Powerpc 750Gx-Specific Registers; Instruction Address Breakpoint Register (Iabr) - IBM PowerPC 750GX User Manual

User's Manual
IBM PowerPC 750GX and 750GL RISC Microprocessor

2.1.2 PowerPC 750GX-Specific Registers

This section describes registers that are defined for the 750GX but are not included in the PowerPC Architec-
ture.

2.1.2.1 Instruction Address Breakpoint Register (IABR)

The Instruction Address Breakpoint Register (IABR) supports the instruction address breakpoint exception.
When this exception is enabled, instruction fetch addresses are compared with an effective address stored in
the IABR. If the word specified in the IABR is fetched, the instruction breakpoint handler is invoked. The
instruction that triggers the breakpoint does not execute before the handler is invoked. For more information,
see Section 4.5.14, Instruction Address Breakpoint Exception (0x01300), on page 173. The IABR can be
accessed with mtspr and mfspr using the SPR 1010.
0 1 2 3 4 5 6
Bits Field Name
0:29 Address
30 BE
31 TE
Programming Model
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Address
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Word address to be compared.
Breakpoint enabled. Setting this bit indicates that breakpoint checking is to be done.
Translation enabled. An IABR match is signaled if this bit matches MSR[IR].
Description
BE TE
gx_02.fm.(1.2)
March 27, 2006