操作数与参数
RegDst- Reg5 destination or discard
SrcL- Reg5 source; low 32 bits used
shamt- five-bit shift amount
SRAIW performs a word arithmetic right shift and sign-extends the result.
PTO-SCALAR-SRAIWsraiw SrcL, shamt, ->{t, u, Rd}| 字段 | 位宽 | 有符号性 | 架构角色 | 编码零 |
|---|---|---|---|---|
RegDst | 5 | encoding-defined | Reg5 destination or discard | Encoded zero discards the result. |
SrcL | 5 | encoding-defined | Reg5 source; low 32 bits used | Encoded zero reads the architectural zero GPR. |
shamt | 5 | encoding-defined | five-bit shift amount | Encoded zero performs no shift. |
Loading WaveDrom diagram… The encoding table and WaveJSON remain available below.
| Decoded item | Bit range | Value |
|---|---|---|
| Constant | 31:25 | 7'b0000000 |
| shamt | 24:20 | variable |
| SrcL | 19:15 | variable |
| Constant | 14:12 | 3'b110 |
| RegDst | 11:7 | variable |
| Constant | 6:0 | 7'b0110101 |
{
"reg": [
{
"bits": 7,
"name": "7'b0110101"
},
{
"bits": 5,
"name": "RegDst"
},
{
"bits": 3,
"name": "3'b110"
},
{
"bits": 5,
"name": "SrcL"
},
{
"bits": 5,
"name": "shamt"
},
{
"bits": 7,
"name": "7'b0000000"
}
],
"config": {
"bits": 32,
"fontsize": 13,
"hspace": 900,
"lanes": 1,
"offset": 0
}
}sraiw SrcL, shamt, ->{t, u, Rd}
RegDstSrcLshamt下面是该指令所有者中的 Operation;页面没有重写这段行为。
readonly func InstructionContractOperation_SRAIW() => ScalarOperationbegin return ScalarOperation_SRAIW;end;readonly func InstructionContractHandler_SRAIW() => ScalarSemanticHandlerbegin return ScalarHandler_ScalarBinaryW;end;
pure func InstructionContractShiftWidth_SRAIW() => integer {1..64}begin return 5;end;
pure func InstructionContractIsWordOperation_SRAIW() => booleanbegin return TRUE;end;// PTO-INSTRUCTION: {"assembly":["sraiw SrcL, shamt, ->{t, u, Rd}"],"block":[],"catalog_indices":[427],"catalog_records":[{"asm":"sraiw SrcL, shamt, ->{t, u, Rd}","constraints":[],"encoding":[{"index":0,"mask":"0xfe00707f","match":"0x00006035","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":"shamt","pieces":[{"instruction_lsb":20,"value_lsb":0,"width":5}],"signedness":"encoding-defined","width":5}],"form_id":"sraiw_32_db04a6299504","length_bits":32,"mnemonic":"SRAIW","semantic_family":"ALU","semantic_group":"ALU","semantic_handler":"ScalarBinaryW","semantic_summary":"SRAIW arithmetically shifts SrcL[31:0] right by the encoded five-bit amount, sign-extends the word result to XLEN, and publishes it.","status":"accepted"}],"classification":["alu"],"contract":{"block_composition":["none"],"canonical_assembly":["sraiw SrcL, shamt, ->{t, u, Rd}"],"defaults":["SrcL, shamt, and RegDst are required fields; no field can be omitted.","shamt is a 5-bit shift amount from 0 through 31. Encoded zero performs an identity word shift."],"encoding_class":"standalone-encoded","examples":["sraiw a0, 1, ->a0","sraiw u#1, 31, ->t","sraiw zero, 0, ->zero"],"exceptions":["SRAIW raises no arithmetic exception; copies of SrcL[31] enter from the left and the final word is sign-extended to XLEN.","Bits 31:25 are fixed zero. A mismatch or unavailable T/U source raises Fault_IllegalInstruction before the destination effect and TPC advance."],"field_contracts":{},"field_zero_meanings":{"RegDst":"Encoded zero discards the result.","SrcL":"Encoded zero reads the architectural zero GPR.","shamt":"Encoded zero performs no shift."},"legality":["SrcL 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, code 30 pushes U, code 31 pushes T, and codes 1..23 write GPRs.","Every 5-bit shift amount from 0 through 31 is legal; source bits above bit 31 do not participate."],"memory_effects":["none"],"operands":[{"field":"RegDst","role":"Reg5 destination or discard"},{"field":"SrcL","role":"Reg5 source; low 32 bits used"},{"field":"shamt","role":"five-bit shift amount"}],"ordering":["Snapshot SrcL before the destination effect so aliases read the pre-instruction value.","Publish the sign-extended word result, then advance TPC by four bytes."],"standalone_opcode":true,"state_effects":["Compute the 32-bit arithmetic right shift ASR(SrcL[31:0], shamt), then publish the 32-bit result sign-extended to XLEN.","Destination codes 0 and 24..29 discard, code 30 pushes U, code 31 pushes T, and codes 1..23 write GPRs; source queues are non-consuming.","No memory, reservation, descriptor, flag, block, privilege, or control-flow state changes except the successful TPC advance."]},"depends_on":["PTO-BLOCK-MODEL-SCHEMA-PROFILE-ENCODING"],"id":"PTO-SCALAR-SRAIW","mnemonic":"SRAIW","summary":"SRAIW performs a word arithmetic right shift and sign-extends the result.","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-SRAIW-ADR-CONTRACT-001// ndf: kind=contract level=L1 layer=scalar status=accepted// Decisions: ADR-0026.// SRAIW MUST snapshot its scalar sources, apply its mnemonic-owned// width, immediate, modifier, and wrapping rule, then publish through the// assigned destination or commit effect in alias-safe order.// NDF-END: PTO-SRAIW-ADR-CONTRACT-001// DOC-BEGIN: decodereadonly func InstructionContractOperation_SRAIW() => ScalarOperationbegin return ScalarOperation_SRAIW;end;// DOC-END: decode// DOC-BEGIN: operationreadonly func InstructionContractHandler_SRAIW() => ScalarSemanticHandlerbegin return ScalarHandler_ScalarBinaryW;end;
pure func InstructionContractShiftWidth_SRAIW() => integer {1..64}begin return 5;end;
pure func InstructionContractIsWordOperation_SRAIW() => booleanbegin return TRUE;end;// DOC-END: operation
SRAIW 是一条 32 位标量 ALU 指令。它按照低 32 位字,再符号扩展到 XLEN移位规则对源值执行算术右移;当前指令契约定义结果发布路径以及任何额外状态效果。
执行时先对编码输入做快照,然后按照低 32 位字,再符号扩展到 XLEN移位规则对源值执行算术右移,最后才产生目标效果。
RegDst 是 5 位字段,选择 Reg5 结果目标,或丢弃结果。SrcL 是 5 位字段,通过 Reg5 选择标量输入,其中使用低 32 位。shamt 是 5 位字段,编码五位移位量。这些角色来自当前指令契约;T/U 源只被读取和快照,不会因源选择而出队。编码零的精确含义列在下方生成的默认值章节中。
所有标量源都在目标效果前完成快照。完成后的值随后通过 RegDst 按当前标量目标映射发布。
该 ALU 操作不产生内存效果。成功完成架构效果后,TPC 前进 4 字节。
该操作不会产生隐藏的标量发布目标或隐式内存访问。架构变化仅限于当前契约列出的状态效果。
编码移位量的 5 位全部已分配,范围为 0..31;该移位按固定位宽获得总定义,不产生算术异常。
下方生成的合法性表是已分配字段值、保留编码和目标丢弃编码的权威说明。解码与源可用性检查先于架构效果完成。
本示例只用于演示当前 ASL 所有者,不替代规范操作。
以一个小型 SRAIW 示例说明:源值 -8 算术右移 2 位后得到 -2。
正文来自 owning ASL。拖拽或按钮只临时改变当前页面显示顺序。
Decisions: ADR-0026. SRAIW MUST snapshot its scalar sources, apply its mnemonic-owned width, immediate, modifier, and wrapping rule, then publish through the assigned destination or commit effect in alias-safe order.
PTO-SRAIW-ADR-CONTRACT-001asl/scalar/alu/SRAIW.asl652262e15f7fd3e9ad8db234bb476f0e188fd43fab7743772676d89836fef12863382e165bae4c1615ddbf49a907d4437772df128ef4dfbbc859a1584711888f11 matching entries
PTO-AVS-SCALAR-SRAIW-DECODE-001tests/asl/scalar/alu/SRAIW/scalar-decode-sraiw-canonical-001.asld8534bd718808707dfc9294bb6f03f226d8fc50397b125084ca0f2baf70f7084PTO-AVS-SCALAR-SRAIW-MAXIMUM-001tests/asl/scalar/alu/SRAIW/scalar-exec-sraiw-maximum-001.asl89c97f41cf2c150af334679b369e59dbb4907841aede8e717bdd63c27560b382PTO-AVS-SCALAR-SRAIW-ZERO-001tests/asl/scalar/alu/SRAIW/scalar-bound-sraiw-zero-001.asl37ba7359e451f93ac6784b6b8aa703e4f861bf961e2faf72aed15a88d763d47fPTO-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.mdf18d13f735cfaf9f2803c754c5818f4af33d1cc42c489f0d9ce060b07bb3a196Loading ADR-0084…
ADR-0084docs/status/decisions/0084-scalar-system-and-queue-operations.mde068992fa81e2c4ac46e492391a2f784141d68e041bf0b9e0586c37217d1e08c{
"classification": [
"alu"
],
"documentation": "docs/scalar/alu/SRAIW.md",
"id": "PTO-SCALAR-SRAIW",
"instruction_contract": {
"artifact": "spec/evidence/instruction-contract-closure.json",
"mnemonic": "SRAIW",
"ndf_clause": "PTO-INST-SCALAR-SRAIW"
},
"mnemonic": "SRAIW",
"readiness_subjects": [
"ADR-0026",
"ADR-0059",
"ADR-0084"
],
"semantic_tests": [
"PTO-AVS-SCALAR-SRAIW-MAXIMUM-001",
"PTO-AVS-SCALAR-SRAIW-ZERO-001"
],
"source": "asl/scalar/alu/SRAIW.asl",
"surface": "scalar",
"tests": [
"PTO-AVS-SCALAR-SRAIW-DECODE-001",
"PTO-AVS-SCALAR-SRAIW-MAXIMUM-001",
"PTO-AVS-SCALAR-SRAIW-ZERO-001"
]
}0.58.5 · 候选发布7dc8b7e5b121d2b2499a2273bebff29e2cd86812652262e15f7fd3e9ad8db234bb476f0e188fd43fab7743772676d89836fef128c9a507a6d70ea661c5d5ba6a67fa8ecea7d0729e859c0447907abdb52ddf3c49asl/scalar/alu/SRAIW.aslasl/scalar/alu/SRAIW.aslasl/scalar/alu/SRAIW.asl