KernelDebugRef - Operator Precedence: Difference between revisions

Latest revision as of 23:13, 3 May 2025

Reprint Courtesy of International Business Machines Corporation, © International Business Machines Corporation

Kernel Debugger Reference
Introduction Installing the Kernel Debugger The T Terminal Emulator Entering the Debugger Expressions Operator Precedence Binary Operators Unary Operators Numbers Strings Symbol Files Using Kernel Debugger Commands The Breakpoint (BP) Command Breakpoint Commands External Commands Using Default Commands External Debugger Commands Setting Useful Breakpoints Debugging Kernel Device Drivers Debugging VM Start Sessions Debugging a Remote System Notices

The precedence of the operators has been changed to be more like C.

If two or more operators have the same precedence, the expression is evaluated from left to right. C evaluates unary operators from right to left, which is more intuitive and easier to use. Expressions such as poi #60:133 must be written as poi (#60:133) because of the way the debugger handles unary operators.

( )
| :
. # % %% - ! NOT SEG OFF BY WO DW POI PORT WPORT (all unary operators)
* / MOD
+ -
> < >= <=
== !=
AND XOR OR
&& ||

@@ Line 2: / Line 2: @@
 {{KernelDebugRef}}
-The following operators evaluate the relationship of two arguments:
+The precedence of the operators has been changed to be more like '''C'''.
-* '''( )''' Parentheses, used to change order of evaluation
+If two or more operators have the same precedence, the expression is evaluated from left to right. '''C''' evaluates unary operators from right to left, which is more intuitive and easier to use. Expressions such as '''poi #60:133''' must be written as '''poi (#60:133)''' because of the way the debugger handles unary operators.
-* ''':''' Address binder, binds segment/selector and offsets
-* '''*''' Multiplication
+# '''( )'''
-* '''/''' Division
+# '''| :'''
-* '''MOD''' Modulo (remainder)
+# '''. # % %% - ! NOT SEG OFF BY WO DW POI PORT WPORT''' (all unary operators)
-* '''+''' Addition
+# '''* / MOD'''
-* '''-''' Subtraction
+# '''+ -'''
-* '''>''' Greater than relational operator
+# '''> < >= <='''
-* '''<''' Less than relational operator
+# '''== !='''
-* '''>=''' Greater than or equal to relational operator
+# '''AND XOR OR'''
-* '''<=''' Less than or equal to relational operator
+# '''&& ||'''
-* '''==''' Equal to operator
-* '''!=''' Not equal to relational operator
-* '''AND''' Bitwise AND
-* '''XOR''' Bitwise exclusive OR
-* '''OR''' Bitwise inclusive OR
-* '''&&''' Logical AND
-* '''||''' Logical OR