Intel ITANIUM ARCHITECTURE - SOFTWARE DEVELOPERS MANUAL VOLUME 1 REV 2.3 Manual page 1325

AAM—ASCII Adjust AX After Multiply
Opcode
D4 0A
Description
Adjusts the result of the multiplication of two unpacked BCD values to create a pair of
unpacked BCD values. The AX register is the implied source and destination operand for
this instruction. The AAM instruction is only useful when it follows an MUL instruction
that multiplies (binary multiplication) two unpacked BCD values and stores a word
result in the AX register. The AAM instruction then adjusts the contents of the AX
register to contain the correct 2-digit unpacked BCD result.
Operation
tempAL  AL;
AH  tempAL / imm8;
AL  tempAL MOD imm8;
The immediate value (imm8) is taken from the second byte of the instruction, which
under normal assembly is 0AH (10 decimal). However, this immediate value can be
changed to produce a different result.
Flags Affected
The SF, ZF, and PF flags are set according to the result. The OF, AF, and CF flags are
undefined.
Additional Itanium System Environment Exceptions
Itanium Reg Faults NaT Register Consumption Abort.
Exceptions (All Operating Modes)
None.
Volume 4: Base IA-32 Instruction Reference
Instruction
AAM
Description
ASCII adjust AX after multiply
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