136
11100B–ATARM–31-Jul-12
SAM4S Series [Preliminary]
11.6.6.2
UMULL, UMAAL, UMLAL
Unsigned Long Multiply, with optional Accumulate, using 32-bit operands and producing a 64-bit
result.
Syntax
op{cond} RdLo, RdHi, Rn, Rm
where:
Operation
These instructions interpret the values from
Rn
and
Rm
as unsigned 32-bit integers.
The
UMULL
instruction:
• Multiplies the two unsigned integers in the first and second operands.
• Writes the least significant 32 bits of the result in
RdLo.
• Writes the most significant 32 bits of the result in
RdHi
.
The
UMAAL
instruction:
• Multiplies the two unsigned 32-bit integers in the first and second operands.
• Adds the unsigned 32-bit integer in
RdHi
to the 64-bit result of the multiplication.
• Adds the unsigned 32-bit integer in
RdLo
to the 64-bit result of the addition.
• Writes the top 32-bits of the result to
RdHi.
• Writes the lower 32-bits of the result to
RdLo
.
The
UMLAL
instruction:
• multiplies the two unsigned integers in the first and second operands.
• Adds the 64-bit result to the 64-bit unsigned integer contained in
RdHi
and
RdLo
.
• Writes the result back to
RdHi
and
RdLo
.
Restrictions
In these instructions:
• do not use SP and do not use PC.
•
RdHi
and
RdLo
must be different registers.
Condition Flags
These instructions do not affect the condition code flags.
Examples
UMULL
R0, R4, R5, R6
; Multiplies R5 and R6, writes the top 32 bits to R4
; and the bottom 32 bits to R0
UMAAL
R3, R6, R2, R7
; Multiplies R2 and R7, adds R6, adds R3, writes the
; top 32 bits to R6, and the bottom 32 bits to R3
UMLAL
R2, R1, R3, R5
; Multiplies R5 and R3, adds R1:R2, writes to R1:R2.
op
is one of:
UMULL
Unsigned Long Multiply.
UMAAL
Unsigned Long Multiply with Accumulate Accumulate.
UMLAL
Unsigned Long Multiply, with Accumulate.
cond
is an optional condition code, see
RdHi, RdLo
are the destination registers. For
UMAAL
,
UMLAL
and
UMLAL
they also hold the
accumulating value.
Rn, Rm
are registers holding the first and second operands.
Содержание SAM4S Series
Страница 44: ...44 11100B ATARM 31 Jul 12 SAM4S Series Preliminary ...
Страница 412: ...412 11100B ATARM 31 Jul 12 SAM4S Series Preliminary ...
Страница 1105: ...1105 11100B ATARM 31 Jul 12 SAM4S Series Preliminary ...
Страница 1142: ...1142 11100B ATARM 31 Jul 12 SAM4S Series Preliminary Figure 43 3 100 ball VFBGA Package Drawing ...
Страница 1143: ...1143 11100B ATARM 31 Jul 12 SAM4S Series Preliminary Figure 43 4 64 lead LQFP Package Drawing ...
Страница 1145: ...1145 11100B ATARM 31 Jul 12 SAM4S Series Preliminary Figure 43 5 64 lead QFN Package Drawing ...