LUI

assembly

[
  "lui simm, ->{t, u, Rd}"
]

block

[]

catalog_indices

[
  339
]

catalog_records

[
  {
    "asm": "lui simm, ->{t, u, Rd}",
    "constraints": [],
    "encoding": [
      {
        "index": 0,
        "mask": "0x0000007f",
        "match": "0x00000017",
        "width_bits": 32
      }
    ],
    "encoding_kind": "L32",
    "fields": [
      {
        "name": "RegDst",
        "pieces": [
          {
            "instruction_lsb": 7,
            "value_lsb": 0,
            "width": 5
          }
        ],
        "signedness": "encoding-defined",
        "width": 5
      },
      {
        "name": "imm20",
        "pieces": [
          {
            "instruction_lsb": 12,
            "value_lsb": 0,
            "width": 20
          }
        ],
        "signedness": "encoding-defined",
        "width": 20
      }
    ],
    "form_id": "lui_32_982113b541d6",
    "length_bits": 32,
    "mnemonic": "LUI",
    "semantic_family": "ALU",
    "semantic_group": "ALU",
    "semantic_handler": "MaterializeLUI",
    "semantic_summary": "LUI sign-extends its encoded 20-bit immediate to XLEN, shifts it left by 12 bits, and publishes the result through RegDst.",
    "status": "accepted"
  }
]

classification

[
  "alu"
]

contract

{
  "block_composition": [
    "none"
  ],
  "canonical_assembly": [
    "lui simm, ->{t, u, Rd}"
  ],
  "defaults": [
    "Every encoded source, immediate, and explicit destination field is required; no field can be omitted.",
    "The mnemonic fixes immediate signedness, selected source width, and implicit-versus-explicit destination behavior."
  ],
  "encoding_class": "standalone-encoded",
  "examples": [
    "lui simm, ->{t, u, rd}"
  ],
  "exceptions": [
    "Materialization is a total fixed-width operation and raises no arithmetic exception.",
    "A fixed-bit mismatch raises Fault_IllegalInstruction before the destination effect and before TPC advances."
  ],
  "field_contracts": {},
  "field_zero_meanings": {
    "RegDst": "Encoded zero discards the result.",
    "imm20": "Encoded zero materializes numeric zero."
  },
  "legality": [
    "RegDst codes 0 and 24..29 discard, codes 1..23 write GPRs, code 30 pushes U, and code 31 pushes T.",
    "Every encoded operand value is assigned; fixed encoding bits must match the canonical form."
  ],
  "memory_effects": [
    "none"
  ],
  "operands": [
    {
      "field": "RegDst",
      "role": "Reg5 destination or discard"
    },
    {
      "field": "imm20",
      "role": "signed upper 20-bit immediate"
    }
  ],
  "ordering": [
    "Snapshot any Reg5 source before the destination effect.",
    "Publish the result, then advance TPC by the encoded instruction length."
  ],
  "standalone_opcode": true,
  "state_effects": [
    "Sign-extend imm20 to XLEN, shift left by 12, and discard overflow beyond XLEN.",
    "Publish the complete XLEN result through the common Reg5 destination map. Relative sources are non-consuming; only a T or U destination push changes a temporary queue.",
    "No memory, reservation, descriptor, numeric-status, block, privilege, branch-target, or other control state changes. Successful execution advances TPC by four bytes."
  ]
}

depends_on

[
  "PTO-BLOCK-MODEL-SCHEMA-PROFILE-ENCODING"
]

id

PTO-SCALAR-LUI

mnemonic

LUI

summary

LUI sign-extends its encoded 20-bit immediate to XLEN, shifts it left by 12 bits, and publishes the result through RegDst.

surface

scalar

{
  "classification": [
    "alu"
  ],
  "documentation": "docs/scalar/alu/LUI.md",
  "id": "PTO-SCALAR-LUI",
  "instruction_contract": {
    "artifact": "spec/evidence/instruction-contract-closure.json",
    "mnemonic": "LUI",
    "ndf_clause": "PTO-INST-SCALAR-LUI"
  },
  "mnemonic": "LUI",
  "readiness_subjects": [
    "ADR-0026",
    "ADR-0059"
  ],
  "semantic_tests": [
    "PTO-AVS-SCALAR-LUI-MATERIALIZE-001"
  ],
  "source": "asl/scalar/alu/LUI.asl",
  "surface": "scalar",
  "tests": [
    "PTO-AVS-SCALAR-LUI-DECODE-001",
    "PTO-AVS-SCALAR-LUI-MATERIALIZE-001"
  ]
}