-qreport

Purpose

Produces listing files that show how sections of code have been optimized.

A listing file is generated with a .lst suffix for each source file that is listed on the command line. When you specify -qreport with an option that enables automatic vectorization, the listing file shows annotated Fortran code listing and a summary of how program loops are optimized. The report also includes diagnostic information about why specific loops cannot be vectorized. For example, when -qreport is specified with -qsimd, messages are provided to identify non-stride-one references that prevent loop vectorization.

Syntax

Option:

@PROCESS:

@PROCESS REPORT[({HOTLIST}...)] | NOREPORT

Defaults

-qnoreport

Parameters

hotlist: When -qreport=hotlist is in effect, produces a pseudo-Fortran listing that shows how loops are transformed, to assist you in tuning the performance of all loops. This report is only produced if -qhot is in effect.

Specifying -qreport with no suboptions is equivalent to -qreport=hotlist.

Usage

To generate a loop transformation listing, you must specify -qreport with one of the following options:

-qhot
-O3 or higher

To generate data reorganization information, specify -qreport with -qlto or -O5.

To generate a list of aggressive loop transformations on loop nests in the LOOP TRANSFORMATION SECTION of the listing file, use the optimization level of -qhot=level=2 together with -qreport.

Examples

To compile myprogram.f so the compiler listing includes a report showing how loops are optimized, enter the following command:

xlf -O3 -qreport myprogram.f