NAME

       llvm-opt-report - generate optimization report from YAML

SYNOPSIS

       llvm-opt-report [options] [input]

DESCRIPTION

       llvm-opt-report is a tool to generate an optimization report from YAML optimization record
       files.

       You need to create an input YAML optimization record file before running llvm-opt-report.

       It provides information on the execution time, memory usage, and  other  details  of  each
       optimization pass.

          $ clang -c foo.c -o foo.o -O3 -fsave-optimization-record

       Then,  you  create  a  report using the llvm-opt-report command with the YAML optimization
       record file foo.opt.yaml as input.

          $ llvm-opt-report foo.opt.yaml -o foo.lst

       foo.lst is the generated optimization report.

          < foo.c
           1          | void bar();
           2          | void foo() { bar(); }
           3          |
           4          | void Test(int *res, int *c, int *d, int *p, int n) {
           5          |   int i;
           6          |
           7          | #pragma clang loop vectorize(assume_safety)
           8     V4,1 |   for (i = 0; i < 1600; i++) {
           9          |     res[i] = (p[i] == 0) ? res[i] : res[i] + d[i];
          10          |   }
          11          |
          12  U16     |   for (i = 0; i < 16; i++) {
          13          |     res[i] = (p[i] == 0) ? res[i] : res[i] + d[i];
          14          |   }
          15          |
          16 I        |   foo();
          17          |
          18          |   foo(); bar(); foo();
             I        |   ^
             I        |                 ^
          19          | }
          20          |

       Symbols printed on the left side of the program indicate what  kind  of  optimization  was
       performed.  The meanings of the symbols are as follows:

       • I: The function is inlined.

       • U: The loop is unrolled. The following number indicates the unroll factor.

       • V:  The  loop  is  vectorized.  The following numbers indicate the vector length and the
         interleave factor.

       NOTE:
          If a specific line of code is output twice, it means that the  same  optimization  pass
          was  applied  to that line of code twice, and the pass was able to further optimize the
          code on the second iteration.

OPTIONS

       If input is “-” or omitted, llvm-opt-report reads from standard input. Otherwise, it  will
       read from the specified filename.

       If the -o option is omitted, then llvm-opt-report will send its output to standard output.
       If the -o option specifies “-”, then the output will also be sent to standard output.

       --help Display available options.

       --version
              Display the version of this program.

       --format=<string>
              The format of the optimization record file.  The Argument is one of the following:

              • yaml

              • yaml-strtab

              • bitstream

       --no-demangle
              Do not demangle function names.

       -o=<string>
              Output file.

       -r=<string>
              Root for relative input paths.

       -s     Do not include vectorization factors, etc.

EXIT STATUS

       llvm-opt-report returns 0 on success. Otherwise, an error message is printed  to  standard
       error, and the tool returns 1.

AUTHOR

       Maintained by the LLVM Team (https://llvm.org/).

COPYRIGHT

       2003-2023, LLVM Project