- Synopsis
-
Load indexed byte.
- Mnemonic
-
th.lrb rd, rs1, rs2, imm2
- Encoding
{reg:[ { bits: 7, name: 0xb, attr: ['custom-0, 32 bit'] }, { bits: 5, name: 'rd' }, { bits: 3, name: 0x4, attr: ['Mem-Load'] }, { bits: 5, name: 'rs1' }, { bits: 5, name: 'rs2' }, { bits: 2, name: 'imm2' }, { bits: 5, name: 0x00 }, ]}
- Description
-
This instruction loads a sign extended 8-bit value into the GP register rd from the address rs1 + (rs2 << imm2).
- Operation
addr := rs1 + (rs2 << imm2)
rd := sign_extend(mem[addr])
- Permission
-
This instruction can be executed in all privilege levels.
- Exceptions
-
This instruction triggers the same exceptions that a corresponding
LB
instruction would trigger. - Included in
Extension |
---|
XTheadMemIdx ([xtheadmemidx]) |