diff options
Diffstat (limited to 'src/cpu/decode_cache.hh')
-rw-r--r-- | src/cpu/decode_cache.hh | 84 |
1 files changed, 10 insertions, 74 deletions
diff --git a/src/cpu/decode_cache.hh b/src/cpu/decode_cache.hh index 6ed820332..473340586 100644 --- a/src/cpu/decode_cache.hh +++ b/src/cpu/decode_cache.hh @@ -37,9 +37,11 @@ #include "config/the_isa.hh" #include "cpu/static_inst.hh" -typedef StaticInstPtr (*DecodeInstFunc)(TheISA::ExtMachInst); +namespace TheISA +{ + class Decoder; +} -template <DecodeInstFunc decodeInstFunc> class DecodeCache { private: @@ -63,92 +65,26 @@ class DecodeCache /// Update the small cache of recent lookups. /// @param recentest The most recent result; - void - update(PageIt recentest) - { - recent[1] = recent[0]; - recent[0] = recentest; - } - - void - addPage(Addr addr, DecodePage *page) - { - Addr page_addr = addr & ~(TheISA::PageBytes - 1); - typename PageMap::value_type to_insert(page_addr, page); - update(pageMap.insert(to_insert).first); - } + void update(PageIt recentest); + void addPage(Addr addr, DecodePage *page); public: /// Constructor - DecodePages() - { - recent[0] = recent[1] = pageMap.end(); - } + DecodePages(); /// Attempt to find the DecodePage 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. - DecodePage * - getPage(Addr addr) - { - Addr page_addr = addr & ~(TheISA::PageBytes - 1); - - // 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; - } - } - - // Actually look in the has_map. - PageIt it = pageMap.find(page_addr); - if (it != pageMap.end()) { - update(it); - return it->second; - } - - // Didn't find an existing page, so add a new one. - DecodePage *newPage = new DecodePage; - addPage(page_addr, newPage); - return newPage; - } + DecodePage *getPage(Addr addr); } decodePages; public: /// Decode a machine instruction. /// @param mach_inst The binary instruction to decode. /// @retval A pointer to the corresponding StaticInst object. - StaticInstPtr - decode(ExtMachInst mach_inst, Addr addr) - { - // Try to find a matching address based table of instructions. - DecodePage *page = decodePages.getPage(addr); - - // Use the table to decode the instruction. It will fall back to other - // mechanisms if it needs to. - Addr offset = addr & (TheISA::PageBytes - 1); - StaticInstPtr si = page->insts[offset]; - if (si && (si->machInst == mach_inst)) - return si; - - InstMap::iterator iter = instMap.find(mach_inst); - if (iter != instMap.end()) { - si = iter->second; - page->insts[offset] = si; - return si; - } - - si = decodeInstFunc(mach_inst); - instMap[mach_inst] = si; - page->insts[offset] = si; - return si; - } + StaticInstPtr decode(TheISA::Decoder * const decoder, + ExtMachInst mach_inst, Addr addr); }; #endif // __CPU_DECODE_CACHE_HH__ |