A-19
OPCODE MAP
Table A-16. DC Opcode Map When ModR/M Byte is Outside 00H to BFH
4
NOTE:
1.All blanks in the opcode map are reserved and should not be used. Do not depend on the operation of
these undefined opcodes.
A.2.6.8.ESCAPE OPCODES WITH DD AS FIRST BYTE
Table A-17 and A-18 contain the opcodes maps for the escape instruction opcodes that begin
with DDH. Table A-17 shows the opcode map if the accompanying ModR/M byte within the
range of 00H through BFH. Here, the value of bits 5, 4, and 3 (the nnn field in Figure A-1) se-
lects the instruction.
0
1
2
3
4
5
7
C
FADD
ST(0),ST(0)ST(1),ST(0)ST(2),ST(0)ST(3),ST(0)ST(4),ST(0)ST(5),ST(0)ST(6),ST(0)ST(7),ST(0)
D
E
FSUBR
ST(0),ST(0)ST(1),ST(0)ST(2),ST(0)ST(3),ST(0)ST(4),ST(0)ST(5),ST(0)ST(6),ST(0)ST(7),ST(0)
F
FDIVR
ST(0),ST(0)ST(1),ST(0)ST(2),ST(0)ST(3),ST(0)ST(4),ST(0)ST(5),ST(0)ST(6),ST(0)ST(7),ST(0)
8
9
A
B
C
D
E
F
C
FMUL
ST(0),ST(0)ST(1),ST(0)ST(2),ST(0)ST(3),ST(0)ST(4),ST(0)ST(5),ST(0)ST(6),ST(0)ST(7),ST(0)
D
E
FSUB
ST(0),ST(0)ST(1),ST(0)ST(2),ST(0)ST(3),ST(0)ST(4),ST(0)ST(5),ST(0)ST(6),ST(0)ST(7),ST(0)
F
FDIV
ST(0),ST(0)ST(1),ST(0)ST(2),ST(0)ST(3),ST(0)ST(4),ST(0)ST(5),ST(0)ST(6),ST(0)ST(7),ST(0)
