Small tidy up of previous patch

[stockfish] / Readme.txt

diff --git a/Readme.txt b/Readme.txt
index dc76d74227862c7bde9ddb643ad37775358568b6..1a3713985e7cec3e47746503892284cd518f4c64 100644 (file)
--- a/Readme.txt
+++ b/Readme.txt
@@ -45,7 +45,6 @@ PolyGlot documentation.  The book file can be selected by setting the
 UCI parameter "Book File".\r
 \r
 \r
-\r
 4. Compiling it yourself\r
 ------------------------\r
 \r
@@ -54,27 +53,18 @@ Stockfish directly from the source code with the included Makefile.
 The exception is computer with big-endian CPUs, like PowerPC\r
 Macintoshes. Some of the bitboard routines in the current version of\r
 Stockfish are endianness-sensitive, and won't work on a big-endian CPU.\r
-Ensuring that the line with #define USE_32BIT_ATTACKS" near the top\r
-of bitboard.h is commented out should solve this problem.\r
-Commenting out the line with "#define USE_32BIT_ATTACKS" near the\r
-\r
-There is also a problem with compiling Stockfish on certain 64-bit\r
-systems, regardless of the endianness.  If Stockfish segfaults\r
-immediately after startup, try to comment out the line with\r
-"#define USE_FOLDED_BITSCAN" near the beginning of bitboard.h and\r
-recompile.\r
-\r
-Finally, even if Stockfish does work without any changes on your\r
-computer, it might be possible to improve the performance by changing\r
-some of the #define directives in bitboard.h.  The default settings\r
-are optimized for 64-bit CPUs.  On 32-bit CPUs, it is probably better\r
-to switch on USE_32BIT_ATTACKS, and to use BITCOUNT_SWAR_32 instead of\r
-BITCOUNT_SWAR_64.  For computers with very little memory (like\r
-handheld devices), it is possible to conserve memory by defining\r
-USE_COMPACT_ROOK_ATTACKS.\r
-\r
-\r
-6. Terms of use\r
+\r
+Stockfish has POPCNT instruction runtime detection and support. This can\r
+give an extra speed on Core i7 or similar systems. To enable this feature\r
+(disabled by default) simply uncomment #define USE_POPCNT in bitcount.h\r
+before to compile.\r
+\r
+On 64 bit Unix-like systems the 'bsfq' assembly instruction will be used\r
+for bit counting. Detection is automatic at compile time, but in case you\r
+experience compile problems you can comment out #define USE_BSFQ line in types.h\r
+\r
+\r
+5. Terms of use\r
 ---------------\r
 \r
 Stockfish is free, and distributed under the GNU General Public License\r
@@ -93,7 +83,7 @@ For full details, read the copy of the GPL found in the file named
 Copying.txt.\r
 \r
 \r
-7. Feedback\r
+6. Feedback\r
 -----------\r
 \r
 The author's e-mail address is mcostalba@gmail.com\r