Searched hist:2010 (Results 476 - 500 of 929) sorted by relevance
/gem5/src/sim/ | ||
H A D | arguments.hh | diff 7707:e5b6f1157be3 Sat Oct 16 02:57:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7693:f1db1000d957 Fri Oct 01 17:02:00 EDT 2010 Ali Saidi <Ali.Saidi@ARM.com> 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. |
H A D | stat_control.cc | diff 7768:cdb18c1b51ea Fri Nov 19 19:00:00 EST 2010 Ali Saidi <Ali.Saidi@ARM.com> SCons: Support building without an ISA diff 7068:08c34d3fb19d Sun Apr 18 16:23:00 EDT 2010 Nathan Binkert <nate@binkert.org> stats: make simTicks and simFreq accessible from stats.hh diff 7064:586b0e3a12b3 Thu Apr 15 19:24:00 EDT 2010 Nathan Binkert <nate@binkert.org> tick: rename Clock namespace to SimClock |
H A D | insttracer.hh | diff 7720:65d338a8dba4 Sun Oct 31 03:07:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7637:ee8afda92b31 Wed Aug 25 20:10:00 EDT 2010 Ali Saidi <Ali.Saidi@ARM.com> Tracing: Fix trace so 'Predicated False' doesn't show up diff 7600:eff7f79f7dfd Mon Aug 23 12:18:00 EDT 2010 Min Kyu Jeong <minkyu.jeong@arm.com> CPU: Make Exec trace to print predication result (if false) for memory instructions |
/gem5/src/mem/ruby/system/ | ||
H A D | DMASequencer.cc | diff 7544:90c5eb6a5e66 Fri Aug 20 14:46:00 EDT 2010 Brad Beckmann <Brad.Beckmann@amd.com> memtest: Memtester support for DMA This patch adds DMA testing to the Memtester and is inherits many changes from Polina's old tester_dma_extension patch. Since Ruby does not work in atomic mode, the atomic mode options are removed. diff 7453:1a5db3dd0f62 Fri Jun 11 02:17:00 EDT 2010 Nathan Binkert <nate@binkert.org> ruby: get rid of RefCnt and Allocator stuff use base/refcnt.hh This was somewhat tricky because the RefCnt API was somewhat odd. The biggest confusion was that the the RefCnt object's constructor that took a TYPE& cloned the object. I created an explicit virtual clone() function for things that took advantage of this version of the constructor. I was conservative and used clone() when I was in doubt of whether or not it was necessary. I still think that there are probably too many instances of clone(), but hopefully not too many. I converted several instances of const MsgPtr & to a simple MsgPtr. If the function wants to avoid the overhead of creating another reference, then it should just use a regular pointer instead of a ref counting ptr. There were a couple of instances where refcounted objects were created on the stack. This seems pretty dangerous since if you ever accidentally make a reference to that object with a ref counting pointer, bad things are bound to happen. diff 7055:4e24742201d7 Fri Apr 02 14:20:00 EDT 2010 Nathan Binkert <nate@binkert.org> ruby: get "using namespace" out of headers In addition to obvious changes, this required a slight change to the slicc grammar to allow types with :: in them. Otherwise slicc barfs on std::string which we need for the headers that slicc generates. diff 7039:bc0b6ea676b5 Mon Mar 22 21:43:00 EDT 2010 Nathan Binkert <nate@binkert.org> ruby: style pass diff 7008:90c097fb76e1 Sun Mar 14 23:58:00 EDT 2010 Nathan Binkert <nate@binkert.org> ruby: Fix copyrights on files Mostly files missed during import or screwed up during import diff 6922:1620cffaa3b6 Fri Jan 29 23:29:00 EST 2010 Brad Beckmann <Brad.Beckmann@amd.com> ruby: Removed static members in RubyPort including hitcallback Removed static members in RubyPort and removed the ruby request unique id. diff 6888:de8e755aca4f Fri Jan 29 23:29:00 EST 2010 Brad Beckmann <Brad.Beckmann@amd.com> ruby: Converted MOESI_hammer dma cntrl to new config system diff 6876:a658c315512c Fri Jan 29 23:29:00 EST 2010 Steve Reinhardt <steve.reinhardt@amd.com> ruby: Convert most Ruby objects to M5 SimObjects. The necessary companion conversion of Ruby objects generated by SLICC are converted to M5 SimObjects in the following patch, so this patch alone does not compile. Conversion of Garnet network models is also handled in a separate patch; that code is temporarily disabled from compiling to allow testing of interim code. |
H A D | Sequencer.py | diff 7019:a49fd5febdce Mon Mar 22 00:22:00 EDT 2010 Brad Beckmann <Brad.Beckmann@amd.com> ruby: Added copyright to many Ruby *.py files diff 6899:f8057af86bf7 Fri Jan 29 23:29:00 EST 2010 Brad Beckmann <Brad.Beckmann@amd.com> ruby: added the GEMS ruby tester diff 6893:9cdf9b65d946 Fri Jan 29 23:29:00 EST 2010 Brad Beckmann <Brad.Beckmann@amd.com> ruby: FS support using the new configuration system diff 6882:898047a3672c Fri Jan 29 23:29:00 EST 2010 Brad Beckmann <Brad.Beckmann@amd.com> ruby: Ruby changes required to use the python config system This patch includes the necessary changes to connect ruby objects using the python configuration system. Mainly it consists of removing unnecessary ruby object pointers and connecting the necessary object pointers using the generated param objects. This patch includes the slicc changes necessary to connect generated ruby objects together using the python configuraiton system. 6876:a658c315512c Fri Jan 29 23:29:00 EST 2010 Steve Reinhardt <steve.reinhardt@amd.com> ruby: Convert most Ruby objects to M5 SimObjects. The necessary companion conversion of Ruby objects generated by SLICC are converted to M5 SimObjects in the following patch, so this patch alone does not compile. Conversion of Garnet network models is also handled in a separate patch; that code is temporarily disabled from compiling to allow testing of interim code. |
/gem5/src/arch/x86/isa/insts/general_purpose/data_transfer/ | ||
H A D | move.py | diff 7622:b49144029ec8 Mon Aug 23 12:44:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> X86: Mark serializing macroops and regular instructions as such. diff 7087:fb8d5786ff30 Mon May 24 01:44:00 EDT 2010 Nathan Binkert <nate@binkert.org> copyright: Change HP copyright on x86 code to be more friendly |
/gem5/src/arch/x86/isa/microops/ | ||
H A D | seqop.isa | diff 7789:f455790bcd47 Wed Dec 08 03:27:00 EST 2010 Gabe Black <gblack@eecs.umich.edu> X86: Take advantage of new PCState syntax. diff 7720:65d338a8dba4 Sun Oct 31 03:07:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7626:bdd926760470 Mon Aug 23 12:44:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> X86: Get rid of the flagless microop constructor. This will reduce clutter in the source and hopefully speed up compilation. diff 7620:3d8a23caa1ef Mon Aug 23 12:44:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> X86: Consolidate extra microop flags into one parameter. This single parameter replaces the collection of bools that set up various flavors of microops. A flag parameter also allows other flags to be set like the serialize before/after flags, etc., without having to change the constructor. diff 7087:fb8d5786ff30 Mon May 24 01:44:00 EDT 2010 Nathan Binkert <nate@binkert.org> copyright: Change HP copyright on x86 code to be more friendly |
H A D | limmop.isa | diff 7626:bdd926760470 Mon Aug 23 12:44:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> X86: Get rid of the flagless microop constructor. This will reduce clutter in the source and hopefully speed up compilation. diff 7620:3d8a23caa1ef Mon Aug 23 12:44:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> X86: Consolidate extra microop flags into one parameter. This single parameter replaces the collection of bools that set up various flavors of microops. A flag parameter also allows other flags to be set like the serialize before/after flags, etc., without having to change the constructor. diff 7087:fb8d5786ff30 Mon May 24 01:44:00 EDT 2010 Nathan Binkert <nate@binkert.org> copyright: Change HP copyright on x86 code to be more friendly |
/gem5/src/arch/x86/ | ||
H A D | faults.cc | diff 7720:65d338a8dba4 Sun Oct 31 03:07:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7681:61e31534522d Tue Sep 14 03:27:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> X86: Make unrecognized instructions behave better in x86. diff 7678:f19b6a3a8cec Mon Sep 13 22:26:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7625:b1e69203bae9 Mon Aug 23 12:44:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> X86: Make the TLB fault instead of panic when something is unmapped in SE mode. The fault object, if invoked, would then panic. This is a bit less direct, but it means speculative execution won't panic the simulator. diff 7087:fb8d5786ff30 Mon May 24 01:44:00 EDT 2010 Nathan Binkert <nate@binkert.org> copyright: Change HP copyright on x86 code to be more friendly |
H A D | utility.hh | diff 7720:65d338a8dba4 Sun Oct 31 03:07:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7707:e5b6f1157be3 Sat Oct 16 02:57:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7693:f1db1000d957 Fri Oct 01 17:02:00 EDT 2010 Ali Saidi <Ali.Saidi@ARM.com> 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. diff 7680:f4eda002333b Tue Sep 14 03:29:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> CPU: Trim unnecessary includes from some common files. This reduces the scope of those includes and makes it less likely for there to be a dependency loop. This also moves the hashing functions associated with ExtMachInst objects to be with the ExtMachInst definitions and out of utility.hh. diff 7629:0f0c231e3e97 Mon Aug 23 19:14:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> X86: Create a directory for files that define register indexes. This is to help tidy up arch/x86. These files should not be used external to the ISA. diff 7627:3b0c4b819651 Mon Aug 23 19:14:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> ISA: Get rid of old, unused utility functions cluttering up the ISAs. diff 7087:fb8d5786ff30 Mon May 24 01:44:00 EDT 2010 Nathan Binkert <nate@binkert.org> copyright: Change HP copyright on x86 code to be more friendly |
H A D | nativetrace.cc | diff 7720:65d338a8dba4 Sun Oct 31 03:07:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7678:f19b6a3a8cec Mon Sep 13 22:26:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7629:0f0c231e3e97 Mon Aug 23 19:14:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> X86: Create a directory for files that define register indexes. This is to help tidy up arch/x86. These files should not be used external to the ISA. |
H A D | registers.hh | diff 7649:a6a6177a5ffa Wed Aug 25 20:10:00 EDT 2010 Min Kyu Jeong <minkyu.jeong@arm.com> 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 diff 7629:0f0c231e3e97 Mon Aug 23 19:14:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> X86: Create a directory for files that define register indexes. This is to help tidy up arch/x86. These files should not be used external to the ISA. diff 7087:fb8d5786ff30 Mon May 24 01:44:00 EDT 2010 Nathan Binkert <nate@binkert.org> copyright: Change HP copyright on x86 code to be more friendly |
/gem5/src/arch/sparc/ | ||
H A D | utility.cc | diff 7741:340b6f01d69b Thu Nov 11 05:03:00 EST 2010 Gabe Black <gblack@eecs.umich.edu> SPARC: Clean up some historical style issues. diff 7720:65d338a8dba4 Sun Oct 31 03:07:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7707:e5b6f1157be3 Sat Oct 16 02:57:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7693:f1db1000d957 Fri Oct 01 17:02:00 EDT 2010 Ali Saidi <Ali.Saidi@ARM.com> 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. diff 7678:f19b6a3a8cec Mon Sep 13 22:26:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. |
H A D | utility.hh | diff 7741:340b6f01d69b Thu Nov 11 05:03:00 EST 2010 Gabe Black <gblack@eecs.umich.edu> SPARC: Clean up some historical style issues. diff 7720:65d338a8dba4 Sun Oct 31 03:07:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7707:e5b6f1157be3 Sat Oct 16 02:57:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7693:f1db1000d957 Fri Oct 01 17:02:00 EDT 2010 Ali Saidi <Ali.Saidi@ARM.com> 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. diff 7678:f19b6a3a8cec Mon Sep 13 22:26:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7627:3b0c4b819651 Mon Aug 23 19:14:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> ISA: Get rid of old, unused utility functions cluttering up the ISAs. diff 7572:3d72ff41f9d2 Sun Aug 22 21:39:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> SPARC: Fix some style issues in utility.hh. |
/gem5/src/arch/arm/ | ||
H A D | isa.cc | diff 7783:9b880b40ac10 Tue Dec 07 19:19:00 EST 2010 Giacomo Gabrielli <Giacomo.Gabrielli@arm.com> 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). diff 7757:d7360f5052b2 Mon Nov 15 15:04:00 EST 2010 Ali Saidi <Ali.Saidi@ARM.com> ARM: Return an FailUnimp instruction when an unimplemented CP15 register is accessed. Just panicing in readMiscReg() doesn't work because a speculative access in the o3 model can end the simulation. diff 7749:859e8bc1cdc2 Mon Nov 15 15:04:00 EST 2010 Ali Saidi <Ali.Saidi@ARM.com> ARM: Cache the misc regs at the TLB to limit readMiscReg() calls. diff 7731:e1eace3a118a Mon Nov 08 14:58:00 EST 2010 Ali Saidi <Ali.Saidi@ARM.com> ARM: Keep the warnings to a minimum. These warnings still need to be addresses, but pages of them is counterproductive. diff 7720:65d338a8dba4 Sun Oct 31 03:07:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7692:8173327c9c65 Fri Oct 01 17:02:00 EDT 2010 Ali Saidi <Ali.Saidi@ARM.com> ARM: Clean up use of TBit and JBit. Rather tha constantly using ULL(1) << PcXBitShift define those directly. Additionally, add some helper functions to further clean up the code. diff 7678:f19b6a3a8cec Mon Sep 13 22:26:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7645:873b90fa0eca Wed Aug 25 20:10:00 EDT 2010 Ali Saidi <ali.saidi@arm.com> ARM: Set the high bits in the part number so it's considered new by some code. diff 7644:62873d5c2bfc Wed Aug 25 20:10:00 EDT 2010 Ali Saidi <ali.saidi@arm.com> ARM: Fix VFP enabled checks for mem instructions diff 7640:5286a8a469c5 Wed Aug 25 20:10:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> ARM: Implement CPACR register and return Undefined Instruction when FP access is disabled. |
/gem5/src/dev/arm/ | ||
H A D | SConscript | diff 7754:8ae6f4055594 Mon Nov 15 15:04:00 EST 2010 William Wang <William.Wang@arm.com> ARM: Add a Keyboard Mouse Interface controller diff 7753:d3e613312953 Mon Nov 15 15:04:00 EST 2010 William Wang <William.Wang@arm.com> ARM: Implement a CLCD Frame buffer diff 7695:d9efdb9ac88e Fri Oct 01 17:04:00 EDT 2010 Prakash Ramrakhyani <Prakash.Ramrakhyani@arm.com> ARM: Fix some subtle bugs in the GIC The GIC code can write to the registers with 8, 16, or 32 byte accesses which could set/clear different numbers of interrupts. diff 7584:28ddf6d9e982 Mon Aug 23 12:18:00 EDT 2010 Ali Saidi <Ali.Saidi@arm.com> ARM: Add I/O devices for booting linux diff 7090:5f64c5048fbd Wed Jun 02 01:57:00 EDT 2010 Ali Saidi <Ali.Saidi@ARM.com> ARM: Adjust some copyrights |
H A D | pl011.cc | diff 7733:08d6a773d1b6 Mon Nov 08 14:58:00 EST 2010 Ali Saidi <Ali.Saidi@ARM.com> ARM: Add checkpointing support diff 7587:177151a54462 Mon Aug 23 12:18:00 EDT 2010 Ali Saidi <Ali.Saidi@arm.com> ARM: Change how the AMBA device ID checking is done to make it more generic 7584:28ddf6d9e982 Mon Aug 23 12:18:00 EDT 2010 Ali Saidi <Ali.Saidi@arm.com> ARM: Add I/O devices for booting linux |
/gem5/src/mem/ruby/slicc_interface/ | ||
H A D | AbstractController.hh | diff 7055:4e24742201d7 Fri Apr 02 14:20:00 EDT 2010 Nathan Binkert <nate@binkert.org> ruby: get "using namespace" out of headers In addition to obvious changes, this required a slight change to the slicc grammar to allow types with :: in them. Otherwise slicc barfs on std::string which we need for the headers that slicc generates. diff 7039:bc0b6ea676b5 Mon Mar 22 21:43:00 EDT 2010 Nathan Binkert <nate@binkert.org> ruby: style pass diff 7008:90c097fb76e1 Sun Mar 14 23:58:00 EDT 2010 Nathan Binkert <nate@binkert.org> ruby: Fix copyrights on files Mostly files missed during import or screwed up during import diff 6881:5a61a8a9009a Fri Jan 29 23:29:00 EST 2010 Brad Beckmann <Brad.Beckmann@amd.com> ruby: connects sm queues to the network diff 6877:2a1a3d916ca8 Fri Jan 29 23:29:00 EST 2010 Steve Reinhardt <steve.reinhardt@amd.com> ruby: Make SLICC-generated objects SimObjects. Also add SLICC support for state-machine parameter defaults (passed through to Python as SimObject Param defaults). diff 6876:a658c315512c Fri Jan 29 23:29:00 EST 2010 Steve Reinhardt <steve.reinhardt@amd.com> ruby: Convert most Ruby objects to M5 SimObjects. The necessary companion conversion of Ruby objects generated by SLICC are converted to M5 SimObjects in the following patch, so this patch alone does not compile. Conversion of Garnet network models is also handled in a separate patch; that code is temporarily disabled from compiling to allow testing of interim code. diff 6863:21fbf0412e0d Tue Jan 19 18:11:00 EST 2010 Derek Hower <drh5@cs.wisc.edu> ruby: new atomics implementation This patch changes the way that Ruby handles atomic RMW instructions. This implementation, unlike the prior one, is protocol independent. It works by locking an address from the sequencer immediately after the read portion of an RMW completes. When that address is locked, the coherence controller will only satisfy requests coming from one port (e.g., the mandatory queue) and will ignore all others. After the write portion completed, the line is unlocked. This should also work with multi-line atomics, as long as the blocks are always acquired in the same order. |
/gem5/src/arch/x86/isa/formats/ | ||
H A D | unknown.isa | diff 7720:65d338a8dba4 Sun Oct 31 03:07:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> 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. diff 7681:61e31534522d Tue Sep 14 03:27:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> X86: Make unrecognized instructions behave better in x86. diff 7087:fb8d5786ff30 Mon May 24 01:44:00 EDT 2010 Nathan Binkert <nate@binkert.org> copyright: Change HP copyright on x86 code to be more friendly |
/gem5/src/arch/power/ | ||
H A D | tlb.cc | diff 7676:92274350b953 Fri Sep 10 17:58:00 EDT 2010 Nathan Binkert <nate@binkert.org> style: fix sorting of includes and whitespace in some files diff 7461:5a07045d0af2 Tue Jun 15 04:18:00 EDT 2010 Nathan Binkert <nate@binkert.org> stats: only consider a formula initialized if there is a formula diff 6972:b6482c4c89e3 Fri Feb 12 14:53:00 EST 2010 Timothy M. Jones <tjones1@inf.ed.ac.uk> Power ISA: Add an alignment fault to Power ISA and check alignment in TLB. |
/gem5/src/dev/alpha/ | ||
H A D | tsunami_io.cc | diff 7683:f81f5f27592b Thu Sep 16 23:24:00 EDT 2010 Steve Reinhardt <steve.reinhardt@amd.com> devices: undo cset 017baf09599f that added timer drain functions. It's not the right fix for the checkpoint deadlock problem Brad was having, and creates another bug where the system can deadlock on restore. Brad can't reproduce the original bug right now, so we'll wait until it arises again and then try to fix it the right way then. diff 7559:017baf09599f Fri Aug 20 14:46:00 EDT 2010 Brad Beckmann <Brad.Beckmann@amd.com> devices: Fixed periodic interrupts to work with draining Added drain functions to the RTC and 8254 timer so that periodic interrupts stop when the system is draining. This patch is needed to checkpoint in timing mode. Otherwise under certain situations, the event queue will never be completely empty. diff 7064:586b0e3a12b3 Thu Apr 15 19:24:00 EDT 2010 Nathan Binkert <nate@binkert.org> tick: rename Clock namespace to SimClock |
/gem5/src/arch/arm/isa/templates/ | ||
H A D | neon.isa | diff 7644:62873d5c2bfc Wed Aug 25 20:10:00 EDT 2010 Ali Saidi <ali.saidi@arm.com> ARM: Fix VFP enabled checks for mem instructions diff 7641:788c719d0fc8 Wed Aug 25 20:10:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> ARM: Fix type comparison warnings in Neon. 7639:8c09b7ff5b57 Wed Aug 25 20:10:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> ARM: Implement all ARM SIMD instructions. |
/gem5/tests/ | ||
H A D | run.py | diff 7525:722f2ad014a7 Tue Aug 17 08:06:00 EDT 2010 Steve Reinhardt <steve.reinhardt@amd.com> sim: make Python Root object a singleton Enforce that the Python Root SimObject is instantiated only once. The C++ Root object already panics if more than one is created. This change avoids the need to track what the root object is, since it's available from Root.getInstance() (if it exists). It's now redundant to have the user pass the root object to functions like instantiate(), checkpoint(), and restoreCheckpoint(), so that arg is gone. Users who use configs/common/Simulate.py should not notice. diff 6928:5bd33f7c26ea Fri Jan 29 23:29:00 EST 2010 Brad Beckmann <Brad.Beckmann@amd.com> m5: Regression Tester Update This patch includes the necessary regression updates to test the new ruby configuration system. The patch includes support for multiple ruby protocols and adds the ruby random tester. The patch removes atomic mode test for ruby since ruby does not support atomic mode acceses. These tests can be added back in when ruby supports atomic mode for real. diff 6874:22df98a968bf Fri Jan 29 23:29:00 EST 2010 Steve Reinhardt <Steve.Reinhardt@amd.com> tests: added M5_TEST_PROGS environment variable to allow override of global location for regression test binaries. |
/gem5/util/ | ||
H A D | regress | diff 7735:a1a85250e897 Mon Nov 08 14:58:00 EST 2010 Ali Saidi <Ali.Saidi@ARM.com> ARM: Add full-system regressions diff 7047:04d988a19ae9 Tue Mar 23 19:31:00 EDT 2010 Nathan Binkert <nate@binkert.org> regress: add some new options add -n/--no-exec which doesn't execute scons, but just prints the command line add -j0 which tries to calculate how many cpus you have add -D/--build-dir to specify a build directory other than ./build diff 6928:5bd33f7c26ea Fri Jan 29 23:29:00 EST 2010 Brad Beckmann <Brad.Beckmann@amd.com> m5: Regression Tester Update This patch includes the necessary regression updates to test the new ruby configuration system. The patch includes support for multiple ruby protocols and adds the ruby random tester. The patch removes atomic mode test for ruby since ruby does not support atomic mode acceses. These tests can be added back in when ruby supports atomic mode for real. |
/gem5/src/arch/x86/isa/ | ||
H A D | macroop.isa | diff 7621:3a6468fa514f Mon Aug 23 12:44:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> X86: Add a .serializing directive that makes a macroop serializing. This directive really just tells the macroop to set IsSerializing and IsSerializeAfter on its final microop. diff 7620:3d8a23caa1ef Mon Aug 23 12:44:00 EDT 2010 Gabe Black <gblack@eecs.umich.edu> X86: Consolidate extra microop flags into one parameter. This single parameter replaces the collection of bools that set up various flavors of microops. A flag parameter also allows other flags to be set like the serialize before/after flags, etc., without having to change the constructor. diff 7087:fb8d5786ff30 Mon May 24 01:44:00 EDT 2010 Nathan Binkert <nate@binkert.org> copyright: Change HP copyright on x86 code to be more friendly |
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