Encoding:

Format:

SD rt, offset(base)

Purpose:

Store Doubleword

To store a doubleword to memory.

Description:

 memory[GPR[base] + offset] = GPR[rt]

The 64-bit doubleword in GPR rt is stored in memory at the location specified by the aligned effective address. The

16-bit signed offset is added to the contents of GPR base to form the effective address.

Restrictions:

Pre-release 6: The effective address must be naturally-aligned. If any of the 3 least-significant bits of the effective address is non-zero, an Address Error exception occurs.

Release 6 allows hardware to provide address misalignment support in lieu of requiring natural alignment.

Note: The pseudocode is not completely adapted for Release 6 misalignment support as the handling is implementation dependent.

Operation:

vAddr = sign_extend(offset) + GPR[base]
(pAddr, CCA) = AddressTranslation (vAddr, DATA, STORE)
datadoubleword = GPR[rt]
StoreMemory (CCA, DOUBLEWORD, datadoubleword, pAddr, vAddr, DATA)

Exceptions:

TLB Refill, TLB Invalid, TLB Modified, Address Error, Reserved Instruction, Watch