| 摘要 |
A system and method for efficient architectural register liveness analysis and register usage reduction. A compiler within a computing system maintains a master liveness vector for each instruction in a program code and a path liveness vector for each path within a predetermined control flow graph (CFG). Predetermined required paths from an earlier compiler stage are used to find force paths, which are used to reduce the number of times a control block (CB) is processed. Upon completion of the liveness analysis, the compiler finds an instruction within the program code where a chosen register previously dead is now live. The compiler identifies allocation code paths from this instruction, wherein each path terminates at an instruction wherein the chosen register is dead for the first time in the allocation code path. The compiler subsequently replaces the chosen register with a determined dead register.
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