FIDIVR
Usage: FIDIVR dest,src Modifies flags:
Divides the 'src' operand by the 'dest' operand and stores the result in the 'dest' location. The 'dest' operand (divisor) is always in an FPU register; the 'src' operand (dividend) can be a register or a memory location. .
Floating-Point/Integer Division
FIDIV mem16 ; DE /6 [8086,FPU]
FIDIV mem32 ; DA /6 [8086,FPU]
FIDIVR mem16 ; DE /7 [8086,FPU]
FIDIVR mem32 ; DA /7 [8086,FPU]
FIDIV divides ST0 by the 16-bit or 32-bit integer stored in the given memory location, and stores the result in ST0. FIDIVR does the division the other way up: it divides the integer by ST0, but still stores the result in ST0.
Source operands in memory can be in single-precision or double-precision floating-point format, word or doubleword integer format.
The C0, C1, C2, and C3 are undefined.
FDIVR/FDIVRP/FIDIVR-Reverse Divide
Opcode Instruction Description
D8 /7 FDIVR m32fp Divide m32fp by ST(0) and store result in ST(0)
DC /7 FDIVR m64fp Divide m64fp by ST(0) and store result in ST(0)
D8 F8 +i FDIVR ST(0), ST(i) Divide ST(i) by ST(0) and store result in ST(0)
DC F0 +i FDIVR ST(i), ST(0) Divide ST(0) by ST(i) and store result in ST(i)
DE F0 +i FDIVRP ST(i), ST(0) Divide ST(0) by ST(i), store result in ST(i), and pop the register stack
DE F1 FDIVRP Divide ST(0) by ST(1), store result in ST(1), and pop the register stack
DA /7 FIDIVR m32int Divide m32int by ST(0) and store result in ST(0)
DE /7 FIDIVR m16int Divide m16int by ST(0) and store result in ST(0)
EXAMPLE:
FIDIVR ST5 ST0