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path: root/src/cpu/base_dyn_inst.hh
AgeCommit message (Collapse)Author
2013-10-15cpu: add a condition-code register classYasuko Eckert
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.
2013-07-18mem: Set the cache line size on a system levelAndreas Hansson
This patch removes the notion of a peer block size and instead sets the cache line size on the system level. Previously the size was set per cache, and communicated through the interconnect. There were plenty checks to ensure that everyone had the same size specified, and these checks are now removed. Another benefit that is not yet harnessed is that the cache line size is now known at construction time, rather than after the port binding. Hence, the block size can be locally stored and does not have to be queried every time it is used. A follow-on patch updates the configuration scripts accordingly.
2012-06-05O3: Clean up the O3 structures and try to pack them a bit better.Ali Saidi
DynInst is extremely large the hope is that this re-organization will put the most used members close to each other.
2012-06-05sim: Remove FastAllocAli Saidi
While FastAlloc provides a small performance increase (~1.5%) over regular malloc it isn't thread safe. After removing FastAlloc and using tcmalloc I've seen a performance increase of 12% over libc malloc when running twolf for ARM.
2012-03-19gcc: Clean-up of non-C++0x compliant code, first stepsAndreas Hansson
This patch cleans up a number of minor issues aiming to get closer to compliance with the C++0x standard as interpreted by gcc and clang (compile with std=c++0x and -pedantic-errors). In particular, the patch cleans up enums where the last item was succeded by a comma, namespaces closed by a curcly brace followed by a semi-colon, and the use of the GNU-extension typeof (replaced by templated functions). It does not address variable-length arrays, zero-size arrays, anonymous structs, range expressions in switch statements, and the use of long long. The generated CPU code also has a large number of issues that remain to be fixed, mainly related to overflows in implicit constant conversion (due to shifts).
2012-03-09CheckerCPU: Make CheckerCPU runtime selectable instead of compile selectableGeoffrey Blake
Enables the CheckerCPU to be selected at runtime with the --checker option from the configs/example/fs.py and configs/example/se.py configuration files. Also merges with the SE/FS changes.
2012-02-24CPU: Round-two unifying instr/data CPU ports across modelsAndreas Hansson
This patch continues the unification of how the different CPU models create and share their instruction and data ports. Most importantly, it forces every CPU to have an instruction and a data port, and gives these ports explicit getters in the BaseCPU (getDataPort and getInstPort). The patch helps in simplifying the code, make assumptions more explicit, andfurther ease future patches related to the CPU ports. The biggest changes are in the in-order model (that was not modified in the previous unification patch), which now moves the ports from the CacheUnit to the CPU. It also distinguishes the instruction fetch and load-store unit from the rest of the resources, and avoids the use of indices and casting in favour of keeping track of these two units explicitly (since they are always there anyways). The atomic, timing and O3 model simply return references to their already existing ports.
2012-02-12mem: Add a master ID to each request object.Ali Saidi
This change adds a master id to each request object which can be used identify every device in the system that is capable of issuing a request. This is part of the way to removing the numCpus+1 stats in the cache and replacing them with the master ids. This is one of a series of changes that make way for the stats output to be changed to python.
2012-02-07Faults: Turn off arch/faults.hhGabe Black
Because there are no longer architecture independent but specialized functions in arch/XXX/faults.hh, code that isn't using the faults from a particular ISA no longer needs to be able to include them through the switching header file arch/faults.hh. By removing that header file (arch/faults.hh), the potential interface between ISA code and non ISA code is narrowed.
2012-01-31Merge with head, hopefully the last time for this batch.Gabe Black
2012-01-31CheckerCPU: Re-factor CheckerCPU to be compatible with current gem5Geoffrey Blake
Brings the CheckerCPU back to life to allow FS and SE checking of the O3CPU. These changes have only been tested with the ARM ISA. Other ISAs potentially require modification.
2011-11-18SE/FS: Get rid of includes of config/full_system.hh.Gabe Black
2011-09-13LSQ: Only trigger a memory violation with a load/load if the value changes.Ali Saidi
Only create a memory ordering violation when the value could have changed between two subsequent loads, instead of just when loads go out-of-order to the same address. While not very common in the case of Alpha, with an architecture with a hardware table walker this can happen reasonably frequently beacuse a translation will miss and start a table walk and before the CPU re-schedules the faulting instruction another one will pass it to the same address (or cache block depending on the dendency checking). This patch has been tested with a couple of self-checking hand crafted programs to stress ordering between two cores. The performance improvement on SPEC benchmarks can be substantial (2-10%).
2011-09-09StaticInst: Merge StaticInst and StaticInstBase.Gabe Black
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.
2011-08-14O3: Add a pointer to the macroop for a microop in the dyninst.Gabe Black
2011-08-07Translation: Use a pointer type as the template argument.Gabe Black
This allows regular pointers and reference counted pointers without having to use any shim structures or other tricks.
2011-08-02O3: Get rid of the raw ExtMachInst constructor on DynInsts.Gabe Black
This constructor assumes that the ExtMachInst can be decoded directly into a StaticInst that's useful to execute. With the advent of microcoded instructions that's no longer true.
2011-07-02ExecContext: Rename the readBytes/writeBytes functions to readMem and writeMem.Gabe Black
readBytes and writeBytes had the word "bytes" in their names because they accessed blobs of bytes. This distinguished them from the read and write functions which handled higher level data types. Because those functions don't exist any more, this change renames readBytes and writeBytes to more general names, readMem and writeMem, which reflect the fact that they are how you read and write memory. This also makes their names more consistent with the register reading/writing functions, although those are still read and set for some reason.
2011-07-02ExecContext: Get rid of the now unused read/write templated functions.Gabe Black
2011-04-04CPU: Remove references to memory copy operationsAli Saidi
2011-04-04O3: Tighten memory order violation checking to 16 bytes.Ali Saidi
The comment in the code suggests that the checking granularity should be 16 bytes, however in reality the shift by 8 is 256 bytes which seems much larger than required.
2011-02-11O3: Enhance data address translation by supporting hardware page table walkers.Giacomo Gabrielli
Some ISAs (like ARM) relies on hardware page table walkers. For those ISAs, when a TLB miss occurs, initiateTranslation() can return with NoFault but with the translation unfinished. Instructions experiencing a delayed translation due to a hardware page table walk are deferred until the translation completes and kept into the IQ. In order to keep track of them, the IQ has been augmented with a queue of the outstanding delayed memory instructions. When their translation completes, instructions are re-executed (only their initiateAccess() was already executed; their DTB translation is now skipped). The IEW stage has been modified to support such a 2-pass execution.
2010-12-07O3: Support squashing all state after special instructionAli Saidi
For SPARC ASIs are added to the ExtMachInst. If the ASI is changed simply marking the instruction as Serializing isn't enough beacuse that only stops rename. This provides a mechanism to squash all the instructions and refetch them
2010-12-07O3: Make all instructions that write a misc. register not perform the write ↵Giacomo Gabrielli
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).
2010-11-08ARM/Alpha/Cpu: Change prefetchs to be more like normal loads.Ali Saidi
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.
2010-10-31ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors.Gabe Black
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.
2010-09-13Faults: Pass the StaticInst involved, if any, to a Fault's invoke method.Gabe Black
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.
2010-08-23CPU: Make Exec trace to print predication result (if false) for memory ↵Min Kyu Jeong
instructions
2010-08-23ARM/O3: store the result of the predicate evaluation in DynInst or Threadstate.Min Kyu Jeong
THis allows the CPU to handle predicated-false instructions accordingly. This particular patch makes loads that are predicated-false to be sent straight to the commit stage directly, not waiting for return of the data that was never requested since it was predicated-false.
2010-08-23CPU: Set a default value when readBytes faults.Ali Saidi
This was being done in read(), but if readBytes was called directly it wouldn't happen. Also, instead of setting the memory blob being read to -1 which would (I believe) require using memset with -1 as a parameter, this now uses bzero. It's hoped that it's more specialized behavior will make it slightly faster.
2010-08-13CPU: Add readBytes and writeBytes functions to the exec contexts.Gabe Black
2010-02-20BaseDynInst: Preserve the faults returned from read and write.Timothy M. Jones
When implementing timing address translations instead of atomic, I forgot to preserve the faults that are returned from the read and write calls. This patch reinstates them.
2010-02-12O3PCU: Split loads and stores that cross cache line boundaries.Timothy M. Jones
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.
2010-02-12BaseDynInst: Make the TLB translation timing instead of atomic.Timothy M. Jones
This initiates a timing translation and passes the read or write on to the processor before waiting for it to finish. Once the translation is finished, the instruction's state is updated via the 'finish' function. A new DataTranslation class is created to handle this. The idea is taken from the implementation of timing translations in TimingSimpleCPU by Gabe Black. This patch also separates out the timing translations from this CPU and uses the new DataTranslation class.
2009-09-23arch: nuke arch/isa_specific.hh and move stuff to generated config/the_isa.hhNathan Binkert
2009-08-01Fix setting of INST_FETCH flag for O3 CPU.Steve Reinhardt
It's still broken in inorder. Also enhance DPRINTFs in cache and physical memory so we can see more easily whether it's getting set or not.
2009-05-26types: add a type for thread IDs and try to use it everywhereNathan Binkert
2009-04-08tlb: More fixing of unified TLBNathan Binkert
2009-02-25ISA: Replace the translate functions in the TLBs with translateAtomic.Gabe Black
2009-02-25CPU: Get rid of translate... functions from various interface classes.Gabe Black
2008-11-10O3CPU: Make the instcount debugging stuff per-cpu.Clint Smullen
This is to prevent the assertion from firing if you have a large multicore. Also make sure that it's not compiled in when NDEBUG is defined
2008-11-02Add in Context IDs to the simulator. From now on, cpuId is almost never used,Lisa Hsu
the primary identifier for a hardware context should be contextId(). The concept of threads within a CPU remains, in the form of threadId() because sometimes you need to know which context within a cpu to manipulate.
2008-11-02make BaseCPU the provider of _cpuId, and cpuId() instead of being scatteredLisa Hsu
across the subclasses. generally make it so that member data is _cpuId and accessor functions are cpuId(). The ID val comes from the python (default -1 if none provided), and if it is -1, the index of cpuList will be given. this has passed util/regress quick and se.py -n4 and fs.py -n4 as well as standard switch.
2008-09-10style: Remove non-leading tabs everywhere they shouldn't be. Developers ↵Ali Saidi
should configure their editors to not insert tabs
2008-02-26TLB: Make a TLB base class and put a virtual demapPage function in it.Gabe Black
--HG-- extra : convert_revision : cc0e62a5a337fd5bf332ad33bed61c0d505a936f
2007-10-22CPU: Add functions to the "ExecContext"s that translate a given address.Gabe Black
--HG-- extra : convert_revision : 7d898c6b6b13094fd05326eaa0b095a3ab132397
2007-08-26O3 CPU: Remove alignment check from dynamic instruction read/write functions.Gabe Black
--HG-- extra : convert_revision : e5d415b4bf79353ef3c9f4dc5af09ab4102c55fb
2007-07-31Add a flag to indicate an instruction triggers a syscall in SE mode.Gabe Black
--HG-- extra : convert_revision : 1d0b3afdd8254f5b2fb4bbff1fa4a0536f78bb06
2007-06-20Fix compiler errors.Gabe Black
--HG-- extra : convert_revision : 2b10076a24cb36cb748e299011ae691f09c158cd
2007-04-14Add support for microcode and pull out the special branch delay slot ↵Gabe Black
handling. Branch delay slots need to be squash on a mispredict as well because the nnpc they saw was incorrect. --HG-- extra : convert_revision : 8b9c603616bcad254417a7a3fa3edfb4c8728719