AMD Geode™ LX Processors Data Book 669
Instruction Set 33234H
FPATAN Function Eval: Tan-1(y/x) D9 F3 ST(1) <--- ATAN[ST(1) / TOS]; then pop TOS 269 - 354 3
FPREM Floating Point Remainder D9 F8 TOS <--- Rem[TOS / ST(1)] 53 - 208
FPREM1 Floating Point Remainder IEEE D9 F5 TOS <--- Rem[TOS / ST(1)] 53 - 208
FPTAN Function Eval: Tan(x) D9 F2 TOS <--- TAN(TOS); then push 1.0 onto stack 217 - 232 1, 2
FRNDINT Round to Integer D9 FC TOS <--- Round(TOS) 12
FRSTOR Load FPU Environment and Register DD [mod 100 r/m] Restore state 19 2
FSAVE Save FPU Environment and Register (9B)DD [mod 110 r/m] Wait, then save state 19 2
FNSAVE Save FPU Environment and Register DD [mod 110 r/m] Save state 19 2
FSCALE Floating Multiply by 2n D9 FD TOS <--- TOS × 2(ST(1)) 3
FSIN Function Evaluation: Sin(x) D9 FE TOS <--- SIN(TOS) 130 - 215 1
FSINCOS Function Eval.: Sin(x)& Cos(x) D9 FB temp <--- TOS;
TOS <--- SIN(temp); then
push COS(temp) onto stack
345 - 374 1, 2
FSQRT Floating Point Square Root D9 FA TOS <--- Square Root of TOS 13/54
FST Store FPU Register
FPU Stack DD [1101 0 n] ST(n) <--- TOS 1 3
64-bit Real DD [mod 010 r/m] M.DR <--- TOS 6
32-bit Real D9 [mod 010 r/m] M.SR <--- TOS 1/4
FSTP Store FPU Register, Pop
FPU Stack DB [1101 1 n] ST(n) <--- TOS; then pop TOS 1 3
80-bit Real DB [mod 111 r/m] M.XR <--- TOS; then pop TOS 1 3
64-bit Real DD [mod 011 r/m] M.DR <--- TOS; then pop TOS 6
32-bit Real D9 [mod 011 r/m] M.SR <--- TOS; then pop TOS 1/4
FBSTP Store BCD Data, Pop DF [mod 110 r/m] M.BCD <--- TOS; then pop TOS 82
FIST Store Integer FPU Register
32-bit Integer DB [mod 010 r/m] M.SI <--- TOS 4
16-bit Integer DF [mod 010 r/m] M.WI <--- TOS 3
FISTP Store Integer FPU Register, Pop
64-bit Integer DF [mod 111 r/m] M.LI <--- TOS; then pop TOS 6
32-bit Integer DB [mod 011 r/m] M.SI <--- TOS; then pop TOS 4
16-bit Integer DF [mod 011 r/m] M.WI <--- TOS; then pop TOS 3
FSTCW Store FPU Mode Control Register (9B)D9 [mod 111 r/m] Wait Memory <--- Control Mode Register 1 2
FNSTCW Store FPU Mode Control Register D9 [mod 111 r/m] Memory <--- Control Mode Register 1 2
FSTENV Store FPU Environment (9B)D9 [mod 110 r/m] Wait Memory <--- Env. Registers 1 2
FNSTENV Store FPU Environment D9 [mod 110 r/m] Memory <--- Env. Registers 1 2
FSTSW Store FPU Status Register (9B)DD [mod 111 r/m] Wait Memory <--- Status Register 1 2
FNSTSW Store FPU Status Register DD [mod 111 r/m] Memory <--- Status Register 1 2
FSTSW AX Store FPU Status Register to AX (9B)DF E0 Wait AX <--- Status Register 1 2
FNSTSW AX Store FPU Status Register to AX DF E0 AX <--- Status Register 1 2
FSUB Floating Point Subtract
Top of Stack DC [1110 1 n] ST(n) <--- ST(n) - TOS 1/6
80-bit Register D8 [1110 0 n] TOS <--- TOS - ST(n 1/6
64-bit Real DC [mod 100 r/m] TOS <--- TOS - M.DR 1/6
32-bit Real D8 [mod 100 r/m] TOS <--- TOS - M.SR 1/6
FSUBP Floating Point Subtract, Pop DE [1110 1 n] ST(n) <--- ST(n) - TOS; then pop TOS 1/6
FSUBR Floating Point Subtract Reverse
Top of Stack DC [1110 0 n] TOS <--- ST(n) - TOS 1/6
80-bit Register D8 [1110 1 n] ST(n) <--- TOS - ST(n) 1/6
64-bit Real DC [mod 101 r/m] TOS <--- M.DR - TOS 1/6
32-bit Real D8 [mod 101 r/m] TOS <--- M.SR - TOS 1/6
FSUBRP Floating Point Subtract Reverse, Pop DE [1110 0 n] ST(n) <--- TOS - ST(n); then pop TOS 1/6
Table 8-29. FPU Instruction Set (Continued)
FPU Instruction Opcode Operation
Clock Ct
Single/Dbl
(or extended) Notes