| Brian Gaeke | f36e2d5 | 2004-06-02 19:12:38 +0000 | [diff] [blame^] | 1 | |
| 2 | =pod |
| 3 | |
| 4 | =head1 NAME |
| 5 | |
| 6 | gccas - optimizing LLVM assembler |
| 7 | |
| 8 | =head1 SYNOPSIS |
| 9 | |
| 10 | gccas [options] filename |
| 11 | |
| 12 | =head1 DESCRIPTION |
| 13 | |
| 14 | The B<gccas> utility takes an LLVM assembly file generated by the |
| 15 | L<llvm-gcc|llvm-gcc> or L<llvm-g++|llvm-g++> front-ends and converts |
| 16 | it into an LLVM bytecode file. It is primarily used by the GCC |
| 17 | front end, and as such, attempts to mimic the interface provided |
| 18 | by the default system assembler so that it can act as a "drop-in" |
| 19 | replacement. |
| 20 | |
| 21 | B<gccas> performs a number of optimizations on the input program, |
| 22 | including but not limited to: promotion of stack values to SSA |
| 23 | registers; elimination of dead globals, function arguments, code, |
| 24 | and types; tail-call elimination; loop-invariant code motion; global |
| 25 | common-subexpression elimination; and sparse conditional constant |
| 26 | propagation. |
| 27 | |
| 28 | =head1 OPTIONS |
| 29 | |
| 30 | =over |
| 31 | |
| 32 | =item B<--help> |
| 33 | |
| 34 | Print a summary of command line options. |
| 35 | |
| 36 | =item B<-o> F<filename> |
| 37 | |
| 38 | Specify the name of the output file which will hold the assembled bytecode. |
| 39 | |
| 40 | =item B<--disable-inlining> |
| 41 | |
| 42 | Disable the inlining pass. By default, it is enabled. |
| 43 | |
| 44 | =item B<--disable-opt> |
| 45 | |
| 46 | Disable all assembler-time optimization passes. |
| 47 | |
| 48 | =item B<--enable-correct-eh-support> |
| 49 | |
| 50 | Instruct the B<-lowerinvoke> pass to insert code for correct exception handling |
| 51 | support. This is expensive and is by default omitted for efficiency. |
| 52 | |
| 53 | =item B<--stats> |
| 54 | |
| 55 | Print statistics. |
| 56 | |
| 57 | =item B<--time-passes> |
| 58 | |
| 59 | Record the amount of time needed for each pass and print it to standard |
| 60 | error. |
| 61 | |
| 62 | =item B<--verify> |
| 63 | |
| 64 | Verify each pass result. |
| 65 | |
| 66 | =back |
| 67 | |
| 68 | =head1 EXIT STATUS |
| 69 | |
| 70 | If B<gccas> succeeds, it will exit with an exit status of 0. |
| 71 | Otherwise, if an error occurs, it will exit with a non-zero exit |
| 72 | status. |
| 73 | |
| 74 | =head1 SEE ALSO |
| 75 | |
| 76 | L<llvm-as>, L<gccld> |
| 77 | |
| 78 | =head1 AUTHORS |
| 79 | |
| 80 | Maintained by the LLVM Team (L<http://llvm.cs.uiuc.edu>). |
| 81 | |
| 82 | =cut |
| 83 | |