tracei

Traces machine instructions.

SYNTAX

tracei [var | at addr | in func] [if expression] [{cmd; cmd ...}]
[after n] [pset set_name | set_definition]

DESCRIPTION

Use the tracei command to trace machine instructions when the program is executed.

The first option listed in the synopsis (var | at addr | in func) must come first on the command line; you can specify the other options, if you include them, in any order.

var is the name of a variable. The value of the variable is displayed whenever it changes. If the variable is an array or a parallel variable, values are displayed if the value of any element changes. This form of the command slows execution considerably. You cannot specify both a variable and a location.

at addr causes a message to be printed immediately prior to the execution of the specified address.

in func causes tracing information to be printed only while executing inside the specified procedure or function.

if expression specifies the logical condition, if any, under which tracing is to occur. The logical condition can be any expression that evaluates to true or false. Unless combined with the at addr syntax, this form of tracei slows execution considerably.

{cmd; cmd ...} specifies the actions, if any, that are to accompany the trace. Put the actions in braces. The actions can be Prism commands; if you include multiple commands, separate them with semicolons.

after n specifies how many times a trigger condition (for example, reaching a program location) is to occur before the trace occurs. The default is 1. If you specify both a condition and an after count, Prism checks the condition first.

When tracing instructions, Prism follows all procedure calls down.

When issued in MP Prism, this command can take a pset qualifier. If used with a qualifier, it applies to the pset you specify. If used without a qualifier, it applies to the current pset. See " Using Pset Qualifiers" for more information on pset qualifiers.

EXAMPLES

tracei 0x1000 after 3

traces the instruction at address 1000 (hex) the third time it is reached.

tracei 0x500 if a == 0

traces the instruction at address 500 (hex) if a is equal to 0.