1:38
Volume 1, Part 1: Execution Environment
3.3
Instruction Encoding Overview
Each instruction is categorized into one of six types; each instruction type may be
executed on one or more execution unit types.
lists the instruction types and
the execution unit type on which they are executed.
Three instructions are grouped together into 128-bit sized and aligned containers called
bundles
. Each bundle contains three 41-bit
instruction slots
and a 5-bit template
field. The format of a bundle is depicted in
.
During execution, architectural
stops
in the program indicate to the hardware that one
or more instructions before the stop may have certain kinds of resource dependencies
with one or more instructions after the stop. A stop is present after each slot having a
double line to the right of it in
. For example, template 00 has no stops, while
template 03 has a stop after slot 1 and another after slot 2.
In addition to the location of stops, the template field specifies the mapping of
instruction slots to execution unit types. Not all possible mappings of instructions to
units are available.
indicates the defined combinations. The three rightmost
columns correspond to the three instruction slots in a bundle. Listed within each column
is the execution unit type controlled by that instruction slot.
Table 3-9.
Relationship between Instruction Type and Execution Unit Type
Instruction Type
Description
Execution Unit Type
A
Integer ALU
I-unit or M-unit
I
Non-ALU integer
I-unit
M
Memory
M-unit
F
Floating-point
F-unit
B
Branch
B-unit
L+X
Extended
I-unit/B-unit
Figure 3-15. Bundle Format
12
7
87 86
46 45
5
4
0
instruction slot 2
instruction slot 1
instruction slot 0
template
41
41
41
5
Table 3-10.
Template Field Encoding and Instruction Slot Mapping
Template
Slot 0
Slot 1
Slot 2
00
M-unit
I-unit
I-unit
01
M-unit
I-unit
I-unit
02
M-unit
I-unit
I-unit
03
M-unit
I-unit
I-unit
04
M-unit
L-unit
X-unit
a
05
M-unit
L-unit
X-unit
06
07
08
M-unit
M-unit
I-unit
09
M-unit
M-unit
I-unit
0A
M-unit
M-unit
I-unit
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 ...