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authorArne Schwabe <arne@rfc2549.org>2012-04-16 19:21:14 +0200
committerArne Schwabe <arne@rfc2549.org>2012-04-16 19:21:14 +0200
commit3e4d8f433239c40311037616b1b8833a06651ae0 (patch)
tree98ab7fce0d011d34677b0beb762d389cb5c39199 /openssl/crypto/bn/asm/README
Initial import
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+<OBSOLETE>
+
+All assember in this directory are just version of the file
+crypto/bn/bn_asm.c.
+
+Quite a few of these files are just the assember output from gcc since on
+quite a few machines they are 2 times faster than the system compiler.
+
+For the x86, I have hand written assember because of the bad job all
+compilers seem to do on it. This normally gives a 2 time speed up in the RSA
+routines.
+
+For the DEC alpha, I also hand wrote the assember (except the division which
+is just the output from the C compiler pasted on the end of the file).
+On the 2 alpha C compilers I had access to, it was not possible to do
+64b x 64b -> 128b calculations (both long and the long long data types
+were 64 bits). So the hand assember gives access to the 128 bit result and
+a 2 times speedup :-).
+
+There are 3 versions of assember for the HP PA-RISC.
+
+pa-risc.s is the origional one which works fine and generated using gcc :-)
+
+pa-risc2W.s and pa-risc2.s are 64 and 32-bit PA-RISC 2.0 implementations
+by Chris Ruemmler from HP (with some help from the HP C compiler).
+
+</OBSOLETE>