• 7.1: Overview of Runtime Environments

    • Stanford University: Keith Schwarz's "Runtime Environments" URL

      Read this handout, which discusses data representations and their organization in memory for a program. After semantic analysis, intermediate representations are encoded. This is the last step of the "front-end" of the compilation process. The relationship of front ends to back ends can be many-to-one or one-to-many. In the former case, a single back end is used for several languages, each handled by its own front end. In the latter case, one front end handles the input, source language, and the back end is used for several target machines, each having its own back end.

    • Stanford University: Keith Schwarz's "Runtime Environments Slides" URL

      Read the functions of IR generation on slides 6 and 7. Some requirements for IR generation are on slide 8. Encoding of primitive types and arrays are discussed on slides 19 through 37 for additional coverage. 

      Scope of a variable is the lexical area of a program in which the variable can be used. Extent, or lifetime, is the period of time that a variable exists.

      See slides 38 through 118 for a discussion of the stack, activation trees, closure and coroutines, and parameter passing.

    • University of California, Berkeley: Paul Hilfinger's "Introduction to Runtime Organization" URL

      Read these notes. In this presentation, IR is treated as part of code generation, and it has a lot of detail on the run-time encoding for procedures and functions.