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-rw-r--r--inc/cache.h80
1 files changed, 39 insertions, 41 deletions
diff --git a/inc/cache.h b/inc/cache.h
index 0f15536..6f06466 100644
--- a/inc/cache.h
+++ b/inc/cache.h
@@ -3,77 +3,75 @@
#include "definitions.h"
#include "storage.h"
#include <array>
+#include <cmath>
#include <functional>
#include <ostream>
+/**
+ * Parse an address into a tag, index into the cache table, and a line
+ * offset.
+ * @param the address to be parsed
+ * @param the resulting tag
+ * @param the resulting index
+ * @param the resulting offset
+ */
+// clang-format off
+#define GET_FIELDS(a, t, i, o) \
+ *(t) = GET_MID_BITS(a, this->size + LINE_SPEC - this->ways, MEM_WORD_SPEC); \
+ *(i) = GET_MID_BITS(a, LINE_SPEC, this->size + LINE_SPEC - this->ways); \
+ *(o) = GET_LS_BITS(a, LINE_SPEC)
+// clang-format on
+
class Cache : public Storage
{
public:
/**
- * Constructor.
+nn * Constructor.
* @param The number of `lines` contained in memory. The total number of
* words is this number multiplied by LINE_SIZE.
* @param The next lowest level in storage. Methods from this object are
* called in case of a cache miss.
+ * @param The number of bits required to specify a line in this level of cache.
+ * @param The number of ways this line of cache uses, or the number of data addresses stored for
+ * certain address index.
* @param The number of clock cycles each access takes.
* @return A new cache object.
*/
- Cache(Storage *lower, int delay);
+ Cache(Storage *lower, unsigned int size, unsigned int ways, int delay);
~Cache();
- int
- write_word(void *, signed int, int) override;
- int
- write_line(void *, std::array<signed int, LINE_SIZE>, int) override;
- int
- read_line(void *, int, std::array<signed int, LINE_SIZE> &) override;
- int
- read_word(void *, int, signed int &) override;
-
- /**
- * Getter for the meta attribute.
- * TODO this doesn't seem like good object-oriented practice.
- * @return this->meta
- */
- std::array<std::array<int, 2>, L1_CACHE_LINES>
- get_meta() const;
+ int write_word(void *, signed int, int) override;
+ int write_line(void *, std::array<signed int, LINE_SIZE>, int) override;
+ int read_line(void *, int, std::array<signed int, LINE_SIZE> &) override;
+ int read_word(void *, int, signed int &) override;
private:
+ int process(
+ void *id, int address, std::function<void(int index, int offset)> request_handler) override;
/**
- * Helper for all access methods.
- * Calls `request_handler` when `id` is allowed to complete its
- * request cycle.
- * @param the source making the request
- * @param the address to write to
- * @param the function to call when an access should be completed
- */
- int
- process(void *id, int address, std::function<void(int index, int offset)> request_handler);
- /**
- * Returns OK if `id` is allowed to complete its request this cycle.
- * Handles cache misses, wait times, and setting the current id this
- * storage is serving.
- * @param the id asking for a resource
- * @return 1 if the access can be carried out this function call, 0 otherwise.
- */
- int
- is_access_cleared(void *id, int address);
- /**
- * Helper for is_access_cleared.
+ * Helper for process.
* Fetches `address` from a lower level of storage if it is not already
* present. The victim line is chosen/written back.
* @param the address that must be present in cache.
* @param 0 if the address is currently in cache, 1 if it is being fetched.
*/
- int
- is_address_missing(int address);
+ int is_address_missing(int address);
+ /**
+ * The number of bits required to specify a line in this level of cache.
+ */
+ unsigned int size;
+ /**
+ * The number of bits required to specify a way, or the number of data addresses stored for
+ * certain address index.
+ */
+ unsigned int ways;
/**
* An array of metadata about elements in `data`.
* If the first value of an element is negative, the corresponding
* element in `data` is invalid. If the most second value of an element
* is nonzero, the corresponding element in `data` is dirty.
*/
- std::array<std::array<int, 2>, L1_CACHE_LINES> meta;
+ std::vector<std::array<signed int, 3>> meta;
};
#endif /* CACHE_H_INCLUDED */