Convert Huffman decode from inline function to macro, for small code size saving on ARM and on Coldfire color, only finish DC decode on greyscale targets if decoding luma channel.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@20874 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 70 insertions, 79 deletions

diff --git a/apps/recorder/jpeg_load.c b/apps/recorder/jpeg_load.c
index 99ab611..555f60d 100644
--- a/apps/recorder/jpeg_load.c
+++ b/apps/recorder/jpeg_load.c
@@ -1675,84 +1675,74 @@ static const int extend_offset[16] = /* entry n is (-1 << n) + 1 */
 #endif
 
 /* Decode a single value */
-INLINE int huff_decode_dc(struct jpeg *p_jpeg, struct derived_tbl* tbl)
-{
-    int nb, look, s, r;
-
-    check_bit_buffer(p_jpeg, HUFF_LOOKAHEAD);
-    look = peek_bits(p_jpeg, HUFF_LOOKAHEAD);
-    if ((nb = tbl->look_nbits[look]) != 0)
-    {
-        drop_bits(p_jpeg, nb);
-        s = tbl->look_sym[look];
-        check_bit_buffer(p_jpeg, s);
-        r = get_bits(p_jpeg, s);
-        s = HUFF_EXTEND(r, s);
-    }
-    else
-    {   /*  slow_DECODE(s, HUFF_LOOKAHEAD+1)) < 0); */
-        long code;
-        nb=HUFF_LOOKAHEAD+1;
-        check_bit_buffer(p_jpeg, nb);
-        code = get_bits(p_jpeg, nb);
-        while (code > tbl->maxcode[nb])
-        {
-            code <<= 1;
-            check_bit_buffer(p_jpeg, 1);
-            code |= get_bits(p_jpeg, 1);
-            nb++;
-        }
-        if (nb > 16) /* error in Huffman */
-        {
-            s=0; /* fake a zero, this is most safe */
-        }
-        else
-        {
-            s = tbl->pub[16 + tbl->valptr[nb] +
-                ((int) (code - tbl->mincode[nb]))];
-            check_bit_buffer(p_jpeg, s);
-            r = get_bits(p_jpeg, s);
-            s = HUFF_EXTEND(r, s);
-        }
-    } /* end slow decode */
-    return s;
+#define huff_decode_dc(p_jpeg, tbl, s, r) \
+{ \
+    int nb, look; \
+\
+    check_bit_buffer((p_jpeg), HUFF_LOOKAHEAD); \
+    look = peek_bits((p_jpeg), HUFF_LOOKAHEAD); \
+    if ((nb = (tbl)->look_nbits[look]) != 0) \
+    { \
+        drop_bits((p_jpeg), nb); \
+        s = (tbl)->look_sym[look]; \
+        check_bit_buffer((p_jpeg), s); \
+        r = get_bits((p_jpeg), s); \
+    } else { \
+        /*  slow_DECODE(s, HUFF_LOOKAHEAD+1)) < 0); */ \
+        long code; \
+        nb=HUFF_LOOKAHEAD+1; \
+        check_bit_buffer((p_jpeg), nb); \
+        code = get_bits((p_jpeg), nb); \
+        while (code > (tbl)->maxcode[nb]) \
+        { \
+            code <<= 1; \
+            check_bit_buffer((p_jpeg), 1); \
+            code |= get_bits((p_jpeg), 1); \
+            nb++; \
+        } \
+        if (nb > 16) /* error in Huffman */ \
+        { \
+            r = 0; s = 0; /* fake a zero, this is most safe */ \
+        } else { \
+            s = (tbl)->pub[16 + (tbl)->valptr[nb] + \
+                ((int) (code - (tbl)->mincode[nb]))]; \
+            check_bit_buffer((p_jpeg), s); \
+            r = get_bits((p_jpeg), s); \
+        } \
+    } /* end slow decode */ \
 }
 
-INLINE int huff_decode_ac(struct jpeg *p_jpeg, struct derived_tbl* tbl)
-{
-    int nb, look, s;
-
-    check_bit_buffer(p_jpeg, HUFF_LOOKAHEAD);
-    look = peek_bits(p_jpeg, HUFF_LOOKAHEAD);
-    if ((nb = tbl->look_nbits[look]) != 0)
-    {
-        drop_bits(p_jpeg, nb);
-        s = tbl->look_sym[look];
-    }
-    else
-    {   /*  slow_DECODE(s, HUFF_LOOKAHEAD+1)) < 0); */
-        long code;
-        nb=HUFF_LOOKAHEAD+1;
-        check_bit_buffer(p_jpeg, nb);
-        code = get_bits(p_jpeg, nb);
-        while (code > tbl->maxcode[nb])
-        {
-            code <<= 1;
-            check_bit_buffer(p_jpeg, 1);
-            code |= get_bits(p_jpeg, 1);
-            nb++;
-        }
-        if (nb > 16) /* error in Huffman */
-        {
-            s=0; /* fake a zero, this is most safe */
-        }
-        else
-        {
-            s = tbl->pub[16 + tbl->valptr[nb] +
-                ((int) (code - tbl->mincode[nb]))];
-        }
-    } /* end slow decode */
-    return s;
+#define huff_decode_ac(p_jpeg, tbl, s) \
+{ \
+    int nb, look; \
+\
+    check_bit_buffer((p_jpeg), HUFF_LOOKAHEAD); \
+    look = peek_bits((p_jpeg), HUFF_LOOKAHEAD); \
+    if ((nb = (tbl)->look_nbits[look]) != 0) \
+    { \
+        drop_bits((p_jpeg), nb); \
+        s = (tbl)->look_sym[look]; \
+    } else { \
+        /*  slow_DECODE(s, HUFF_LOOKAHEAD+1)) < 0); */ \
+        long code; \
+        nb=HUFF_LOOKAHEAD+1; \
+        check_bit_buffer((p_jpeg), nb); \
+        code = get_bits((p_jpeg), nb); \
+        while (code > (tbl)->maxcode[nb]) \
+        { \
+            code <<= 1; \
+            check_bit_buffer((p_jpeg), 1); \
+            code |= get_bits((p_jpeg), 1); \
+            nb++; \
+        } \
+        if (nb > 16) /* error in Huffman */ \
+        { \
+            s = 0; /* fake a zero, this is most safe */ \
+        } else { \
+            s = (tbl)->pub[16 + (tbl)->valptr[nb] + \
+                ((int) (code - (tbl)->mincode[nb]))]; \
+        } \
+    } /* end slow decode */ \
 }
 
 static struct img_part *store_row_jpeg(void *jpeg_args)
@@ -1799,12 +1789,13 @@ static struct img_part *store_row_jpeg(void *jpeg_args)
                 struct derived_tbl* actbl = &p_jpeg->ac_derived_tbls[ti];
 
                 /* Section F.2.2.1: decode the DC coefficient difference */
-                s = huff_decode_dc(p_jpeg, dctbl);
+                huff_decode_dc(p_jpeg, dctbl, s, r);
 
 #ifndef HAVE_LCD_COLOR
                 if (!ci)
 #endif
                 {
+                    s = HUFF_EXTEND(r, s);
 #ifdef HAVE_LCD_COLOR
                     p_jpeg->last_dc_val[ci] += s;
                     /* output it (assumes zag[0] = 0) */
@@ -1821,7 +1812,7 @@ static struct img_part *store_row_jpeg(void *jpeg_args)
                     /* Section F.2.2.2: decode the AC coefficients */
                     for (; k < p_jpeg->k_need[!!ci]; k++)
                     {
-                        s = huff_decode_ac(p_jpeg, actbl);
+                        huff_decode_ac(p_jpeg, actbl, s);
                         r = s >> 4;
                         s &= 15;
                         if (s)
@@ -1851,7 +1842,7 @@ static struct img_part *store_row_jpeg(void *jpeg_args)
                 }
                 for (; k < 64; k++)
                 {
-                    s = huff_decode_ac(p_jpeg, actbl);
+                    huff_decode_ac(p_jpeg, actbl, s);
                     r = s >> 4;
                     s &= 15;