B.ASSEMBLE

assembly

[
  "B.ASSEMBLE INIT, LAST, RegSrc, uimm11, ParentSizeCode"
]

block

[]

catalog_indices

[
  75
]

catalog_records

[
  {
    "asm": "B.ASSEMBLE INIT, LAST, RegSrc, uimm11, ParentSizeCode",
    "constraints": [
      {
        "field": "INIT",
        "operator": "one-of",
        "values": [
          0,
          1
        ]
      },
      {
        "field": "RegSrc",
        "operator": "one-of",
        "values": [
          0,
          1,
          2,
          3,
          4,
          5,
          6,
          7,
          8,
          9,
          10,
          11,
          12,
          13,
          14,
          15,
          16,
          17,
          18,
          19,
          20,
          21,
          22,
          23
        ]
      },
      {
        "field": "ParentSizeCode",
        "operator": "one-of",
        "values": [
          0,
          1,
          2,
          3,
          4,
          5,
          6,
          7,
          8,
          9,
          10,
          11,
          12
        ]
      }
    ],
    "encoding": [
      {
        "index": 0,
        "mask": "0x0000707f",
        "match": "0x00001053",
        "width_bits": 32
      }
    ],
    "encoding_kind": "L32",
    "fields": [
      {
        "name": "INIT",
        "pieces": [
          {
            "instruction_lsb": 31,
            "value_lsb": 0,
            "width": 1
          }
        ],
        "signedness": "encoding-defined",
        "width": 1
      },
      {
        "name": "uimm11",
        "pieces": [
          {
            "instruction_lsb": 20,
            "value_lsb": 0,
            "width": 11
          }
        ],
        "signedness": "unsigned",
        "width": 11
      },
      {
        "name": "RegSrc",
        "pieces": [
          {
            "instruction_lsb": 15,
            "value_lsb": 0,
            "width": 5
          }
        ],
        "signedness": "encoding-defined",
        "width": 5
      },
      {
        "name": "LAST",
        "pieces": [
          {
            "instruction_lsb": 11,
            "value_lsb": 0,
            "width": 1
          }
        ],
        "signedness": "encoding-defined",
        "width": 1
      },
      {
        "name": "ParentSizeCode",
        "pieces": [
          {
            "instruction_lsb": 7,
            "value_lsb": 0,
            "width": 4
          }
        ],
        "signedness": "encoding-defined",
        "width": 4
      }
    ],
    "form_id": "b_assemble_32_122000000002",
    "length_bits": 32,
    "mnemonic": "B.ASSEMBLE",
    "semantic_family": "CMD",
    "semantic_group": "Bundle Range Modifier",
    "semantic_handler": "ApplyBundleAssemble",
    "semantic_summary": "Decodes one destination-range assemble modifier and retains its XLEN-wrapped derived offset in the immediately preceding binder group.",
    "status": "accepted"
  }
]

classification

[
  "operands"
]

contract

{
  "block_composition": [
    "Immediately follows B.IOT or B.IOS and is contiguous with the associated modifier group."
  ],
  "canonical_assembly": [
    "B.ASSEMBLE INIT, LAST, RegSrc, uimm11, ParentSizeCode"
  ],
  "defaults": [
    "uimm11 is unsigned and zero-extended. RegSrc zero names the architectural zero GPR. INIT=0 encodes MIDDLE/LAST; INIT=1 encodes INIT/INIT_LAST."
  ],
  "encoding_class": "standalone-encoded",
  "examples": [
    "B.IOT T0, mask=1111, ->T1<1>; B.ASSEMBLE 1, 1, a0, 0, 10"
  ],
  "exceptions": [
    "Reserved funct3/opcode, RegSrc24..31, and ParentSizeCode13..15 raise Fault_IllegalInstruction before GPR reads, carrier updates, or TPC advance.",
    "INIT=1 with ParentSizeCode=0 or INIT=0 with a nonzero ParentSizeCode raises Fault_BundleControl.",
    "Missing, reversed, duplicate, intervening, or role-incompatible groups raise Fault_BundleControl."
  ],
  "field_contracts": {},
  "field_zero_meanings": {
    "INIT": "Zero selects MIDDLE/LAST rather than INIT/INIT_LAST.",
    "LAST": "One closes the modifier sequence at the semantic assembler.",
    "uimm11": "Zero is a real zero displacement.",
    "RegSrc": "Zero names the architectural zero GPR.",
    "ParentSizeCode": "Zero is the MIDDLE/LAST-only no-parent-size encoding."
  },
  "legality": [
    "RegSrc accepts only absolute GPR selectors 0..23.",
    "ParentSizeCode raw values 0..12 are decoded; INIT/size combinations select INIT, MIDDLE, LAST, or INIT_LAST and contradictory combinations are BundleControl.",
    "Local and Shared parent sizes 1..12 are accepted.",
    "The modifier is legal only in the contiguous immediately preceding binder group and follows source roles."
  ],
  "memory_effects": [
    "none"
  ],
  "operands": [
    {
      "field": "INIT",
      "role": "selects INIT versus MIDDLE/LAST form"
    },
    {
      "field": "LAST",
      "role": "marks the final assembler carrier"
    },
    {
      "field": "RegSrc",
      "role": "absolute GPR selector"
    },
    {
      "field": "uimm11",
      "role": "unsigned XLEN addend"
    },
    {
      "field": "ParentSizeCode",
      "role": "raw parent size code"
    }
  ],
  "ordering": [
    "Decode fixed/reserved fields and raw ranges before any GPR read; compute GPR[RegSrc]+ZeroExtend(uimm11) modulo 2^XLEN after group legality."
  ],
  "state_effects": [
    "Store raw INIT/LAST/RegSrc/uimm11/ParentSizeCode and the derived XLEN offset in the destination carrier of the open binder group.",
    "PEMode=000 on the binder opens a discarded syntactic group; every raw-legal contiguous modifier advances TPC without reads, state, role, or fault effects."
  ],
  "standalone_opcode": true
}

depends_on

[
  "PTO-BLOCK-B-IOT",
  "PTO-BLOCK-B-IOS",
  "PTO-BLOCK-MODEL-OPERANDS-RANGE-MODIFIERS"
]

id

PTO-BLOCK-B-ASSEMBLE

mnemonic

B.ASSEMBLE

summary

Decodes one destination-range assemble modifier and retains its XLEN-wrapped derived offset in the immediately preceding binder group.

surface

block

{
  "classification": [
    "operands"
  ],
  "documentation": "docs/block/operands/B.ASSEMBLE.md",
  "id": "PTO-BLOCK-B-ASSEMBLE",
  "instruction_contract": {
    "artifact": "spec/evidence/instruction-contract-closure.json",
    "mnemonic": "B.ASSEMBLE",
    "ndf_clause": "PTO-INST-BLOCK-B-ASSEMBLE"
  },
  "mnemonic": "B.ASSEMBLE",
  "readiness_subjects": [
    "ADR-0098",
    "ADR-0099"
  ],
  "semantic_tests": [
    "PTO-AVS-BLOCK-B-ASSEMBLE-ENCODING-001"
  ],
  "source": "asl/block/operands/B.ASSEMBLE.asl",
  "surface": "block",
  "tests": [
    "PTO-AVS-BLOCK-B-ASSEMBLE-DECODE-001",
    "PTO-AVS-BLOCK-B-ASSEMBLE-ENCODING-001"
  ]
}