Intel ITANIUM ARCHITECTURE - SOFTWARE DEVELOPERS MANUAL VOLUME 1 REV 2.3 Manual page 1429

FFREE—Free Floating-point Register
Opcode
DD C0+i
Description
Sets the tag in the FPU tag register associated with register ST(i) to empty (11B). The
contents of ST(i) and the FPU stack-top pointer (TOP) are not affected.
Operation
TAG(i)  11B;
FPU Flags Affected
C0, C1, C2, C3 undefined.
Floating-point Exceptions
None.
Additional Itanium System Environment Exceptions
Itanium Reg Faults Disabled FP Register Fault if PSR.dfl is 1.
Protected Mode Exceptions
#NM
Real Address Mode Exceptions
#NM
Virtual 8086 Mode Exceptions
#NM
Volume 4: Base IA-32 Instruction Reference
Instruction Description
FFREE ST( i ) Sets tag for ST( i ) to empty
EM or TS in CR0 is set.
EM or TS in CR0 is set.
EM or TS in CR0 is set.
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