| 摘要 |
Program routines normally requiring windowed register allocation using conventional assembly code generation in a compiler are examined for eligibility for a wrapper routine optimization procedure in which wrapper routine assembly code instructions are generated in response to the application of high level programming language instructions specifying routines. If not eligible, the compiler generates assembly code instructions in a conventional way, allocating windowed registers to each routine. If the routine is eligible for wrapper routine optimization, the routine is further examined to determine whether the routine includes tail routine calls only or calls within the body of the routine. If the former, the routine is examined to determine whether local stack usage is required. For a routine having tail routine calls only and a requirement of local stack usage, wrapper routine assembly code instructions of a first type are generated. If the routine includes tail calls only and no requirement for local storage, wrapper routine assembly code instructions of a second type are generated. If the routine incorporates one or more calls within the body thereof, the routine is further examined to determine whether a live register is required over any of the calls. If so, wrapper routine assembly code instructions of a third type are generated. If the routine incorporates calls within the body thereof and a live register is not required over any call, wrapper routine assembly code instructions of a fourth type are generated.
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