Operands and parameters
SrcL- Reg5 store-data source
simm- signed address displacement
SH.PCR snapshots its scalar sources, forms its encoded address, and stores one aligned little-endian 2-byte value.
PTO-SCALAR-SH-PCRsh.pcr SrcL, [symbol]| Field | Bits | Signedness | Architectural role | Encoded zero |
|---|---|---|---|---|
SrcL | 5 | encoding-defined | Reg5 store-data source | Encoded zero reads the architectural zero GPR. |
simm | 17 | 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 |
|---|---|---|
| simm | 31:20 | variable |
| SrcL | 19:15 | variable |
| Constant | 14:12 | 3'b001 |
| simm | 11:7 | variable |
| Constant | 6:0 | 7'b1101001 |
{
"reg": [
{
"bits": 7,
"name": "7'b1101001"
},
{
"bits": 5,
"name": "simm"
},
{
"bits": 3,
"name": "3'b001"
},
{
"bits": 5,
"name": "SrcL"
},
{
"bits": 12,
"name": "simm"
}
],
"config": {
"bits": 32,
"fontsize": 13,
"hspace": 900,
"lanes": 1,
"offset": 0
}
}sh.pcr SrcL, [symbol]
SrcLsimmThis Operation comes directly from the instruction owner; the page does not rewrite its behavior.
readonly func InstructionContractOperation_SH_PCR() => ScalarOperationbegin return ScalarOperation_SH_PCR;end;readonly func InstructionContractHandler_SH_PCR() => ScalarSemanticHandlerbegin return ScalarHandler_ExecuteScalarStore;end;
pure func InstructionContractAGUAction_SH_PCR() => ScalarAGUActionbegin return ScalarAGU_Store;end;
pure func InstructionContractAGUAddressKind_SH_PCR() => ScalarAGUAddressKindbegin return ScalarAGU_PCRelative;end;
pure func InstructionContractAGUSizeBytes_SH_PCR() => integer {1,2,4,8}begin return 2;end;
pure func InstructionContractAGUOffsetScale_SH_PCR() => integer {0..3}begin return 2;end;
pure func InstructionContractAGUUpdateMode_SH_PCR() => AddressUpdateModebegin return AddressUpdate_None;end;
pure func InstructionContractAGUSignedLoad_SH_PCR() => booleanbegin return FALSE;end;
pure func InstructionContractAGUPrefetchReturnsAddress_SH_PCR() => booleanbegin return FALSE;end;// PTO-INSTRUCTION: {"assembly":["sh.pcr SrcL, [symbol]"],"block":[],"catalog_indices":[417],"catalog_records":[{"agu":{"action":"Store","address_kind":"PCRelative","offset_scale":2,"prefetch_returns_address":false,"signed_load":false,"size_bytes":2,"update_mode":"None"},"asm":"sh.pcr SrcL, [symbol]","constraints":[],"encoding":[{"index":0,"mask":"0x0000707f","match":"0x00001069","width_bits":32}],"encoding_kind":"L32","fields":[{"name":"SrcL","pieces":[{"instruction_lsb":15,"value_lsb":0,"width":5}],"signedness":"encoding-defined","width":5},{"name":"simm","pieces":[{"instruction_lsb":20,"value_lsb":0,"width":12},{"instruction_lsb":7,"value_lsb":12,"width":5}],"signedness":"signed","width":17}],"form_id":"sh_pcr_32_14ba505eb3c2","length_bits":32,"mnemonic":"SH.PCR","semantic_family":"AGU","semantic_group":"STA","semantic_handler":"ExecuteScalarStore","semantic_summary":"SH.PCR snapshots its scalar sources, forms its encoded address, and stores one aligned little-endian 2-byte value.","status":"accepted"}],"classification":["agu"],"contract":{"block_composition":["none"],"canonical_assembly":["sh.pcr SrcL, [symbol]"],"defaults":["Every displayed operand field is encoded explicitly; encoded zero is a value and never denotes omission."],"encoding_class":"standalone-encoded","examples":["sh.pcr SrcL, [symbol]"],"exceptions":["A fixed-bit mismatch, reserved field value, or unavailable selected T/U source raises Fault_IllegalInstruction before instruction effects.","A misaligned 2-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.","simm":"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.","simm assigns every signed 17-bit value -65536..65535; the encoded byte displacement is that value multiplied by 4.","Each memory address must be aligned to the 2-byte access size; a 2-byte access is the complete transfer unit."],"memory_effects":["After complete preflight, perform one little-endian 2-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":"simm","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 2-byte memory operation, publish any result or writeback, and then advance TPC."],"standalone_opcode":true,"state_effects":["Clear TPC bits 1:0, sign-extend the encoded displacement, multiply it by four, and add it modulo 2^PTO_XLEN.","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-SH-PCR","mnemonic":"SH.PCR","summary":"SH.PCR snapshots its scalar sources, forms its encoded address, and stores one aligned little-endian 2-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-SH-PCR-ADR-CONTRACT-001// ndf: kind=contract level=L1 layer=scalar status=accepted// Decisions: ADR-0024, ADR-0029.// SH.PCR 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-SH-PCR-ADR-CONTRACT-001// DOC-BEGIN: decodereadonly func InstructionContractOperation_SH_PCR() => ScalarOperationbegin return ScalarOperation_SH_PCR;end;// DOC-END: decode// DOC-BEGIN: operationreadonly func InstructionContractHandler_SH_PCR() => ScalarSemanticHandlerbegin return ScalarHandler_ExecuteScalarStore;end;
pure func InstructionContractAGUAction_SH_PCR() => ScalarAGUActionbegin return ScalarAGU_Store;end;
pure func InstructionContractAGUAddressKind_SH_PCR() => ScalarAGUAddressKindbegin return ScalarAGU_PCRelative;end;
pure func InstructionContractAGUSizeBytes_SH_PCR() => integer {1,2,4,8}begin return 2;end;
pure func InstructionContractAGUOffsetScale_SH_PCR() => integer {0..3}begin return 2;end;
pure func InstructionContractAGUUpdateMode_SH_PCR() => AddressUpdateModebegin return AddressUpdate_None;end;
pure func InstructionContractAGUSignedLoad_SH_PCR() => booleanbegin return FALSE;end;
pure func InstructionContractAGUPrefetchReturnsAddress_SH_PCR() => booleanbegin return FALSE;end;// DOC-END: operation
SH.PCR is a standalone 32-bit AGU instruction that forms a PC-relative address and stores one aligned little-endian 2-byte value.
SH.PCR clears TPC[1:0], sign-extends simm from -65536..65535, multiplies it by 4, and adds the displacement modulo 2^PTO_XLEN to the aligned TPC base.
After complete preflight, the instruction performs one little-endian 2-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.
TPC supplies the aligned implicit base; simm supplies the signed displacement. Every encoded Reg5 source among SrcL 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.simm assigns every signed value from -65536 through 65535; 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 2-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 aligned TPC=0x100 and the encoded displacement set to 2, the byte displacement is 8 and the effective address is 0x108. The memory access uses 0x108. If aligned and permitted, the instruction stores 2 bytes at that address.
Bodies come from owning ASL. Dragging or buttons change only this page-session view order.
Decisions: ADR-0024, ADR-0029. SH.PCR 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-SH-PCR-ADR-CONTRACT-001asl/scalar/agu/SH.PCR.asl2261217024776f7903bfe29ba454a9eed7fc0e1b8d38892e5e2a999e08f815928389fe54d0201c39277572b983bed83710adcb0c6c0cc5f289b760a934d1f5a214 matching entries
PTO-AVS-AGU-SH-PCR-ALIAS-001tests/asl/scalar/agu/SH.PCR/scalar-exec-sh-pcr-registers-001.aslbdbdb486b9666eecf50530f533cfd010a0057c93641795dbc34c981b7a064290PTO-AVS-AGU-SH-PCR-BOUND-001tests/asl/scalar/agu/SH.PCR/scalar-bound-sh-pcr-address-001.asl70f66350b49beb7b7c4b849819938fdf46fc63724cba061527260c013805fcbbPTO-AVS-AGU-SH-PCR-EXEC-001tests/asl/scalar/agu/SH.PCR/scalar-exec-sh-pcr-direct-001.asl317e9b5b7e9c41b4e86b718b0be132d3472174cd02d2a1b1ee56f01c024f6983PTO-AVS-AGU-SH-PCR-FAULT-001tests/asl/scalar/agu/SH.PCR/scalar-fault-sh-pcr-precise-001.asl8637c07198185b2708c39e769a67e5006b6ce9e316fef961c548c50f9b07d018PTO-AVS-SCALAR-SH-PCR-DECODE-001tests/asl/scalar/agu/SH.PCR/scalar-decode-sh-pcr-canonical-001.asl573b37d13ddccf1d8e5a86fb810f8116c55175ed7018e35eb996fd9471957dabPTO-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-0024…
ADR-0024docs/status/decisions/0024-pc-relative-and-unscaled-agu-addressing.md36dc4f1fbe1714d4eb522f69ccca4216e7a233f55a44cc3f03cb36346911445eLoading 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/SH.PCR.md",
"id": "PTO-SCALAR-SH-PCR",
"instruction_contract": {
"artifact": "spec/evidence/instruction-contract-closure.json",
"mnemonic": "SH.PCR",
"ndf_clause": "PTO-INST-SCALAR-SH-PCR"
},
"mnemonic": "SH.PCR",
"readiness_subjects": [
"ADR-0024",
"ADR-0029",
"ADR-0059",
"ADR-0084"
],
"semantic_tests": [
"PTO-AVS-AGU-SH-PCR-ALIAS-001",
"PTO-AVS-AGU-SH-PCR-BOUND-001",
"PTO-AVS-AGU-SH-PCR-EXEC-001",
"PTO-AVS-AGU-SH-PCR-FAULT-001"
],
"source": "asl/scalar/agu/SH.PCR.asl",
"surface": "scalar",
"tests": [
"PTO-AVS-AGU-SH-PCR-ALIAS-001",
"PTO-AVS-AGU-SH-PCR-BOUND-001",
"PTO-AVS-AGU-SH-PCR-EXEC-001",
"PTO-AVS-AGU-SH-PCR-FAULT-001",
"PTO-AVS-SCALAR-SH-PCR-DECODE-001"
]
}0.58.5 · Release candidate7dc8b7e5b121d2b2499a2273bebff29e2cd868122261217024776f7903bfe29ba454a9eed7fc0e1b8d38892e5e2a999e08f815923244fb7822aa3b5b4df9255d525a9d94261bd32c4fb704f074f36039a50bf7cfasl/scalar/agu/SH.PCR.aslasl/scalar/agu/SH.PCR.aslasl/scalar/agu/SH.PCR.asl