Improve 386 portability of aes-586.pl.

#

# Version 4.3 implements switch between compact and non-compact block

# functions in AES_cbc_encrypt depending on how much data was asked

# to process in one stroke.

# to be processed in one stroke.

#

######################################################################

# Timing attacks are classified in two classes: synchronous when

# attacker consciously initiates cryptographic operation and collects

# timing data of various character afterwards, and asynchronous when

# timing. But note that *if* plain-text was concealed in such way that

# input to block function is distributed *uniformly*, then attack

# wouldn't apply. Now note that some encryption modes, most notably

# CBC, do masks the plain-text in this exact way [secure cipher output

# CBC, do mask the plain-text in this exact way [secure cipher output

# is distributed uniformly]. Yes, one still might find input that

# would reveal the information about given key, but if amount of

# candidate inputs to be tried is larger than amount of possible key

	&pushf	();			# kludge, never executed

    &set_label("slow_enc_tail",16);

	&emms	();

	&emms	()	if (!$x86only);

	&mov	($key eq "edi"? $key:"",$s3);	# load out to edi

	&mov	($s1,16);

	&sub	($s1,$s2);