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Decode: Pull instruction decoding out of the StaticInst class into its own. This change pulls the instruction decoding machinery (including caches) out of the StaticInst class and puts it into its own class. This has a few intrinsic benefits. First, the StaticInst code, which has gotten to be quite large, gets simpler. Second, the code that handles decode caching is now separated out into its own component and can be looked at in isolation, making it easier to understand. I took the opportunity to restructure the code a bit which will hopefully also help. Beyond that, this change also lays some ground work for each ISA to have its own, potentially stateful decode object. We'd be able to include less contextualizing information in the ExtMachInst objects since that context would be applied at the decoder. Also, the decoder could "know" ahead of time that all the instructions it's going to see are going to be, for instance, 64 bit mode, and it will have one less thing to check when it decodes them. Because the decode caching mechanism has been separated out, it's now possible to have multiple caches which correspond to different types of decoding context. Having one cache for each element of the cross product of different configurations may become prohibitive, so it may be desirable to clear out the cache when relatively static state changes and not to have one for each setting. Because the decode function is no longer universally accessible as a static member of the StaticInst class, a new function was added to the ThreadContexts that returns the applicable decode object.
2011-09-09 11:30:01 +02:00
/*
* Copyright (c) 2011 Google
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Authors: Gabe Black
*/
#ifndef __CPU_DECODE_CACHE_HH__
#define __CPU_DECODE_CACHE_HH__
#include "arch/isa_traits.hh"
#include "arch/types.hh"
#include "base/hashmap.hh"
#include "config/the_isa.hh"
ISA,CPU: Generalize and split out the components of the decode cache. This will allow it to be specialized by the ISAs. The existing caching scheme is provided by the BasicDecodeCache in the GenericISA namespace and is built from the generalized components. --HG-- rename : src/cpu/decode_cache.cc => src/arch/generic/decode_cache.cc
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#include "cpu/static_inst_fwd.hh"
Decode: Pull instruction decoding out of the StaticInst class into its own. This change pulls the instruction decoding machinery (including caches) out of the StaticInst class and puts it into its own class. This has a few intrinsic benefits. First, the StaticInst code, which has gotten to be quite large, gets simpler. Second, the code that handles decode caching is now separated out into its own component and can be looked at in isolation, making it easier to understand. I took the opportunity to restructure the code a bit which will hopefully also help. Beyond that, this change also lays some ground work for each ISA to have its own, potentially stateful decode object. We'd be able to include less contextualizing information in the ExtMachInst objects since that context would be applied at the decoder. Also, the decoder could "know" ahead of time that all the instructions it's going to see are going to be, for instance, 64 bit mode, and it will have one less thing to check when it decodes them. Because the decode caching mechanism has been separated out, it's now possible to have multiple caches which correspond to different types of decoding context. Having one cache for each element of the cross product of different configurations may become prohibitive, so it may be desirable to clear out the cache when relatively static state changes and not to have one for each setting. Because the decode function is no longer universally accessible as a static member of the StaticInst class, a new function was added to the ThreadContexts that returns the applicable decode object.
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ISA: Make the decode function part of the ISA's decoder.
2012-05-25 09:55:24 +02:00
namespace TheISA
{
class Decoder;
}
Decode: Pull instruction decoding out of the StaticInst class into its own. This change pulls the instruction decoding machinery (including caches) out of the StaticInst class and puts it into its own class. This has a few intrinsic benefits. First, the StaticInst code, which has gotten to be quite large, gets simpler. Second, the code that handles decode caching is now separated out into its own component and can be looked at in isolation, making it easier to understand. I took the opportunity to restructure the code a bit which will hopefully also help. Beyond that, this change also lays some ground work for each ISA to have its own, potentially stateful decode object. We'd be able to include less contextualizing information in the ExtMachInst objects since that context would be applied at the decoder. Also, the decoder could "know" ahead of time that all the instructions it's going to see are going to be, for instance, 64 bit mode, and it will have one less thing to check when it decodes them. Because the decode caching mechanism has been separated out, it's now possible to have multiple caches which correspond to different types of decoding context. Having one cache for each element of the cross product of different configurations may become prohibitive, so it may be desirable to clear out the cache when relatively static state changes and not to have one for each setting. Because the decode function is no longer universally accessible as a static member of the StaticInst class, a new function was added to the ThreadContexts that returns the applicable decode object.
2011-09-09 11:30:01 +02:00
ISA,CPU: Generalize and split out the components of the decode cache. This will allow it to be specialized by the ISAs. The existing caching scheme is provided by the BasicDecodeCache in the GenericISA namespace and is built from the generalized components. --HG-- rename : src/cpu/decode_cache.cc => src/arch/generic/decode_cache.cc
2012-05-26 22:45:12 +02:00
namespace DecodeCache
Decode: Pull instruction decoding out of the StaticInst class into its own. This change pulls the instruction decoding machinery (including caches) out of the StaticInst class and puts it into its own class. This has a few intrinsic benefits. First, the StaticInst code, which has gotten to be quite large, gets simpler. Second, the code that handles decode caching is now separated out into its own component and can be looked at in isolation, making it easier to understand. I took the opportunity to restructure the code a bit which will hopefully also help. Beyond that, this change also lays some ground work for each ISA to have its own, potentially stateful decode object. We'd be able to include less contextualizing information in the ExtMachInst objects since that context would be applied at the decoder. Also, the decoder could "know" ahead of time that all the instructions it's going to see are going to be, for instance, 64 bit mode, and it will have one less thing to check when it decodes them. Because the decode caching mechanism has been separated out, it's now possible to have multiple caches which correspond to different types of decoding context. Having one cache for each element of the cross product of different configurations may become prohibitive, so it may be desirable to clear out the cache when relatively static state changes and not to have one for each setting. Because the decode function is no longer universally accessible as a static member of the StaticInst class, a new function was added to the ThreadContexts that returns the applicable decode object.
2011-09-09 11:30:01 +02:00
{
ISA,CPU: Generalize and split out the components of the decode cache. This will allow it to be specialized by the ISAs. The existing caching scheme is provided by the BasicDecodeCache in the GenericISA namespace and is built from the generalized components. --HG-- rename : src/cpu/decode_cache.cc => src/arch/generic/decode_cache.cc
2012-05-26 22:45:12 +02:00
/// Hash for decoded instructions.
typedef m5::hash_map<TheISA::ExtMachInst, StaticInstPtr> InstMap;
/// A sparse map from an Addr to a Value, stored in page chunks.
template<class Value>
class AddrMap
{
protected:
// A pages worth of cache entries.
struct CachePage {
Value items[TheISA::PageBytes];
Decode: Pull instruction decoding out of the StaticInst class into its own. This change pulls the instruction decoding machinery (including caches) out of the StaticInst class and puts it into its own class. This has a few intrinsic benefits. First, the StaticInst code, which has gotten to be quite large, gets simpler. Second, the code that handles decode caching is now separated out into its own component and can be looked at in isolation, making it easier to understand. I took the opportunity to restructure the code a bit which will hopefully also help. Beyond that, this change also lays some ground work for each ISA to have its own, potentially stateful decode object. We'd be able to include less contextualizing information in the ExtMachInst objects since that context would be applied at the decoder. Also, the decoder could "know" ahead of time that all the instructions it's going to see are going to be, for instance, 64 bit mode, and it will have one less thing to check when it decodes them. Because the decode caching mechanism has been separated out, it's now possible to have multiple caches which correspond to different types of decoding context. Having one cache for each element of the cross product of different configurations may become prohibitive, so it may be desirable to clear out the cache when relatively static state changes and not to have one for each setting. Because the decode function is no longer universally accessible as a static member of the StaticInst class, a new function was added to the ThreadContexts that returns the applicable decode object.
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};
ISA,CPU: Generalize and split out the components of the decode cache. This will allow it to be specialized by the ISAs. The existing caching scheme is provided by the BasicDecodeCache in the GenericISA namespace and is built from the generalized components. --HG-- rename : src/cpu/decode_cache.cc => src/arch/generic/decode_cache.cc
2012-05-26 22:45:12 +02:00
// A map of cache pages which allows a sparse mapping.
typedef typename m5::hash_map<Addr, CachePage *> PageMap;
typedef typename PageMap::iterator PageIt;
// Mini cache of recent lookups.
PageIt recent[2];
PageMap pageMap;
/// Update the mini cache of recent lookups.
/// @param recentest The most recent result;
void
update(PageIt recentest)
{
recent[1] = recent[0];
recent[0] = recentest;
}
Decode: Pull instruction decoding out of the StaticInst class into its own. This change pulls the instruction decoding machinery (including caches) out of the StaticInst class and puts it into its own class. This has a few intrinsic benefits. First, the StaticInst code, which has gotten to be quite large, gets simpler. Second, the code that handles decode caching is now separated out into its own component and can be looked at in isolation, making it easier to understand. I took the opportunity to restructure the code a bit which will hopefully also help. Beyond that, this change also lays some ground work for each ISA to have its own, potentially stateful decode object. We'd be able to include less contextualizing information in the ExtMachInst objects since that context would be applied at the decoder. Also, the decoder could "know" ahead of time that all the instructions it's going to see are going to be, for instance, 64 bit mode, and it will have one less thing to check when it decodes them. Because the decode caching mechanism has been separated out, it's now possible to have multiple caches which correspond to different types of decoding context. Having one cache for each element of the cross product of different configurations may become prohibitive, so it may be desirable to clear out the cache when relatively static state changes and not to have one for each setting. Because the decode function is no longer universally accessible as a static member of the StaticInst class, a new function was added to the ThreadContexts that returns the applicable decode object.
2011-09-09 11:30:01 +02:00
ISA,CPU: Generalize and split out the components of the decode cache. This will allow it to be specialized by the ISAs. The existing caching scheme is provided by the BasicDecodeCache in the GenericISA namespace and is built from the generalized components. --HG-- rename : src/cpu/decode_cache.cc => src/arch/generic/decode_cache.cc
2012-05-26 22:45:12 +02:00
/// Attempt to find the CacheePage which goes with a particular
/// address. First check the small cache of recent results, then
/// actually look in the hash_map.
/// @param addr The address to look up.
CachePage *
getPage(Addr addr)
Decode: Pull instruction decoding out of the StaticInst class into its own. This change pulls the instruction decoding machinery (including caches) out of the StaticInst class and puts it into its own class. This has a few intrinsic benefits. First, the StaticInst code, which has gotten to be quite large, gets simpler. Second, the code that handles decode caching is now separated out into its own component and can be looked at in isolation, making it easier to understand. I took the opportunity to restructure the code a bit which will hopefully also help. Beyond that, this change also lays some ground work for each ISA to have its own, potentially stateful decode object. We'd be able to include less contextualizing information in the ExtMachInst objects since that context would be applied at the decoder. Also, the decoder could "know" ahead of time that all the instructions it's going to see are going to be, for instance, 64 bit mode, and it will have one less thing to check when it decodes them. Because the decode caching mechanism has been separated out, it's now possible to have multiple caches which correspond to different types of decoding context. Having one cache for each element of the cross product of different configurations may become prohibitive, so it may be desirable to clear out the cache when relatively static state changes and not to have one for each setting. Because the decode function is no longer universally accessible as a static member of the StaticInst class, a new function was added to the ThreadContexts that returns the applicable decode object.
2011-09-09 11:30:01 +02:00
{
ISA,CPU: Generalize and split out the components of the decode cache. This will allow it to be specialized by the ISAs. The existing caching scheme is provided by the BasicDecodeCache in the GenericISA namespace and is built from the generalized components. --HG-- rename : src/cpu/decode_cache.cc => src/arch/generic/decode_cache.cc
2012-05-26 22:45:12 +02:00
Addr page_addr = addr & ~(TheISA::PageBytes - 1);
Decode: Pull instruction decoding out of the StaticInst class into its own. This change pulls the instruction decoding machinery (including caches) out of the StaticInst class and puts it into its own class. This has a few intrinsic benefits. First, the StaticInst code, which has gotten to be quite large, gets simpler. Second, the code that handles decode caching is now separated out into its own component and can be looked at in isolation, making it easier to understand. I took the opportunity to restructure the code a bit which will hopefully also help. Beyond that, this change also lays some ground work for each ISA to have its own, potentially stateful decode object. We'd be able to include less contextualizing information in the ExtMachInst objects since that context would be applied at the decoder. Also, the decoder could "know" ahead of time that all the instructions it's going to see are going to be, for instance, 64 bit mode, and it will have one less thing to check when it decodes them. Because the decode caching mechanism has been separated out, it's now possible to have multiple caches which correspond to different types of decoding context. Having one cache for each element of the cross product of different configurations may become prohibitive, so it may be desirable to clear out the cache when relatively static state changes and not to have one for each setting. Because the decode function is no longer universally accessible as a static member of the StaticInst class, a new function was added to the ThreadContexts that returns the applicable decode object.
2011-09-09 11:30:01 +02:00
ISA,CPU: Generalize and split out the components of the decode cache. This will allow it to be specialized by the ISAs. The existing caching scheme is provided by the BasicDecodeCache in the GenericISA namespace and is built from the generalized components. --HG-- rename : src/cpu/decode_cache.cc => src/arch/generic/decode_cache.cc
2012-05-26 22:45:12 +02:00
// Check against recent lookups.
if (recent[0] != pageMap.end()) {
if (recent[0]->first == page_addr)
return recent[0]->second;
if (recent[1] != pageMap.end() &&
recent[1]->first == page_addr) {
update(recent[1]);
// recent[1] has just become recent[0].
return recent[0]->second;
}
}
CPU: Simplify the implementation of the decode cache. Also reorganize it to make it more amenable to being rearranged later.
2012-05-25 09:54:39 +02:00
ISA,CPU: Generalize and split out the components of the decode cache. This will allow it to be specialized by the ISAs. The existing caching scheme is provided by the BasicDecodeCache in the GenericISA namespace and is built from the generalized components. --HG-- rename : src/cpu/decode_cache.cc => src/arch/generic/decode_cache.cc
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// Actually look in the has_map.
PageIt it = pageMap.find(page_addr);
if (it != pageMap.end()) {
update(it);
return it->second;
}
Decode: Pull instruction decoding out of the StaticInst class into its own. This change pulls the instruction decoding machinery (including caches) out of the StaticInst class and puts it into its own class. This has a few intrinsic benefits. First, the StaticInst code, which has gotten to be quite large, gets simpler. Second, the code that handles decode caching is now separated out into its own component and can be looked at in isolation, making it easier to understand. I took the opportunity to restructure the code a bit which will hopefully also help. Beyond that, this change also lays some ground work for each ISA to have its own, potentially stateful decode object. We'd be able to include less contextualizing information in the ExtMachInst objects since that context would be applied at the decoder. Also, the decoder could "know" ahead of time that all the instructions it's going to see are going to be, for instance, 64 bit mode, and it will have one less thing to check when it decodes them. Because the decode caching mechanism has been separated out, it's now possible to have multiple caches which correspond to different types of decoding context. Having one cache for each element of the cross product of different configurations may become prohibitive, so it may be desirable to clear out the cache when relatively static state changes and not to have one for each setting. Because the decode function is no longer universally accessible as a static member of the StaticInst class, a new function was added to the ThreadContexts that returns the applicable decode object.
2011-09-09 11:30:01 +02:00
ISA,CPU: Generalize and split out the components of the decode cache. This will allow it to be specialized by the ISAs. The existing caching scheme is provided by the BasicDecodeCache in the GenericISA namespace and is built from the generalized components. --HG-- rename : src/cpu/decode_cache.cc => src/arch/generic/decode_cache.cc
2012-05-26 22:45:12 +02:00
// Didn't find an existing page, so add a new one.
CachePage *newPage = new CachePage;
page_addr = page_addr & ~(TheISA::PageBytes - 1);
typename PageMap::value_type to_insert(page_addr, newPage);
update(pageMap.insert(to_insert).first);
return newPage;
}
Decode: Pull instruction decoding out of the StaticInst class into its own. This change pulls the instruction decoding machinery (including caches) out of the StaticInst class and puts it into its own class. This has a few intrinsic benefits. First, the StaticInst code, which has gotten to be quite large, gets simpler. Second, the code that handles decode caching is now separated out into its own component and can be looked at in isolation, making it easier to understand. I took the opportunity to restructure the code a bit which will hopefully also help. Beyond that, this change also lays some ground work for each ISA to have its own, potentially stateful decode object. We'd be able to include less contextualizing information in the ExtMachInst objects since that context would be applied at the decoder. Also, the decoder could "know" ahead of time that all the instructions it's going to see are going to be, for instance, 64 bit mode, and it will have one less thing to check when it decodes them. Because the decode caching mechanism has been separated out, it's now possible to have multiple caches which correspond to different types of decoding context. Having one cache for each element of the cross product of different configurations may become prohibitive, so it may be desirable to clear out the cache when relatively static state changes and not to have one for each setting. Because the decode function is no longer universally accessible as a static member of the StaticInst class, a new function was added to the ThreadContexts that returns the applicable decode object.
2011-09-09 11:30:01 +02:00
public:
ISA,CPU: Generalize and split out the components of the decode cache. This will allow it to be specialized by the ISAs. The existing caching scheme is provided by the BasicDecodeCache in the GenericISA namespace and is built from the generalized components. --HG-- rename : src/cpu/decode_cache.cc => src/arch/generic/decode_cache.cc
2012-05-26 22:45:12 +02:00
/// Constructor
AddrMap()
{
recent[0] = recent[1] = pageMap.end();
}
Value &
lookup(Addr addr)
{
CachePage *page = getPage(addr);
return page->items[addr & (TheISA::PageBytes - 1)];
}
Decode: Pull instruction decoding out of the StaticInst class into its own. This change pulls the instruction decoding machinery (including caches) out of the StaticInst class and puts it into its own class. This has a few intrinsic benefits. First, the StaticInst code, which has gotten to be quite large, gets simpler. Second, the code that handles decode caching is now separated out into its own component and can be looked at in isolation, making it easier to understand. I took the opportunity to restructure the code a bit which will hopefully also help. Beyond that, this change also lays some ground work for each ISA to have its own, potentially stateful decode object. We'd be able to include less contextualizing information in the ExtMachInst objects since that context would be applied at the decoder. Also, the decoder could "know" ahead of time that all the instructions it's going to see are going to be, for instance, 64 bit mode, and it will have one less thing to check when it decodes them. Because the decode caching mechanism has been separated out, it's now possible to have multiple caches which correspond to different types of decoding context. Having one cache for each element of the cross product of different configurations may become prohibitive, so it may be desirable to clear out the cache when relatively static state changes and not to have one for each setting. Because the decode function is no longer universally accessible as a static member of the StaticInst class, a new function was added to the ThreadContexts that returns the applicable decode object.
2011-09-09 11:30:01 +02:00
};
ISA,CPU: Generalize and split out the components of the decode cache. This will allow it to be specialized by the ISAs. The existing caching scheme is provided by the BasicDecodeCache in the GenericISA namespace and is built from the generalized components. --HG-- rename : src/cpu/decode_cache.cc => src/arch/generic/decode_cache.cc
2012-05-26 22:45:12 +02:00
} // namespace DecodeCache
Decode: Pull instruction decoding out of the StaticInst class into its own. This change pulls the instruction decoding machinery (including caches) out of the StaticInst class and puts it into its own class. This has a few intrinsic benefits. First, the StaticInst code, which has gotten to be quite large, gets simpler. Second, the code that handles decode caching is now separated out into its own component and can be looked at in isolation, making it easier to understand. I took the opportunity to restructure the code a bit which will hopefully also help. Beyond that, this change also lays some ground work for each ISA to have its own, potentially stateful decode object. We'd be able to include less contextualizing information in the ExtMachInst objects since that context would be applied at the decoder. Also, the decoder could "know" ahead of time that all the instructions it's going to see are going to be, for instance, 64 bit mode, and it will have one less thing to check when it decodes them. Because the decode caching mechanism has been separated out, it's now possible to have multiple caches which correspond to different types of decoding context. Having one cache for each element of the cross product of different configurations may become prohibitive, so it may be desirable to clear out the cache when relatively static state changes and not to have one for each setting. Because the decode function is no longer universally accessible as a static member of the StaticInst class, a new function was added to the ThreadContexts that returns the applicable decode object.
2011-09-09 11:30:01 +02:00
#endif // __CPU_DECODE_CACHE_HH__
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