Calculation Precision Analysis Functions

The calculation precision analysis tool locates the precision differences of the Fortran, C, and C++ languages caused by x86 and Kunpeng instructions.

Command Function

Locates the precision differences of the Fortran, C, and C++ languages caused by x86 and Kunpeng instructions.

Calculation precision analysis can identify the KML_MATH functions used in your application. If your application uses these functions but is not linked to the KML_MATH library, you will be advised to use the KML_MATH library. For details about the supported functions, see Kunpeng Math Library.

Syntax

Compilation and instrumentation:

devkit advisor precision [-h | --help] {-instrument | --instrument} {-c COMMAND COMMANDS | --commands COMMANDS} {-p PROJECT | --project PROJECT} [-e ENTRY | --entry ENTRY] [-a | --all] [-v VARIABLE | --variable VARIABLE] [-d DEPTH | --depth DEPTH] [-L | --loops] [-D DATABASE| --database DATABASE] [-b BLACK_LIST | --black-list BLACK_LIST] [-l {0,1,2,3} | --log-level {0,1,2,3}] [--set-timeout TIMEOUT]

Log difference analysis:

devkit advisor precision [-h | --help] {-analysis | --analysis} {-i INPUT_LOG | --input INPUT_LOG} [-o OUTPUT_PATH | --output OUTPUT_PATH] [-l {0,1,2,3} | --log-level {0,1,2,3}] [--set-timeout TIMEOUT]

To use the calculation precision analysis tool, you need to perform compilation and instrumentation on the different platforms (Kunpeng and x86). After the instrumentation is complete, analyze log differences.
Control the execution time of the instrumented binary to prevent excessive drive space usage caused by logs generated during long-running executions. For example, for the WRF application, select a test case with a lower resolution or limit the test case execution time after instrumentation.

Parameter Description

**Table 1** Compilation and instrumentation parameters
Parameter	Option	Description
-h/--help	-	(Optional) Obtains help information.
-instrument/--instrument	-	(Mandatory) Compilation and instrumentation mode.
-c/--commands	-	(Mandatory) Builds source code. If there are multiple build commands, separate them with semicolons (;) and enclose them with single quotation marks (') or double quotation marks ("). If a command contains spaces, enclose it with single or double quotation marks. Example: "make all" or "cd /home/test;make" NOTE: Do not run the cmake command directly. You need to run the command in advance. The source code build command in the command line tool does not support variable setting and environment variable export. Example: "CFLAGS='-O0 -g';make" or "export CFLAGS='-O0 -g';make"
-p/--project	-	(Mandatory) Absolute path to the project source code. Example: /home/test/project1/ or /home/project2/
-e/--entry	-	(Optional) Instrumentation entry file and the corresponding function. This parameter is mutually exclusive with -a/--all. Enter the relative path (specified by -p/--project) to the entry file in the project path. The file is used for compilation and cannot be the source file before preprocessing. The function is Main Program, Function, or Subroutine that exists in the specified Fortran file. NOTE: Each file and its function must be separated using a colon (:). Specify a single function of a single file. -e File_name:Function_name (for example, -e demo.f90:main) Specify multiple functions of a single file. Use commas (,) to separate the functions. -e File_name:Function_name_1,Function_name_2 (for example, -e demo.f90:main,func) Specify multiple files. Use multiple -e parameters to specify each file and function name (for example, -e demo.f90:main -e test.f90:func).
-a/--all	-	(Optional) Full instrumentation for trigonometric functions, complex numbers, and division. The supported types include the built-in complex type in Fortran and the built-in complex and std::complex types in C/C++. This parameter is mutually exclusive with -e/--entry, -v/--variable, and -d/--depth.
-v/--variable	-	(Optional) Parameter instrumentation mode for a specific variable. This parameter is mutually exclusive with -a/--all. When this parameter is specified, the instrumentation depth is forcibly set to 0.
-d/--depth	-	(Optional) Depth of continuous instrumentation from the entry function. The default value is 0. The value ranges from 0 to 99. This parameter is mutually exclusive with -a/--all.
-L/--loops	-	(Optional) Instrumentation inside loops. When this option is selected, the precision log file generated by running the executable file after instrumentation becomes larger. Properly arrange the instrumentation entry (entry file and function) and depth.
-D/--database	-	(Optional) Path to the compilation database. After you specify the path, incremental compilation will be performed. The compilation database file dev_compile_commands.json is generated by instrumentation using the calculation precision analysis tool for the first time.
-b/--black-list	-	(Optional) Files that do not participate in instrumentation. The value must be an absolute file path. The file specified by the -e parameter must not be included. Example: "/home/test/demo1.f90;/home/test/demo2.f90"
-l/--log-level	0/1/2/3	(Optional) Log level, which defaults to 1. 0: DEBUG 1: INFO 2: WARNING 3: ERROR
--set-timeout	-	(Optional) Timeout interval of a task, in minutes. If the execution duration exceeds the preset timeout interval, the task exits. By default, there is no timeout interval. The task will be executed until it is complete.

**Table 2** Parameters of log difference analysis modes
Parameter	Option	Description
-h/--help	-	(Optional) Obtains help information.
-analysis/--analysis	-	(Mandatory) Log difference analysis mode.
-i/--input	-	(Mandatory) Path to the log files or log file directories. The input sequence is Kunpeng logs first and then x86 logs. Example: "/home/kunpeng.log;/home/x86.log" or "/home/kunpeng/;/home/x86/"
-o/--output	-	(Optional) Directory for storing analysis result files. The default directory is the current directory.
-l/--log-level	0/1/2/3	(Optional) Log level, which defaults to 1. 0: DEBUG 1: INFO 2: WARNING 3: ERROR
--set-timeout	-	(Optional) Timeout interval of a task, in minutes. If the execution duration exceeds the preset timeout interval, the task exits. By default, there is no timeout interval. The task will be executed until it is complete.

Parent topic: Calculation Precision Analysis