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authorLoren Merritt <lorenm@u.washington.edu>2008-07-13 15:03:58 +0000
committerLoren Merritt <lorenm@u.washington.edu>2008-07-13 15:03:58 +0000
commitb9fa32082c71013e90eab9e9997967d2939cf4a6 (patch)
tree83edd135988c73a75b017fbd12396e156de5e0a4 /libavcodec
parenteb2cd99c73df74cba8ce0173f9ee2b70313adaa6 (diff)
downloadffmpeg-b9fa32082c71013e90eab9e9997967d2939cf4a6.tar.gz
exploit mdct symmetry
2% faster vorbis on conroe, k8. 7% on celeron. Originally committed as revision 14207 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec')
-rw-r--r--libavcodec/dsputil.c15
-rw-r--r--libavcodec/dsputil.h8
-rw-r--r--libavcodec/fft.c3
-rw-r--r--libavcodec/i386/dsputil_mmx.c68
-rw-r--r--libavcodec/i386/fft_3dn2.c57
-rw-r--r--libavcodec/i386/fft_sse.c58
-rw-r--r--libavcodec/mdct.c57
-rw-r--r--libavcodec/vorbis_dec.c20
8 files changed, 241 insertions, 45 deletions
diff --git a/libavcodec/dsputil.c b/libavcodec/dsputil.c
index 55929d0e76..212e2415da 100644
--- a/libavcodec/dsputil.c
+++ b/libavcodec/dsputil.c
@@ -3931,9 +3931,18 @@ void ff_vector_fmul_add_add_c(float *dst, const float *src0, const float *src1,
}
void ff_vector_fmul_window_c(float *dst, const float *src0, const float *src1, const float *win, float add_bias, int len){
- int i;
- for(i=0; i<len; i++)
- dst[i] = src0[i]*win[len-i-1] + src1[i]*win[i] + add_bias;
+ int i,j;
+ dst += len;
+ win += len;
+ src0+= len;
+ for(i=-len, j=len-1; i<0; i++, j--) {
+ float s0 = src0[i];
+ float s1 = src1[j];
+ float wi = win[i];
+ float wj = win[j];
+ dst[i] = s0*wj - s1*wi + add_bias;
+ dst[j] = s0*wi + s1*wj + add_bias;
+ }
}
static av_always_inline int float_to_int16_one(const float *src){
diff --git a/libavcodec/dsputil.h b/libavcodec/dsputil.h
index 34c4129442..e44eaa2c48 100644
--- a/libavcodec/dsputil.h
+++ b/libavcodec/dsputil.h
@@ -641,6 +641,8 @@ typedef struct FFTContext {
void (*fft_calc)(struct FFTContext *s, FFTComplex *z);
void (*imdct_calc)(struct MDCTContext *s, FFTSample *output,
const FFTSample *input, FFTSample *tmp);
+ void (*imdct_half)(struct MDCTContext *s, FFTSample *output,
+ const FFTSample *input, FFTSample *tmp);
} FFTContext;
int ff_fft_init(FFTContext *s, int nbits, int inverse);
@@ -686,10 +688,16 @@ void ff_sine_window_init(float *window, int n);
int ff_mdct_init(MDCTContext *s, int nbits, int inverse);
void ff_imdct_calc(MDCTContext *s, FFTSample *output,
const FFTSample *input, FFTSample *tmp);
+void ff_imdct_half(MDCTContext *s, FFTSample *output,
+ const FFTSample *input, FFTSample *tmp);
void ff_imdct_calc_3dn2(MDCTContext *s, FFTSample *output,
const FFTSample *input, FFTSample *tmp);
+void ff_imdct_half_3dn2(MDCTContext *s, FFTSample *output,
+ const FFTSample *input, FFTSample *tmp);
void ff_imdct_calc_sse(MDCTContext *s, FFTSample *output,
const FFTSample *input, FFTSample *tmp);
+void ff_imdct_half_sse(MDCTContext *s, FFTSample *output,
+ const FFTSample *input, FFTSample *tmp);
void ff_mdct_calc(MDCTContext *s, FFTSample *out,
const FFTSample *input, FFTSample *tmp);
void ff_mdct_end(MDCTContext *s);
diff --git a/libavcodec/fft.c b/libavcodec/fft.c
index 7ef5d37c73..47e9e062f4 100644
--- a/libavcodec/fft.c
+++ b/libavcodec/fft.c
@@ -59,6 +59,7 @@ int ff_fft_init(FFTContext *s, int nbits, int inverse)
}
s->fft_calc = ff_fft_calc_c;
s->imdct_calc = ff_imdct_calc;
+ s->imdct_half = ff_imdct_half;
s->exptab1 = NULL;
#ifdef HAVE_MMX
@@ -67,6 +68,7 @@ int ff_fft_init(FFTContext *s, int nbits, int inverse)
if (has_vectors & MM_3DNOWEXT) {
/* 3DNowEx for K7/K8 */
s->imdct_calc = ff_imdct_calc_3dn2;
+ s->imdct_half = ff_imdct_half_3dn2;
s->fft_calc = ff_fft_calc_3dn2;
} else if (has_vectors & MM_3DNOW) {
/* 3DNow! for K6-2/3 */
@@ -74,6 +76,7 @@ int ff_fft_init(FFTContext *s, int nbits, int inverse)
} else if (has_vectors & MM_SSE) {
/* SSE for P3/P4 */
s->imdct_calc = ff_imdct_calc_sse;
+ s->imdct_half = ff_imdct_half_sse;
s->fft_calc = ff_fft_calc_sse;
} else {
shuffle = 0;
diff --git a/libavcodec/i386/dsputil_mmx.c b/libavcodec/i386/dsputil_mmx.c
index 5ee168b3e3..db8be862dd 100644
--- a/libavcodec/i386/dsputil_mmx.c
+++ b/libavcodec/i386/dsputil_mmx.c
@@ -2022,33 +2022,71 @@ static void vector_fmul_add_add_sse(float *dst, const float *src0, const float *
ff_vector_fmul_add_add_c(dst, src0, src1, src2, src3, len, step);
}
+static void vector_fmul_window_3dnow2(float *dst, const float *src0, const float *src1,
+ const float *win, float add_bias, int len){
+#ifdef HAVE_6REGS
+ if(add_bias == 0){
+ x86_reg i = -len*4;
+ x86_reg j = len*4-8;
+ asm volatile(
+ "1: \n"
+ "pswapd (%5,%1), %%mm1 \n"
+ "movq (%5,%0), %%mm0 \n"
+ "pswapd (%4,%1), %%mm5 \n"
+ "movq (%3,%0), %%mm4 \n"
+ "movq %%mm0, %%mm2 \n"
+ "movq %%mm1, %%mm3 \n"
+ "pfmul %%mm4, %%mm2 \n" // src0[len+i]*win[len+i]
+ "pfmul %%mm5, %%mm3 \n" // src1[ j]*win[len+j]
+ "pfmul %%mm4, %%mm1 \n" // src0[len+i]*win[len+j]
+ "pfmul %%mm5, %%mm0 \n" // src1[ j]*win[len+i]
+ "pfadd %%mm3, %%mm2 \n"
+ "pfsub %%mm0, %%mm1 \n"
+ "pswapd %%mm2, %%mm2 \n"
+ "movq %%mm1, (%2,%0) \n"
+ "movq %%mm2, (%2,%1) \n"
+ "sub $8, %1 \n"
+ "add $8, %0 \n"
+ "jl 1b \n"
+ "femms \n"
+ :"+r"(i), "+r"(j)
+ :"r"(dst+len), "r"(src0+len), "r"(src1), "r"(win+len)
+ );
+ }else
+#endif
+ ff_vector_fmul_window_c(dst, src0, src1, win, add_bias, len);
+}
+
static void vector_fmul_window_sse(float *dst, const float *src0, const float *src1,
const float *win, float add_bias, int len){
#ifdef HAVE_6REGS
if(add_bias == 0){
- x86_reg i = -len*2;
- x86_reg j = len*2-16;
+ x86_reg i = -len*4;
+ x86_reg j = len*4-16;
asm volatile(
"1: \n"
- "movaps (%5,%0), %%xmm0 \n"
"movaps (%5,%1), %%xmm1 \n"
+ "movaps (%5,%0), %%xmm0 \n"
+ "movaps (%4,%1), %%xmm5 \n"
+ "movaps (%3,%0), %%xmm4 \n"
+ "shufps $0x1b, %%xmm1, %%xmm1 \n"
+ "shufps $0x1b, %%xmm5, %%xmm5 \n"
"movaps %%xmm0, %%xmm2 \n"
"movaps %%xmm1, %%xmm3 \n"
+ "mulps %%xmm4, %%xmm2 \n" // src0[len+i]*win[len+i]
+ "mulps %%xmm5, %%xmm3 \n" // src1[ j]*win[len+j]
+ "mulps %%xmm4, %%xmm1 \n" // src0[len+i]*win[len+j]
+ "mulps %%xmm5, %%xmm0 \n" // src1[ j]*win[len+i]
+ "addps %%xmm3, %%xmm2 \n"
+ "subps %%xmm0, %%xmm1 \n"
"shufps $0x1b, %%xmm2, %%xmm2 \n"
- "shufps $0x1b, %%xmm3, %%xmm3 \n"
- "mulps (%4,%0), %%xmm0 \n"
- "mulps (%4,%1), %%xmm1 \n"
- "mulps (%3,%0), %%xmm3 \n"
- "mulps (%3,%1), %%xmm2 \n"
- "addps %%xmm3, %%xmm0 \n"
- "addps %%xmm2, %%xmm1 \n"
- "movaps %%xmm0, (%2,%0) \n"
- "movaps %%xmm1, (%2,%1) \n"
+ "movaps %%xmm1, (%2,%0) \n"
+ "movaps %%xmm2, (%2,%1) \n"
"sub $16, %1 \n"
"add $16, %0 \n"
"jl 1b \n"
:"+r"(i), "+r"(j)
- :"r"(dst+len/2), "r"(src0+len/2), "r"(src1+len/2), "r"(win+len/2)
+ :"r"(dst+len), "r"(src0+len), "r"(src1), "r"(win+len)
);
}else
#endif
@@ -2638,8 +2676,10 @@ void dsputil_init_mmx(DSPContext* c, AVCodecContext *avctx)
c->float_to_int16_interleave = float_to_int16_interleave_3dnow;
}
}
- if(mm_flags & MM_3DNOWEXT)
+ if(mm_flags & MM_3DNOWEXT){
c->vector_fmul_reverse = vector_fmul_reverse_3dnow2;
+ c->vector_fmul_window = vector_fmul_window_3dnow2;
+ }
if(mm_flags & MM_SSE){
c->vorbis_inverse_coupling = vorbis_inverse_coupling_sse;
c->vector_fmul = vector_fmul_sse;
diff --git a/libavcodec/i386/fft_3dn2.c b/libavcodec/i386/fft_3dn2.c
index 32c4be369b..9068dff24b 100644
--- a/libavcodec/i386/fft_3dn2.c
+++ b/libavcodec/i386/fft_3dn2.c
@@ -124,10 +124,9 @@ void ff_fft_calc_3dn2(FFTContext *s, FFTComplex *z)
asm volatile("femms");
}
-void ff_imdct_calc_3dn2(MDCTContext *s, FFTSample *output,
- const FFTSample *input, FFTSample *tmp)
+static void imdct_3dn2(MDCTContext *s, const FFTSample *input, FFTSample *tmp)
{
- long n8, n4, n2, n;
+ long n4, n2, n;
x86_reg k;
const uint16_t *revtab = s->fft.revtab;
const FFTSample *tcos = s->tcos;
@@ -138,7 +137,6 @@ void ff_imdct_calc_3dn2(MDCTContext *s, FFTSample *output,
n = 1 << s->nbits;
n2 = n >> 1;
n4 = n >> 2;
- n8 = n >> 3;
/* pre rotation */
in1 = input;
@@ -182,6 +180,20 @@ void ff_imdct_calc_3dn2(MDCTContext *s, FFTSample *output,
:"m"(tcos[k]), "m"(tsin[k])
);
}
+}
+
+void ff_imdct_calc_3dn2(MDCTContext *s, FFTSample *output,
+ const FFTSample *input, FFTSample *tmp)
+{
+ x86_reg k;
+ long n8, n2, n;
+ FFTComplex *z = (FFTComplex *)tmp;
+
+ n = 1 << s->nbits;
+ n2 = n >> 1;
+ n8 = n >> 3;
+
+ imdct_3dn2(s, input, tmp);
k = n-8;
asm volatile("movd %0, %%mm7" ::"r"(1<<31));
@@ -212,3 +224,40 @@ void ff_imdct_calc_3dn2(MDCTContext *s, FFTSample *output,
asm volatile("femms");
}
+void ff_imdct_half_3dn2(MDCTContext *s, FFTSample *output,
+ const FFTSample *input, FFTSample *tmp)
+{
+ x86_reg j, k;
+ long n8, n4, n;
+ FFTComplex *z = (FFTComplex *)tmp;
+
+ n = 1 << s->nbits;
+ n4 = n >> 2;
+ n8 = n >> 3;
+
+ imdct_3dn2(s, input, tmp);
+
+ j = -n;
+ k = n-8;
+ asm volatile("movd %0, %%mm7" ::"r"(1<<31));
+ asm volatile(
+ "1: \n\t"
+ "movq (%3,%1), %%mm0 \n\t" // z[n8+k]
+ "pswapd (%3,%0), %%mm1 \n\t" // z[n8-1-k]
+ "movq %%mm0, %%mm2 \n\t"
+ "punpckldq %%mm1, %%mm0 \n\t"
+ "punpckhdq %%mm2, %%mm1 \n\t"
+ "pxor %%mm7, %%mm0 \n\t"
+ "pxor %%mm7, %%mm1 \n\t"
+ "movq %%mm0, (%2,%1) \n\t" // output[n4+2*k] = { -z[n8+k].re, z[n8-1-k].im }
+ "movq %%mm1, (%2,%0) \n\t" // output[n4-2-2*k] = { -z[n8-1-k].re, z[n8+k].im }
+ "sub $8, %1 \n\t"
+ "add $8, %0 \n\t"
+ "jl 1b \n\t"
+ :"+r"(j), "+r"(k)
+ :"r"(output+n4), "r"(z+n8)
+ :"memory"
+ );
+ asm volatile("femms");
+}
+
diff --git a/libavcodec/i386/fft_sse.c b/libavcodec/i386/fft_sse.c
index 83cbd87088..305f44a0ce 100644
--- a/libavcodec/i386/fft_sse.c
+++ b/libavcodec/i386/fft_sse.c
@@ -142,11 +142,10 @@ void ff_fft_calc_sse(FFTContext *s, FFTComplex *z)
} while (nblocks != 0);
}
-void ff_imdct_calc_sse(MDCTContext *s, FFTSample *output,
- const FFTSample *input, FFTSample *tmp)
+static void imdct_sse(MDCTContext *s, const FFTSample *input, FFTSample *tmp)
{
x86_reg k;
- long n8, n4, n2, n;
+ long n4, n2, n;
const uint16_t *revtab = s->fft.revtab;
const FFTSample *tcos = s->tcos;
const FFTSample *tsin = s->tsin;
@@ -156,7 +155,6 @@ void ff_imdct_calc_sse(MDCTContext *s, FFTSample *output,
n = 1 << s->nbits;
n2 = n >> 1;
n4 = n >> 2;
- n8 = n >> 3;
#ifdef ARCH_X86_64
asm volatile ("movaps %0, %%xmm8\n\t"::"m"(*p1m1p1m1));
@@ -260,6 +258,20 @@ void ff_imdct_calc_sse(MDCTContext *s, FFTSample *output,
#endif
);
}
+}
+
+void ff_imdct_calc_sse(MDCTContext *s, FFTSample *output,
+ const FFTSample *input, FFTSample *tmp)
+{
+ x86_reg k;
+ long n8, n2, n;
+ FFTComplex *z = (FFTComplex *)tmp;
+
+ n = 1 << s->nbits;
+ n2 = n >> 1;
+ n8 = n >> 3;
+
+ imdct_sse(s, input, tmp);
/*
Mnemonics:
@@ -301,3 +313,41 @@ void ff_imdct_calc_sse(MDCTContext *s, FFTSample *output,
);
}
+void ff_imdct_half_sse(MDCTContext *s, FFTSample *output,
+ const FFTSample *input, FFTSample *tmp)
+{
+ x86_reg j, k;
+ long n8, n4, n;
+ FFTComplex *z = (FFTComplex *)tmp;
+
+ n = 1 << s->nbits;
+ n4 = n >> 2;
+ n8 = n >> 3;
+
+ imdct_sse(s, input, tmp);
+
+ j = -n;
+ k = n-16;
+ asm volatile("movaps %0, %%xmm7 \n\t"::"m"(*m1m1m1m1));
+ asm volatile(
+ "1: \n\t"
+ "movaps (%3,%1), %%xmm0 \n\t"
+ "movaps (%3,%0), %%xmm1 \n\t"
+ "xorps %%xmm7, %%xmm0 \n\t"
+ "movaps %%xmm0, %%xmm2 \n\t"
+ "shufps $141,%%xmm1, %%xmm0 \n\t"
+ "shufps $216,%%xmm1, %%xmm2 \n\t"
+ "shufps $54, %%xmm0, %%xmm0 \n\t"
+ "shufps $156,%%xmm2, %%xmm2 \n\t"
+ "xorps %%xmm7, %%xmm0 \n\t"
+ "movaps %%xmm2, (%2,%1) \n\t"
+ "movaps %%xmm0, (%2,%0) \n\t"
+ "sub $16, %1 \n\t"
+ "add $16, %0 \n\t"
+ "jl 1b \n\t"
+ :"+r"(j), "+r"(k)
+ :"r"(output+n4), "r"(z+n8)
+ :"memory"
+ );
+}
+
diff --git a/libavcodec/mdct.c b/libavcodec/mdct.c
index 07eef2b3d4..6a3b69a014 100644
--- a/libavcodec/mdct.c
+++ b/libavcodec/mdct.c
@@ -100,16 +100,9 @@ int ff_mdct_init(MDCTContext *s, int nbits, int inverse)
(pim) = _are * _bim + _aim * _bre;\
}
-/**
- * Compute inverse MDCT of size N = 2^nbits
- * @param output N samples
- * @param input N/2 samples
- * @param tmp N/2 samples
- */
-void ff_imdct_calc(MDCTContext *s, FFTSample *output,
- const FFTSample *input, FFTSample *tmp)
+static void imdct_c(MDCTContext *s, const FFTSample *input, FFTSample *tmp)
{
- int k, n8, n4, n2, n, j;
+ int k, n4, n2, n, j;
const uint16_t *revtab = s->fft.revtab;
const FFTSample *tcos = s->tcos;
const FFTSample *tsin = s->tsin;
@@ -119,7 +112,6 @@ void ff_imdct_calc(MDCTContext *s, FFTSample *output,
n = 1 << s->nbits;
n2 = n >> 1;
n4 = n >> 2;
- n8 = n >> 3;
/* pre rotation */
in1 = input;
@@ -137,6 +129,25 @@ void ff_imdct_calc(MDCTContext *s, FFTSample *output,
for(k = 0; k < n4; k++) {
CMUL(z[k].re, z[k].im, z[k].re, z[k].im, tcos[k], tsin[k]);
}
+}
+
+/**
+ * Compute inverse MDCT of size N = 2^nbits
+ * @param output N samples
+ * @param input N/2 samples
+ * @param tmp N/2 samples
+ */
+void ff_imdct_calc(MDCTContext *s, FFTSample *output,
+ const FFTSample *input, FFTSample *tmp)
+{
+ int k, n8, n2, n;
+ FFTComplex *z = (FFTComplex *)tmp;
+ n = 1 << s->nbits;
+ n2 = n >> 1;
+ n8 = n >> 3;
+
+ imdct_c(s, input, tmp);
+
for(k = 0; k < n8; k++) {
output[2*k] = -z[n8 + k].im;
output[n2-1-2*k] = z[n8 + k].im;
@@ -153,6 +164,32 @@ void ff_imdct_calc(MDCTContext *s, FFTSample *output,
}
/**
+ * Compute the middle half of the inverse MDCT of size N = 2^nbits,
+ * thus excluding the parts that can be derived by symmetry
+ * @param output N/2 samples
+ * @param input N/2 samples
+ * @param tmp N/2 samples
+ */
+void ff_imdct_half(MDCTContext *s, FFTSample *output,
+ const FFTSample *input, FFTSample *tmp)
+{
+ int k, n8, n4, n;
+ FFTComplex *z = (FFTComplex *)tmp;
+ n = 1 << s->nbits;
+ n4 = n >> 2;
+ n8 = n >> 3;
+
+ imdct_c(s, input, tmp);
+
+ for(k = 0; k < n8; k++) {
+ output[n4-1-2*k] = z[n8+k].im;
+ output[n4-1-2*k-1] = -z[n8-k-1].re;
+ output[n4 + 2*k] = -z[n8+k].re;
+ output[n4 + 2*k+1] = z[n8-k-1].im;
+ }
+}
+
+/**
* Compute MDCT of size N = 2^nbits
* @param input N samples
* @param out N/2 samples
diff --git a/libavcodec/vorbis_dec.c b/libavcodec/vorbis_dec.c
index ed13229cd4..d4a5402d86 100644
--- a/libavcodec/vorbis_dec.c
+++ b/libavcodec/vorbis_dec.c
@@ -899,10 +899,10 @@ static int vorbis_parse_id_hdr(vorbis_context *vc){
vc->channel_residues= av_malloc((vc->blocksize[1]/2)*vc->audio_channels * sizeof(float));
vc->channel_floors = av_malloc((vc->blocksize[1]/2)*vc->audio_channels * sizeof(float));
- vc->saved = av_mallocz((vc->blocksize[1]/2)*vc->audio_channels * sizeof(float));
+ vc->saved = av_mallocz((vc->blocksize[1]/4)*vc->audio_channels * sizeof(float));
vc->ret = av_malloc((vc->blocksize[1]/2)*vc->audio_channels * sizeof(float));
- vc->buf = av_malloc( vc->blocksize[1] * sizeof(float));
- vc->buf_tmp = av_malloc( vc->blocksize[1] * sizeof(float));
+ vc->buf = av_malloc( vc->blocksize[1]/2 * sizeof(float));
+ vc->buf_tmp = av_malloc( vc->blocksize[1]/2 * sizeof(float));
vc->previous_window=0;
ff_mdct_init(&vc->mdct[0], bl0, 1);
@@ -1520,23 +1520,23 @@ static int vorbis_parse_audio_packet(vorbis_context *vc) {
for(j=0;j<vc->audio_channels;++j) {
uint_fast16_t bs0=vc->blocksize[0];
uint_fast16_t bs1=vc->blocksize[1];
- float *saved=vc->saved+j*bs1/2;
+ float *saved=vc->saved+j*bs1/4;
float *ret=vc->ret+j*retlen;
float *buf=vc->buf;
const float *win=vc->win[blockflag&previous_window];
- vc->mdct[0].fft.imdct_calc(&vc->mdct[blockflag], buf, vc->channel_floors+j*blocksize/2, vc->buf_tmp);
+ vc->mdct[0].fft.imdct_half(&vc->mdct[blockflag], buf, vc->channel_floors+j*blocksize/2, vc->buf_tmp);
if(blockflag == previous_window) {
- vc->dsp.vector_fmul_window(ret, saved, buf, win, fadd_bias, blocksize/2);
+ vc->dsp.vector_fmul_window(ret, saved, buf, win, fadd_bias, blocksize/4);
} else if(blockflag > previous_window) {
- vc->dsp.vector_fmul_window(ret, saved, buf+(bs1-bs0)/4, win, fadd_bias, bs0/2);
- copy_normalize(ret+bs0/2, buf+(bs1+bs0)/4, (bs1-bs0)/4, vc->exp_bias, fadd_bias);
+ vc->dsp.vector_fmul_window(ret, saved, buf, win, fadd_bias, bs0/4);
+ copy_normalize(ret+bs0/2, buf+bs0/4, (bs1-bs0)/4, vc->exp_bias, fadd_bias);
} else {
copy_normalize(ret, saved, (bs1-bs0)/4, vc->exp_bias, fadd_bias);
- vc->dsp.vector_fmul_window(ret+(bs1-bs0)/4, saved+(bs1-bs0)/4, buf, win, fadd_bias, bs0/2);
+ vc->dsp.vector_fmul_window(ret+(bs1-bs0)/4, saved+(bs1-bs0)/4, buf, win, fadd_bias, bs0/4);
}
- memcpy(saved, buf+blocksize/2, blocksize/2*sizeof(float));
+ memcpy(saved, buf+blocksize/4, blocksize/4*sizeof(float));
}
vc->previous_window = blockflag;