PASO — Program Analysis Summary Output
- Overview
- Usage
- JSON File Format
- Export File Structure
- Structures Breakdown
- Variable and Function References
- General Attributes
- Export File Structure Schema
Overview
Beginning with version 17.7, PGI compilers have the ability to export information gathered from the internal representation (IR) of various compilation stages in an organized, machine readable text format. This Program Analysis Summary Output (PASO) feature is enabled using the -Msummary compiler option. The data provides a detailed summary of the program’s internal structure, spanning all the files that make up a project. PASO data contains detailed information about every function call site, every place where a variable is declared, read, or modified, OpenACC and OpenMP regions, and more.
Usage
PASO data export is enabled using the -Msummary option during compilation. PASO is supported on all PGI compilers for Linux x86-64 and Windows using the proprietary PGI back end.
By default the compilers embed the export data into the executable as a data section. This creates a section ".IPXPORT" which can be extracted using the pgextract command:
pgextract (executable) -cz -name ".IPXPORT" (output filename)
JSON File Format
PASO uses JSON (JavaScript Object Notatation) format to export the internal data structures. The core syntax of JSON formatting is summarized below.
Structures: delimited by { }
Elements: "name":"data"(,)
Arrays: ["data","data","data"]
Correctly formatted JSON consists of a main structure encapsulating various pairs of named elements. A structure or array can take the place of any "data" element.
{
"name":"example",
"array":["one","two"],
"structure":{
"name":"substruct",
"value":"10"
}
}
Export File Structure
Within an PASO export file, there are a variety of structures. These include:
- Data type definition:
- Contains the internal name, size, and prototype of a structure, union, or derived type.
- File:
- Represents an object file, with its source if available. Contains data about the file and its contents, and any functions and modules.
- Module:
- A Fortran module, contains any module functions.
- Function:
- Represents a function, method, procedure, or a Fortran subroutine, program, or subprogram. Contains information about variables, calls, and assignments
- Variable:
- Contains metadata, type information, bindings to functions where it is used or modified, and default values
- Binding records:
- Contains information about an instance where a variable is used, modified, or assigned.
- Call records:
- Record of a function call, arguments passed, and additional binding information for variables passed as arguments.
- Attributes:
- Various properties of a function or variable covering a wide variety of additional information.
Structures Breakdown
Data Type Structures Breakdown
{
"type":"derived D60", Type name
"size":"16", Size in bytes
"structure":"{int;int;int;int;}" Layout
}
File Structures Breakdown
"file1":{ Generated unique file ID
"name":"example.o", Object filename
"source":"example.c", Source file
"newobjectname":"_example.o", Result of recompilation
"library":"lib/xyz.ipl", Library containing object
"compiler":"PGI 16.10", Compiler version info
"language":"c", Source compilation type
"modules":{module structures}, Struct containing modules
"functions":{function structures} Struct of functions defined
}
Function Structures Breakdown
"testfunc":{ Name
"name":"_testfunc", Mangled name
"uname":"testfunc", Original name
"module":"m1", Containing module
"host program":{progref}, Parent program reference
"lineno":"10", Source line number
"size":"3", Size/weight of function
"type":"(int)(*int,char)", Function prototype
"attributes":[…], Function attributes
"loops":"2", Loops in function
"max loop nest":"2", How many levels of nesting
"direct calls":"1", Direct calls to this function
"indirect calls":"1" Indirect/aliased calls
"parameters":{…}, Parameter variables
"variables":{…}, Local variables
"common":[…], Common block vars used
"globals":[…], Global variables used
"nonlocal used":[…], Vars whose values are used
"nonlocal modified":[…], Vars that are modified
"callers":[…], Names of calling functions
"calls":[…], Ordered list of call records
"modules used":[…] List of modules used here
}
Modules Stuctures Breakdown
"testmodule":{ Name of module
"testfunc":{…}, Function definition
"testfunc2":{…} Etc.
}
Variables Structures Breakdown
{
"name":"x", Name within current scope
"type":"unsigned int", Full data type
"bindings":[binding structures], List of binding references
"attributes":[…] List of attributes
}
Bindings Structures Breakdown
Binding references mean different things in different cases. A parameter is bound to any variables or constants that are passed to it, and any variables from which they are derived. A variable can also be bound to an assignment from another variable, a constant, or an expression. Bindings are a part of the variable that contains them.
{
"type":"assignment/argument", Type of binding
"variable":{var} Variable derived from
"constant":"100", Constant assigned
"expr" Runtime calculated value
}
Variable and Function References
All references within an PASO export file include a structure containing the file, function, module, host program, or variable name as needed. For example:
{"file":"file1","function":"main","variable":"var"}
{"file":"file3","module":"m","function":"func"}
{"file":"file2","program":"prog","function":"func2"}
General Attributes
addrtkn Address taken alias Is an alias of another assigned Value will be changed called Known path from main canrecompile Have source information common Part of a common block const Constant value constvar Is not changed dummy Dummy argument definition extern Can be called from another file f90pointer Fortran pointer fileglobal Global to current file fromlib From a shared library globalinit Called before main haveinfo Info obtained from original source file inline Declared as inline inlineable Can be inlined inmodule From a Fortran module intrin Intrinsic function main Main program or function not-called Never explicitly called acc Function contains or call inside ACC region omp Function contains or call inside OMP region
Export File Structure Schema
{
"datatypes":[list of datatype structures],
"files":{
"file1":{
(metadata)
"functions":{
"func1":{
(metadata)
"variables":{
"var1":{
"type":"xyz",
"bindings":[…],
"attributes":[…]
},
…
},
"calls":[…]
},
…
}
},
…
}
}
