Operands and parameters
RegDst- Reg5 destination or discard
SrcL- dividend Reg5 source
SrcR- divisor Reg5 source
REMUW computes the unsigned low-32-bit remainder using total fixed-width semantics and publishes the XLEN result.
PTO-SCALAR-REMUWremuw SrcL, SrcR, ->{t, u, Rd}| Field | Bits | Signedness | Architectural role | Encoded zero |
|---|---|---|---|---|
RegDst | 5 | encoding-defined | Reg5 destination or discard | Encoded zero discards the result. |
SrcL | 5 | encoding-defined | dividend Reg5 source | Encoded zero reads the architectural zero GPR dividend. |
SrcR | 5 | encoding-defined | divisor Reg5 source | Encoded zero reads the architectural zero GPR divisor and therefore selects the defined zero-divisor result. |
Loading WaveDrom diagram… The encoding table and WaveJSON remain available below.
| Decoded item | Bit range | Value |
|---|---|---|
| Constant | 31:25 | 7'b0000000 |
| SrcR | 24:20 | variable |
| SrcL | 19:15 | variable |
| Constant | 14:12 | 3'b111 |
| RegDst | 11:7 | variable |
| Constant | 6:0 | 7'b1010111 |
{
"reg": [
{
"bits": 7,
"name": "7'b1010111"
},
{
"bits": 5,
"name": "RegDst"
},
{
"bits": 3,
"name": "3'b111"
},
{
"bits": 5,
"name": "SrcL"
},
{
"bits": 5,
"name": "SrcR"
},
{
"bits": 7,
"name": "7'b0000000"
}
],
"config": {
"bits": 32,
"fontsize": 13,
"hspace": 900,
"lanes": 1,
"offset": 0
}
}remuw SrcL, SrcR, ->{t, u, Rd}
RegDstSrcLSrcRThis Operation comes directly from the instruction owner; the page does not rewrite its behavior.
readonly func InstructionContractOperation_REMUW() => ScalarOperationbegin return ScalarOperation_REMUW;end;readonly func InstructionContractHandler_REMUW() => ScalarSemanticHandlerbegin return ScalarHandler_ScalarRemainderUnsignedW;end;pure func InstructionContractResult_REMUW( dividend: Word, divisor: Word) => Wordbegin return ScalarRemainderUnsignedW( dividend, divisor);end;// PTO-INSTRUCTION: {"assembly":["remuw SrcL, SrcR, ->{t, u, Rd}"],"block":[],"catalog_indices":[374],"catalog_records":[{"asm":"remuw SrcL, SrcR, ->{t, u, Rd}","constraints":[],"encoding":[{"index":0,"mask":"0xfe00707f","match":"0x00007057","width_bits":32}],"encoding_kind":"L32","fields":[{"name":"RegDst","pieces":[{"instruction_lsb":7,"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}],"form_id":"remuw_32_f10ade2f5ccb","length_bits":32,"mnemonic":"REMUW","semantic_family":"ALU","semantic_group":"ALU","semantic_handler":"ScalarRemainderUnsignedW","semantic_summary":"REMUW computes the unsigned low-32-bit remainder using total fixed-width semantics and publishes the XLEN result.","status":"accepted"}],"classification":["alu"],"contract":{"block_composition":["none"],"canonical_assembly":["remuw SrcL, SrcR, ->{t, u, Rd}"],"defaults":["SrcL, SrcR, and RegDst are required encoded fields; no field can be omitted.","There is no encoded arithmetic mode or implicit operand. The mnemonic fixes signedness, operand width, and quotient-versus-remainder selection."],"encoding_class":"standalone-encoded","examples":["remuw a0, a1, ->a2","remuw t#1, zero, ->u"],"exceptions":["Division and remainder are total: zero divisors and signed minimum divided by negative one do not raise an arithmetic exception.","An unavailable selected T/U source raises Fault_IllegalInstruction before the destination effect and before TPC advances."],"field_contracts":{},"field_zero_meanings":{"RegDst":"Encoded zero discards the result.","SrcL":"Encoded zero reads the architectural zero GPR dividend.","SrcR":"Encoded zero reads the architectural zero GPR divisor and therefore selects the defined zero-divisor result."},"legality":["SrcL and SrcR codes 0..23 select absolute GPRs, 24..27 select T#1..T#4, and 28..31 select U#1..U#4 without consumption.","RegDst codes 0 and 24..29 discard, codes 1..23 write GPRs, code 30 pushes U, and code 31 pushes T.","Every value of each Reg5 selector is assigned; fixed encoding bits must match the canonical form."],"memory_effects":["none"],"operands":[{"field":"RegDst","role":"Reg5 destination or discard"},{"field":"SrcL","role":"dividend Reg5 source"},{"field":"SrcR","role":"divisor Reg5 source"}],"ordering":["Snapshot both sources before the destination effect so duplicate selectors and destination aliases observe pre-instruction values.","Publish the result, then advance TPC by four bytes."],"standalone_opcode":true,"state_effects":["Interpret each source low 32 bits as unsigned, return the unsigned remainder, then sign-extend the low 32-bit result to XLEN.","A zero low-32-bit divisor returns the sign-extended low 32-bit dividend.","Publish the complete XLEN result through the common Reg5 destination map. Relative sources are non-consuming; only a T or U destination push changes a temporary queue.","No memory, reservation, descriptor, numeric-status, block, privilege, branch-target, or other control state changes. Successful execution advances TPC by four bytes."]},"depends_on":["PTO-BLOCK-MODEL-SCHEMA-PROFILE-ENCODING"],"id":"PTO-SCALAR-REMUW","mnemonic":"REMUW","summary":"REMUW computes the unsigned low-32-bit remainder using total fixed-width semantics and publishes the XLEN result.","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_REMUW() => ScalarOperationbegin return ScalarOperation_REMUW;end;// DOC-END: decode// DOC-BEGIN: operationreadonly func InstructionContractHandler_REMUW() => ScalarSemanticHandlerbegin return ScalarHandler_ScalarRemainderUnsignedW;end;pure func InstructionContractResult_REMUW( dividend: Word, divisor: Word) => Wordbegin return ScalarRemainderUnsignedW( dividend, divisor);end;// DOC-END: operation
REMUW is a 32-bit scalar ALU instruction. It computes the unsigned remainder over the low 32-bit word, followed by sign-extension to XLEN; its current instruction contract defines the result publication path and any additional state effect.
Execution snapshots the encoded inputs, then computes the unsigned remainder over the low 32-bit word, followed by sign-extension to XLEN, and only afterward performs the destination effects.
RegDst field selects the Reg5 result target or discards the result.SrcL field selects the dividend through Reg5.SrcR field selects the divisor through Reg5.These roles come from the current instruction contract. T/U sources are read and snapshotted without being removed from their queues; exact encoded-zero meanings appear in the generated defaults below.
Every scalar source is snapshotted before the destination effect. The completed value is then routed through RegDst using the current scalar destination map.
This ALU operation has no memory effect. After its successful architectural effects, TPC advances by 4 bytes.
The operation does not introduce a hidden scalar publication target or an implicit memory access. Architectural changes remain limited to the state effects enumerated by the current contract.
A zero divisor returns the effective dividend as the remainder; the signed overflow combination returns zero. Neither case raises an arithmetic exception.
The generated legality table is authoritative for assigned field values, reserved encodings, and destination discard codes. Decode and source availability are checked before architectural effects.
This example illustrates the current ASL owner and does not replace the normative operation.
For a small REMUW example, dividend 13 and divisor 5 produce remainder 3.
Bodies come from owning ASL. Dragging or buttons change only this page-session view order.
No NDF clause is attached to this unit.
9 matching entries
PTO-AVS-SCALAR-REMUW-DECODE-001tests/asl/scalar/alu/REMUW/scalar-decode-remuw-canonical-001.asl30986917dd6939898c5d3b0e829dcf1fcbe563d4804d4b281bb9abea2bf23288PTO-AVS-SCALAR-REMUW-TOTALITY-001tests/asl/scalar/alu/REMUW/scalar-exec-remuw-totality-001.asl3138681270864e5abda03de78765d2c32e241c97611881de8f8f185efbcd2efcPTO-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-0026…
ADR-0026docs/status/decisions/0026-scalar-alu-totality-and-alias-order.md41d126f224dddc371832120f1b02eab64e426872fdcbea452bad77c90bdec349Loading ADR-0059…
ADR-0059docs/status/decisions/0059-mnemonic-field-encoding-closure.mdf18d13f735cfaf9f2803c754c5818f4af33d1cc42c489f0d9ce060b07bb3a196{
"classification": [
"alu"
],
"documentation": "docs/scalar/alu/REMUW.md",
"id": "PTO-SCALAR-REMUW",
"instruction_contract": {
"artifact": "spec/evidence/instruction-contract-closure.json",
"mnemonic": "REMUW",
"ndf_clause": "PTO-INST-SCALAR-REMUW"
},
"mnemonic": "REMUW",
"readiness_subjects": [
"ADR-0026",
"ADR-0059"
],
"semantic_tests": [
"PTO-AVS-SCALAR-REMUW-TOTALITY-001"
],
"source": "asl/scalar/alu/REMUW.asl",
"surface": "scalar",
"tests": [
"PTO-AVS-SCALAR-REMUW-DECODE-001",
"PTO-AVS-SCALAR-REMUW-TOTALITY-001"
]
}0.58.5 · Release candidate7dc8b7e5b121d2b2499a2273bebff29e2cd86812a1f34dcb09b431270702377abd00b9b7bcdcb922fead1e8a3dc08583526071254eff9610442f5c59c877e552808f9854670ff3d52e9f8ef72fb44c1c1c9e90feasl/scalar/alu/REMUW.aslasl/scalar/alu/REMUW.asl