ARM Architecture Reference Manual ARMv7-A and ARMv7-R edition

Instruction Details
A8.6.201 STRD (register)
Store Register Dual (register) calculates an address from a base register value and a register offset, and stores
two words from two registers to memory. It can use offset, post-indexed, or pre-indexed addressing. For
information about memory accesses see Memory accesses on page A8-13.
Encoding A1 ARMv5TE*, ARMv6*, ARMv7
STRD ,,[,+/-]{!}
STRD ,,[],+/-
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
cond 0 0 0 P U 0 W 0 Rn Rt (0)(0)(0)(0) 1 1 1 1 Rm
if Rt == ‘1’ then UNDEFINED;
t = UInt(Rt); t2 = t+1; n = UInt(Rn); m = UInt(Rm);
index = (P == ‘1’); add = (U == ‘1’); wback = (P == ‘0’) || (W == ‘1’);
if P == ‘0’ && W == ‘1’ then UNPREDICTABLE;
if t2 == 15 || m == 15 then UNPREDICTABLE;
if wback && (n == 15 || n == t || n == t2) then UNPREDICTABLE;
if ArchVersion() < 6 && wback && m == n then UNPREDICTABLE;
A8-398 Copyright © 1996-1998, 2000, 2004-2008 ARM Limited. All rights reserved. ARM DDI 0406B