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[Bug tree-optimization/83262] SELECT CASE slower than IF/ELSE


https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83262

--- Comment #4 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
The speed depends on the optimization level, SELECT CASE being the fastest with
-O1

-O0

           GOTO costs totally     4.667 (s)
    SELECT CASE costs totally     4.578 (s)
        IF-Goto costs totally     4.986 (s)
      IF-noGoto costs totally     5.734 (s)
        IF-ELSE costs totally     5.731 (s)

-O1

           GOTO costs totally     1.231 (s)
    SELECT CASE costs totally     1.181 (s)
        IF-Goto costs totally     1.826 (s)
      IF-noGoto costs totally     1.738 (s)
        IF-ELSE costs totally     1.668 (s)

-O2

           GOTO costs totally     3.721 (s)
    SELECT CASE costs totally     4.274 (s)
        IF-Goto costs totally     1.517 (s)
      IF-noGoto costs totally     1.482 (s)
        IF-ELSE costs totally     1.525 (s)

-O3

           GOTO costs totally     3.755 (s)
    SELECT CASE costs totally     4.234 (s)
        IF-Goto costs totally     1.497 (s)
      IF-noGoto costs totally     1.522 (s)
        IF-ELSE costs totally     1.537 (s)

-Ofast

           GOTO costs totally     3.280 (s)
    SELECT CASE costs totally     4.324 (s)
        IF-Goto costs totally     1.526 (s)
      IF-noGoto costs totally     1.534 (s)
        IF-ELSE costs totally     1.513 (s)

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