From 48c0b3ffcaef15aeac7b239e769bcc795b943bec Mon Sep 17 00:00:00 2001 From: Pavel Pisa Date: Thu, 7 Feb 2019 19:20:52 +0100 Subject: Implemented simple indication of presence of memory location in the cache. Signed-off-by: Pavel Pisa --- qtmips_machine/cache.cpp | 20 +++++++++++++++----- qtmips_machine/cache.h | 7 ++++++- qtmips_machine/memory.cpp | 2 +- qtmips_machine/memory.h | 2 +- qtmips_machine/physaddrspace.cpp | 2 +- qtmips_machine/physaddrspace.h | 2 +- 6 files changed, 25 insertions(+), 10 deletions(-) (limited to 'qtmips_machine') diff --git a/qtmips_machine/cache.cpp b/qtmips_machine/cache.cpp index 94e314b..e327d7b 100644 --- a/qtmips_machine/cache.cpp +++ b/qtmips_machine/cache.cpp @@ -51,6 +51,7 @@ Cache::Cache(MemoryAccess *m, const MachineConfigCache *cc, unsigned memory_acc dt = nullptr; replc.lfu = nullptr; replc.lru = nullptr; + p_change_counter = new std::uint32_t(0); // Skip any other initialization if cache is disabled if (!cc->enabled()) @@ -89,6 +90,7 @@ Cache::Cache(MemoryAccess *m, const MachineConfigCache *cc, unsigned memory_acc } Cache::~Cache(){ + delete p_change_counter; if (dt != nullptr) { for (unsigned i = 0; i < cnf.associativity(); i++) { if (dt[i]) { @@ -216,15 +218,17 @@ const MachineConfigCache &Cache::config() const { return cnf; } -enum LocationStatus Cache::location_status(std::uint32_t address) { +enum LocationStatus Cache::location_status(std::uint32_t address) const { + address = address >> 2; unsigned ssize = cnf.blocks() * cnf.sets(); std::uint32_t tag = address / ssize; std::uint32_t index = address % ssize; std::uint32_t row = index / cnf.blocks(); for (unsigned indx = 0; indx < cnf.associativity(); indx++) { - if (dt[indx][row].valid && dt[indx][row].tag != tag) { - if (dt[indx][row].dirty) + if (dt[indx][row].valid && dt[indx][row].tag == tag) { + if (dt[indx][row].dirty && + cnf.write_policy() == MachineConfigCache::WP_BACK) return (enum LocationStatus)(LOCSTAT_CACHED | LOCSTAT_DIRTY); else return (enum LocationStatus)LOCSTAT_CACHED; @@ -282,8 +286,10 @@ bool Cache::access(std::uint32_t address, std::uint32_t *data, bool write, std:: struct cache_data &cd = dt[indx][row]; // Verify if we are not replacing - if (cd.valid && cd.tag != tag) + if (cd.valid && cd.tag != tag) { kick(indx, row); + (*p_change_counter)++; + } // Update statistics and otherwise read from memory if (cd.valid) { @@ -300,8 +306,10 @@ bool Cache::access(std::uint32_t address, std::uint32_t *data, bool write, std:: miss_read++; emit miss_update(miss()); update_statistics(); - for (unsigned i = 0; i < cnf.blocks(); i++) + for (unsigned i = 0; i < cnf.blocks(); i++) { cd.data[i] = mem->read_word(base_address(tag, row) + (4*i)); + (*p_change_counter)++; + } } // Update replc @@ -327,6 +335,8 @@ bool Cache::access(std::uint32_t address, std::uint32_t *data, bool write, std:: } emit cache_update(indx, row, cd.valid, cd.dirty, cd.tag, cd.data); + if (changed) + (*p_change_counter)++; return changed; } diff --git a/qtmips_machine/cache.h b/qtmips_machine/cache.h index 4d8cb6d..6027bd3 100644 --- a/qtmips_machine/cache.h +++ b/qtmips_machine/cache.h @@ -64,7 +64,11 @@ public: void reset(); // Reset whole state of cache const MachineConfigCache &config() const; - enum LocationStatus location_status(std::uint32_t address); + enum LocationStatus location_status(std::uint32_t address) const; + + inline std::uint32_t get_change_counter() const { + return *p_change_counter; + } signals: void hit_update(unsigned) const; void miss_update(unsigned) const; @@ -72,6 +76,7 @@ signals: void cache_update(unsigned associat, unsigned set, bool valid, bool dirty, std::uint32_t tag, const std::uint32_t *data) const; private: + std::uint32_t* p_change_counter; MachineConfigCache cnf; MemoryAccess *mem; unsigned access_pen_r, access_pen_w; diff --git a/qtmips_machine/memory.cpp b/qtmips_machine/memory.cpp index e1d65c4..79ac949 100644 --- a/qtmips_machine/memory.cpp +++ b/qtmips_machine/memory.cpp @@ -122,7 +122,7 @@ std::uint32_t MemoryAccess::read_ctl(enum AccessControl ctl, std::uint32_t offse void MemoryAccess::sync() { } -enum LocationStatus MemoryAccess::location_status(std::uint32_t address) { +enum LocationStatus MemoryAccess::location_status(std::uint32_t address) const { return LOCSTAT_NONE; } diff --git a/qtmips_machine/memory.h b/qtmips_machine/memory.h index 8c8a319..33caf46 100644 --- a/qtmips_machine/memory.h +++ b/qtmips_machine/memory.h @@ -60,7 +60,7 @@ public: std::uint32_t read_ctl(enum AccessControl ctl, std::uint32_t offset) const; virtual void sync(); - virtual enum LocationStatus location_status(std::uint32_t offset); + virtual enum LocationStatus location_status(std::uint32_t offset) const; protected: virtual bool wword(std::uint32_t offset, std::uint32_t value) = 0; diff --git a/qtmips_machine/physaddrspace.cpp b/qtmips_machine/physaddrspace.cpp index 9053e48..bb01b60 100644 --- a/qtmips_machine/physaddrspace.cpp +++ b/qtmips_machine/physaddrspace.cpp @@ -66,7 +66,7 @@ std::uint32_t PhysAddrSpace::rword(std::uint32_t address) const { return p_range->mem_acces->read_word(address - p_range->start_addr); } -enum LocationStatus PhysAddrSpace::location_status(std::uint32_t address) { +enum LocationStatus PhysAddrSpace::location_status(std::uint32_t address) const { const RangeDesc *p_range = find_range(address); if (p_range == nullptr) return LOCSTAT_ILLEGAL; diff --git a/qtmips_machine/physaddrspace.h b/qtmips_machine/physaddrspace.h index 6d9f91c..c6f5e81 100644 --- a/qtmips_machine/physaddrspace.h +++ b/qtmips_machine/physaddrspace.h @@ -57,7 +57,7 @@ public: bool insert_range(MemoryAccess *mem_acces, std::uint32_t start_addr, std::uint32_t last_addr, bool move_ownership); bool remove_range(MemoryAccess *mem_acces); void clean_range(std::uint32_t start_addr, std::uint32_t last_addr); - enum LocationStatus location_status(std::uint32_t offset); + enum LocationStatus location_status(std::uint32_t offset) const; private: class RangeDesc { public: -- cgit v1.2.3