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31 #ifndef __CPU_O3_RAS_HH__
32 #define __CPU_O3_RAS_HH__
35 #include "arch/isa_traits.hh"
38 /** Return address stack class, implements a simple RAS. */
42 /** Creates a return address stack, but init() must be called prior to
47 /** Initializes RAS with a specified number of entries.
48 * @param numEntries Number of entries in the RAS.
50 void init(unsigned numEntries);
54 /** Returns the top address on the RAS. */
56 { return addrStack[tos]; }
58 /** Returns the index of the top of the RAS. */
62 /** Pushes an address onto the RAS. */
63 void push(const Addr &return_addr);
65 /** Pops the top address from the RAS. */
68 /** Changes index to the top of the RAS, and replaces the top address with
70 * @param top_entry_idx The index of the RAS that will now be the top.
71 * @param restored_target The new target address of the new top of the RAS.
73 void restore(unsigned top_entry_idx, const Addr &restored_target);
76 /** Increments the top of stack index. */
78 { if (++tos == numEntries) tos = 0; }
80 /** Decrements the top of stack index. */
82 { tos = (tos == 0 ? numEntries - 1 : tos - 1); }
84 /** The RAS itself. */
85 std::vector<Addr> addrStack;
87 /** The number of entries in the RAS. */
90 /** The number of used entries in the RAS. */
93 /** The top of stack index. */
97 #endif // __CPU_O3_RAS_HH__