cpu: clean up architectural register classification

Move from a poorly documented scheme where the mapping
of unified architectural register indices to register
classes is hardcoded all over to one where there's an
enum for the register classes and a function that
encapsulates the mapping.
cpu/inorder: merge register class enums

The previous patch introduced a RegClass enum to clean
up register classification.  The inorder model already
had an equivalent enum (RegType) that was used internally.
This patch replaces RegType with RegClass to get rid
of the now-redundant code.
cpu/o3: clean up physical register file

No need for PhysRegFile to be a template class, or
have a pointer back to the CPU.  Also made some methods
for checking the physical register type (int vs. float)
based on the phys reg index, which will come in handy later.
cpu/o3: clean up scoreboard object

It had a bunch of fields (and associated constructor
parameters) thet it didn't really use, and the array
initialization was needlessly verbose.

Also just hardwired the getReg() method to aleays
return true for misc regs, rather than having an array
of bits that we always kept marked as ready.
isa: clean up register constants

Clean up and add some consistency to the *_Base_DepTag
constants as well as some related register constants:
- Get rid of NumMiscArchRegs, TotalArchRegs, and TotalDataRegs
  since they're never used and not always defined
- Set FP_Base_DepTag = NumIntRegs when possible (i.e.,
  every case except x86)
- Set Ctrl_Base_DepTag = FP_Base_DepTag + NumFloatRegs
  (this was true before, but wasn't always expressed
  that way)
- Drastically reduce the number of arbitrary constants
  appearing in these calculations
cpu: rename *_DepTag constants to *_Reg_Base

Make these names more meaningful.

Specifically, made these substitutions:

s/FP_Base_DepTag/FP_Reg_Base/g;
s/Ctrl_Base_DepTag/Misc_Reg_Base/g;
s/Max_DepTag/Max_Reg_Index/g;
cpu/o3: clean up rename map and free list

Restructured rename map and free list to clean up some
extraneous code and separate out common code that can
be reused across different register classes (int and fp
at this point).  Both components now consist of a set
of Simple* objects that are stand-alone rename map &
free list for each class, plus a Unified* object that
presents a unified interface across all register
classes and then redirects accesses to the appropriate
Simple* object as needed.

Moved free list initialization to PhysRegFile to better
isolate knowledge of physical register index mappings
to that class (and remove the need to pass a number
of parameters to the free list constructor).

Causes a small change to these stats:
  cpu.rename.int_rename_lookups
  cpu.rename.fp_rename_lookups
because they are now categorized on a per-operand basis
rather than a per-instruction basis.
That is, an instruction with mixed fp/int/misc operand
types will have each operand categorized independently,
where previously the lookup was categorized based on
the instruction type.
cpu: add a condition-code register class

Add a third register class for condition codes,
in parallel with the integer and FP classes.
No ISAs use the CC class at this point though.
arch/x86: add support for explicit CC register file

Convert condition code registers from being specialized
("pseudo") integer registers to using the recently
added CC register class.

Nilay Vaish also contributed to this patch.
scons: fix minor update-ref bug in regressions

In the unusual case that regressions are run with --update-ref
when there is no existing regression output, scons gets
confused because it depends on stats.txt to trigger the
update, but it has no indication that running the test will
generate the stats.txt file.  (In the typical case where
stats.txt already exists, scons doesn't care about where
it came from.)

It's easy to fix this just by adding the stats.txt file
to the target list for the test action.
ruby: eliminate non-determinism from ruby.stats output

Get rid of non-deterministic "stats" in ruby.stats output
such as time & date of run, elapsed & CPU time used,
and memory usage.  These values cause spurious
miscomparisons when looking at output diffs (though
they don't affect regressions, since the regressions
pass/fail status currently ignores ruby.stats entirely).

Most of this information is already captured in other
places (time & date in stdout, elapsed time & mem usage
in stats.txt), where the regression script is smart
enough to filter it out.  It seems easier to get rid of
the redundant output rather than teaching the
regression tester to ignore the same information in
two different places.
test: update stats

Update stats for recent changes.  Mostly minor changes
in register access stats due to addition of new cc
register type and slightly different (and more accurate)
classification of int vs. fp register accesses.
kvm: Fix latency calculation of IPR accesses

When handling IPR accesses in doMMIOAccess, the KVM CPU used
clockEdge() to convert between cycles and ticks. This is incorrect
since doMMIOAccess is supposed to return a latency in ticks rather
than when the access is done. This changeset fixes this issue by
returning clockPeriod() * ipr_delay instead.
build: Enable color diagnostics in clang by preserving TERM.
dev: Allow additional UART interrupts to be set

This patch allows setting a few additional interrupts for status
changes that should never occur.
config: Fix memtest example script
arm, config: Fix a small issue with the dtb file being specified
build: Place proto output in the same directory, also for EXTRAS

This patch changes the ProtoBuf builder such that the generated source
and header is placed in the build directory of the proto file. This
was previously not the case for the directories included as EXTRAS. To
make this work, we also ensure that the build directory for the EXTRAS
are added to the include path (which does not seem to automatically be
the case).
mem: Make MemoryAccess flag more verbose

This patch extends the MemoryAccess debug flag to report who sent the
requests and the cacheability.
cpu: Fix O3 uncacheable load that is replayed but misses the TLB

This change fixes an issue in the O3 CPU where an uncachable instruction
is attempted to be executed before it reaches the head of the ROB. It is
determined to be uncacheable, and is replayed, but a PanicFault is attached
to the instruction to make sure that it is properly executed before
committing. If the TLB entry it was using is replaced in the interveaning
time, the TLB returns a delayed translation when the load is replayed at
the head of the ROB, however the LSQ code can't differntiate between the
old fault and the new one. If the translation isn't complete it can't
be faulting, so clear the fault.