Operands and parameters
SrcL- Reg5 address-base source
simm5- signed address displacement
C.LDI snapshots its scalar sources, forms its encoded address, and loads one aligned little-endian 8-byte value.
PTO-SCALAR-C-LDIc.ldi [srcL, simm], ->t| Field | Bits | Signedness | Architectural role | Encoded zero |
|---|---|---|---|---|
SrcL | 5 | encoding-defined | Reg5 address-base source | Encoded zero reads the architectural zero GPR. |
simm5 | 5 | 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 |
|---|---|---|
| simm5 | 15:11 | variable |
| SrcL | 10:6 | variable |
| Constant | 5:0 | 6'b011010 |
{
"reg": [
{
"bits": 6,
"name": "6'b011010"
},
{
"bits": 5,
"name": "SrcL"
},
{
"bits": 5,
"name": "simm5"
}
],
"config": {
"bits": 16,
"fontsize": 13,
"hspace": 640,
"lanes": 1,
"offset": 0
}
}c.ldi [srcL, simm], ->t
SrcLsimm5This Operation comes directly from the instruction owner; the page does not rewrite its behavior.
readonly func InstructionContractOperation_C_LDI() => ScalarOperationbegin return ScalarOperation_C_LDI;end;readonly func InstructionContractHandler_C_LDI() => ScalarSemanticHandlerbegin return ScalarHandler_ExecuteScalarLoad;end;
pure func InstructionContractAGUAction_C_LDI() => ScalarAGUActionbegin return ScalarAGU_Load;end;
pure func InstructionContractAGUAddressKind_C_LDI() => ScalarAGUAddressKindbegin return ScalarAGU_Compressed;end;
pure func InstructionContractAGUSizeBytes_C_LDI() => integer {1,2,4,8}begin return 8;end;
pure func InstructionContractAGUOffsetScale_C_LDI() => integer {0..3}begin return 3;end;
pure func InstructionContractAGUUpdateMode_C_LDI() => AddressUpdateModebegin return AddressUpdate_None;end;
pure func InstructionContractAGUSignedLoad_C_LDI() => booleanbegin return FALSE;end;
pure func InstructionContractAGUPrefetchReturnsAddress_C_LDI() => booleanbegin return FALSE;end;// PTO-INSTRUCTION: {"assembly":["c.ldi [srcL, simm], ->t"],"block":[],"catalog_indices":[29],"catalog_records":[{"agu":{"action":"Load","address_kind":"Compressed","offset_scale":3,"prefetch_returns_address":false,"signed_load":false,"size_bytes":8,"update_mode":"None"},"asm":"c.ldi [srcL, simm], ->t","constraints":[],"encoding":[{"index":0,"mask":"0x003f","match":"0x001a","width_bits":16}],"encoding_kind":"C16","fields":[{"name":"SrcL","pieces":[{"instruction_lsb":6,"value_lsb":0,"width":5}],"signedness":"encoding-defined","width":5},{"name":"simm5","pieces":[{"instruction_lsb":11,"value_lsb":0,"width":5}],"signedness":"signed","width":5}],"form_id":"c_ldi_16_973f42d37f29","length_bits":16,"mnemonic":"C.LDI","semantic_family":"AGU","semantic_group":"LDA/BASE_IMM","semantic_handler":"ExecuteScalarLoad","semantic_summary":"C.LDI snapshots its scalar sources, forms its encoded address, and loads one aligned little-endian 8-byte value.","status":"accepted"}],"classification":["agu"],"contract":{"block_composition":["none"],"canonical_assembly":["c.ldi [srcL, simm], ->t"],"defaults":["Every displayed operand field is encoded explicitly; encoded zero is a value and never denotes omission."],"encoding_class":"standalone-encoded","examples":["c.ldi [srcL, simm], ->t"],"exceptions":["A fixed-bit mismatch, reserved field value, or unavailable selected T/U source raises Fault_IllegalInstruction before instruction effects.","A misaligned 8-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":{"SrcL":"Encoded zero reads the architectural zero GPR.","simm5":"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.","simm5 assigns every signed 5-bit value -16..15; the encoded byte displacement is that value multiplied by 8.","Each memory address must be aligned to the 8-byte access size; a 8-byte access is the complete transfer unit."],"memory_effects":["After complete preflight, perform one little-endian 8-byte load and record one relaxed load event.","The load preserves memory and reservation state."],"operands":[{"field":"SrcL","role":"Reg5 address-base source"},{"field":"simm5","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 8-byte memory operation, publish any result or writeback, and then advance TPC."],"standalone_opcode":true,"state_effects":["Sign-extend simm5, multiply it by 8, and add it modulo 2^PTO_XLEN to the SrcL base.","After a successful 8-byte load, preserve the complete 64-bit loaded bit pattern and publish it through the destination.","Successful execution advances TPC by 2 bytes; a rejected or faulting attempt does not retire."]},"depends_on":["PTO-BLOCK-MODEL-SCHEMA-PROFILE-ENCODING"],"id":"PTO-SCALAR-C-LDI","mnemonic":"C.LDI","summary":"C.LDI snapshots its scalar sources, forms its encoded address, and loads one aligned little-endian 8-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_C_LDI() => ScalarOperationbegin return ScalarOperation_C_LDI;end;// DOC-END: decode// DOC-BEGIN: operationreadonly func InstructionContractHandler_C_LDI() => ScalarSemanticHandlerbegin return ScalarHandler_ExecuteScalarLoad;end;
pure func InstructionContractAGUAction_C_LDI() => ScalarAGUActionbegin return ScalarAGU_Load;end;
pure func InstructionContractAGUAddressKind_C_LDI() => ScalarAGUAddressKindbegin return ScalarAGU_Compressed;end;
pure func InstructionContractAGUSizeBytes_C_LDI() => integer {1,2,4,8}begin return 8;end;
pure func InstructionContractAGUOffsetScale_C_LDI() => integer {0..3}begin return 3;end;
pure func InstructionContractAGUUpdateMode_C_LDI() => AddressUpdateModebegin return AddressUpdate_None;end;
pure func InstructionContractAGUSignedLoad_C_LDI() => booleanbegin return FALSE;end;
pure func InstructionContractAGUPrefetchReturnsAddress_C_LDI() => booleanbegin return FALSE;end;// DOC-END: operation
C.LDI is a standalone 16-bit scalar AGU instruction that loads one 8-byte little-endian value and zero-extends the transferred bits when the result is narrower than PTO_XLEN using Compressed addressing. The compressed form publishes the loaded result to implicit T#1.
The address path sign-extends simm5, scales it by 8, and adds the displacement to the snapshotted SrcL value modulo 2^PTO_XLEN.
After complete preflight, one aligned little-endian 8-byte load is performed. Its result is kept as the complete 64-bit pattern before destination publication.
This form does not publish an address-base writeback.
SrcL is a 5-bit field selecting the address base.simm5 is a 5-bit field selecting the signed displacement before the 8 scale factor.T#1 is the implicit loaded-value destination.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, C.LDI advances TPC by 2 bytes; a rejected or faulting attempt does not retire.
Each accessed address is aligned to the 8-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.
c.ldi [srcL, simm], ->t 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-C-LDI-ALIAS-001tests/asl/scalar/agu/C.LDI/scalar-exec-c-ldi-registers-001.asla7d1185ece5f67d9991a207feba12503201540fd1400c3b37ba3e2fd0ff37fccPTO-AVS-AGU-C-LDI-BOUND-001tests/asl/scalar/agu/C.LDI/scalar-bound-c-ldi-address-001.asl080f3f8271a349b28bf0122f0146a0145c385f2e544f0a6d089011a90e28a301PTO-AVS-AGU-C-LDI-EXEC-001tests/asl/scalar/agu/C.LDI/scalar-exec-c-ldi-direct-001.aslde82abb99e4a28e832e9c33954da9dea4afbcc04f3db3d760095b1e731d682d0PTO-AVS-AGU-C-LDI-FAULT-001tests/asl/scalar/agu/C.LDI/scalar-fault-c-ldi-precise-001.asle5d18d2e8fd820ec799ab87175a77969e740e73273ebc03bb978e5f1fc866a61PTO-AVS-SCALAR-C-LDI-DECODE-001tests/asl/scalar/agu/C.LDI/scalar-decode-c-ldi-canonical-001.asl04c1418f49224103523b126e058b66c1fe97ff23fa36467d8eb4e443e9a44ebbPTO-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/C.LDI.md",
"id": "PTO-SCALAR-C-LDI",
"instruction_contract": {
"artifact": "spec/evidence/instruction-contract-closure.json",
"mnemonic": "C.LDI",
"ndf_clause": "PTO-INST-SCALAR-C-LDI"
},
"mnemonic": "C.LDI",
"readiness_subjects": [
"ADR-0029",
"ADR-0059"
],
"semantic_tests": [
"PTO-AVS-AGU-C-LDI-ALIAS-001",
"PTO-AVS-AGU-C-LDI-BOUND-001",
"PTO-AVS-AGU-C-LDI-EXEC-001",
"PTO-AVS-AGU-C-LDI-FAULT-001"
],
"source": "asl/scalar/agu/C.LDI.asl",
"surface": "scalar",
"tests": [
"PTO-AVS-AGU-C-LDI-ALIAS-001",
"PTO-AVS-AGU-C-LDI-BOUND-001",
"PTO-AVS-AGU-C-LDI-EXEC-001",
"PTO-AVS-AGU-C-LDI-FAULT-001",
"PTO-AVS-SCALAR-C-LDI-DECODE-001"
]
}0.58.5 · Release candidate7dc8b7e5b121d2b2499a2273bebff29e2cd86812cf9ea86090f7fbf98a32a47f33692aff5ba8b400d32e1224eb4780714dbab1f22cdeb0ecec2fafe0f7cb16a55d894a53c6efc6f1a1287167bba190e87e072855asl/scalar/agu/C.LDI.aslasl/scalar/agu/C.LDI.asl