Volume 1, Part 1: Execution Environment
1:23
Execution Environment
3
The architectural state consists of registers and memory. The results of instruction
execution become architecturally visible according to a set of execution sequencing
rules. This chapter describes the application architectural state and the rules for
execution sequencing. See
for details on IA-32 instruction set execution.
3.1
Application Register State
The following is a list of the registers available to application programs (see
):
•
General Registers (GRs)
– General purpose 64-bit register file, GR0 - GR127.
IA-32 integer and segment registers are contained in GR8 - GR31 when executing
IA-32 instructions.
•
Floating-point Registers (FRs)
– Floating-point register file, FR0 - FR127. IA-32
floating-point and multi-media registers are contained in FR8 - FR31 when
executing IA-32 instructions.
•
Predicate Registers (PRs)
– Single-bit registers, used in predication and
branching, PR0 - PR63.
•
Branch Registers (BRs)
– Registers used in branching, BR0 - BR7.
•
Instruction Pointer (IP)
– Register which holds the bundle address of the
currently executing instruction, or byte address of the currently executing IA-32
instruction.
•
Current Frame Marker (CFM)
– State that describes the current general register
stack frame, and FR/PR rotation.
•
Application Registers (ARs)
– A collection of special-purpose registers.
•
Performance Monitor Data Registers (PMD)
– Data registers for performance
monitor hardware.
•
User Mask (UM)
– A set of single-bit values used for alignment traps,
performance monitors, and to monitor floating-point register usage.
•
Processor Identifiers (CPUID)
– Registers that describe processor
implementation-dependent features.
IA-32 application register state is entirely contained within the larger Itanium
application register set and is accessible by Itanium instructions. IA-32 instructions
cannot access the Itanium register set. See
Section 6.2.2, “IA-32 Application Register
for details on IA-32 register assignments.
3.1.1
Reserved and Ignored Registers and Fields
Registers which are not defined are either reserved or ignored. An access to a
reserved register
raises an Illegal Operation fault. A read of an
ignored register
returns zero. Software may write any value to an ignored register and the hardware will
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 ...