Intel® VTune™ Profiler User Guide

User Guide

Contents

Debug Information for Linux* Application Binaries

Intel® VTune™
Profiler
 requires debug information for the binary files it analyzes to obtain accurate performance data and enable source analysis.

Debug Information for Performance Analysis

If your system and application modules have debug information, the
VTune
Profiler
 is able to provide full-scale statistics on call stacks, source data, function names, and so on. For example, you may use the Call Stack Mode on the filter toolbar to select the
User/system functions
 option and view data on both user and system functions.
If the
VTune
Profiler
 does not find debug information for the binaries, it statically identifies function boundaries and assigns hotspot addresses to generated pseudo names
func@
address
 for such functions, for example:
If a module is not found or the name of a function cannot be resolved, the
VTune
Profiler
 displays module identifiers within square brackets, for example:
[module]
.
If the debug information is absent, the
VTune
Profiler
 may not unwind the call stack and display it correctly in the
Call Stack
 pane. Additionally in some cases, it can take significantly more time to finalize the results for modules that do not have debug information.

Generate Debug Info in the DWARF Format

Compile your code using the
-g
 option that usually produces debugging information in the DWARF format.
If DWARF is not a default debugging information format for the compiler, or if you are using MinGW/Cygwin GCC*, use the
-gdwarf-
version
 option, for example:
-gdwarf-2
 or
-gdwarf-3
.

Generate Debug Info File for the ELF Format

You can create separate debug info files and link them with an executable/library via debug link or build ID. Please refer to the GNU* Binutils documentation for more details.
VTune
Profiler
 recognizes both types of linking:
  • If an executable file in the ELF format contains a build ID and has a separate debug info file with the name generated by the build ID, the
    VTune
    Profiler
     is able to find and validate the separate symbol file if proper search directories are set. While searching the symbol file, the
    VTune
    Profiler
     checks the
    .build-id
     subdirectory of each search directory for a file named
    hh/hhhhhhhhhhh.debug
     where
    hh
     is the first 2 hexadecimal characters of build ID and
    hhhhhhhhhhh
     is the remaining part.
  • If an executable file contains a debug link (specified in the
    .gnu_debuglink
     section) with a name of separate debug info file,
    VTune
    Profiler
     tries to find it.

Generate Debug Information for SYCL* Applications

To enable performance profiling and generate debug information for SYCL applications running on a GPU, make sure to compile your code with
-gline-tables-only
 and
-fdebug-info-for-profiling
 options.

Generate Debug Information for OpenMP* Offload Applications

When you build OpenMP* Offload applications with the
Intel® oneAPI
DPC++/C++
 Compiler
 or Intel Fortran compiler, compile your code with the
--info-for-profiling
 switch.
When using the Intel Fortran compiler to compile OpenMP Offload code, make sure to use the
-debug offload
 option.

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.