Intel ITANIUM ARCHITECTURE - SOFTWARE DEVELOPERS VOLUME 3 REV 2.3, Manual

Page: 1313 / 1898

Volume 4: Base IA-32 Instruction Reference 4:11
Base IA-32 Instruction Reference 2
This section lists all IA-32 instructions and their behavior in the Itanium System
Environment and IA-32 System Environments on an processor based on the Itanium
architecture. Unless noted otherwise all IA-32 and MMX technology and SSE
instructions operate as defined in the
Intel
®
64 and IA-32 Architectures Software
Developer’s Manual .
This volume describes the complete IA-32 Architecture instruction set, including the
integer, floating-point, MMX technology and SSE technology, and system instructions.
The instruction descriptions are arranged in alphabetical order. For each instruction, the
forms are given for each operand combination, including the opcode, operands
required, and a description. Also given for each instruction are a description of the
instruction and its operands, an operational description, a description of the effect of
the instructions on flags in the EFLAGS register, and a summary of the exceptions that
can be generated.
For all IA-32 the following relationships hold:
• Writes – Writes of any IA-32 general purpose, floating-point or SSE, MMX
technology registers by IA-32 instructions are reflected in the Itanium registers
defined to hold that IA-32 state when IA-32 instruction set completes execution.
• Reads – Reads of any IA-32 general purpose, floating-point or SSE, MMX
technology registers by IA-32 instructions see the state of the Itanium registers
defined to hold the IA-32 state after entering the IA-32 instruction set.
• State mappings – IA-32 numeric instructions are controlled by and reflect their
status in FCW, FSW, FTW, FCS, FIP, FOP, FDS and FEA. On exit from the IA-32
instruction set, Itanium numeric status and control resources defined to hold IA-32
state reflect the results of all IA-32 prior numeric instructions in FCR, FSR, FIR and
FDR. Itanium numeric status and control resources defined to hold IA-32 state are
honored by IA-32 numeric instructions when entering the IA-32 instruction set.
2.1 Additional Intel
®
Itanium
®
Faults
The following fault behavior is defined for all IA-32 instructions in the Itanium System
Environment:
• IA-32 Faults – All IA-32 faults are performed as defined in the Intel
®
64 and
IA-32 Architectures Software Developer’s Manual , unless otherwise noted.
IA-32 faults are delivered on the IA_32_Exception interruption vector.
• IA-32 GPFault – Null segments are signified by the segment descriptor register’s
P-bit being set to zero. IA-32 memory references through DSD, ESD, FSD, and GSD
with the P-bit set to zero result in an IA-32 GPFault.
• Itanium Low FP Reg Fault – If PSR.dfl is 1, execution of any IA-32 MMX
technology, SSE or floating-point instructions results in a Disabled FP Register fault
(regardless of whether FR2-31 is referenced).
• Itanium High FP Reg Fault – If PSR.dfh is 1, execution of the first target IA-32
instruction following an
br.ia
or
rfi
results in a Disabled FP Register fault
(regardless of whether FR32-127 is referenced).