Intel ITANIUM ARCHITECTURE - SOFTWARE DEVELOPERS MANUAL VOLUME 1 REV 2.3 Manual page 1498

FXCH—Exchange Register Contents (Continued)
Real Address Mode Exceptions
#NM
Virtual 8086 Mode Exceptions
#NM
4:196
EM or TS in CR0 is set.
EM or TS in CR0 is set.
Volume 4: Base IA-32 Instruction Reference