aboutsummaryrefslogtreecommitdiffstats
path: root/crypto/bn/asm/README
diff options
context:
space:
mode:
Diffstat (limited to 'crypto/bn/asm/README')
-rw-r--r--crypto/bn/asm/README30
1 files changed, 30 insertions, 0 deletions
diff --git a/crypto/bn/asm/README b/crypto/bn/asm/README
new file mode 100644
index 0000000000..d93fbff77f
--- /dev/null
+++ b/crypto/bn/asm/README
@@ -0,0 +1,30 @@
+All assember in this directory are just version of the file
+crypto/bn/bn_mulw.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 :-).
+
+The x86xxxx.obj files are the assembled version of x86xxxx.asm files.
+I had such a hard time finding a macro assember for Microsoft, I decided to
+include the object file to save others the hassle :-).
+
+I have also included uu encoded versions of the .obj incase they get
+trashed.
+
+There are 2 versions of assember for the HP PA-RISC.
+pa-risc.s is the origional one which works fine.
+pa-risc2.s is a new version that often generates warnings but if the
+tests pass, it gives performance that is over 2 times faster than
+pa-risc.s.
+Both were generated using gcc :-)