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invoke.texi (-profile-arcs): Remove references to -a and -ax. 

2002-10-29  Janis Johnson  <janis187@us.ibm.com>

	* doc/invoke.texi (-profile-arcs): Remove references to -a and -ax.

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Janis Johnson 2002-10-29 16:35:04 +00:00 committed by Janis Johnson
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@ -1,3 +1,7 @@
2002-10-29 Janis Johnson <janis187@us.ibm.com>
* doc/invoke.texi (-profile-arcs): Remove references to -a and -ax.
2002-10-29 Eric Botcazou <ebotcazou@libertysurf.fr>
* expr.c (expand_expr) [PLUS]: Don't use simplify_binary_operation;

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gcc/doc/invoke.texi
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@ -2933,18 +2933,7 @@ optimization and code generation options plus
Control Optimization}).
The other use of @option{-fprofile-arcs} is for use with @code{gcov},
when it is used with the @option{-ftest-coverage} option. GCC
supports two methods of determining code coverage: the options that
support @code{gcov}, and options @option{-a} and @option{-ax}, which
write information to text files. The options that support @code{gcov}
do not need to instrument every arc in the program, so a program compiled
with them runs faster than a program compiled with @option{-a}, which
adds instrumentation code to every basic block in the program. The
tradeoff: since @code{gcov} does not have execution counts for all
branches, it must start with the execution counts for the instrumented
branches, and then iterate over the program flow graph until the entire
graph has been solved. Hence, @code{gcov} runs a little more slowly than
a program which uses information from @option{-a} and @option{-ax}.
when it is used with the @option{-ftest-coverage} option.
With @option{-fprofile-arcs}, for each function of your program GCC
creates a program flow graph, then finds a spanning tree for the graph.
@ -2954,11 +2943,6 @@ executed. When an arc is the only exit or only entrance to a block, the
instrumentation code can be added to the block; otherwise, a new basic
block must be created to hold the instrumentation code.
This option makes it possible to estimate branch probabilities and to
calculate basic block execution counts. In general, basic block
execution counts as provided by @option{-a} do not give enough
information to estimate all branch probabilities.
@need 2000
@item -ftest-coverage
@opindex ftest-coverage