Operands and parameters
SrcD- Reg5 first store-data source
SrcL- Reg5 address-base source
SrcR- Reg5 register-offset source
SrcRType- register-offset transformation selector
SW.U snapshots its scalar sources, forms its encoded address, and stores one aligned little-endian 4-byte value.
PTO-SCALAR-SW-Usw.u SrcD, [SrcL, SrcR<{.sw,.uw,.neg}>]| Field | Bits | Signedness | Architectural role | Encoded zero |
|---|---|---|---|---|
SrcD | 5 | encoding-defined | Reg5 first store-data source | Encoded zero reads the architectural zero GPR. |
SrcL | 5 | encoding-defined | Reg5 address-base source | Encoded zero reads the architectural zero GPR. |
SrcR | 5 | encoding-defined | Reg5 register-offset source | Encoded zero reads the architectural zero GPR. |
SrcRType | 2 | encoding-defined | register-offset transformation selector | Encoded zero leaves the complete PTO_XLEN register-offset value unchanged. |
Loading WaveDrom diagram… The encoding table and WaveJSON remain available below.
| Decoded item | Bit range | Value |
|---|---|---|
| SrcD | 31:27 | variable |
| SrcRType | 26:25 | variable |
| SrcR | 24:20 | variable |
| SrcL | 19:15 | variable |
| Constant | 14:0 | 15'b110000001001001 |
{
"reg": [
{
"bits": 15,
"name": "15'b110000001001001"
},
{
"bits": 5,
"name": "SrcL"
},
{
"bits": 5,
"name": "SrcR"
},
{
"bits": 2,
"name": "SrcRType"
},
{
"bits": 5,
"name": "SrcD"
}
],
"config": {
"bits": 32,
"fontsize": 13,
"hspace": 900,
"lanes": 1,
"offset": 0
}
}sw.u SrcD, [SrcL, SrcR<{.sw,.uw,.neg}>]
SrcDSrcLSrcRSrcRTypeThis Operation comes directly from the instruction owner; the page does not rewrite its behavior.
readonly func InstructionContractOperation_SW_U() => ScalarOperationbegin return ScalarOperation_SW_U;end;readonly func InstructionContractHandler_SW_U() => ScalarSemanticHandlerbegin return ScalarHandler_ExecuteScalarStore;end;
pure func InstructionContractAGUAction_SW_U() => ScalarAGUActionbegin return ScalarAGU_Store;end;
pure func InstructionContractAGUAddressKind_SW_U() => ScalarAGUAddressKindbegin return ScalarAGU_Register;end;
pure func InstructionContractAGUSizeBytes_SW_U() => integer {1,2,4,8}begin return 4;end;
pure func InstructionContractAGUOffsetScale_SW_U() => integer {0..3}begin return 0;end;
pure func InstructionContractAGUUpdateMode_SW_U() => AddressUpdateModebegin return AddressUpdate_None;end;
pure func InstructionContractAGUSignedLoad_SW_U() => booleanbegin return FALSE;end;
pure func InstructionContractAGUPrefetchReturnsAddress_SW_U() => booleanbegin return FALSE;end;// PTO-INSTRUCTION: {"assembly":["sw.u SrcD, [SrcL, SrcR<{.sw,.uw,.neg}>]"],"block":[],"catalog_indices":[447],"catalog_records":[{"agu":{"action":"Store","address_kind":"Register","offset_scale":0,"prefetch_returns_address":false,"signed_load":false,"size_bytes":4,"update_mode":"None"},"asm":"sw.u SrcD, [SrcL, SrcR<{.sw,.uw,.neg}>]","constraints":[],"encoding":[{"index":0,"mask":"0x00007fff","match":"0x00006049","width_bits":32}],"encoding_kind":"L32","fields":[{"name":"SrcD","pieces":[{"instruction_lsb":27,"value_lsb":0,"width":5}],"signedness":"encoding-defined","width":5},{"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":"SrcRType","pieces":[{"instruction_lsb":25,"value_lsb":0,"width":2}],"signedness":"encoding-defined","width":2}],"form_id":"sw_u_32_718a61f75d33","length_bits":32,"mnemonic":"SW.U","semantic_family":"AGU","semantic_group":"STA/BASE_REG","semantic_handler":"ExecuteScalarStore","semantic_summary":"SW.U 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":["sw.u SrcD, [SrcL, SrcR<{.sw,.uw,.neg}>]"],"defaults":["Every displayed operand field is encoded explicitly; encoded zero is a value and never denotes omission.","SrcRType=0 leaves SrcR unchanged, SrcRType=1 sign-extends SrcR[31:0], SrcRType=2 zero-extends SrcR[31:0], and SrcRType=3 negates the full PTO_XLEN value. Encoded shamt zero performs no shift."],"encoding_class":"standalone-encoded","examples":["sw.u SrcD, [SrcL, SrcR<{.sw,.uw,.neg}>]"],"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":{"SrcD":"Encoded zero reads the architectural zero GPR.","SrcL":"Encoded zero reads the architectural zero GPR.","SrcR":"Encoded zero reads the architectural zero GPR.","SrcRType":"Encoded zero leaves the complete PTO_XLEN register-offset value unchanged."},"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.","All four SrcRType values and all shamt values 0..31 are assigned; apply the modifier before the shift.","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":"SrcD","role":"Reg5 first store-data source"},{"field":"SrcL","role":"Reg5 address-base source"},{"field":"SrcR","role":"Reg5 register-offset source"},{"field":"SrcRType","role":"register-offset transformation selector"}],"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":["Form offset = LSL(Modify(SrcR, SrcRType), 0) and add it modulo 2^PTO_XLEN to the SrcL 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-SW-U","mnemonic":"SW.U","summary":"SW.U 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-SW-U-ADR-CONTRACT-001// ndf: kind=contract level=L1 layer=scalar status=accepted// Decisions: ADR-0024, ADR-0029.// SW.U 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-SW-U-ADR-CONTRACT-001// DOC-BEGIN: decodereadonly func InstructionContractOperation_SW_U() => ScalarOperationbegin return ScalarOperation_SW_U;end;// DOC-END: decode// DOC-BEGIN: operationreadonly func InstructionContractHandler_SW_U() => ScalarSemanticHandlerbegin return ScalarHandler_ExecuteScalarStore;end;
pure func InstructionContractAGUAction_SW_U() => ScalarAGUActionbegin return ScalarAGU_Store;end;
pure func InstructionContractAGUAddressKind_SW_U() => ScalarAGUAddressKindbegin return ScalarAGU_Register;end;
pure func InstructionContractAGUSizeBytes_SW_U() => integer {1,2,4,8}begin return 4;end;
pure func InstructionContractAGUOffsetScale_SW_U() => integer {0..3}begin return 0;end;
pure func InstructionContractAGUUpdateMode_SW_U() => AddressUpdateModebegin return AddressUpdate_None;end;
pure func InstructionContractAGUSignedLoad_SW_U() => booleanbegin return FALSE;end;
pure func InstructionContractAGUPrefetchReturnsAddress_SW_U() => booleanbegin return FALSE;end;// DOC-END: operation
SW.U is a standalone 32-bit AGU instruction that forms a register-offset address and stores one aligned little-endian 4-byte value.
SW.U transforms SrcR according to SrcRType and adds the unscaled result modulo 2^PTO_XLEN to the snapshotted SrcL 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.
SrcL supplies the base; SrcR supplies the offset; SrcRType supplies the offset transformation. Every encoded Reg5 source among SrcD, 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.SrcD supplies store data.SrcRType values 0..3 are assigned; the selected transformation is applied before the form's fixed scaling.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 base 0x100, unchanged offset source 4, and the fixed shift 0, the aligned displacement is 4 and base plus displacement is 0x104. The memory access uses 0x104. If permitted, the instruction stores 4 bytes at that aligned address.
Bodies come from owning ASL. Dragging or buttons change only this page-session view order.
Decisions: ADR-0024, ADR-0029. SW.U 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-SW-U-ADR-CONTRACT-001asl/scalar/agu/SW.U.asl2d87fa812c6c76458fbf3476dea3625d0ed3c255bbd0110951f409f3009a2d8bdcf8c56dcd446698484675541780bacac2ba44311af85c6f4e0a70e2b3351aab13 matching entries
PTO-AVS-AGU-SW-U-ALIAS-001tests/asl/scalar/agu/SW.U/scalar-exec-sw-u-registers-001.asl765e8f6111f45619471d67a6a64d76cd83ae8a2f8090669a0f2295ab17426ecdPTO-AVS-AGU-SW-U-BOUND-001tests/asl/scalar/agu/SW.U/scalar-bound-sw-u-address-001.aslbc1087a8f888360eab85df75db296d534e333aa1435689dc29f24fa4acebaaf9PTO-AVS-AGU-SW-U-EXEC-001tests/asl/scalar/agu/SW.U/scalar-exec-sw-u-direct-001.asl0ef4f7d919cb734be1890b97e75794ec22c4a54a9721637834ed572a4c1a1666PTO-AVS-AGU-SW-U-FAULT-001tests/asl/scalar/agu/SW.U/scalar-fault-sw-u-precise-001.asl945239dd7958b84f74af7eac52240caeb57a0f9aea76dfda5f7e76975eff50a5PTO-AVS-SCALAR-SW-U-DECODE-001tests/asl/scalar/agu/SW.U/scalar-decode-sw-u-canonical-001.asl3beba74b14df77f44a541f71325ccd6f0aef2a1be868992287feef4b97930f12PTO-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/SW.U.md",
"id": "PTO-SCALAR-SW-U",
"instruction_contract": {
"artifact": "spec/evidence/instruction-contract-closure.json",
"mnemonic": "SW.U",
"ndf_clause": "PTO-INST-SCALAR-SW-U"
},
"mnemonic": "SW.U",
"readiness_subjects": [
"ADR-0029",
"ADR-0059",
"ADR-0084"
],
"semantic_tests": [
"PTO-AVS-AGU-SW-U-ALIAS-001",
"PTO-AVS-AGU-SW-U-BOUND-001",
"PTO-AVS-AGU-SW-U-EXEC-001",
"PTO-AVS-AGU-SW-U-FAULT-001"
],
"source": "asl/scalar/agu/SW.U.asl",
"surface": "scalar",
"tests": [
"PTO-AVS-AGU-SW-U-ALIAS-001",
"PTO-AVS-AGU-SW-U-BOUND-001",
"PTO-AVS-AGU-SW-U-EXEC-001",
"PTO-AVS-AGU-SW-U-FAULT-001",
"PTO-AVS-SCALAR-SW-U-DECODE-001"
]
}0.58.5 · Release candidate7dc8b7e5b121d2b2499a2273bebff29e2cd868122d87fa812c6c76458fbf3476dea3625d0ed3c255bbd0110951f409f3009a2d8bd06f17cb7c451f14e0ce8570d52f708df0411430a2e081761dfd687fc0751189asl/scalar/agu/SW.U.aslasl/scalar/agu/SW.U.aslasl/scalar/agu/SW.U.asl