Instruction Operation and Execution Notations
Instruction Set
3-2
SPRU733
3.1 Instruction Operation and Execution Notations
Table 3
−
1 explains the symbols used in the instruction descriptions.
Table 3
−
1. Instruction Operation and Execution Notations
Symbol
Meaning
abs(x)
Absolute value of x
and
Bitwise AND
−
a
Perform 2s-complement subtraction using the addressing mode defined by the AMR
+a
Perform 2s-complement addition using the addressing mode defined by the AMR
b
i
Select bit i of source/destination b
bit_count
Count the number of bits that are 1 in a specified byte
bit_reverse
Reverse the order of bits in a 32-bit register
byte0
8-bit value in the least-significant byte position in 32-bit register (bits 0-7)
byte1
8-bit value in the next to least-significant byte position in 32-bit register (bits 8-15)
byte2
8-bit value in the next to most-significant byte position in 32-bit register (bits 16-23)
byte3
8-bit value in the most-significant byte position in 32-bit register (bits 24-31)
bv2
Bit vector of two flags for s2 or u2 data type
bv4
Bit vector of four flags for s4 or u4 data type
b
y..z
Selection of bits y through z of bit string b
cond
Check for either
creg
equal to 0 or
creg
not equal to 0
creg
3-bit field specifying a conditional register, see section 3.6
cstn
n-bit constant field (for example, cst5)
dint
64-bit integer value (two registers)
dp
Double-precision floating-point register value
dp(x)
Convert x to dp
dst_h
or
dst_o
msb32 of
dst
(placed in odd-numbered register of 64-bit register pair)
dst_l
or
dst_e
lsb32 of
dst
(placed in even-numbered register of a 64-bit register pair)
dws4
Four packed signed 16-bit integers in a 64-bit register pair
dwu4
Four packed unsigned 16-bit integers in a 64-bit register pair