Topic: program execution

Summary

Ultimately programs are executed on a machine. The machine finds a continuous sequential path through the program's code. It determines its own next instruction. Once one processor is started it just keeps on going until explicitly stopped. It is this path, the moment to moment, irreversible change in data and state, that is the program's true meaning. A large part of this path is controlling memory references and address computations.

Interpreters are processors which "execute" a data representation. In data flow programs, execution is by the confluence of data at nodes. (cbb 5/80)

Subtopic: sequence of instructions

Quote: the distinguishing feature of a computer is that it determines its own next instruction [»bellCG_1971]

QuoteRef: cbb_1973 ;;7/14/74 formally any program at a given time is == to a linear straightforward no loops, no branches program

Subtopic: complexity of execution

Quote: even though a program may appear graceful, it looks like a Rube Goldberg machine when executed by hand [»dennDC_1978a]

Subtopic: static program vs. dynamic data

Quote: execution of a program concerns two information streams: a constant one, the program, and a varying one, the data

Quote: the behavior of a system is the time pattern of its data structures [»bellCG_1971]

Quote: a Modula-3 program is a computation on locations of digital components [»cardL_1991]

Subtopic: read-only code

Quote: executable code should not be modified; was a big clarity problem with machine code [»dijkEW5_1965]

Subtopic: result despite alternatives

Quote: evaluation in Icon seeks for successful results in the presence of alternative values [»grisRE4_1979]

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Group: expression evaluation   (5 topics, 97 quotes)
Group: machine model   (13 topics, 206 quotes)
Group: types of programming languages   (29 topics, 611 quotes)

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