removed unused code - began to merge alpha specific stuff - added mac macros for suitable CPUs

Originally committed as revision 667 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 160 insertions, 345 deletions

diff --git a/libavcodec/simple_idct.c b/libavcodec/simple_idct.c
index dc8bf3a003..a4d4486af5 100644
--- a/libavcodec/simple_idct.c
+++ b/libavcodec/simple_idct.c
@@ -47,61 +47,29 @@
 #define COL_SHIFT 20 // 6
 #endif
 
-/* 8x8 Matrix used to do a trivial (slow) 8 point IDCT */
-static int coeff[64]={
-	W4, W4, W4, W4, W4, W4, W4, W4,
-	W1, W3, W5, W7,-W7,-W5,-W3,-W1,
-	W2, W6,-W6,-W2,-W2,-W6, W6, W2,
-	W3,-W7,-W1,-W5, W5, W1, W7,-W3,
-	W4,-W4,-W4, W4, W4,-W4,-W4, W4,
-	W5,-W1, W7, W3,-W3,-W7, W1,-W5,
-	W6,-W2, W2,-W6,-W6, W2,-W2, W6,
-	W7,-W5, W3,-W1, W1,-W3, W5,-W7
-};
-
-static inline int idctRowCondZ (int16_t * row)
-{
-	int a0, a1, a2, a3, b0, b1, b2, b3;
+#ifdef ARCH_ALPHA
+#define FAST_64BIT
+#endif
 
-	if( !( ((uint32_t*)row)[0]|((uint32_t*)row)[1] |((uint32_t*)row)[2] |((uint32_t*)row)[3])) {
-/*		row[0] = row[1] = row[2] = row[3] = row[4] =
-			row[5] = row[6] = row[7] = 0;*/
-		return 0;
-	}
+#if defined(ARCH_POWERPC_405)
 
-	if(!( ((uint32_t*)row)[2] |((uint32_t*)row)[3] )){
-		a0 = W4*row[0] + W2*row[2] + (1<<(ROW_SHIFT-1));
-		a1 = W4*row[0] + W6*row[2] + (1<<(ROW_SHIFT-1));
-		a2 = W4*row[0] - W6*row[2] + (1<<(ROW_SHIFT-1));
-		a3 = W4*row[0] - W2*row[2] + (1<<(ROW_SHIFT-1));
-
-		b0 = W1*row[1] + W3*row[3];
-		b1 = W3*row[1] - W7*row[3];
-		b2 = W5*row[1] - W1*row[3];
-		b3 = W7*row[1] - W5*row[3];
-	}else{
-		a0 = W4*row[0] + W2*row[2] + W4*row[4] + W6*row[6] + (1<<(ROW_SHIFT-1));
-		a1 = W4*row[0] + W6*row[2] - W4*row[4] - W2*row[6] + (1<<(ROW_SHIFT-1));
-		a2 = W4*row[0] - W6*row[2] - W4*row[4] + W2*row[6] + (1<<(ROW_SHIFT-1));
-		a3 = W4*row[0] - W2*row[2] + W4*row[4] - W6*row[6] + (1<<(ROW_SHIFT-1));
-
-		b0 = W1*row[1] + W3*row[3] + W5*row[5] + W7*row[7];
-		b1 = W3*row[1] - W7*row[3] - W1*row[5] - W5*row[7];
-		b2 = W5*row[1] - W1*row[3] + W7*row[5] + W3*row[7];
-		b3 = W7*row[1] - W5*row[3] + W3*row[5] - W1*row[7];
-	}
+/* signed 16x16 -> 32 multiply add accumulate */
+#define MAC16(rt, ra, rb) \
+    asm ("maclhw %0, %2, %3" : "=r" (rt) : "0" (rt), "r" (ra), "r" (rb));
 
-	row[0] = (a0 + b0) >> ROW_SHIFT;
-	row[1] = (a1 + b1) >> ROW_SHIFT;
-	row[2] = (a2 + b2) >> ROW_SHIFT;
-	row[3] = (a3 + b3) >> ROW_SHIFT;
-	row[4] = (a3 - b3) >> ROW_SHIFT;
-	row[5] = (a2 - b2) >> ROW_SHIFT;
-	row[6] = (a1 - b1) >> ROW_SHIFT;
-	row[7] = (a0 - b0) >> ROW_SHIFT;
-	
-	return 1;
-}
+/* signed 16x16 -> 32 multiply */
+#define MUL16(rt, ra, rb) \
+    asm ("mullhw %0, %1, %2" : "=r" (rt) : "r" (ra), "r" (rb));
+
+#else
+
+/* signed 16x16 -> 32 multiply add accumulate */
+#define MAC16(rt, ra, rb) rt += (ra) * (rb)
+
+/* signed 16x16 -> 32 multiply */
+#define MUL16(rt, ra, rb) rt = (ra) * (rb)
+
+#endif
 
 #ifdef ARCH_ALPHA
 /* 0: all entries 0, 1: only first entry nonzero, 2: otherwise  */
@@ -129,10 +97,10 @@ static inline int idctRowCondDC(int16_t *row)
 		}
 	}
 
-	a0 = W4 * row[0];
-	a1 = W4 * row[0];
-	a2 = W4 * row[0];
-	a3 = W4 * row[0];
+        a0 = (W4 * row[0]) + (1 << (ROW_SHIFT - 1));
+	a1 = a0;
+	a2 = a0;
+	a3 = a0;
 
 	if (row[2]) {
 		a0 += W2 * row[2];
@@ -155,11 +123,6 @@ static inline int idctRowCondDC(int16_t *row)
 		a3 -= W6 * row[6];
 	}
 
-	a0 += 1 << (ROW_SHIFT - 1);
-	a1 += 1 << (ROW_SHIFT - 1);
-	a2 += 1 << (ROW_SHIFT - 1);
-	a3 += 1 << (ROW_SHIFT - 1);
-
 	if (row[1]) {
 		b0 = W1 * row[1];
 		b1 = W3 * row[1];
@@ -205,38 +168,86 @@ static inline int idctRowCondDC(int16_t *row)
 	return 2;
 }
 #else  /* not ARCH_ALPHA */
-static inline int idctRowCondDC (int16_t * row)
+
+static inline void idctRowCondDC (int16_t * row)
 {
 	int a0, a1, a2, a3, b0, b1, b2, b3;
+#ifdef FAST_64BIT
+        uint64_t temp;
+#else
+        uint32_t temp;
+#endif
 
-	if( !( ((uint32_t*)row)[1] |((uint32_t*)row)[2] |((uint32_t*)row)[3]| row[1])) {
-//		row[0] = row[1] = row[2] = row[3] = row[4] = row[5] = row[6] = row[7] = row[0]<<3;
-		uint16_t temp= row[0]<<3;
-		((uint32_t*)row)[0]=((uint32_t*)row)[1]=
-		((uint32_t*)row)[2]=((uint32_t*)row)[3]= temp + (temp<<16);
-		return 0;
+#ifdef FAST_64BIT
+#ifdef WORDS_BIGENDIAN
+#define ROW0_MASK 0xffff000000000000LL
+#else
+#define ROW0_MASK 0xffffLL
+#endif
+	if ( ((((uint64_t *)row)[0] & ~ROW0_MASK) | 
+              ((uint64_t *)row)[1]) == 0) {
+            temp = (row[0] << 3) & 0xffff;
+            temp += temp << 16;
+            temp += temp << 32;
+            ((uint64_t *)row)[0] = temp;
+            ((uint64_t *)row)[1] = temp;
+            return;
 	}
+#else
+	if (!(((uint32_t*)row)[1] |
+              ((uint32_t*)row)[2] |
+              ((uint32_t*)row)[3] | 
+              row[1])) {
+            temp = (row[0] << 3) & 0xffff;
+            temp += temp << 16;
+            ((uint32_t*)row)[0]=((uint32_t*)row)[1] =
+		((uint32_t*)row)[2]=((uint32_t*)row)[3] = temp;
+		return;
+	}
+#endif
 
-	if(!( ((uint32_t*)row)[2] |((uint32_t*)row)[3] )){
-		a0 = W4*row[0] + W2*row[2] + (1<<(ROW_SHIFT-1));
-		a1 = W4*row[0] + W6*row[2] + (1<<(ROW_SHIFT-1));
-		a2 = W4*row[0] - W6*row[2] + (1<<(ROW_SHIFT-1));
-		a3 = W4*row[0] - W2*row[2] + (1<<(ROW_SHIFT-1));
-
-		b0 = W1*row[1] + W3*row[3];
-		b1 = W3*row[1] - W7*row[3];
-		b2 = W5*row[1] - W1*row[3];
-		b3 = W7*row[1] - W5*row[3];
-	}else{
-		a0 = W4*row[0] + W2*row[2] + W4*row[4] + W6*row[6] + (1<<(ROW_SHIFT-1));
-		a1 = W4*row[0] + W6*row[2] - W4*row[4] - W2*row[6] + (1<<(ROW_SHIFT-1));
-		a2 = W4*row[0] - W6*row[2] - W4*row[4] + W2*row[6] + (1<<(ROW_SHIFT-1));
-		a3 = W4*row[0] - W2*row[2] + W4*row[4] - W6*row[6] + (1<<(ROW_SHIFT-1));
-
-		b0 = W1*row[1] + W3*row[3] + W5*row[5] + W7*row[7];
-		b1 = W3*row[1] - W7*row[3] - W1*row[5] - W5*row[7];
-		b2 = W5*row[1] - W1*row[3] + W7*row[5] + W3*row[7];
-		b3 = W7*row[1] - W5*row[3] + W3*row[5] - W1*row[7];
+        a0 = (W4 * row[0]) + (1 << (ROW_SHIFT - 1));
+	a1 = a0;
+	a2 = a0;
+	a3 = a0;
+
+        /* no need to optimize : gcc does it */
+        a0 += W2 * row[2];
+        a1 += W6 * row[2];
+        a2 -= W6 * row[2];
+        a3 -= W2 * row[2];
+
+        MUL16(b0, W1, row[1]);
+        MAC16(b0, W3, row[3]);
+        MUL16(b1, W3, row[1]);
+        MAC16(b1, -W7, row[3]);
+        MUL16(b2, W5, row[1]);
+        MAC16(b2, -W1, row[3]);
+        MUL16(b3, W7, row[1]);
+        MAC16(b3, -W5, row[3]);
+
+#ifdef FAST_64BIT
+        temp = ((uint64_t*)row)[1];
+#else
+        temp = ((uint32_t*)row)[2] | ((uint32_t*)row)[3];
+#endif
+	if (temp != 0) {
+            a0 += W4*row[4] + W6*row[6];
+            a1 += - W4*row[4] - W2*row[6];
+            a2 += - W4*row[4] + W2*row[6];
+            a3 += W4*row[4] - W6*row[6];
+
+            MAC16(b0, W5, row[5]);
+            MAC16(b0, W7, row[7]);
+            
+            MAC16(b1, -W1, row[5]);
+            MAC16(b1, -W5, row[7]);
+            
+            MAC16(b2, W7, row[5]);
+            MAC16(b2, W3, row[7]);
+            
+            MAC16(b3, W3, row[5]);
+            MAC16(b3, -W1, row[7]);
 	}
 
 	row[0] = (a0 + b0) >> ROW_SHIFT;
@@ -247,202 +258,70 @@ static inline int idctRowCondDC (int16_t * row)
 	row[5] = (a2 - b2) >> ROW_SHIFT;
 	row[3] = (a3 + b3) >> ROW_SHIFT;
 	row[4] = (a3 - b3) >> ROW_SHIFT;
-	
-	return 1;
 }
 #endif /* not ARCH_ALPHA */
 
-static inline void idctCol (int16_t * col)
-{
-
-/*
-	if( !(col[8*1] | col[8*2] |col[8*3] |col[8*4] |col[8*5] |col[8*6] | col[8*7])) {
-		col[8*0] = col[8*1] = col[8*2] = col[8*3] = col[8*4] =
-			col[8*5] = col[8*6] = col[8*7] = col[8*0]<<3;
-		return;
-	}*/
-
-	int a0, a1, a2, a3, b0, b1, b2, b3;
-	col[0] += (1<<(COL_SHIFT-1))/W4;
-	a0 = W4*col[8*0] + W2*col[8*2] + W4*col[8*4] + W6*col[8*6];
-	a1 = W4*col[8*0] + W6*col[8*2] - W4*col[8*4] - W2*col[8*6];
-	a2 = W4*col[8*0] - W6*col[8*2] - W4*col[8*4] + W2*col[8*6];
-	a3 = W4*col[8*0] - W2*col[8*2] + W4*col[8*4] - W6*col[8*6];
-
-	b0 = W1*col[8*1] + W3*col[8*3] + W5*col[8*5] + W7*col[8*7];
-	b1 = W3*col[8*1] - W7*col[8*3] - W1*col[8*5] - W5*col[8*7];
-	b2 = W5*col[8*1] - W1*col[8*3] + W7*col[8*5] + W3*col[8*7];
-	b3 = W7*col[8*1] - W5*col[8*3] + W3*col[8*5] - W1*col[8*7];
-
-	col[8*0] = (a0 + b0) >> COL_SHIFT;
-	col[8*7] = (a0 - b0) >> COL_SHIFT;
-	col[8*1] = (a1 + b1) >> COL_SHIFT;
-	col[8*6] = (a1 - b1) >> COL_SHIFT;
-	col[8*2] = (a2 + b2) >> COL_SHIFT;
-	col[8*5] = (a2 - b2) >> COL_SHIFT;
-	col[8*3] = (a3 + b3) >> COL_SHIFT;
-	col[8*4] = (a3 - b3) >> COL_SHIFT;
-}
-
 static inline void idctSparseCol (int16_t * col)
 {
 	int a0, a1, a2, a3, b0, b1, b2, b3;
-	col[0] += (1<<(COL_SHIFT-1))/W4;
-	a0 = W4*col[8*0];
-	a1 = W4*col[8*0];
-	a2 = W4*col[8*0];
-	a3 = W4*col[8*0];
-
-	if(col[8*2]){
-		a0 +=  + W2*col[8*2];
-		a1 +=  + W6*col[8*2];
-		a2 +=  - W6*col[8*2];
-		a3 +=  - W2*col[8*2];
-	}
 
-	if(col[8*4]){
-		a0 += + W4*col[8*4];
-		a1 += - W4*col[8*4];
-		a2 += - W4*col[8*4];
-		a3 += + W4*col[8*4];
-	}
+        /* XXX: I did that only to give same values as previous code */
+	a0 = W4 * (col[8*0] + ((1<<(COL_SHIFT-1))/W4));
+	a1 = a0;
+	a2 = a0;
+	a3 = a0;
 
-	if(col[8*6]){
-		a0 += + W6*col[8*6];
-		a1 += - W2*col[8*6];
-		a2 += + W2*col[8*6];
-		a3 += - W6*col[8*6];
-	}
-
-	if(col[8*1]){
-		b0 = W1*col[8*1];
-		b1 = W3*col[8*1];
-		b2 = W5*col[8*1];
-		b3 = W7*col[8*1];
-	}else{
-		b0 = 
-		b1 = 
-		b2 = 
-		b3 = 0;
-	}
-
-	if(col[8*3]){
-		b0 += + W3*col[8*3];
-		b1 += - W7*col[8*3];
-		b2 += - W1*col[8*3];
-		b3 += - W5*col[8*3];
-	}
-
-	if(col[8*5]){
-		b0 += + W5*col[8*5];
-		b1 += - W1*col[8*5];
-		b2 += + W7*col[8*5];
-		b3 += + W3*col[8*5];
-	}
-
-	if(col[8*7]){
-		b0 += + W7*col[8*7];
-		b1 += - W5*col[8*7];
-		b2 += + W3*col[8*7];
-		b3 += - W1*col[8*7];
-	}
+        a0 +=  + W2*col[8*2];
+        a1 +=  + W6*col[8*2];
+        a2 +=  - W6*col[8*2];
+        a3 +=  - W2*col[8*2];
 
-#ifndef ARCH_ALPHA
-	if(!(b0|b1|b2|b3)){
-		col[8*0] = (a0) >> COL_SHIFT;
-		col[8*7] = (a0) >> COL_SHIFT;
-		col[8*1] = (a1) >> COL_SHIFT;
-		col[8*6] = (a1) >> COL_SHIFT;
-		col[8*2] = (a2) >> COL_SHIFT;
-		col[8*5] = (a2) >> COL_SHIFT;
-		col[8*3] = (a3) >> COL_SHIFT;
-		col[8*4] = (a3) >> COL_SHIFT;
-	}else{
-#endif
-		col[8*0] = (a0 + b0) >> COL_SHIFT;
-		col[8*7] = (a0 - b0) >> COL_SHIFT;
-		col[8*1] = (a1 + b1) >> COL_SHIFT;
-		col[8*6] = (a1 - b1) >> COL_SHIFT;
-		col[8*2] = (a2 + b2) >> COL_SHIFT;
-		col[8*5] = (a2 - b2) >> COL_SHIFT;
-		col[8*3] = (a3 + b3) >> COL_SHIFT;
-		col[8*4] = (a3 - b3) >> COL_SHIFT;
-#ifndef ARCH_ALPHA
-	}
-#endif
-}
+        MUL16(b0, W1, col[8*1]);
+        MUL16(b1, W3, col[8*1]);
+        MUL16(b2, W5, col[8*1]);
+        MUL16(b3, W7, col[8*1]);
 
-static inline void idctSparse2Col (int16_t * col)
-{
-	int a0, a1, a2, a3, b0, b1, b2, b3;
-	col[0] += (1<<(COL_SHIFT-1))/W4;
-	a0 = W4*col[8*0];
-	a1 = W4*col[8*0];
-	a2 = W4*col[8*0];
-	a3 = W4*col[8*0];
-
-	if(col[8*2]){
-		a0 +=  + W2*col[8*2];
-		a1 +=  + W6*col[8*2];
-		a2 +=  - W6*col[8*2];
-		a3 +=  - W2*col[8*2];
-	}
+        MAC16(b0, + W3, col[8*3]);
+        MAC16(b1, - W7, col[8*3]);
+        MAC16(b2, - W1, col[8*3]);
+        MAC16(b3, - W5, col[8*3]);
 
 	if(col[8*4]){
-		a0 += + W4*col[8*4];
-		a1 += - W4*col[8*4];
-		a2 += - W4*col[8*4];
-		a3 += + W4*col[8*4];
+            a0 += + W4*col[8*4];
+            a1 += - W4*col[8*4];
+            a2 += - W4*col[8*4];
+            a3 += + W4*col[8*4];
 	}
 
-	if(col[8*6]){
-		a0 += + W6*col[8*6];
-		a1 += - W2*col[8*6];
-		a2 += + W2*col[8*6];
-		a3 += - W6*col[8*6];
-	}
-
-	if(col[8*1] || 1){
-		b0 = W1*col[8*1];
-		b1 = W3*col[8*1];
-		b2 = W5*col[8*1];
-		b3 = W7*col[8*1];
-	}else{
-		b0 = 
-		b1 = 
-		b2 = 
-		b3 = 0;
+	if (col[8*5]) {
+            MAC16(b0, + W5, col[8*5]);
+            MAC16(b1, - W1, col[8*5]);
+            MAC16(b2, + W7, col[8*5]);
+            MAC16(b3, + W3, col[8*5]);
 	}
 
-	if(col[8*3]){
-		b0 += + W3*col[8*3];
-		b1 += - W7*col[8*3];
-		b2 += - W1*col[8*3];
-		b3 += - W5*col[8*3];
-	}
-
-	if(col[8*5]){
-		b0 += + W5*col[8*5];
-		b1 += - W1*col[8*5];
-		b2 += + W7*col[8*5];
-		b3 += + W3*col[8*5];
-	}
-
-	if(col[8*7]){
-		b0 += + W7*col[8*7];
-		b1 += - W5*col[8*7];
-		b2 += + W3*col[8*7];
-		b3 += - W1*col[8*7];
-	}
-
-	col[8*0] = (a0 + b0) >> COL_SHIFT;
-	col[8*7] = (a0 - b0) >> COL_SHIFT;
-	col[8*1] = (a1 + b1) >> COL_SHIFT;
-	col[8*6] = (a1 - b1) >> COL_SHIFT;
-	col[8*2] = (a2 + b2) >> COL_SHIFT;
-	col[8*5] = (a2 - b2) >> COL_SHIFT;
-	col[8*3] = (a3 + b3) >> COL_SHIFT;
-	col[8*4] = (a3 - b3) >> COL_SHIFT;
+	if(col[8*6]){
+            a0 += + W6*col[8*6];
+            a1 += - W2*col[8*6];
+            a2 += + W2*col[8*6];
+            a3 += - W6*col[8*6];
+	}
+
+	if (col[8*7]) {
+            MAC16(b0, + W7, col[8*7]);
+            MAC16(b1, - W5, col[8*7]);
+            MAC16(b2, + W3, col[8*7]);
+            MAC16(b3, - W1, col[8*7]);
+	}
+
+        col[8*0] = (a0 + b0) >> COL_SHIFT;
+        col[8*7] = (a0 - b0) >> COL_SHIFT;
+        col[8*1] = (a1 + b1) >> COL_SHIFT;
+        col[8*6] = (a1 - b1) >> COL_SHIFT;
+        col[8*2] = (a2 + b2) >> COL_SHIFT;
+        col[8*5] = (a2 - b2) >> COL_SHIFT;
+        col[8*3] = (a3 + b3) >> COL_SHIFT;
+        col[8*4] = (a3 - b3) >> COL_SHIFT;
 }
 
 #ifdef ARCH_ALPHA
@@ -472,82 +351,11 @@ static inline void idctCol2(int16_t *col)
 	lcol[12] = l; lcol[13] = r;
 	lcol[14] = l; lcol[15] = r;
 }
-#endif
 
 void simple_idct (short *block)
 {
 
 	int i;
-	
-#if 0
-	int nonZero[8];
-	int buffer[64];
-	int nNonZero=0;
-	
-	idctRowCondDC(block);
-	
-	for(i=1; i<8; i++)
-	{
-		nonZero[nNonZero]=i;
-		nNonZero+= idctRowCondZ(block + i*8);
-	}
-	
-	if(nNonZero==0)
-	{
-		for(i=0; i<8; i++)
-		{
-			block[i   ]=
-			block[i+8 ]=
-			block[i+16]=
-			block[i+24]=
-			block[i+32]=
-			block[i+40]=
-			block[i+48]=
-			block[i+56]= (W4*block[i] + (1<<(COL_SHIFT-1))) >> COL_SHIFT;
-		}	
-	}
-	else if(nNonZero==1)
-	{
-		int index= nonZero[0]*8;
-		for(i=0; i<8; i++)
-		{
-			int bias= W4*block[i] + (1<<(COL_SHIFT-1));
-			int c= block[i + index];
-			block[i   ]= (c*coeff[index  ] + bias) >> COL_SHIFT;
-			block[i+8 ]= (c*coeff[index+1] + bias) >> COL_SHIFT;
-			block[i+16]= (c*coeff[index+2] + bias) >> COL_SHIFT;
-			block[i+24]= (c*coeff[index+3] + bias) >> COL_SHIFT;
-			block[i+32]= (c*coeff[index+4] + bias) >> COL_SHIFT;
-			block[i+40]= (c*coeff[index+5] + bias) >> COL_SHIFT;
-			block[i+48]= (c*coeff[index+6] + bias) >> COL_SHIFT;
-			block[i+56]= (c*coeff[index+7] + bias) >> COL_SHIFT;
-		}	
-	}
-/*	else if(nNonZero==2)
-	{
-		int index1= nonZero[0]*8;
-		int index2= nonZero[1]*8;
-		for(i=0; i<8; i++)
-		{
-			int bias= W4*block[i] + (1<<(COL_SHIFT-1));
-			int c1= block[i + index1];
-			int c2= block[i + index2];
-			block[i   ]= (c1*coeff[index1  ] + c2*coeff[index2  ] + bias) >> COL_SHIFT;
-			block[i+8 ]= (c1*coeff[index1+1] + c2*coeff[index2+1] + bias) >> COL_SHIFT;
-			block[i+16]= (c1*coeff[index1+2] + c2*coeff[index2+2] + bias) >> COL_SHIFT;
-			block[i+24]= (c1*coeff[index1+3] + c2*coeff[index2+3] + bias) >> COL_SHIFT;
-			block[i+32]= (c1*coeff[index1+4] + c2*coeff[index2+4] + bias) >> COL_SHIFT;
-			block[i+40]= (c1*coeff[index1+5] + c2*coeff[index2+5] + bias) >> COL_SHIFT;
-			block[i+48]= (c1*coeff[index1+6] + c2*coeff[index2+6] + bias) >> COL_SHIFT;
-			block[i+56]= (c1*coeff[index1+7] + c2*coeff[index2+7] + bias) >> COL_SHIFT;
-		}	
-	}*/
-	else
-	{
-		for(i=0; i<8; i++)
-			idctSparse2Col(block + i);
-	}
-#elif defined(ARCH_ALPHA)
         int rowsZero = 1;       /* all rows except row 0 zero */
         int rowsConstant = 1;	/* all rows consist of a constant value */
 
@@ -579,13 +387,20 @@ void simple_idct (short *block)
 		for (i = 0; i < 8; i++)
 			idctSparseCol(block + i);
 	}
+}
+
 #else
-	for(i=0; i<8; i++)
-		idctRowCondDC(block + i*8);
-	
-	for(i=0; i<8; i++)
-		idctSparseCol(block + i);
-#endif
+
+void simple_idct (short *block)
+{
+    int i;
+    for(i=0; i<8; i++)
+        idctRowCondDC(block + i*8);
+    
+    for(i=0; i<8; i++)
+        idctSparseCol(block + i);
 }
 
+#endif
+
 #undef COL_SHIFT