Dynamic translation of tree-instructions into VLIWs

We describe an approach and its implementation for the dynamic translation of programs
represented as sequences of tree-instructions into very-long instruction words (VLIWs)
suitable for execution on wide-issue processors. Tree-instructions are characterized by not
reflecting the organization of any processor implementation, whereas VLIWs incorporate
implementation-specific features. Tree-instructions are dynamically translated, during
instruction cache reloading/accessing, to fit processor implementations constraints. Such
a translation is performed without the need for checking dependencies between primitive
instructions because tree-instructions consist of operations executable simultaneously.
This approach allows executing the same object-code and delivers scalable performance
on implementations with varying resources, including superscalar and VLIW-based ones,
thus solving one of the most critical objections to the adoption of the VLIW paradigm in
general-purpose architectures.

By: Jaime H. Moreno

Published in: RC20505 in 1996


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