dtbl = fdct->divisors[qtblno];
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for (i = 0; i < DCTSIZE2; i++) {
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if(!compute_reciprocal(qtbl->quantval[i] << 3, &dtbl[i])
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&& fdct->quantize == jsimd_quantize)
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fdct->quantize = quantize;
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}
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break;
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#endif
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#ifdef DCT_IFAST_SUPPORTED
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case JDCT_IFAST:
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{
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/* For AA&N IDCT method, divisors are equal to quantization
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* coefficients scaled by scalefactor[row]*scalefactor[col], where
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* scalefactor[0] = 1
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* scalefactor[k] = cos(k*PI/16) * sqrt(2) for k=1..7
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* We apply a further scale factor of 8.
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*/
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#define CONST_BITS 14
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static const INT16 aanscales[DCTSIZE2] = {
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/* precomputed values scaled up by 14 bits */
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16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520,
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22725, 31521, 29692, 26722, 22725, 17855, 12299, 6270,
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21407, 29692, 27969, 25172, 21407, 16819, 11585, 5906,
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19266, 26722, 25172, 22654, 19266, 15137, 10426, 5315,
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16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520,
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12873, 17855, 16819, 15137, 12873, 10114, 6967, 3552,
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8867, 12299, 11585, 10426, 8867, 6967, 4799, 2446,
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4520, 6270, 5906, 5315, 4520, 3552, 2446, 1247
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};
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SHIFT_TEMPS
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if (fdct->divisors[qtblno] == NULL) {
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fdct->divisors[qtblno] = (DCTELEM *)
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(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
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(DCTSIZE2 * 4) * SIZEOF(DCTELEM));
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}
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dtbl = fdct->divisors[qtblno];
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for (i = 0; i < DCTSIZE2; i++) {
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if(!compute_reciprocal(
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DESCALE(MULTIPLY16V16((INT32) qtbl->quantval[i],
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(INT32) aanscales[i]),
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CONST_BITS-3), &dtbl[i])
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&& fdct->quantize == jsimd_quantize)
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fdct->quantize = quantize;
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}
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}
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break;
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#endif
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#ifdef DCT_FLOAT_SUPPORTED
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case JDCT_FLOAT:
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{
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/* For float AA&N IDCT method, divisors are equal to quantization
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* coefficients scaled by scalefactor[row]*scalefactor[col], where
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* scalefactor[0] = 1
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* scalefactor[k] = cos(k*PI/16) * sqrt(2) for k=1..7
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* We apply a further scale factor of 8.
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* What's actually stored is 1/divisor so that the inner loop can
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* use a multiplication rather than a division.
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*/
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FAST_FLOAT * fdtbl;
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int row, col;
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static const double aanscalefactor[DCTSIZE] = {
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1.0, 1.387039845, 1.306562965, 1.175875602,
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1.0, 0.785694958, 0.541196100, 0.275899379
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};
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if (fdct->float_divisors[qtblno] == NULL) {
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fdct->float_divisors[qtblno] = (FAST_FLOAT *)
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(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
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DCTSIZE2 * SIZEOF(FAST_FLOAT));
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}
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fdtbl = fdct->float_divisors[qtblno];
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i = 0;
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for (row = 0; row < DCTSIZE; row++) {
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for (col = 0; col < DCTSIZE; col++) {
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fdtbl[i] = (FAST_FLOAT)
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(1.0 / (((double) qtbl->quantval[i] *
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aanscalefactor[row] * aanscalefactor[col] * 8.0)));
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i++;
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}
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}
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}
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break;
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#endif
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default:
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ERREXIT(cinfo, JERR_NOT_COMPILED);
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break;
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}
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}
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}
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/*
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* Load data into workspace, applying unsigned->signed conversion.
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*/
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METHODDEF(void)
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convsamp (JSAMPARRAY sample_data, JDIMENSION start_col, DCTELEM * workspace)
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{
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register DCTELEM *workspaceptr;
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register JSAMPROW elemptr;
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register int elemr;
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workspaceptr = workspace;
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for (elemr = 0; elemr < DCTSIZE; elemr++) {
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elemptr = sample_data[elemr] + start_col;
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#if DCTSIZE == 8 /* unroll the inner loop */
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*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
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*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
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*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
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*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
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*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
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*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
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*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
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*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
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#else
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{
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register int elemc;
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for (elemc = DCTSIZE; elemc > 0; elemc--)
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*workspaceptr++ = GETJSAMPLE(*elemptr++) - CENTERJSAMPLE;
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}
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#endif
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}
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}
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/*
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* Quantize/descale the coefficients, and store into coef_blocks[].
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*/
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METHODDEF(void)
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quantize (JCOEFPTR coef_block, DCTELEM * divisors, DCTELEM * workspace)
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{
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int i;
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DCTELEM temp;
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UDCTELEM recip, corr, shift;
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UDCTELEM2 product;
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JCOEFPTR output_ptr = coef_block;
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for (i = 0; i < DCTSIZE2; i++) {
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temp = workspace[i];
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recip = divisors[i + DCTSIZE2 * 0];
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corr = divisors[i + DCTSIZE2 * 1];
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shift = divisors[i + DCTSIZE2 * 3];
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if (temp < 0) {
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temp = -temp;
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product = (UDCTELEM2)(temp + corr) * recip;
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product >>= shift + sizeof(DCTELEM)*8;
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temp = product;
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temp = -temp;
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} else {
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product = (UDCTELEM2)(temp + corr) * recip;
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product >>= shift + sizeof(DCTELEM)*8;
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temp = product;
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}
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output_ptr[i] = (JCOEF) temp;
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}
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}
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/*
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* Perform forward DCT on one or more blocks of a component.
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*
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* The input samples are taken from the sample_data[] array starting at
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* position start_row/start_col, and moving to the right for any additional
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* blocks. The quantized coefficients are returned in coef_blocks[].
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*/
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METHODDEF(void)
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forward_DCT (j_compress_ptr cinfo, jpeg_component_info * compptr,
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JSAMPARRAY sample_data, JBLOCKROW coef_blocks,
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JDIMENSION start_row, JDIMENSION start_col,
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JDIMENSION num_blocks)
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/* This version is used for integer DCT implementations. */
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{
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/* This routine is heavily used, so it's worth coding it tightly. */
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my_fdct_ptr fdct = (my_fdct_ptr) cinfo->fdct;
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DCTELEM * divisors = fdct->divisors[compptr->quant_tbl_no];
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DCTELEM * workspace;
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JDIMENSION bi;
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/* Make sure the compiler doesn't look up these every pass */
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forward_DCT_method_ptr do_dct = fdct->dct;
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convsamp_method_ptr do_convsamp = fdct->convsamp;
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quantize_method_ptr do_quantize = fdct->quantize;
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workspace = fdct->workspace;
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sample_data += start_row; /* fold in the vertical offset once */
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for (bi = 0; bi < num_blocks; bi++, start_col += DCTSIZE) {
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/* Load data into workspace, applying unsigned->signed conversion */
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(*do_convsamp) (sample_data, start_col, workspace);
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/* Perform the DCT */
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(*do_dct) (workspace);
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/* Quantize/descale the coefficients, and store into coef_blocks[] */
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(*do_quantize) (coef_blocks[bi], divisors, workspace);
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}
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}
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#ifdef DCT_FLOAT_SUPPORTED
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METHODDEF(void)
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convsamp_float (JSAMPARRAY sample_data, JDIMENSION start_col, FAST_FLOAT * workspace)
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{
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register FAST_FLOAT *workspaceptr;
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register JSAMPROW elemptr;
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register int elemr;
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workspaceptr = workspace;
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for (elemr = 0; elemr < DCTSIZE; elemr++) {
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elemptr = sample_data[elemr] + start_col;
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#if DCTSIZE == 8 /* unroll the inner loop */
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*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
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*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
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*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
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*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
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*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
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*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
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*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
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*workspaceptr++ = (FAST_FLOAT)(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
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#else
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{
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register int elemc;
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for (elemc = DCTSIZE; elemc > 0; elemc--)
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*workspaceptr++ = (FAST_FLOAT)
|
|
(GETJSAMPLE(*elemptr++) - CENTERJSAMPLE);
|
|
}
|
|
#endif
|
|
}
|
|
}
|
|
|
|
|
|
METHODDEF(void)
|
|
quantize_float (JCOEFPTR coef_block, FAST_FLOAT * divisors, FAST_FLOAT * workspace)
|
|
{
|
|
register FAST_FLOAT temp;
|
|
register int i;
|
|
register JCOEFPTR output_ptr = coef_block;
|
|
|
|
for (i = 0; i < DCTSIZE2; i++) {
|
|
/* Apply the quantization and scaling factor */
|
|
temp = workspace[i] * divisors[i];
|
|
|
|
/* Round to nearest integer.
|
|
* Since C does not specify the direction of rounding for negative
|
|
* quotients, we have to force the dividend positive for portability.
|
|
* The maximum coefficient size is +-16K (for 12-bit data), so this
|
|
* code should work for either 16-bit or 32-bit ints.
|
|
*/
|
|
output_ptr[i] = (JCOEF) ((int) (temp + (FAST_FLOAT) 16384.5) - 16384);
|
|
}
|
|
}
|
|
|
|
|
|
METHODDEF(void)
|
|
forward_DCT_float (j_compress_ptr cinfo, jpeg_component_info * compptr,
|
|
JSAMPARRAY sample_data, JBLOCKROW coef_blocks,
|
|
JDIMENSION start_row, JDIMENSION start_col,
|
|
JDIMENSION num_blocks)
|
|
/* This version is used for floating-point DCT implementations. */
|
|
{
|
|
/* This routine is heavily used, so it's worth coding it tightly. */
|
|
my_fdct_ptr fdct = (my_fdct_ptr) cinfo->fdct;
|
|
FAST_FLOAT * divisors = fdct->float_divisors[compptr->quant_tbl_no];
|
|
FAST_FLOAT * workspace;
|
|
JDIMENSION bi;
|
|
|
|
|
|
/* Make sure the compiler doesn't look up these every pass */
|
|
float_DCT_method_ptr do_dct = fdct->float_dct;
|
|
float_convsamp_method_ptr do_convsamp = fdct->float_convsamp;
|
|
float_quantize_method_ptr do_quantize = fdct->float_quantize;
|
|
workspace = fdct->float_workspace;
|
|
|
|
sample_data += start_row; /* fold in the vertical offset once */
|
|
|
|
for (bi = 0; bi < num_blocks; bi++, start_col += DCTSIZE) {
|
|
/* Load data into workspace, applying unsigned->signed conversion */
|
|
(*do_convsamp) (sample_data, start_col, workspace);
|
|
|
|
/* Perform the DCT */
|
|
(*do_dct) (workspace);
|
|
|
|
/* Quantize/descale the coefficients, and store into coef_blocks[] */
|
|
(*do_quantize) (coef_blocks[bi], divisors, workspace);
|
|
}
|
|
}
|
|
|
|
#endif /* DCT_FLOAT_SUPPORTED */
|
|
|
|
|
|
/*
|
|
* Initialize FDCT manager.
|
|
*/
|
|
|
|
GLOBAL(void)
|
|
jinit_forward_dct (j_compress_ptr cinfo)
|
|
{
|
|
my_fdct_ptr fdct;
|
|
int i;
|
|
|
|
fdct = (my_fdct_ptr)
|
|
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
|
|
SIZEOF(my_fdct_controller));
|
|
cinfo->fdct = (struct jpeg_forward_dct *) fdct;
|
|
fdct->pub.start_pass = start_pass_fdctmgr;
|
|
|
|
/* First determine the DCT... */
|
|
switch (cinfo->dct_method) {
|
|
#ifdef DCT_ISLOW_SUPPORTED
|
|
case JDCT_ISLOW:
|
|
fdct->pub.forward_DCT = forward_DCT;
|
|
if (jsimd_can_fdct_islow())
|
|
fdct->dct = jsimd_fdct_islow;
|
|
else
|
|
fdct->dct = jpeg_fdct_islow;
|
|
break;
|
|
#endif
|
|
#ifdef DCT_IFAST_SUPPORTED
|
|
case JDCT_IFAST:
|
|
fdct->pub.forward_DCT = forward_DCT;
|
|
if (jsimd_can_fdct_ifast())
|
|
fdct->dct = jsimd_fdct_ifast;
|
|
else
|
|
fdct->dct = jpeg_fdct_ifast;
|
|
break;
|
|
#endif
|
|
#ifdef DCT_FLOAT_SUPPORTED
|
|
case JDCT_FLOAT:
|
|
fdct->pub.forward_DCT = forward_DCT_float;
|
|
if (jsimd_can_fdct_float())
|
|
fdct->float_dct = jsimd_fdct_float;
|
|
else
|
|
fdct->float_dct = jpeg_fdct_float;
|
|
break;
|
|
#endif
|
|
default:
|
|
ERREXIT(cinfo, JERR_NOT_COMPILED);
|
|
break;
|
|
}
|
|
|
|
/* ...then the supporting stages. */
|
|
switch (cinfo->dct_method) {
|
|
#ifdef DCT_ISLOW_SUPPORTED
|
|
case JDCT_ISLOW:
|
|
#endif
|
|
#ifdef DCT_IFAST_SUPPORTED
|
|
case JDCT_IFAST:
|
|
#endif
|
|
#if defined(DCT_ISLOW_SUPPORTED) || defined(DCT_IFAST_SUPPORTED)
|
|
if (jsimd_can_convsamp())
|
|
fdct->convsamp = jsimd_convsamp;
|
|
else
|
|
fdct->convsamp = convsamp;
|
|
if (jsimd_can_quantize())
|
|
fdct->quantize = jsimd_quantize;
|
|
else
|
|
fdct->quantize = quantize;
|
|
break;
|
|
#endif
|
|
#ifdef DCT_FLOAT_SUPPORTED
|
|
case JDCT_FLOAT:
|
|
if (jsimd_can_convsamp_float())
|
|
fdct->float_convsamp = jsimd_convsamp_float;
|
|
else
|
|
fdct->float_convsamp = convsamp_float;
|
|
if (jsimd_can_quantize_float())
|
|
fdct->float_quantize = jsimd_quantize_float;
|
|
else
|
|
fdct->float_quantize = quantize_float;
|
|
break;
|
|
#endif
|
|
default:
|
|
ERREXIT(cinfo, JERR_NOT_COMPILED);
|
|
break;
|
|
}
|
|
|
|
/* Allocate workspace memory */
|
|
#ifdef DCT_FLOAT_SUPPORTED
|
|
if (cinfo->dct_method == JDCT_FLOAT)
|
|
fdct->float_workspace = (FAST_FLOAT *)
|
|
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
|
|
SIZEOF(FAST_FLOAT) * DCTSIZE2);
|
|
else
|
|
#endif
|
|
fdct->workspace = (DCTELEM *)
|
|
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
|
|
SIZEOF(DCTELEM) * DCTSIZE2);
|
|
|
|
/* Mark divisor tables unallocated */
|
|
for (i = 0; i < NUM_QUANT_TBLS; i++) {
|
|
fdct->divisors[i] = NULL;
|
|
#ifdef DCT_FLOAT_SUPPORTED
|
|
fdct->float_divisors[i] = NULL;
|
|
#endif
|
|
}
|
|
}
|