Optimisation questions

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Article #52858

#52858

From: Ajay Shah
Date: Sun, 17 May 1992 21:08

22 lines
980 bytes

Can I count on gcc -O to replace

    for (i=0; i<N; i++) {
        x += z[i]; y += z[i];
    }

by something like

    for (i=0; i<N; i++) {
        tmp = z[i]; x += tmp; y += tmp;
    }

?

How does one learn more about ``improvements'' to code quality which
are irrelevant with modern compilers, and those which still help the
compiler?

        -ans.
-- 

Ajay Shah, (213)749-8133, ajayshah@usc.edu

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From: ajayshah@almaak.usc.edu (Ajay Shah)
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Subject: Optimisation questions
Date: 17 May 1992 14:08:45 -0700
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