document -fno-guess-branch-probability option
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@ -1,9 +1,14 @@
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2001-01-17 Aldy Hernandez <aldyh@redhat.com>
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* invoke.texi (-fno-guess-branch-probability): New option.
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Wed Jan 17 13:26:34 2001 Richard Kenner <kenner@vlsi1.ultra.nyu.edu>
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* combine.c (try_combine): Don't set i3_subst_into_i2 for
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case of making new double-word constant.
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Revert last change: instead just test i3_subst_into_i2.
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>>>>>>> 1.9022
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2001-01-17 Jakub Jelinek <jakub@redhat.com>
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* config/i386/i386.md (cmpqi_minus_1): Use {b} for QImode operation.
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@ -244,7 +244,8 @@ in the following sections.
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-finline-functions -finline-limit=@var{n} -fkeep-inline-functions @gol
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-fkeep-static-consts -fmove-all-movables @gol
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-fno-default-inline -fno-defer-pop @gol
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-fno-function-cse -fno-inline -fno-math-errno -fno-peephole @gol
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-fno-function-cse -fno-guess-branch-probability
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-fno-inline -fno-math-errno -fno-peephole @gol
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-fomit-frame-pointer -foptimize-register-move @gol
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-foptimize-sibling-calls -freduce-all-givs @gol
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-fregmove -frename-registers @gol
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@ -3123,6 +3124,15 @@ branch is mostly to take, the @samp{REG_BR_PROB} values are used to
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exactly determine which path is taken more often.
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@end ifset
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@item -fno-guess-branch-probability
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Sometimes gcc will opt to guess branch probabilities when none are
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available from either profile directed feedback (@samp{-fprofile-arcs})
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or @samp(__builtin_expect). In a hard real-time system, people don't
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want different runs of the compiler to produce code that has different
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behavior; minimizing non-determinism is of paramount import. This
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switch allows users to reduce non-determinism, possibly at the expense
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of inferior optimization.
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@item -fstrict-aliasing
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Allows the compiler to assume the strictest aliasing rules applicable to
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the language being compiled. For C (and C++), this activates
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