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authorPavel Pisa <pisa@cmp.felk.cvut.cz>2019-02-07 19:20:52 +0100
committerPavel Pisa <pisa@cmp.felk.cvut.cz>2019-02-07 19:20:52 +0100
commit48c0b3ffcaef15aeac7b239e769bcc795b943bec (patch)
tree69443cff9a486515c9fe95b08fec02e183ed2ba2 /qtmips_machine
parent1126b91af5bd2d4477b3e78e8c648b3a512b24f7 (diff)
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Implemented simple indication of presence of memory location in the cache.
Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Diffstat (limited to 'qtmips_machine')
-rw-r--r--qtmips_machine/cache.cpp20
-rw-r--r--qtmips_machine/cache.h7
-rw-r--r--qtmips_machine/memory.cpp2
-rw-r--r--qtmips_machine/memory.h2
-rw-r--r--qtmips_machine/physaddrspace.cpp2
-rw-r--r--qtmips_machine/physaddrspace.h2
6 files changed, 25 insertions, 10 deletions
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: