
Chapter 11
Windows NT Alpha
The following sections specify the Privileged Architecture Library (PALcode) instructions that are required to support a Windows NT Alpha system.
11.1 Unprivileged Windows NT Alpha PALcode
The unprivileged PALcode instuctions provide support for system operations and may be called from both kernel and user modes.
Table 11–1 : Unprivileged Windows NT Alpha PALcode Instruction Summary
Mnemonic | Operation and description |
bpt | Breakpoint trap (standard |
| The bpt instruction raises a breakpoint general exception to the kernel, setting a |
| USER_BREAKPOINT breakpoint type. |
callkd | Call kernel debugger |
| The callkd instruction raises a breakpoint general exception to the kernel, set- |
| ting the breakpoint type with the value supplied as an input parameter. |
callsys | System service call |
| The callsys instruction raises a system service call exception to the kernel. Call- |
| sys switches to kernel mode if necessary, builds a trap frame on the kernel |
| stack, and then enters the kernel at the kernel system service exception handler. |
gentrap | Generate a trap |
| The gentrap instruction generates a software general exception that raises an |
| exception code to the current thread. The exception code is generated from a |
| trap number that is specified as an input parameter. Gentrap is used to raise |
| |
| tions. |
|
|