Operands and parameters
RegDst- Reg5 loaded-value destination or discard
SrcL- Reg5 address-base source
simm22- signed address displacement
HL.LHUI.U snapshots its scalar sources, forms its encoded address, and loads one aligned little-endian 2-byte value.
PTO-SCALAR-HL-LHUI-Uhl.lhui.u [SrcL, simm], ->{t, u, Rd}| Field | Bits | Signedness | Architectural role | Encoded zero |
|---|---|---|---|---|
RegDst | 5 | encoding-defined | Reg5 loaded-value destination or discard | Encoded zero discards this result without suppressing the instruction's other effects. |
SrcL | 5 | encoding-defined | Reg5 address-base source | Encoded zero reads the architectural zero GPR. |
simm22 | 22 | signed | signed address displacement | Encoded zero supplies a zero displacement; it does not denote omission. |
Loading WaveDrom diagram… The encoding table and WaveJSON remain available below.
| Decoded item | Bit range | Value |
|---|---|---|
| simm22 | 47:36 | variable |
| SrcL | 35:31 | variable |
| Constant | 30:28 | 3'b101 |
| RegDst | 27:23 | variable |
| Constant | 22:16 | 7'b0101001 |
| simm22 | 15:6 | variable |
| Constant | 5:0 | 6'b001110 |
{
"reg": [
{
"bits": 6,
"name": "6'b001110"
},
{
"bits": 10,
"name": "simm22"
},
{
"bits": 7,
"name": "7'b0101001"
},
{
"bits": 5,
"name": "RegDst"
},
{
"bits": 3,
"name": "3'b101"
},
{
"bits": 5,
"name": "SrcL"
},
{
"bits": 12,
"name": "simm22"
}
],
"config": {
"bits": 48,
"fontsize": 13,
"hspace": 900,
"lanes": 2,
"offset": 0
}
}hl.lhui.u [SrcL, simm], ->{t, u, Rd}
RegDstSrcLsimm22This Operation comes directly from the instruction owner; the page does not rewrite its behavior.
readonly func InstructionContractOperation_HL_LHUI_U() => ScalarOperationbegin return ScalarOperation_HL_LHUI_U;end;readonly func InstructionContractHandler_HL_LHUI_U() => ScalarSemanticHandlerbegin return ScalarHandler_ExecuteScalarLoad;end;
pure func InstructionContractAGUAction_HL_LHUI_U() => ScalarAGUActionbegin return ScalarAGU_Load;end;
pure func InstructionContractAGUAddressKind_HL_LHUI_U() => ScalarAGUAddressKindbegin return ScalarAGU_Immediate;end;
pure func InstructionContractAGUSizeBytes_HL_LHUI_U() => integer {1,2,4,8}begin return 2;end;
pure func InstructionContractAGUOffsetScale_HL_LHUI_U() => integer {0..3}begin return 0;end;
pure func InstructionContractAGUUpdateMode_HL_LHUI_U() => AddressUpdateModebegin return AddressUpdate_None;end;
pure func InstructionContractAGUSignedLoad_HL_LHUI_U() => booleanbegin return FALSE;end;
pure func InstructionContractAGUPrefetchReturnsAddress_HL_LHUI_U() => booleanbegin return FALSE;end;// PTO-INSTRUCTION: {"assembly":["hl.lhui.u [SrcL, simm], ->{t, u, Rd}"],"block":[],"catalog_indices":[187],"catalog_records":[{"agu":{"action":"Load","address_kind":"Immediate","offset_scale":0,"prefetch_returns_address":false,"signed_load":false,"size_bytes":2,"update_mode":"None"},"asm":"hl.lhui.u [SrcL, simm], ->{t, u, Rd}","constraints":[],"encoding":[{"index":0,"mask":"0x0000707f003f","match":"0x00005029000e","width_bits":48}],"encoding_kind":"HL48","fields":[{"name":"RegDst","pieces":[{"instruction_lsb":23,"value_lsb":0,"width":5}],"signedness":"encoding-defined","width":5},{"name":"SrcL","pieces":[{"instruction_lsb":31,"value_lsb":0,"width":5}],"signedness":"encoding-defined","width":5},{"name":"simm22","pieces":[{"instruction_lsb":36,"value_lsb":0,"width":12},{"instruction_lsb":6,"value_lsb":12,"width":10}],"signedness":"signed","width":22}],"form_id":"hl_lhui_u_48_d75649bac1c7","length_bits":48,"mnemonic":"HL.LHUI.U","semantic_family":"AGU","semantic_group":"LDA/LONG","semantic_handler":"ExecuteScalarLoad","semantic_summary":"HL.LHUI.U snapshots its scalar sources, forms its encoded address, and loads one aligned little-endian 2-byte value.","status":"accepted"}],"classification":["agu"],"contract":{"block_composition":["none"],"canonical_assembly":["hl.lhui.u [SrcL, simm], ->{t, u, Rd}"],"defaults":["Every displayed operand field is encoded explicitly; encoded zero is a value and never denotes omission."],"encoding_class":"standalone-encoded","examples":["hl.lhui.u [SrcL, simm], ->{t, u, Rd}"],"exceptions":["A fixed-bit mismatch, reserved field value, or unavailable selected T/U source raises Fault_IllegalInstruction before instruction effects.","A misaligned 2-byte address raises Fault_DataAlignment before translation or permission. A later permission or bounded-memory failure raises Fault_DataPage at the original address.","A fault emits no successful memory event, performs no partial memory or destination effect, preserves pending writeback, and leaves TPC at the faulting instruction.","Recovery performs a full reissue: every address, source snapshot, preflight, memory operation, and destination is recomputed with no retained progress."],"field_contracts":{},"field_zero_meanings":{"RegDst":"Encoded zero discards this result without suppressing the instruction's other effects.","SrcL":"Encoded zero reads the architectural zero GPR.","simm22":"Encoded zero supplies a zero displacement; it does not denote omission."},"legality":["Every encoded Reg5 source uses the complete domain: codes 0..23 select absolute GPRs, codes 24..27 select T#1..T#4, and codes 28..31 select U#1..U#4 without consumption.","Every Reg5 destination is assigned: codes 1..23 write GPRs, code 30 pushes U, code 31 pushes T, and codes 0 and 24..29 discard only that result.","simm22 assigns every signed 22-bit value -2097152..2097151; the encoded byte displacement is that value multiplied by 1.","Each memory address must be aligned to the 2-byte access size; a 2-byte access is the complete transfer unit."],"memory_effects":["After complete preflight, perform one little-endian 2-byte load and record one relaxed load event.","The load preserves memory and reservation state."],"operands":[{"field":"RegDst","role":"Reg5 loaded-value destination or discard"},{"field":"SrcL","role":"Reg5 address-base source"},{"field":"simm22","role":"signed address displacement"}],"ordering":["Snapshot all explicit and implicit scalar sources before destination or memory effects; duplicate and source/destination aliases observe pre-instruction values.","Complete the relaxed 2-byte memory operation, publish any result or writeback, and then advance TPC."],"standalone_opcode":true,"state_effects":["Sign-extend simm22, multiply it by 1, and add it modulo 2^PTO_XLEN to the SrcL base.","After a successful 2-byte load, zero-extend the loaded value to PTO_XLEN and publish it through the destination.","Successful execution advances TPC by 6 bytes; a rejected or faulting attempt does not retire."]},"depends_on":["PTO-BLOCK-MODEL-SCHEMA-PROFILE-ENCODING"],"id":"PTO-SCALAR-HL-LHUI-U","mnemonic":"HL.LHUI.U","summary":"HL.LHUI.U snapshots its scalar sources, forms its encoded address, and loads one aligned little-endian 2-byte value.","surface":"scalar"}// PTO-REVIEW: {"review_method":"formal-definition-read","outcome":"FORMAL-COMPLETE","reviewed_fields":["assembly","encoding","defaults","operation","state","memory","ordering","faults","reserved"]}// DOC-BEGIN: decodereadonly func InstructionContractOperation_HL_LHUI_U() => ScalarOperationbegin return ScalarOperation_HL_LHUI_U;end;// DOC-END: decode// DOC-BEGIN: operationreadonly func InstructionContractHandler_HL_LHUI_U() => ScalarSemanticHandlerbegin return ScalarHandler_ExecuteScalarLoad;end;
pure func InstructionContractAGUAction_HL_LHUI_U() => ScalarAGUActionbegin return ScalarAGU_Load;end;
pure func InstructionContractAGUAddressKind_HL_LHUI_U() => ScalarAGUAddressKindbegin return ScalarAGU_Immediate;end;
pure func InstructionContractAGUSizeBytes_HL_LHUI_U() => integer {1,2,4,8}begin return 2;end;
pure func InstructionContractAGUOffsetScale_HL_LHUI_U() => integer {0..3}begin return 0;end;
pure func InstructionContractAGUUpdateMode_HL_LHUI_U() => AddressUpdateModebegin return AddressUpdate_None;end;
pure func InstructionContractAGUSignedLoad_HL_LHUI_U() => booleanbegin return FALSE;end;
pure func InstructionContractAGUPrefetchReturnsAddress_HL_LHUI_U() => booleanbegin return FALSE;end;// DOC-END: operation
HL.LHUI.U is a standalone 48-bit scalar AGU instruction that loads one 2-byte little-endian value and zero-extends the transferred bits when the result is narrower than PTO_XLEN using Immediate addressing.
The address path sign-extends simm22, scales it by 1, and adds the displacement to the snapshotted SrcL value modulo 2^PTO_XLEN.
After complete preflight, one aligned little-endian 2-byte load is performed. Its result is zero-extended before destination publication.
This form does not publish an address-base writeback.
RegDst is a 5-bit field selecting the loaded-value result.SrcL is a 5-bit field selecting the address base.simm22 is a 22-bit field selecting the signed displacement before the 1 scale factor.All explicit and implicit scalar sources are snapshotted before any memory or destination effect, so aliases use pre-instruction values.
Successful execution records one relaxed load event; memory and reservation state are preserved.
After all result or writeback publication, HL.LHUI.U advances TPC by 6 bytes; a rejected or faulting attempt does not retire.
Each accessed address is aligned to the 2-byte transfer unit. Misalignment selects Fault_DataAlignment before translation; a later permission or bounded-memory failure selects Fault_DataPage at the original address.
A fixed-bit mismatch, reserved field value, or unavailable selected T/U source selects Fault_IllegalInstruction before instruction effects.
A fault records no successful memory event and commits no partial memory, result, or writeback effect. Re-execution recomputes the source snapshots, address, preflight, transfer, and publication from the beginning.
This walkthrough explains how to use the page and does not add instruction behavior.
hl.lhui.u [SrcL, simm], ->{t, u, Rd} and identify the encoded address fields.Bodies come from owning ASL. Dragging or buttons change only this page-session view order.
No NDF clause is attached to this unit.
12 matching entries
PTO-AVS-AGU-HL-LHUI-U-ALIAS-001tests/asl/scalar/agu/HL.LHUI.U/scalar-exec-hl-lhui-u-registers-001.asl91013d00eaabccbfa3b268be0baec9da8dc30c5821a57b736bd9d7e1b4516af7PTO-AVS-AGU-HL-LHUI-U-BOUND-001tests/asl/scalar/agu/HL.LHUI.U/scalar-bound-hl-lhui-u-address-001.asl3da89b54fc508dccea5bcb993c6c51f6eaa749a811186f2a0d1b523e8b300dccPTO-AVS-AGU-HL-LHUI-U-EXEC-001tests/asl/scalar/agu/HL.LHUI.U/scalar-exec-hl-lhui-u-direct-001.aslabbc90fccbed2a13c06db542b5b4e2b3303d4fd8bec6222fd04292b65a2be428PTO-AVS-AGU-HL-LHUI-U-FAULT-001tests/asl/scalar/agu/HL.LHUI.U/scalar-fault-hl-lhui-u-precise-001.asl8aab8662bb0c005c29b03617beffe254635f15457a2739e736f4a178238521fbPTO-AVS-SCALAR-HL-LHUI-U-DECODE-001tests/asl/scalar/agu/HL.LHUI.U/scalar-decode-hl-lhui-u-canonical-001.asl61253070980575182ab5a11f206b65fcdc33c6238ee8e21177f4502c4f5f6080PTO-EVIDENCE-RELEASE-TRACEABILITYPTO-EVIDENCE-RELEASE-TRACEABILITYspec/evidence/release-traceability-readiness.jsonc7327021d39dc67ac5564bc55073b3870a397d79ac8d9648284d56e33bc14a3ePTO-EVIDENCE-INSTRUCTION-CONTRACT-CLOSUREPTO-EVIDENCE-INSTRUCTION-CONTRACT-CLOSUREspec/evidence/instruction-contract-closure.json3ef2bb62421c79dff8fa77a1c7983923b523244b8090812883ef81286ca8106aPTO-EVIDENCE-ARCHITECTURE-READINESSPTO-EVIDENCE-ARCHITECTURE-READINESSspec/evidence/architecture-readiness.json4b0b85199101251bea744e0f3591cc31906909dc80d5ab651c417a936036a004PTO-EVIDENCE-RELEASE-GATE-READINESSPTO-EVIDENCE-RELEASE-GATE-READINESSspec/evidence/release-gate-readiness.jsona0f4d2b6920c08981ea55fd8ef820708a40d4feb5402c5150e8e9ab532d84ce0PTO-EVIDENCE-RELEASE-MANIFESTPTO-EVIDENCE-RELEASE-MANIFESTspec/release-manifest.json1a64c109ed7a90351c41e2a418b3c0ebaf8ad975838986d2101385186b85c0d8Loading ADR-0029…
ADR-0029docs/status/decisions/0029-scalar-agu-totality-and-restart.md778e7bc53a5ae6487c051d66d0f84b6d697d6302628716bf5c745166ce982eefLoading ADR-0059…
ADR-0059docs/status/decisions/0059-mnemonic-field-encoding-closure.mdf18d13f735cfaf9f2803c754c5818f4af33d1cc42c489f0d9ce060b07bb3a196{
"classification": [
"agu"
],
"documentation": "docs/scalar/agu/HL.LHUI.U.md",
"id": "PTO-SCALAR-HL-LHUI-U",
"instruction_contract": {
"artifact": "spec/evidence/instruction-contract-closure.json",
"mnemonic": "HL.LHUI.U",
"ndf_clause": "PTO-INST-SCALAR-HL-LHUI-U"
},
"mnemonic": "HL.LHUI.U",
"readiness_subjects": [
"ADR-0029",
"ADR-0059"
],
"semantic_tests": [
"PTO-AVS-AGU-HL-LHUI-U-ALIAS-001",
"PTO-AVS-AGU-HL-LHUI-U-BOUND-001",
"PTO-AVS-AGU-HL-LHUI-U-EXEC-001",
"PTO-AVS-AGU-HL-LHUI-U-FAULT-001"
],
"source": "asl/scalar/agu/HL.LHUI.U.asl",
"surface": "scalar",
"tests": [
"PTO-AVS-AGU-HL-LHUI-U-ALIAS-001",
"PTO-AVS-AGU-HL-LHUI-U-BOUND-001",
"PTO-AVS-AGU-HL-LHUI-U-EXEC-001",
"PTO-AVS-AGU-HL-LHUI-U-FAULT-001",
"PTO-AVS-SCALAR-HL-LHUI-U-DECODE-001"
]
}0.58.5 · Release candidate7dc8b7e5b121d2b2499a2273bebff29e2cd86812aaca9957b06f5b29e15066f263ee89baa337902f63684e2bba11b916d071effa482c8a50d0f7eedfdb8c777fff60476ca811af8021b22940a74d8658162b1b3aasl/scalar/agu/HL.LHUI.U.aslasl/scalar/agu/HL.LHUI.U.asl