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REMU

RISC-V REMU Instruction Details

Instruction ManualR-type

Unsigned remainder of rs1 / rs2, stored in rd

Instruction Syntax

remu rd, rs1, rs2
Operand Breakdown
Destination rd: register receiving the operation result.
Source rs1: register holding the first operand.
Source rs2: register holding the second operand.
MArithmeticDivision

Instruction Encoding

31..25
funct7
24..20
rs2
19..15
rs1
14..12
funct3
11..7
rd
6..0
opcode

REMU uses opcode 0110011 (0x33), funct3 111, funct7 0000001. The rs1 and rs2 fields select the two source registers, and rd selects the destination register.

Format: R-type
opcode: 0110011 (0x33)
funct3: 111 (0x7)
funct7: 0000001 (0x01)

Instruction Behavior

REMU provides the remainder of unsigned division of rs1 by rs2. On division by zero, the remainder equals the dividend. Unsigned division cannot overflow.

Common Usage Scenarios

Address & Pointer

Understand this scenario with real code like «remu a0, a1, a2 # a0 = a1 % a2 (unsigned)».

Type Conversion

Understand this scenario with real code like «remu a0, a1, a2 # a0 = a1 % a2 (unsigned)».

Pre-Use Checklist

Syntax Check
  • Confirm the current instruction format is R-type.
  • Confirm the operand order matches the example.
Semantic Check
  • Ensure the destination register usage is compatible with the calling convention.
  • Confirm this is not the lower-level form of a pseudo-instruction expansion.

Pitfalls / Common Confusions

Division by zero returns dividend, no trap