User Guide

iv Contents
AMD64 Technology 24592—Rev. 3.15—November 2009
MXCSR Register ..........................................................117
Other Data Registers .......................................................120
rFLAGS Registers .........................................................120
4.4 Operands ................................................................121
Data Types ...............................................................121
Operand Sizes and Overrides.................................................123
Operand Addressing .......................................................123
Data Alignment ...........................................................123
Integer Data Types.........................................................124
Floating-Point Data Types ...................................................126
Floating-Point Number Representation .........................................127
Floating-Point Number Encodings ............................................130
Floating-Point Rounding ....................................................132
4.5 Instruction Summary—Integer Instructions .....................................133
Syntax ..................................................................133
Data Transfer .............................................................135
Data Conversion ..........................................................139
Data Reordering...........................................................140
Arithmetic ...............................................................145
Shift ....................................................................152
Compare.................................................................153
Logical ..................................................................155
Save and Restore State......................................................156
4.6 Instruction Summary—Floating-Point Instructions................................156
Syntax ..................................................................157
Data Transfer .............................................................157
Data Conversion ..........................................................162
Data Reordering...........................................................165
Arithmetic ...............................................................166
Compare.................................................................171
Logical ..................................................................174
4.7 Instruction Effects on Flags ..................................................175
4.8 Instruction Prefixes ........................................................175
Supported Prefixes.........................................................175
Special-Use and Reserved Prefixes ............................................176
Prefixes That Cause Exceptions ..............................................176
4.9 Feature Detection..........................................................176
4.10 Exceptions ...............................................................177
General-Purpose Exceptions .................................................177
SIMD Floating-Point Exception Causes ........................................178
SIMD Floating-Point Exception Priority........................................182
SIMD Floating-Point Exception Masking .......................................184
4.11 Saving, Clearing, and Passing State............................................188
Saving and Restoring State ..................................................188
Parameter Passing .........................................................188
Accessing Operands in MMX™ Registers ......................................188
4.12 Performance Considerations .................................................189