RFR: Extend substitution guards to receive Architecture

[Doug Simon]

SubstitutionGuard.java:

+  * <li><code>Guard(Architecture)</code>
+  * <li><code>Guard()</code> (an implicit constructor is OK as well)

We prefer to use {@code ...} instead of <code>...</code>

Otherwise, looks good to me.

-Doug


> On Nov 20, 2014, at 11:55 PM, Igor Veresov <igor.veresov at oracle.com> wrote:
> 
> - adds ability for substitution guards to have a constructor that has Architecture as an argument
> - added extra flags enum to AMD64 to drive code emission features (currently contains UseCountLeadingZerosInstruction and UseCountTrailingZerosInstruction)
> - moved lzcnt/tzcnt nodes and substitutions to com.oracle.graal.replacements.amd64
> 
> Webrev: http://cr.openjdk.java.net/~iveresov/subst-guard/webrev.00/
> 
> Thanks!
> igor