FRSTOR
Usage: FRSTOR src Modifies flags: The C0, C1, C2, C3 flags are loaded.
Loads the FPU state (operating environment and register stack) from the memory area specified with the 'src' operand. This state data is typically written to the specified memory location by a previous FSAVE/FNSAVE instruction.
Save/Restore Floating-Point State
FSAVE mem ; 9B DD /6 [8086,FPU]
FNSAVE mem ; DD /6 [8086,FPU]
FRSTOR mem ; DD /4 [8086,FPU]
FSAVE saves the entire floating-point unit state, including all the information saved by FSTENV ( FSTENV) plus the contents of all the registers, to a 94 or 108 byte area of memory (depending on the CPU mode). FRSTOR restores the floating-point state from the same area of memory. Label
FNSAVE does the same as FSAVE, without first waiting for pending floating-point exceptions to clear.
If one or more unmasked exception bits are set in the new FPU status word, a floating-point exception will be generated. To avoid raising exceptions when loading a new operating environment, clear all the exception flags in the FPU status word that is being loaded.
Example:
frstor Label