The branch master has been updated
       via  eec5cb82df9dbe5dea8ebf7c32e8ee93d35f5c82 (commit)
      from  630b05a0ec207b5e96940175e015b34cc3c4c5fb (commit)


- Log -----------------------------------------------------------------
commit eec5cb82df9dbe5dea8ebf7c32e8ee93d35f5c82
Author: Rich Salz <rs...@akamai.com>
Date:   Thu Aug 10 11:16:42 2017 -0400

    Add optimized assembler question

-----------------------------------------------------------------------

Summary of changes:
 docs/faq-4-build.txt | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/docs/faq-4-build.txt b/docs/faq-4-build.txt
index efa754f..e60d788 100644
--- a/docs/faq-4-build.txt
+++ b/docs/faq-4-build.txt
@@ -1,5 +1,19 @@
 Questions on Building and Testing OpenSSL
 
+* Does OpenSSL use AES-NI or other speedups?
+
+The short answer is yes, unless you configure with "no-asm."
+
+What OpenSSL does is not obvious.  The INSTALL document talks about the
+no-asm configuration option.  Details about what the assembler code does
+in terms of optimization are only available by reading the source code
+comments in the various Perl files that generate the assembler, mostly.
+
+On x86, the assembly code uses the CPUID instruction (see the
+OPENSSL_ia32cap.pod manpage) to determine if various instructions (AES,
+SSE, MMX, etc) are available and will use them if so.  For other processors,
+similar tests are performed if at all possible.
+
 * Why does Clang sanitizer give warnings?
 
 You need to build with -DPEDANTIC to run sanitized tests, otherwise
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