X-Git-Url: https://wimlib.net/git/?p=wimlib;a=blobdiff_plain;f=src%2Flzx-compress.c;h=bc50a858bc9b62cf26d9d1b03d7b822591a1eb33;hp=4c89b7d9768e1110b5e54f71580ba6ec0a592327;hb=bcf3ccecc8071729f34fe5b393fab64fc02e3d47;hpb=b749dafe952fc5c8b54be6670c20740ee8150169

diff --git a/src/lzx-compress.c b/src/lzx-compress.c
index 4c89b7d9..bc50a858 100644
--- a/src/lzx-compress.c
+++ b/src/lzx-compress.c
@@ -659,9 +659,9 @@ lzx_make_huffman_codes(const struct lzx_freqs *freqs,
  *
  * @os:
  *	The bitstream to which to write the match.
- * @block_type:
- *	The type of the LZX block (LZX_BLOCKTYPE_ALIGNED or
- *	LZX_BLOCKTYPE_VERBATIM)
+ * @ones_if_aligned
+ *	A mask of all ones if the block is of type LZX_BLOCKTYPE_ALIGNED,
+ *	otherwise 0.
  * @match:
  *	The match data.
  * @codes:
@@ -669,7 +669,7 @@ lzx_make_huffman_codes(const struct lzx_freqs *freqs,
  *	and aligned offset Huffman codes for the current LZX compressed block.
  */
 static void
-lzx_write_match(struct lzx_output_bitstream *os, int block_type,
+lzx_write_match(struct lzx_output_bitstream *os, unsigned ones_if_aligned,
 		struct lzx_item match, const struct lzx_codes *codes)
 {
 	unsigned match_len_minus_2 = match.data & 0xff;
@@ -719,7 +719,7 @@ lzx_write_match(struct lzx_output_bitstream *os, int block_type,
 
 	num_extra_bits = lzx_get_num_extra_bits(position_slot);
 
-	if ((block_type == LZX_BLOCKTYPE_ALIGNED) && (num_extra_bits >= 3)) {
+	if ((num_extra_bits & ones_if_aligned) >= 3) {
 
 		/* Aligned offset blocks: The low 3 bits of the position footer
 		 * are Huffman-encoded using the aligned offset code.  The
@@ -948,12 +948,14 @@ lzx_write_items(struct lzx_output_bitstream *os, int block_type,
 		const struct lzx_item items[], u32 num_items,
 		const struct lzx_codes *codes)
 {
+	unsigned ones_if_aligned = 0U - (block_type == LZX_BLOCKTYPE_ALIGNED);
+
 	for (u32 i = 0; i < num_items; i++) {
 		/* The high bit of the 32-bit intermediate representation
 		 * indicates whether the item is an actual LZ-style match (1) or
 		 * a literal byte (0).  */
 		if (items[i].data & 0x80000000)
-			lzx_write_match(os, block_type, items[i], codes);
+			lzx_write_match(os, ones_if_aligned, items[i], codes);
 		else
 			lzx_write_literal(os, items[i].data, codes);
 	}
@@ -1461,7 +1463,7 @@ lzx_repsearch(const u8 * const strptr, const u32 bytes_remaining,
 }
 
 /*
- * lzx_choose_near_optimal_match() -
+ * lzx_choose_near_optimal_item() -
  *
  * Choose an approximately optimal match or literal to use at the next position
  * in the string, or "window", being LZ-encoded.
@@ -1622,17 +1624,21 @@ lzx_choose_near_optimal_item(struct lzx_compressor *c)
 		}
 
 		do {
+			u32 cost;
 			unsigned len_header;
 			unsigned main_symbol;
-			u32 cost;
 
 			cost = position_cost;
 
-			len_header = min(len - LZX_MIN_MATCH_LEN, LZX_NUM_PRIMARY_LENS);
+			if (len - LZX_MIN_MATCH_LEN < LZX_NUM_PRIMARY_LENS) {
+				len_header = len - LZX_MIN_MATCH_LEN;
+			} else {
+				len_header = LZX_NUM_PRIMARY_LENS;
+				cost += c->costs.len[len - LZX_MIN_MATCH_LEN - LZX_NUM_PRIMARY_LENS];
+			}
+
 			main_symbol = ((position_slot << 3) | len_header) + LZX_NUM_CHARS;
 			cost += c->costs.main[main_symbol];
-			if (len_header == LZX_NUM_PRIMARY_LENS)
-				cost += c->costs.len[len - LZX_MIN_MATCH_LEN - LZX_NUM_PRIMARY_LENS];
 
 			optimum[len].queue = queue;
 			optimum[len].prev.link = 0;
@@ -1825,22 +1831,25 @@ lzx_choose_near_optimal_item(struct lzx_compressor *c)
 		have_position_cost:
 
 			do {
+				u32 cost;
 				unsigned len_header;
 				unsigned main_symbol;
-				u32 cost;
 
 				cost = position_cost;
 
-				len_header = min(len - LZX_MIN_MATCH_LEN,
-						 LZX_NUM_PRIMARY_LENS);
-				main_symbol = ((position_slot << 3) | len_header) +
-						LZX_NUM_CHARS;
-				cost += c->costs.main[main_symbol];
-				if (len_header == LZX_NUM_PRIMARY_LENS) {
+				if (len - LZX_MIN_MATCH_LEN < LZX_NUM_PRIMARY_LENS) {
+					len_header = len - LZX_MIN_MATCH_LEN;
+				} else {
+					len_header = LZX_NUM_PRIMARY_LENS;
 					cost += c->costs.len[len -
 							LZX_MIN_MATCH_LEN -
 							LZX_NUM_PRIMARY_LENS];
 				}
+
+				main_symbol = ((position_slot << 3) | len_header) +
+						LZX_NUM_CHARS;
+				cost += c->costs.main[main_symbol];
+
 				if (cost < optimum[cur_pos + len].cost) {
 					if (position_slot < LZX_NUM_RECENT_OFFSETS) {
 						optimum[cur_pos + len].queue = optimum[cur_pos].queue;