Commit graph

247 commits

Author SHA1 Message Date
Gabe Black
110c59b414 MIPS: Get rid of cruft in the fault classes.
Get rid of Fault classes left over from when this file was copied from Alpha,
and rename ArithmeticOverflowFault to be IntegerOverflowFault and get rid of
the old IntegerOverflowFault stub. The Integer version is what's actually in
the manual, but the Arithmetic version had the implementation.
2011-09-19 06:17:19 -07:00
Gabe Black
7e704c9f51 MIPS: Add constructors to the fault classes. 2011-09-19 06:17:19 -07:00
Gabe Black
27388c0fe0 MIPS: Use the CRTP to streamline the Fault class definitions.
CRTP stands for the curiously recurring template pattern.
2011-09-19 06:17:19 -07:00
Gabe Black
f21ae529fb MIPS: Get rid of #if style config checks in the ISA description. 2011-09-19 06:14:02 -07:00
Gabe Black
4ad36a4684 MIPS: Guard SystemCallFault::invoke consistently.
Make sure it's declared iff it's also defined.
2011-09-19 06:09:15 -07:00
Gabe Black
49967ed268 MIPS: Get rid of the unused (and partially defined) CacheError fault. 2011-09-19 05:53:54 -07:00
Deyuan Guo
bb921b1459 MIPS: Implement gem5/src/arch/mips/remote_gdb.cc.
So a mips-cross-gdb can connect with gem5(MIPS_SE), and do some remote
debugging.

Testing:

Build gem5 for MIPS_SE and make gem5 wait at beginning:
modify "rgdb_wait = -1" to "rgdb_wait = 0" in src/sim/system.cc;
scons build/MIPS_SE/gem5.opt CPU_MODELS=O3CPU
----
Build GDB-7.3 mips-cross:
./configure --target=mips-linux-gnu --prefix=xxx/gdb-7.3-install/
make
make install
----
Run:
./build/MIPS_SE/gem5.opt configs/example/se.py --detailed --caches
./mips-linux-gnu-gdb xxx/gem5/tests/test-progs/hello/bin/mips/linux/hello
(gdb) target remote :7000
(gdb) info registers
(gdb) disassemble
(gdb) si
(gdb) break main
(gdb) c
(gdb) quit
Testing done.
2011-09-10 03:45:25 -07:00
Gabe Black
49a7ed0397 StaticInst: Merge StaticInst and StaticInstBase.
Having two StaticInst classes, one nominally ISA dependent and the other ISA
dependent, has not been historically useful and makes the StaticInst class
more complicated that it needs to be. This change merges StaticInstBase into
StaticInst.
2011-09-09 02:40:11 -07:00
Gabe Black
63a934d152 ISA parser: Define operand types with a ctype directly. 2011-07-05 16:52:15 -07:00
Gabe Black
aade13769f ISA: Use readBytes/writeBytes for all instruction level memory operations. 2011-07-02 22:34:29 -07:00
Deyaun Guo
5aaddc129e mips: fix nmsub and nmadd definitions
the -/+ signs were flipped for nmsub_s, nmsub_d, and nmadd_d
2011-06-22 23:35:21 -04:00
Korey Sewell
59686795e3 mips: mark unaligned access flag as true 2011-06-19 21:43:41 -04:00
Nathan Binkert
2b1aa35e20 scons: rename TraceFlags to DebugFlags 2011-06-02 17:36:21 -07:00
Chander Sudanthi
4bf48a11ef Trace: Allow printing ASIDs and selectively tracing based on user/kernel code.
Debug flags are ExecUser, ExecKernel, and ExecAsid. ExecUser and
ExecKernel are set by default when Exec is specified.  Use minus
sign with ExecUser or ExecKernel to remove user or kernel tracing
respectively.
2011-05-13 17:27:00 -05:00
Nathan Binkert
eddac53ff6 trace: reimplement the DTRACE function so it doesn't use a vector
At the same time, rename the trace flags to debug flags since they
have broader usage than simply tracing.  This means that
--trace-flags is now --debug-flags and --trace-help is now --debug-help
2011-04-15 10:44:32 -07:00
Nathan Binkert
39a055645f includes: sort all includes 2011-04-15 10:44:06 -07:00
Ali Saidi
a679cd917a ARM: Cleanup implementation of ITSTATE and put important code in PCState.
Consolidate all code to handle ITSTATE in the PCState object rather than
touching a variety of structures/objects.
2011-04-04 11:42:28 -05:00
Korey Sewell
e0fdd86fd9 mips: cleanup ISA-specific code
***
(1): get rid of expandForMT function
MIPS is the only ISA that cares about having a piece of ISA state integrate
multiple threads so add constants for MIPS and relieve the other ISAs from having
to define this. Also, InOrder was the only core that was actively calling
this function
* * *
(2): get rid of corespecific type
The CoreSpecific type was used as a proxy to pass in HW specific params to
a MIPS CPU, but since MIPS FS hasnt been touched for awhile, it makes sense
to not force every other ISA to use CoreSpecific as well use a special
reset function to set it. That probably should go in a PowerOn reset fault
 anyway.
2011-03-26 09:23:52 -04:00
Ali Saidi
799c3da8d0 O3: Send instruction back to fetch on squash to seed predecoder correctly. 2011-03-17 19:20:19 -05:00
Gabe Black
579c5f0b65 Spelling: Fix the a spelling error by changing mmaped to mmapped.
There may not be a formally correct spelling for the past tense of mmap, but
mmapped is the spelling Google doesn't try to autocorrect. This makes sense
because it mirrors the past tense of map->mapped and not the past tense of
cape->caped.

--HG--
rename : src/arch/alpha/mmaped_ipr.hh => src/arch/alpha/mmapped_ipr.hh
rename : src/arch/arm/mmaped_ipr.hh => src/arch/arm/mmapped_ipr.hh
rename : src/arch/mips/mmaped_ipr.hh => src/arch/mips/mmapped_ipr.hh
rename : src/arch/power/mmaped_ipr.hh => src/arch/power/mmapped_ipr.hh
rename : src/arch/sparc/mmaped_ipr.hh => src/arch/sparc/mmapped_ipr.hh
rename : src/arch/x86/mmaped_ipr.hh => src/arch/x86/mmapped_ipr.hh
2011-03-01 23:18:47 -08:00
Korey Sewell
e65c15e931 inorder: remove unused isa ops
pass/fail ops were used for testing but arent part of isa
2011-02-12 10:14:26 -05:00
Gabe Black
091a3e6cc0 Fault: Rename sim/fault.hh to fault_fwd.hh to distinguish it from faults.hh.
--HG--
rename : src/sim/fault.hh => src/sim/fault_fwd.hh
2011-02-03 21:47:58 -08:00
Steve Reinhardt
6f1187943c Replace curTick global variable with accessor functions.
This step makes it easy to replace the accessor functions
(which still access a global variable) with ones that access
per-thread curTick values.
2011-01-07 21:50:29 -08:00
Steve Reinhardt
c69d48f007 Make commenting on close namespace brackets consistent.
Ran all the source files through 'perl -pi' with this script:

s|\s*(};?\s*)?/\*\s*(end\s*)?namespace\s*(\S+)\s*\*/(\s*})?|} // namespace $3|;
s|\s*};?\s*//\s*(end\s*)?namespace\s*(\S+)\s*|} // namespace $2\n|;
s|\s*};?\s*//\s*(\S+)\s*namespace\s*|} // namespace $1\n|;

Also did a little manual editing on some of the arch/*/isa_traits.hh files
and src/SConscript.
2011-01-03 14:35:43 -08:00
Gabe Black
672d6a4b98 Style: Replace some tabs with spaces. 2010-12-20 16:24:40 -05:00
Gabe Black
f26051eb1a MIPS: Take advantage of new PCState syntax. 2010-12-08 10:45:14 -08:00
Giacomo Gabrielli
719f9a6d4f O3: Make all instructions that write a misc. register not perform the write until commit.
ARM instructions updating cumulative flags (ARM FP exceptions and saturation
flags) are not serialized.

Added aliases for ARM FP exceptions and saturation flags in FPSCR.  Removed
write accesses to the FP condition codes for most ARM VFP instructions: only
VCMP and VCMPE instructions update the FP condition codes.  Removed a potential
cause of seg. faults in the O3 model for NEON memory macro-ops (ARM).
2010-12-07 16:19:57 -08:00
Gabe Black
8b9b85e92c O3: Make O3 support variably lengthed instructions. 2010-11-15 19:37:03 -08:00
Ali Saidi
cdacbe734a ARM/Alpha/Cpu: Change prefetchs to be more like normal loads.
This change modifies the way prefetches work. They are now like normal loads
that don't writeback a register. Previously prefetches were supposed to call
prefetch() on the exection context, so they executed with execute() methods
instead of initiateAcc() completeAcc(). The prefetch() methods for all the CPUs
are blank, meaning that they get executed, but don't actually do anything.

On Alpha dead cache copy code was removed and prefetches are now normal ops.
They count as executed operations, but still don't do anything and IsMemRef is
not longer set on them.

On ARM IsDataPrefetch or IsInstructionPreftech is now set on all prefetch
instructions. The timing simple CPU doesn't try to do anything special for
prefetches now and they execute with the normal memory code path.
2010-11-08 13:58:22 -06:00
Ali Saidi
0ea794bcf4 sim: Use forward declarations for ports.
Virtual ports need TLB data which means anything touching a file in the arch
directory rebuilds any file that includes system.hh which in everything.
2010-11-08 13:58:22 -06:00
Gabe Black
6f4bd2c1da ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors.
This change is a low level and pervasive reorganization of how PCs are managed
in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about,
the PC and the NPC, and the lsb of the PC signaled whether or not you were in
PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next
micropc, x86 and ARM introduced variable length instruction sets, and ARM
started to keep track of mode bits in the PC. Each CPU model handled PCs in
its own custom way that needed to be updated individually to handle the new
dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack,
the complexity could be hidden in the ISA at the ISA implementation's expense.
Areas like the branch predictor hadn't been updated to handle branch delay
slots or micropcs, and it turns out that had introduced a significant (10s of
percent) performance bug in SPARC and to a lesser extend MIPS. Rather than
perpetuate the problem by reworking O3 again to handle the PC features needed
by x86, this change was introduced to rework PC handling in a more modular,
transparent, and hopefully efficient way.


PC type:

Rather than having the superset of all possible elements of PC state declared
in each of the CPU models, each ISA defines its own PCState type which has
exactly the elements it needs. A cross product of canned PCState classes are
defined in the new "generic" ISA directory for ISAs with/without delay slots
and microcode. These are either typedef-ed or subclassed by each ISA. To read
or write this structure through a *Context, you use the new pcState() accessor
which reads or writes depending on whether it has an argument. If you just
want the address of the current or next instruction or the current micro PC,
you can get those through read-only accessors on either the PCState type or
the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the
move away from readPC. That name is ambiguous since it's not clear whether or
not it should be the actual address to fetch from, or if it should have extra
bits in it like the PAL mode bit. Each class is free to define its own
functions to get at whatever values it needs however it needs to to be used in
ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the
PC and into a separate field like ARM.

These types can be reset to a particular pc (where npc = pc +
sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as
appropriate), printed, serialized, and compared. There is a branching()
function which encapsulates code in the CPU models that checked if an
instruction branched or not. Exactly what that means in the context of branch
delay slots which can skip an instruction when not taken is ambiguous, and
ideally this function and its uses can be eliminated. PCStates also generally
know how to advance themselves in various ways depending on if they point at
an instruction, a microop, or the last microop of a macroop. More on that
later.

Ideally, accessing all the PCs at once when setting them will improve
performance of M5 even though more data needs to be moved around. This is
because often all the PCs need to be manipulated together, and by getting them
all at once you avoid multiple function calls. Also, the PCs of a particular
thread will have spatial locality in the cache. Previously they were grouped
by element in arrays which spread out accesses.


Advancing the PC:

The PCs were previously managed entirely by the CPU which had to know about PC
semantics, try to figure out which dimension to increment the PC in, what to
set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction
with the PC type itself. Because most of the information about how to
increment the PC (mainly what type of instruction it refers to) is contained
in the instruction object, a new advancePC virtual function was added to the
StaticInst class. Subclasses provide an implementation that moves around the
right element of the PC with a minimal amount of decision making. In ISAs like
Alpha, the instructions always simply assign NPC to PC without having to worry
about micropcs, nnpcs, etc. The added cost of a virtual function call should
be outweighed by not having to figure out as much about what to do with the
PCs and mucking around with the extra elements.

One drawback of making the StaticInsts advance the PC is that you have to
actually have one to advance the PC. This would, superficially, seem to
require decoding an instruction before fetch could advance. This is, as far as
I can tell, realistic. fetch would advance through memory addresses, not PCs,
perhaps predicting new memory addresses using existing ones. More
sophisticated decisions about control flow would be made later on, after the
instruction was decoded, and handed back to fetch. If branching needs to
happen, some amount of decoding needs to happen to see that it's a branch,
what the target is, etc. This could get a little more complicated if that gets
done by the predecoder, but I'm choosing to ignore that for now.


Variable length instructions:

To handle variable length instructions in x86 and ARM, the predecoder now
takes in the current PC by reference to the getExtMachInst function. It can
modify the PC however it needs to (by setting NPC to be the PC + instruction
length, for instance). This could be improved since the CPU doesn't know if
the PC was modified and always has to write it back.


ISA parser:

To support the new API, all PC related operand types were removed from the
parser and replaced with a PCState type. There are two warts on this
implementation. First, as with all the other operand types, the PCState still
has to have a valid operand type even though it doesn't use it. Second, using
syntax like PCS.npc(target) doesn't work for two reasons, this looks like the
syntax for operand type overriding, and the parser can't figure out if you're
reading or writing. Instructions that use the PCS operand (which I've
consistently called it) need to first read it into a local variable,
manipulate it, and then write it back out.


Return address stack:

The return address stack needed a little extra help because, in the presence
of branch delay slots, it has to merge together elements of the return PC and
the call PC. To handle that, a buildRetPC utility function was added. There
are basically only two versions in all the ISAs, but it didn't seem short
enough to put into the generic ISA directory. Also, the branch predictor code
in O3 and InOrder were adjusted so that they always store the PC of the actual
call instruction in the RAS, not the next PC. If the call instruction is a
microop, the next PC refers to the next microop in the same macroop which is
probably not desirable. The buildRetPC function advances the PC intelligently
to the next macroop (in an ISA specific way) so that that case works.


Change in stats:

There were no change in stats except in MIPS and SPARC in the O3 model. MIPS
runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could
likely be improved further by setting call/return instruction flags and taking
advantage of the RAS.


TODO:

Add != operators to the PCState classes, defined trivially to be !(a==b).
Smooth out places where PCs are split apart, passed around, and put back
together later. I think this might happen in SPARC's fault code. Add ISA
specific constructors that allow setting PC elements without calling a bunch
of accessors. Try to eliminate the need for the branching() function. Factor
out Alpha's PAL mode pc bit into a separate flag field, and eliminate places
where it's blindly masked out or tested in the PC.
2010-10-31 00:07:20 -07:00
Gabe Black
29676286c8 ISA: Simplify various implementations of completeAcc. 2010-10-22 00:23:19 -07:00
Gabe Black
b289966a78 Mem: Reclaim some request flags used by MIPS for alignment checking.
These flags were being used to identify what alignment a request needed, but
the same information is available using the request size. This change also
eliminates the isMisaligned function. If more complicated alignment checks are
needed, they can be signaled using the ASI_BITS space in the flags vector like
is currently done with ARM.
2010-10-16 00:00:54 -07:00
Gabe Black
ab9f062166 GetArgument: Rework getArgument so that X86_FS compiles again.
When no size is specified for an argument, push the decision about what size
to use into the ISA by passing a size of -1.
2010-10-15 23:57:06 -07:00
Ali Saidi
518b5e5b1c Debug: Implement getArgument() and function skipping for ARM.
In the process make add skipFuction() to handle isa specific function skipping
instead of ifdefs and other ugliness. For almost all ABIs, 64 bit arguments can
only start in even registers.  Size is now passed to getArgument() so that 32
bit systems can make decisions about register selection for 64 bit arguments.
The number argument is now passed by reference because getArgument() will need
to change it based on the size of the argument and the current argument number.

For ARM, if the argument number is odd and a 64-bit register is requested the
number must first be incremented to because all 64 bit arguments are passed
in an even argument register. Then the number will be incremented again to
access both halves of the argument.
2010-10-01 16:02:46 -05:00
Gabe Black
6833ca7eed Faults: Pass the StaticInst involved, if any, to a Fault's invoke method.
Also move the "Fault" reference counted pointer type into a separate file,
sim/fault.hh. It would be better to name this less similarly to sim/faults.hh
to reduce confusion, but fault.hh matches the name of the type. We could change
Fault to FaultPtr to match other pointer types, and then changing the name of
the file would make more sense.
2010-09-13 19:26:03 -07:00
Nathan Binkert
afafaf1dcb style: fix sorting of includes and whitespace in some files 2010-09-10 14:58:04 -07:00
Min Kyu Jeong
e1168e72ca ARM: Fixed register flattening logic (FP_Base_DepTag was set too low)
When decoding a srs instruction, invalid mode encoding returns invalid instruction.
This can happen when garbage instructions are fetched from mispredicted path
2010-08-25 19:10:43 -05:00
Gabe Black
943c171480 ISA: Get rid of old, unused utility functions cluttering up the ISAs. 2010-08-23 16:14:20 -07:00
Ali Saidi
f2642e2055 Loader: Make the load address mask be a parameter of the system rather than a constant.
This allows one two different OS requirements for the same ISA to be handled.
Some OSes are compiled for a virtual address and need to be loaded into physical
memory that starts at address 0, while other bare metal tools generate
images that start at address 0.
2010-08-23 11:18:39 -05:00
Steve Reinhardt
f064aa3060 sim: revamp unserialization procedure
Replace direct call to unserialize() on each SimObject with a pair of
calls for better control over initialization in both ckpt and non-ckpt
cases.

If restoring from a checkpoint, loadState(ckpt) is called on each
SimObject.  The default implementation simply calls unserialize() if
there is a corresponding checkpoint section, so we get backward
compatibility for existing objects.  However, objects can override
loadState() to get other behaviors, e.g., doing other programmed
initializations after unserialize(), or complaining if no checkpoint
section is found.  (Note that the default warning for a missing
checkpoint section is now gone.)

If not restoring from a checkpoint, we call the new initState() method
on each SimObject instead.  This provides a hook for state
initializations that are only required when *not* restoring from a
checkpoint.

Given this new framework, do some cleanup of LiveProcess subclasses
and X86System, which were (in some cases) emulating initState()
behavior in startup via a local flag or (in other cases) erroneously
doing initializations in startup() that clobbered state loaded earlier
by unserialize().
2010-08-17 05:17:06 -07:00
Nathan Binkert
86a93fe7b9 stats: only consider a formula initialized if there is a formula 2010-06-15 01:18:36 -07:00
Steve Reinhardt
d0af5e9df6 More minor gdb-related cleanup.
Found several more stale includes and forward decls.
2010-06-03 19:41:34 -07:00
Nathan Binkert
e99828b06a tick: rename Clock namespace to SimClock 2010-04-15 16:24:12 -07:00
Steve Reinhardt
4d77ea7a57 cpu: fix exec tracing memory corruption bug
Accessing traceData (to call setAddress() and/or setData())
after initiating a timing translation was causing crashes,
since a failed translation could delete the traceData
object before returning.

It turns out that there was never a need to access traceData
after initiating the translation, as the traced data was
always available earlier; this ordering was merely
historical.  Furthermore, traceData->setAddress() and
traceData->setData() were being called both from the CPU
model and the ISA definition, often redundantly.

This patch standardizes all setAddress and setData calls
for memory instructions to be in the CPU models and not
in the ISA definition.  It also moves those calls above
the translation calls to eliminate the crashes.
2010-03-23 08:50:57 -07:00
Timothy M. Jones
29e8bcead5 O3PCU: Split loads and stores that cross cache line boundaries.
When each load or store is sent to the LSQ, we check whether it will cross a
cache line boundary and, if so, split it in two. This creates two TLB
translations and two memory requests. Care has to be taken if the first
packet of a split load is sent but the second blocks the cache. Similarly,
for a store, if the first packet cannot be sent, we must store the second
one somewhere to retry later.

This modifies the LSQSenderState class to record both packets in a split
load or store.

Finally, a new const variable, HasUnalignedMemAcc, is added to each ISA
to indicate whether unaligned memory accesses are allowed. This is used
throughout the changed code so that compiler can optimise away code dealing
with split requests for ISAs that don't need them.
2010-02-12 19:53:20 +00:00
Matt DeVuyst
18dc80e07b MIPS: Beef up process initialization. 2009-12-31 15:30:51 -05:00
Gabe Black
ecaa7070e6 MIPS: Implement the SE mode version of rdhwr. 2009-12-31 15:30:51 -05:00
Gabe Black
c70f3c93af MIPS: Fix decoding of the rdhwr instruction. 2009-12-31 15:30:51 -05:00
Gabe Black
134937b594 MIPS: Implement the set_thread_area system call. 2009-12-31 15:30:50 -05:00