2002-08-14 Nathan Sidwell * doc/invoke.texi (-a): Remove documentation. (-fprofile-arcs): Remove reference to -a, -ax options. * doc/gcov.texi (Gcov Data Files): Data might be merged. --- gcc/doc/gcov.texi.jj 2001-11-15 11:38:19.000000000 +0100 +++ gcc/doc/gcov.texi 2002-08-22 11:48:48.000000000 +0200 @@ -388,7 +388,7 @@ built with the GCC @option{-fprofile-arc separate @file{.da} file is created for each source file compiled with this option, and the name of the @file{.da} file is stored as an absolute pathname in the resulting object file. This path name is -derived from the source file name by substituting a @file{.da} suffix. +derived from the object file name by substituting a @file{.da} suffix. The format of the @file{.da} file is fairly simple. The first 8-byte number is the number of counts in the file, followed by the counts --- gcc/doc/invoke.texi.jj 2002-08-08 17:55:08.000000000 +0200 +++ gcc/doc/invoke.texi 2002-08-22 11:46:49.000000000 +0200 @@ -2831,20 +2831,6 @@ analysis program @code{gprof}. You must the source files you want data about, and you must also use it when linking. -@cindex @code{tcov} -@item -a -@opindex a -Generate extra code to write profile information for basic blocks, which will -record the number of times each basic block is executed, the basic block start -address, and the function name containing the basic block. If @option{-g} is -used, the line number and filename of the start of the basic block will also be -recorded. If not overridden by the machine description, the default action is -to append to the text file @file{bb.out}. - -This data could be analyzed by a program like @code{tcov}. Note, -however, that the format of the data is not what @code{tcov} expects. -Eventually GNU @code{gprof} should be extended to process this data. - @item -Q @opindex Q Makes the compiler print out each function name as it is compiled, and @@ -2877,18 +2863,7 @@ optimization and code generation options 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. @@ -2898,11 +2873,6 @@ executed. When an arc is the only exit 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