RISC-V ISA Explorer · Single-Letter Extensions

M: Integer Multiply/Divide

Ratified 2019-12 · version 2.0.0

Integer multiply and divide instructions, kept out of the base so minimal cores can leave them out.

Typical use: Hardware multiplication and division

Open M in the explorer

Dependencies

Requires

Zmmul

Instructions (13)

Mnemonic	Name	Encoding	Match	Mask
`DIV`	Signed division	`0000001----------100-----0110011`	`0x2004033`	`0xfe00707f`
`DIVU`	Unsigned division	`0000001----------101-----0110011`	`0x2005033`	`0xfe00707f`
`DIVUW`	Unsigned 32-bit division	`0000001----------101-----0111011`	`0x200503b`	`0xfe00707f`
`DIVW`	Signed 32-bit division	`0000001----------100-----0111011`	`0x200403b`	`0xfe00707f`
`MUL`	Signed multiply	`0000001----------000-----0110011`	`0x2000033`	`0xfe00707f`
`MULH`	Signed multiply high	`0000001----------001-----0110011`	`0x2001033`	`0xfe00707f`
`MULHSU`	Signed/unsigned multiply high	`0000001----------010-----0110011`	`0x2002033`	`0xfe00707f`
`MULHU`	Unsigned multiply high	`0000001----------011-----0110011`	`0x2003033`	`0xfe00707f`
`MULW`	Signed 32-bit multiply	`0000001----------000-----0111011`	`0x200003b`	`0xfe00707f`
`REM`	Signed remainder	`0000001----------110-----0110011`	`0x2006033`	`0xfe00707f`
`REMU`	Unsigned remainder	`0000001----------111-----0110011`	`0x2007033`	`0xfe00707f`
`REMUW`	Unsigned 32-bit remainder	`0000001----------111-----0111011`	`0x200703b`	`0xfe00707f`
`REMW`	Signed 32-bit remainder	`0000001----------110-----0111011`	`0x200603b`	`0xfe00707f`