Intel 64 and IA-32 Architectures Software Developers Manual Volume 1, Basic Architecture

Vol. 1 5-13
INSTRUCTION SET SUMMARY
FLDLN2 Load log
e
2
FLDL2T Load log
2
10
FLDLG2 Load log
10
2
5.2.6 x87 FPU Control Instructions
The x87 FPU control instructions operate on the x87 FPU register stack and save and
restore the x87 FPU state.
FINCSTP Increment FPU register stack pointer
FDECSTP Decrement FPU register stack pointer
FFREE Free floating-point register
FINIT Initialize FPU after checking error conditions
FNINIT Initialize FPU without checking error conditions
FCLEX Clear floating-point exception flags after checking for error
conditions
FNCLEX Clear floating-point exception flags without checking for error
conditions
FSTCW Store FPU control word after checking error conditions
FNSTCW Store FPU control word without checking error conditions
FLDCW Load FPU control word
FSTENV Store FPU environment after checking error conditions
FNSTENV Store FPU environment without checking error conditions
FLDENV Load FPU environment
FSAVE Save FPU state after checking error conditions
FNSAVE Save FPU state without checking error conditions
FRSTOR Restore FPU state
FSTSW Store FPU status word after checking error conditions
FNSTSW Store FPU status word without checking error conditions
WAIT/FWAIT Wait for FPU
FNOP FPU no operation
5.3 X87 FPU AND SIMD STATE MANAGEMENT
INSTRUCTIONS
Two state management instructions were introduced into the IA-32 architecture with
the Pentium II processor family:
FXSAVE Save x87 FPU and SIMD state
FXRSTOR Restore x87 FPU and SIMD state