Operands and parameters
SrcL- Reg5 store-data source
SrcR- Reg5 address-base source
simm12- signed address displacement
SWI snapshots its scalar sources, forms its encoded address, and stores one aligned little-endian 4-byte value.
PTO-SCALAR-SWIswi SrcL, [SrcR, simm]| Field | Bits | Signedness | Architectural role | Encoded zero |
|---|---|---|---|---|
SrcL | 5 | encoding-defined | Reg5 store-data source | Encoded zero reads the architectural zero GPR. |
SrcR | 5 | encoding-defined | Reg5 address-base source | Encoded zero reads the architectural zero GPR. |
simm12 | 12 | 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 |
|---|---|---|
| simm12 | 31:25 | variable |
| SrcR | 24:20 | variable |
| SrcL | 19:15 | variable |
| Constant | 14:12 | 3'b010 |
| simm12 | 11:7 | variable |
| Constant | 6:0 | 7'b1011001 |
{
"reg": [
{
"bits": 7,
"name": "7'b1011001"
},
{
"bits": 5,
"name": "simm12"
},
{
"bits": 3,
"name": "3'b010"
},
{
"bits": 5,
"name": "SrcL"
},
{
"bits": 5,
"name": "SrcR"
},
{
"bits": 7,
"name": "simm12"
}
],
"config": {
"bits": 32,
"fontsize": 13,
"hspace": 900,
"lanes": 1,
"offset": 0
}
}swi SrcL, [SrcR, simm]
SrcLSrcRsimm12This Operation comes directly from the instruction owner; the page does not rewrite its behavior.
readonly func InstructionContractOperation_SWI() => ScalarOperationbegin return ScalarOperation_SWI;end;readonly func InstructionContractHandler_SWI() => ScalarSemanticHandlerbegin return ScalarHandler_ExecuteScalarStore;end;
pure func InstructionContractAGUAction_SWI() => ScalarAGUActionbegin return ScalarAGU_Store;end;
pure func InstructionContractAGUAddressKind_SWI() => ScalarAGUAddressKindbegin return ScalarAGU_Immediate;end;
pure func InstructionContractAGUSizeBytes_SWI() => integer {1,2,4,8}begin return 4;end;
pure func InstructionContractAGUOffsetScale_SWI() => integer {0..3}begin return 2;end;
pure func InstructionContractAGUUpdateMode_SWI() => AddressUpdateModebegin return AddressUpdate_None;end;
pure func InstructionContractAGUSignedLoad_SWI() => booleanbegin return FALSE;end;
pure func InstructionContractAGUPrefetchReturnsAddress_SWI() => booleanbegin return FALSE;end;// PTO-INSTRUCTION: {"assembly":["swi SrcL, [SrcR, simm]"],"block":[],"catalog_indices":[455],"catalog_records":[{"agu":{"action":"Store","address_kind":"Immediate","offset_scale":2,"prefetch_returns_address":false,"signed_load":false,"size_bytes":4,"update_mode":"None"},"asm":"swi SrcL, [SrcR, simm]","constraints":[],"encoding":[{"index":0,"mask":"0x0000707f","match":"0x00002059","width_bits":32}],"encoding_kind":"L32","fields":[{"name":"SrcL","pieces":[{"instruction_lsb":15,"value_lsb":0,"width":5}],"signedness":"encoding-defined","width":5},{"name":"SrcR","pieces":[{"instruction_lsb":20,"value_lsb":0,"width":5}],"signedness":"encoding-defined","width":5},{"name":"simm12","pieces":[{"instruction_lsb":25,"value_lsb":0,"width":7},{"instruction_lsb":7,"value_lsb":7,"width":5}],"signedness":"signed","width":12}],"form_id":"swi_32_147e55489c41","length_bits":32,"mnemonic":"SWI","semantic_family":"AGU","semantic_group":"STA/BASE_IMM","semantic_handler":"ExecuteScalarStore","semantic_summary":"SWI snapshots its scalar sources, forms its encoded address, and stores one aligned little-endian 4-byte value.","status":"accepted"}],"classification":["agu"],"contract":{"block_composition":["none"],"canonical_assembly":["swi SrcL, [SrcR, simm]"],"defaults":["Every displayed operand field is encoded explicitly; encoded zero is a value and never denotes omission."],"encoding_class":"standalone-encoded","examples":["swi SrcL, [SrcR, simm]"],"exceptions":["A fixed-bit mismatch, reserved field value, or unavailable selected T/U source raises Fault_IllegalInstruction before instruction effects.","A misaligned 4-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.","SrcR":"Encoded zero reads the architectural zero GPR.","simm12":"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.","simm12 assigns every signed 12-bit value -2048..2047; the encoded byte displacement is that value multiplied by 4.","Each memory address must be aligned to the 4-byte access size; a 4-byte access is the complete transfer unit."],"memory_effects":["After complete preflight, perform one little-endian 4-byte store and record one relaxed store event.","A successful overlapping store invalidates the overlapping reservation; a nonoverlapping reservation remains valid."],"operands":[{"field":"SrcL","role":"Reg5 store-data source"},{"field":"SrcR","role":"Reg5 address-base source"},{"field":"simm12","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 4-byte memory operation, publish any result or writeback, and then advance TPC."],"standalone_opcode":true,"state_effects":["Sign-extend simm12, multiply it by 4, and add it modulo 2^PTO_XLEN to the SrcR base.","Snapshot every store-data source before any memory effect or destination publication.","Successful execution advances TPC by 4 bytes; a rejected or faulting attempt does not retire."]},"depends_on":["PTO-BLOCK-MODEL-SCHEMA-PROFILE-ENCODING"],"id":"PTO-SCALAR-SWI","mnemonic":"SWI","summary":"SWI snapshots its scalar sources, forms its encoded address, and stores one aligned little-endian 4-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"]}// NDF-BEGIN: PTO-SWI-ADR-CONTRACT-001// ndf: kind=contract level=L1 layer=scalar status=accepted// Decisions: ADR-0024, ADR-0029.// SWI MUST snapshot scalar address/data sources, apply its mnemonic// width and address-update mode, preflight access before effects, then commit// the store event and any base update at the defined restart boundary.// NDF-END: PTO-SWI-ADR-CONTRACT-001// DOC-BEGIN: decodereadonly func InstructionContractOperation_SWI() => ScalarOperationbegin return ScalarOperation_SWI;end;// DOC-END: decode// DOC-BEGIN: operationreadonly func InstructionContractHandler_SWI() => ScalarSemanticHandlerbegin return ScalarHandler_ExecuteScalarStore;end;
pure func InstructionContractAGUAction_SWI() => ScalarAGUActionbegin return ScalarAGU_Store;end;
pure func InstructionContractAGUAddressKind_SWI() => ScalarAGUAddressKindbegin return ScalarAGU_Immediate;end;
pure func InstructionContractAGUSizeBytes_SWI() => integer {1,2,4,8}begin return 4;end;
pure func InstructionContractAGUOffsetScale_SWI() => integer {0..3}begin return 2;end;
pure func InstructionContractAGUUpdateMode_SWI() => AddressUpdateModebegin return AddressUpdate_None;end;
pure func InstructionContractAGUSignedLoad_SWI() => booleanbegin return FALSE;end;
pure func InstructionContractAGUPrefetchReturnsAddress_SWI() => booleanbegin return FALSE;end;// DOC-END: operation
SWI is a standalone 32-bit AGU instruction that forms a signed-immediate address and stores one aligned little-endian 4-byte value.
SWI sign-extends simm12 from its complete -2048..2047 domain, multiplies it by 4, and adds the displacement modulo 2^PTO_XLEN to the snapshotted SrcR base.
After complete preflight, the instruction performs one little-endian 4-byte store from its snapshotted store-data source.
This form performs no base-register writeback; its effective address is used only by the selected memory operation.
SrcR supplies the base; simm12 supplies the signed displacement. Every encoded Reg5 source among SrcL, SrcR uses codes 0..23 for GPRs, 24..27 for T#1..T#4, and 28..31 for U#1..U#4 without consumption.SrcL supplies store data.simm12 assigns every signed value from -2048 through 2047; encoded zero is a zero displacement, not omission.All explicit and implicit scalar sources are snapshotted before memory or destination effects, so aliases observe pre-instruction values.
A successful attempt records one relaxed store event, invalidates an overlapping reservation but preserves a nonoverlapping one, and advances TPC by 4 bytes.
Each effective address must satisfy 4-byte alignment. Misalignment raises Fault_DataAlignment before translation; a later permission or bounded-memory failure raises Fault_DataPage at the original address.
A fault records no successful memory event, performs no partial memory, destination, or writeback effect, preserves pending writeback, and leaves the faulting TPC available for full reissue.
A fixed-bit mismatch, reserved field value, or unavailable selected T/U source raises Fault_IllegalInstruction before instruction effects.
This example demonstrates the address calculation only; exact behavior remains in the current ASL and instruction contract.
With the base set to 0x100 and the signed immediate set to 2, the displacement is 8 and base plus displacement is 0x108. The memory access uses 0x108. If aligned and permitted, the instruction stores 4 bytes at that address.
Bodies come from owning ASL. Dragging or buttons change only this page-session view order.
Decisions: ADR-0024, ADR-0029. SWI MUST snapshot scalar address/data sources, apply its mnemonic width and address-update mode, preflight access before effects, then commit the store event and any base update at the defined restart boundary.
PTO-SWI-ADR-CONTRACT-001asl/scalar/agu/SWI.asl813975598708f3b24ce1b2c0c29f29c68801ede6c850ef970af120f54aa3ff64dee11ec588bb65862a1efb6400462a284d07b00c4e13945b645aaab755ff04e813 matching entries
PTO-AVS-AGU-SWI-ALIAS-001tests/asl/scalar/agu/SWI/scalar-exec-swi-registers-001.asl69ecaf1dbed737c62e466997aaeaae18508c9b7e17dc3ee3f480036db13382d3PTO-AVS-AGU-SWI-BOUND-001tests/asl/scalar/agu/SWI/scalar-bound-swi-address-001.aslc65fa2ba714f799c1a00cc12c1f2d7134569f27c271d3b8444d283f49982e0afPTO-AVS-AGU-SWI-EXEC-001tests/asl/scalar/agu/SWI/scalar-exec-swi-direct-001.asl52c554b4adbe01f642fb704c0fb019169e954dec943c5305f8cc4256d2b35d3fPTO-AVS-AGU-SWI-FAULT-001tests/asl/scalar/agu/SWI/scalar-fault-swi-precise-001.asl004e0258f53360ee58649896caf3d1b7c41f4fac665a08b45529bfecd09eef22PTO-AVS-SCALAR-SWI-DECODE-001tests/asl/scalar/agu/SWI/scalar-decode-swi-canonical-001.asl6b79410b30b5a820c5b5f3333e7e0de35701ddf91373283d7840bb39ec005ad1PTO-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.mdf18d13f735cfaf9f2803c754c5818f4af33d1cc42c489f0d9ce060b07bb3a196Loading ADR-0084…
ADR-0084docs/status/decisions/0084-scalar-system-and-queue-operations.mde068992fa81e2c4ac46e492391a2f784141d68e041bf0b9e0586c37217d1e08c{
"classification": [
"agu"
],
"documentation": "docs/scalar/agu/SWI.md",
"id": "PTO-SCALAR-SWI",
"instruction_contract": {
"artifact": "spec/evidence/instruction-contract-closure.json",
"mnemonic": "SWI",
"ndf_clause": "PTO-INST-SCALAR-SWI"
},
"mnemonic": "SWI",
"readiness_subjects": [
"ADR-0029",
"ADR-0059",
"ADR-0084"
],
"semantic_tests": [
"PTO-AVS-AGU-SWI-ALIAS-001",
"PTO-AVS-AGU-SWI-BOUND-001",
"PTO-AVS-AGU-SWI-EXEC-001",
"PTO-AVS-AGU-SWI-FAULT-001"
],
"source": "asl/scalar/agu/SWI.asl",
"surface": "scalar",
"tests": [
"PTO-AVS-AGU-SWI-ALIAS-001",
"PTO-AVS-AGU-SWI-BOUND-001",
"PTO-AVS-AGU-SWI-EXEC-001",
"PTO-AVS-AGU-SWI-FAULT-001",
"PTO-AVS-SCALAR-SWI-DECODE-001"
]
}0.58.5 · Release candidate7dc8b7e5b121d2b2499a2273bebff29e2cd86812813975598708f3b24ce1b2c0c29f29c68801ede6c850ef970af120f54aa3ff64c7dd78ca785d1dbec102d4694f0fb094e9ee39d59752e373d07390197cbfdf38asl/scalar/agu/SWI.aslasl/scalar/agu/SWI.aslasl/scalar/agu/SWI.asl