Intel® IXP42X Product Line of Network Processors and IXC1100 Control Plane Processor
September 2006 DM
Order Number: 252480-006US 151
Intel XScale® Processor—Intel® IXP42X product line and IXC1100 control plane processors
The MAR instruction moves the value in register RdLo to bits[31:0] of the 40-bit
accumulator (acc0) and moves bits[7:0] of the value in register RdHi into bits[39:32]
of acc0.
The instruction is only executed if the condition specified in the instruction matches the
condition code status.
This instruction executes in any processor mode.
The MRA instruction moves the 40-bit accumulator value (acc0) into two registers.
Bits[31:0] of the value in acc0 are moved into the register RdLo. Bits[39:32] of the
value in acc0 are sign extended to 32 bits and moved into the register RdHi.
The instruction is only executed if the condition specified in the instruction matches the
condition code status.
Table 67. MAR{<cond>} acc0, RdLo, RdHi
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9876543210
cond 11000100 RdHi RdLo 000000000000
Operation: if ConditionPassed(<cond>) then
acc0[39:32] = RdHi[7:0]
acc0[31:0] = RdLo[31:0]
Exceptions:none
Qualifiers Condition Code
No condition code flags are updated
Notes: Instruction timings can be found in
“Multiply Instruction Timings” on page 163
Specifying R15 as either RdHi or RdLo has unpredictable results.
Table 68. MRA{<cond>} RdLo, RdHi, acc0
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9876543210
cond 11000101 RdHi RdLo 000000000000
Operation: if ConditionPassed(<cond>) then
RdHi[31:0] = sign_extend(acc0[39:32])
RdLo[31:0] = acc0[31:0]
Exceptions:none
Qualifiers Condition Code
No condition code flags are updated
Notes: Instruction timings can be found in
“Multiply Instruction Timings” on page 163
Specifying the same register for RdHi and RdLo has unpredictable
results.
Specifying R15 as either RdHi or RdLo has unpredictable results.