2:40
Volume 2, Part 1: System State and Programming Model
3.3.5.6
Interruption Instruction Previous Address (IIPA – CR22)
For Itanium instructions, IIPA records the last successfully executed instruction bundle
address. For IA-32 instructions, IIPA records the byte granular virtual instruction
address zero extended to 64-bits of the faulting or trapping IA-32 instruction. In the
case of a fault, IIPA does not report the address of the last successfully executed IA-32
instruction, but rather the address of the faulting IA-32 instruction. IIPA preserves bits
3:0 for byte aligned IA-32 instruction addresses.
The IIPA can be used by software to locate the address of the instruction bundle or
IA-32 instruction that raised a trap or the instruction executed prior to a fault or
interruption. In the case of a branch related trap, IIPA points to the instruction bundle
which contained the branch instruction that raised the trap, while IIP points to the
target of the branch.
When an instruction successfully executes without a fault, and the PSR.ic bit was 1 prior
to instruction execution, it becomes the “last successfully executed instruction.” On
interruptions, IIPA contains the address of the last successfully executed instruction
bundle or IA-32 instruction, if PSR.ic was 1 prior to the interruption. Note that
execution of an
rfi
instruction with PSR.ic equal to 0, but which sets PSR.ic to 1 does
not update IIPA, since PSR.ic was zero prior to instruction execution.
When PSR.ic is one, accesses to IIPA cause an Illegal Operation fault. When PSR.ic is
zero, IIPA is not updated by hardware and can be read and written by software. This
permits low-level code to preserve IIPA across interruptions.
If the PSR.ic bit is explicitly cleared, e.g., by using
rsm
, then the contents of IIPA are
undefined. Only when the PSR.ic bit is cleared by an interruption is the value of IIPA
defined. It may point at the instruction which caused a trap, or at the instruction just
prior to a faulting instruction, at an earlier instruction that became defined by some
prior interruption, or by a move to IIPA instruction when PSR.ic was zero.
If the PSR.ic bit is explicitly set, e.g., by using
ssm
, then the contents of IIPA are
undefined until the PSR.ic bit has been serialized and an interruption occurs.
During instruction set transitions the following boundary cases exist:
• On faults taken on the first IA-32 instruction after a
br.ia
or
rfi
, IIPA records the
faulting IA-32 instruction address.
• On
br.ia
traps, IIPA records the address of the trapping instruction bundle.
• On faults taken on the first Itanium instruction after leaving the IA-32 instruction
set, due to a
jmpe
or interruption, IIPA contains the address of the
jmpe
instruction
or the interrupted IA-32 instruction.
• On
jmpe
Data Debug, Single Step and Taken Branch traps, IIPA contains the
address of the
jmpe
instruction.
, all 64-bits of the IIPA must be implemented regardless of the
size of the physical and virtual address space supported by the processor model (see
“Unimplemented Address Bits” on page 2:73
Figure 3-13. Interruption Instruction Previous Address (IIPA – CR22)
63
0
IIPA
64
Summary of Contents for ITANIUM ARCHITECTURE - SOFTWARE DEVELOPERS VOLUME 3 REV 2.3
Page 1: ......
Page 11: ...x Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Page 13: ...1 2 Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Page 33: ...1 22 Volume 1 Part 1 Introduction to the Intel Itanium Architecture ...
Page 57: ...1 46 Volume 1 Part 1 Execution Environment ...
Page 147: ...1 136 Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Page 149: ...1 138 Volume 1 Part 2 About the Optimization Guide ...
Page 191: ...1 180 Volume 1 Part 2 Predication Control Flow and Instruction Stream ...
Page 230: ......
Page 248: ...236 Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Page 250: ...2 2 Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Page 264: ...2 16 Volume 2 Part 1 Intel Itanium System Environment ...
Page 380: ...2 132 Volume 2 Part 1 Interruptions ...
Page 398: ...2 150 Volume 2 Part 1 Register Stack Engine ...
Page 486: ...2 238 Volume 2 Part 1 IA 32 Interruption Vector Descriptions ...
Page 750: ...2 502 Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Page 754: ...2 506 Volume 2 Part 2 About the System Programmer s Guide ...
Page 796: ...2 548 Volume 2 Part 2 Interruptions and Serialization ...
Page 808: ...2 560 Volume 2 Part 2 Context Management ...
Page 842: ...2 594 Volume 2 Part 2 Floating point System Software ...
Page 850: ...2 602 Volume 2 Part 2 IA 32 Application Support ...
Page 862: ...2 614 Volume 2 Part 2 External Interrupt Architecture ...
Page 870: ...2 622 Volume 2 Part 2 Performance Monitoring Support ...
Page 891: ......
Page 1099: ...3 200 Volume 3 Instruction Reference padd Interruptions Illegal Operation fault ...
Page 1295: ...3 396 Volume 3 Resource and Dependency Semantics ...
Page 1296: ......
Page 1302: ...402 Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Page 1494: ...4 192 Volume 4 Base IA 32 Instruction Reference FWAIT Wait See entry for WAIT ...
Page 1647: ...Volume 4 Base IA 32 Instruction Reference 4 345 ROL ROR Rotate See entry for RCL RCR ROL ROR ...
Page 1884: ...4 582 Volume 4 IA 32 SSE Instruction Reference ...
Page 1885: ...Index Intel Itanium Architecture Software Developer s Manual Rev 2 3 Index ...
Page 1886: ...Index Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Page 1898: ...INDEX Index 12 Index for Volumes 1 2 3 and 4 ...