Optimizing Translation Out of SSA Using Renaming Constraints

Static Single Assignment form is an intermediate representation that uses instructions to merge values at each confluent point of the control flow graph. instructions are not machine instructions and must be renamed back to move instructions when translating out of SSA form. Without a coalescing algorithm, the out of SSA translation generates many move instructions. Leung and George [8] use a SSA form for programs represented as native machine instructions, including the use of machine dedicated registers. For this purpose, they handle renaming constraints thanks to a pinning mechanism. Pinning arguments and their corresponding definition to a common resource is also a very attractive technique for coalescing variables. In this paper, extending this idea, we propose a method to reduce the -related copies during the out of SSA translation, thanks to a pinningbased coalescing algorithm that is aware of renaming constraints. We implemented our algorithm in the STMicroelectronics Linea...

• Type: Conference
• Year: 2004
• Where: CGO
• Authors: Fabrice Rastello, François de Ferrière, Christophe Guillon
• Keywords: CGO 2004, Coalescing Algorithm, Machine Instructions, Software Engineering, SSA Form