Intel ITANIUM ARCHITECTURE - SOFTWARE DEVELOPERS MANUAL VOLUME 1 REV 2.3 Manual page 1681

SUB—Integer Subtraction
Opcode
2C ib
2D iw
2D id
80 /5 ib
81 /5 iw
81 /5 id
83 /5 ib
83 /5 ib
28 / r
29 / r
29 / r
2A / r
2B / r
2B / r
Description
Subtracts the second operand (source operand) from the first operand (destination
operand) and stores the result in the destination operand. The destination operand can
be a register or a memory location; the source operand can be an immediate, register,
or memory location. When an immediate value is used as an operand, it is
sign-extended to the length of the destination operand format.
The SUB instruction does not distinguish between signed or unsigned operands.
Instead, the processor evaluates the result for both data types and sets the OF and CF
flags to indicate a borrow in the signed or unsigned result, respectively. The SF flag
indicates the sign of the signed result.
Operation
DEST  DEST - SRC;
Flags Affected
The OF, SF, ZF, AF, PF, and CF flags are set according to the result.
Additional Itanium System Environment Exceptions
Itanium Reg Faults NaT Register Consumption Abort.
Itanium Mem FaultsVHPT Data Fault, Nested TLB Fault, Data TLB Fault, Alternate Data
Volume 4: Base IA-32 Instruction Reference
Instruction Description
SUB AL, imm8 Subtract imm8 from AL
SUB AX, imm16 Subtract imm16 from AX
SUB EAX, imm32 Subtract imm32 from EAX
SUB r/m8,imm8 Subtract imm8 from r/m8
SUB r/m16,imm16 Subtract imm16 from r/m16
SUB r/m32,imm32 Subtract imm32 from r/m32
SUB r/m16,imm8 Subtract sign-extended imm8 from r/m16
SUB r/m32,imm8 Subtract sign-extended imm8 from r/m32
SUB r/m8,r8 Subtract r8 from r/m8
SUB r/m16,r16 Subtract r16 from r/m16
SUB r/m32,r32 Subtract r32 from r/m32
SUB r8,r/m8 Subtract r/m8 from r8
SUB r16,r/m16 Subtract r/m16 from r16
SUB r32,r/m32 Subtract r/m32 from r32
TLB Fault, Data Page Not Present Fault, Data NaT Page Consumption
Abort, Data Key Miss Fault, Data Key Permission Fault, Data Access
Rights Fault, Data Access Bit Fault, Data Dirty Bit Fault
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