For PR1152:

Update documentation to reflect addition of gccas functionality into opt.

llvm-svn: 33803

docs/CommandGuide/opt.pod

@@ -45,12 +45,57 @@ overwrite the output file and replace it with new bytecode.
 
 =item B<-help>
 
-Print a summary of command line options.
+Print a summary of command line options. 
 
 =item B<-o> I<filename>
 
 Specify the output filename.
 
+=item B<-{passname}>
+
+B<opt> provides the ability to run any of LLVM's optimization or analysis passes
+in any order. The B<-help> option lists all the passes available. The order in
+which the options occur on the command line are the order in which they are
+executed (within pass constraints). 
+
+=item B<-std-compile-opts>
+
+This is short hand for a standard list of I<compile time optimization> passes.
+This is typically used to optimize the output from the llvm-gcc front end. It
+might be useful for other front end compilers as well. To discover the full set
+of options available, use the following command:
+
+=over
+
+B<llvm-as < /dev/null | opt -std-compile-opts -disable-output -debug-pass=Arguments>
+
+=back
+
+=item B<-disable-inlining>
+
+This option is only meaningful when B<-std-compile-opts> is given. It simply
+removes the inlining pass from the standard list.
+
+=item B<-disable-opt>
+
+This option is only meaningful when B<-std-compile-opts> is given. It disables
+most, but not all, of the B<-std-compile-opts>. The ones that remain are
+B<-verify>, B<-lower-setjmp>, and B<-funcresolve>.
+
+=item B<-strip-debug>
+
+This option causes opt to strip debug information from the module before 
+applying other optimizations. It is essentially the same as B<-strip> but it
+ensures that stripping of debug information is done first.
+
+=item B<-verify-each>
+
+This option causes opt to add a verify pass after every pass otherwise specified
+on the command line (including B<-verify>).  This is useful for cases where it 
+is suspected that a pass is creating an invalid module but it is not clear which
+pass is doing it. The combination of B<-std-compile-opts> and B<-verify-each>
+can quickly track down this kind of problem.
+
 =item B<-profile-info-file> I<filename>
 
 Specify the name of the file loaded by the -profile-loader option.