Intel® Architecture Instruction Set Extensions Programming Reference

OPCODE MAP
Table A-16 shows the map if the ModR/M byte is outside the range of 00H-BFH. In this case the first digit of the ModR/M byte
selects the table row and the second digit selects the column.
Table A-16. DC Opcode Map When ModR/M Byte is Outside 00H to BFH *
0 1 2 3 4 5 6 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)
NOTES:
* All blanks in all opcode maps are reserved and must not be used. Do not depend on the operation of undefined or reserved locations.
A.5.2.6 Escape Opcodes with DD as First Byte
Table A-17 and A-18 contain maps for escape instruction opcodes that begin with DDH. Table A-17 shows the map if the ModR/M
byte is in the range of 00H-BFH. Here, the value of bits 3-5 (the nnn field in Figure A-1) selects the instruction.
Table A-17. DD Opcode Map When ModR/M Byte is Within 00H to BFH *
nnn Field of ModR/M Byte
000B 001B 010B 011B 100B 101B 110B 111B
FLD
FISTTP
FST
FSTP FRSTOR
FSAVE FSTSW
double-real
NOTES:
integer64 double-real double-real 98/108bytes
98/108bytes 2 bytes
* All blanks in all opcode maps are reserved and must not be used. Do not depend on the operation of undefined or reserved locations.
A-26 Ref. # 319433-014