Intel 80C186XL, User Manual

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11-5
MATH COPROCESSING
11.3.1.3 Comparison Instructions
Each comparison instruction (see Table 11-3) analyzes the stack top element, often in relationship
to another operand. Then it reports the result in the Status Word condition code. The basic oper-
ations are compare, test (compare with zero) and examine (report tag, sign and normalization).
11.3.1.4 Transcendental Instructions
Transcendental instructions (see Table 11-4) perform the core calculations for common trigono-
metric, hyperbolic, inverse hyperbolic, logarithmic and exponential functions. Use prologue code
to reduce arguments to a range accepted by the instruction. Use epilogue code to adjust the result
to the range of the original arguments. The transcendentals operate on the top one or two stack
elements and return their results to the stack.
Table 11-3. 80C187 Comparison Instructions
FCOM Compare real
FCOMP Compare real and pop
FCOMPP Compare real and pop twice
FICOM Integer compare
FICOMP Integer compare and pop
FTST Test
FXAM Examine
FUCOM Unordered compare
FUCOMP Unordered compare and pop
FUCOMPP Unordered compare and pop twice
Table 11-4. 80C187 Transcendental Instructions
FPTAN Partial tangent
FPATAN Partial arctangent
F2XM1 2
X
– 1
FYL2X Y log
2
X
FYL2XP1 Y log
2
(X+1)
FCOS Cosine
FSIN Sine
FSINCOS Sine and Cosine