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--- invoke.texi.orig Tue Feb 17 10:54:05 1998
+++ invoke.texi Tue Aug 11 13:29:38 1998
@@ -115,7 +115,7 @@
@smallexample
-fsyntax-only -pedantic -pedantic-errors
-w -W -Wall -Waggregate-return -Wbad-function-cast
--Wcast-align -Wcast-qual -Wchar-subscript -Wcomment
+-Wcast-align -Wcast-qual -Wchar-subscripts -Wcomment
-Wconversion -Werror -Wformat
-Wid-clash-@var{len} -Wimplicit -Wimplicit-int
-Wimplicit-function-declarations -Wimport -Winline
@@ -153,6 +153,7 @@
-frerun-cse-after-loop -fschedule-insns
-fschedule-insns2 -fstrength-reduce -fthread-jumps
-funroll-all-loops -funroll-loops
+-fmove-all-movables -freduce-all-givs -frerun-loop-opt
-O -O0 -O1 -O2 -O3
@end smallexample
@@ -2284,6 +2285,47 @@
Perform the optimization of loop unrolling. This is done for all loops
and usually makes programs run more slowly. @samp{-funroll-all-loops}
implies @samp{-fstrength-reduce} as well as @samp{-frerun-cse-after-loop}.
+
+@item -fmove-all-movables
+Forces all invariant computations in loops to be moved
+outside the loop.
+This option is provided primarily to improve performance
+for some Fortran code, though it might improve code written
+in other languages.
+
+@emph{Note:} When compiling programs written in Fortran,
+this option is enabled by default.
+
+Analysis of Fortran code optimization and the resulting
+optimizations triggered by this option, and the
+@samp{-freduce-all-givs} and @samp{-frerun-loop-opt}
+options as well, were
+contributed by Toon Moene (@code{toon@@moene.indiv.nluug.nl}).
+
+Please let us (@code{fortran@@gnu.ai.mit.edu})
+know how use of these options affects
+the performance of your production code.
+We're very interested in code that runs @emph{slower}
+when these options are @emph{enabled}.
+
+@item -freduce-all-givs
+Forces all general-induction variables in loops to be
+strength-reduced.
+This option is provided primarily to improve performance
+for some Fortran code, though it might improve code written
+in other languages.
+
+@emph{Note:} When compiling programs written in Fortran,
+this option is enabled by default.
+
+@item -frerun-loop-opt
+Runs loop optimizations a second time.
+This option is provided primarily to improve performance
+for some Fortran code, though it might improve code written
+in other languages.
+
+@emph{Note:} When compiling programs written in Fortran,
+this option is enabled by default.
@item -fno-peephole
Disable any machine-specific peephole optimizations.
|
