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Diffstat (limited to 'gcc/doc/passes.texi')
| -rw-r--r-- | gcc/doc/passes.texi | 51 |
1 files changed, 0 insertions, 51 deletions
diff --git a/gcc/doc/passes.texi b/gcc/doc/passes.texi index ad07f60..6bbc61c 100644 --- a/gcc/doc/passes.texi +++ b/gcc/doc/passes.texi @@ -237,57 +237,6 @@ the second conditional test. The source code for this pass is in @file{jump.c}. This optimization is only performed if @option{-fthread-jumps} is enabled. -@cindex SSA optimizations -@cindex Single Static Assignment optimizations -@opindex fssa -@item -Static Single Assignment (SSA) based optimization passes. The -SSA conversion passes (to/from) are turned on by the @option{-fssa} -option (it is also done automatically if you enable an SSA optimization pass). -These passes utilize a form called Static Single Assignment. In SSA form, -each variable (pseudo register) is only set once, giving you def-use -and use-def chains for free, and enabling a lot more optimization -passes to be run in linear time. -Conversion to and from SSA form is handled by functions in -@file{ssa.c}. - -@opindex de -The option @option{-de} causes a debugging dump of the RTL code after -this pass. This dump file's name is made by appending @samp{.ssa} to -the input file name. -@itemize @bullet -@cindex SSA Conditional Constant Propagation -@cindex Conditional Constant Propagation, SSA based -@cindex conditional constant propagation -@opindex fssa-ccp -@item -SSA Conditional Constant Propagation. Turned on by the @option{-fssa-ccp} -option. This pass performs conditional constant propagation to simplify -instructions including conditional branches. This pass is more aggressive -than the constant propagation done by the CSE and GCSE passes, but operates -in linear time. - -@opindex dW -The option @option{-dW} causes a debugging dump of the RTL code after -this pass. This dump file's name is made by appending @samp{.ssaccp} to -the input file name. - -@cindex SSA DCE -@cindex DCE, SSA based -@cindex dead code elimination -@opindex fssa-dce -@item -SSA Aggressive Dead Code Elimination. Turned on by the @option{-fssa-dce} -option. This pass performs elimination of code considered unnecessary because -it has no externally visible effects on the program. It operates in -linear time. - -@opindex dX -The option @option{-dX} causes a debugging dump of the RTL code after -this pass. This dump file's name is made by appending @samp{.ssadce} to -the input file name. -@end itemize - @cindex common subexpression elimination @cindex constant propagation @item |