Method and apparatus for guest return address stack emulation supporting speculation

• Main Author: ABDALLAH MOHAMMAD
• Format: Patent
• Language: Chinese; English
• Published: 19.02.2019
• Subjects: CALCULATING; COMPUTING; COUNTING; ELECTRIC DIGITAL DATA PROCESSING; PHYSICS

The application discloses a method and apparatus for guest return address stack emulation supporting speculation. A microprocessor implemented method for maintaining a guest return address stack in anout-of- order microprocessor pipeline is disclosed. The method comprises mapping a plurality of instructions in a guest address space into a corresponding plurality of instructions in a native address space. For each function call instruction in the native address space fetched during execution, the method also comprises performing the following: (a) pushing a current entry into a guest return address stack (GRAS) responsive to a function call, wherein the GRAS is maintained at the fetch stage of the pipeline, and wherein the current entry comprises information regarding both a guest target return address and a corresponding native target return address associated with the function call; (b) popping the current entry from the GRAS in response to processing a return instruction; and (c) fetching instructions from