## Orc Opcodes

Orc Opcodes — Description of Opcodes

## Orc Opcodes

Opcodes only work with variables of a particular size. In the table below, destination and source indicate the size of the destination and source operands, in bytes. In general, opcodes have a suffix indicating the sizes, "b" for 1-byte operations, "w" for 2-byte operations, and "l" for 4-byte operations. If the source and destination have different sizes, the source size suffix is listed first, then the destination suffix. For example, converting a 1-byte variable to 2-byte can be performed using the "convsbw" opcode.

Signed, unsigned, and saturating operations are indicated by the letters "s", "u", and "s". If signed or unsigned is not indicated, it generally means that the signedness is not relevant to the definition of the opcode, and that the operation on signed or unsigned values will give the same result.

The "select" opcodes divide the bits in the source value into two halves. For "select0", the half that is first in memory order is selected, and the latter half for "select1". In other words, "convwb" is the same as "select0wb" on little-endian systems, and "select1wb" on big-endian systems.

The "merge" opcodes take two values and put them together in memory order.

Accumulating opcodes require an accumulator variable as the destination. Accumulating opcodes start with "acc". These opcodes sum the source values over the entire array, and can be read from the OrcExecutor structure after an execution of an Orc program.

Shift opcodes only work with constants or parameters as the second source value.

For more precise understanding of operations, it is recommended to compile a program for the C target and examine the resulting C source code.

Table 1. Table of Opcodes

opcode | destination | source 1 | source 2 | description | pseudo code
--- | --- | --- | --- | --- | ---
absb | 1 | 1 |  | absolute value | (a < 0) ? -a : a
addb | 1 | 1 | 1 | add | a + b
addssb | 1 | 1 | 1 | add with signed saturate | clamp(a + b)
addusb | 1 | 1 | 1 | add with unsigned saturate | clamp(a + b)
andb | 1 | 1 | 1 | bitwise AND | a & b
andnb | 1 | 1 | 1 | bitwise AND NOT | a & (~b)
avgsb | 1 | 1 | 1 | signed average | (a + b + 1)>>1
avgub | 1 | 1 | 1 | unsigned average | (a + b + 1)>>1
cmpeqb | 1 | 1 | 1 | compare equal | (a == b) ? (~0) : 0
cmpgtsb | 1 | 1 | 1 | compare greater than | (a > b) ? (~0) : 0
copyb | 1 | 1 |  | copy | a
maxsb | 1 | 1 | 1 | signed maximum | (a > b) ? a : b
maxub | 1 | 1 | 1 | unsigned maximum | (a > b) ? a : b
minsb | 1 | 1 | 1 | signed minimum | (a < b) ? a : b
minub | 1 | 1 | 1 | unsigned minimum | (a < b) ? a : b
mullb | 1 | 1 | 1 | low bits of multiply | a * b
mulhsb | 1 | 1 | 1 | high bits of signed multiply | (a * b) >> 8
mulhub | 1 | 1 | 1 | high bits of unsigned multiply | (a * b) >> 8
orb | 1 | 1 | 1 | bitwise or | a | b
shlb | 1 | 1 | 1 | shift left | a << b
shrsb | 1 | 1 | 1 | signed shift right | a >> b
shrub | 1 | 1 | 1 | unsigned shift right | a >> b
signb | 1 | 1 |  | sign | sign(a)
subb | 1 | 1 | 1 | subtract | a - b
subssb | 1 | 1 | 1 | subtract with signed saturate | clamp(a - b)
subusb | 1 | 1 | 1 | subtract with unsigned saturate | clamp(a - b)
xorb | 1 | 1 | 1 | bitwise XOR | a ^ b
absw | 2 | 2 |  | absolute value | (a < 0) ? -a : a
addw | 2 | 2 | 2 | add | a + b
addssw | 2 | 2 | 2 | add with signed saturate | clamp(a + b)
addusw | 2 | 2 | 2 | add with unsigned saturate | clamp(a + b)
andw | 2 | 2 | 2 | bitwise AND | a & b
andnw | 2 | 2 | 2 | bitwise AND NOT | a & (~b)
avgsw | 2 | 2 | 2 | signed average | (a + b + 1)>>1
avguw | 2 | 2 | 2 | unsigned average | (a + b + 1)>>1
cmpeqw | 2 | 2 | 2 | compare equal | (a == b) ? (~0) : 0
cmpgtsw | 2 | 2 | 2 | compare greater than | (a > b) ? (~0) : 0
copyw | 2 | 2 |  | copy | a
maxsw | 2 | 2 | 2 | signed maximum | (a > b) ? a : b
maxuw | 2 | 2 | 2 | unsigned maximum | (a > b) ? a : b
minsw | 2 | 2 | 2 | signed minimum | (a < b) ? a : b
minuw | 2 | 2 | 2 | unsigned minimum | (a < b) ? a : b
mullw | 2 | 2 | 2 | low bits of multiply | a * b
mulhsw | 2 | 2 | 2 | high bits of signed multiply | (a * b) >> 8
mulhuw | 2 | 2 | 2 | high bits of unsigned multiply | (a * b) >> 8
orw | 2 | 2 | 2 | bitwise or | a | b
shlw | 2 | 2 | 2 | shift left | a << b
shrsw | 2 | 2 | 2 | signed shift right | a >> b
shruw | 2 | 2 | 2 | unsigned shift right | a >> b
signw | 2 | 2 |  | sign | sign(a)
subw | 2 | 2 | 2 | subtract | a - b
subssw | 2 | 2 | 2 | subtract with signed saturate | clamp(a - b)
subusw | 2 | 2 | 2 | subtract with unsigned saturate | clamp(a - b)
xorw | 2 | 2 | 2 | bitwise XOR | a ^ b
absl | 4 | 4 |  | absolute value | (a < 0) ? -a : a
addl | 4 | 4 | 4 | add | a + b
addssl | 4 | 4 | 4 | add with signed saturate | clamp(a + b)
addusl | 4 | 4 | 4 | add with unsigned saturate | clamp(a + b)
andl | 4 | 4 | 4 | bitwise AND | a & b
andnl | 4 | 4 | 4 | bitwise AND NOT | a & (~b)
avgsl | 4 | 4 | 4 | signed average | (a + b + 1)>>1
avgul | 4 | 4 | 4 | unsigned average | (a + b + 1)>>1
cmpeql | 4 | 4 | 4 | compare equal | (a == b) ? (~0) : 0
cmpgtsl | 4 | 4 | 4 | compare greater than | (a > b) ? (~0) : 0
copyl | 4 | 4 |  | copy | a
maxsl | 4 | 4 | 4 | signed maximum | (a > b) ? a : b
maxul | 4 | 4 | 4 | unsigned maximum | (a > b) ? a : b
minsl | 4 | 4 | 4 | signed minimum | (a < b) ? a : b
minul | 4 | 4 | 4 | unsigned minimum | (a < b) ? a : b
mulll | 4 | 4 | 4 | low bits of multiply | a * b
mulhsl | 4 | 4 | 4 | high bits of signed multiply | (a * b) >> 8
mulhul | 4 | 4 | 4 | high bits of unsigned multiply | (a * b) >> 8
orl | 4 | 4 | 4 | bitwise or | a | b
shll | 4 | 4 | 4 | shift left | a << b
shrsl | 4 | 4 | 4 | signed shift right | a >> b
shrul | 4 | 4 | 4 | unsigned shift right | a >> b
signl | 4 | 4 |  | sign | sign(a)
subl | 4 | 4 | 4 | subtract | a - b
subssl | 4 | 4 | 4 | subtract with signed saturate | clamp(a - b)
subusl | 4 | 4 | 4 | subtract with unsigned saturate | clamp(a - b)
xorl | 4 | 4 | 4 | bitwise XOR | a ^ b
convsbw | 2 | 1 |  | convert signed | a
convubw | 2 | 1 |  | convert unsigned | a
convswl | 4 | 2 |  | convert signed | a
convuwl | 4 | 2 |  | convert unsigned | a
convwb | 1 | 2 |  | convert | a
convssswb | 1 | 2 |  | convert signed to signed with saturation | clamp(a)
convsuswb | 1 | 2 |  | convert signed to unsigned with saturation | clamp(a)
convusswb | 1 | 2 |  | convert unsigned to signed with saturation | clamp(a)
convuuswb | 1 | 2 |  | convert unsigned to unsigned with saturation | clamp(a)
convlw | 2 | 4 |  | convert | a
convssslw | 2 | 4 |  | convert signed to unsigned with saturation | clamp(a)
convsuslw | 2 | 4 |  | convert signed to signed with saturation | clamp(a)
convusslw | 2 | 4 |  | convert unsigned to unsigned with saturation | clamp(a)
convuuslw | 2 | 4 |  | convert unsigned to signed with saturation | clamp(a)
mulsbw | 2 | 1 | 1 | multiply signed | a * b
mulubw | 2 | 1 | 1 | multiply unsigned | a * b
mulswl | 4 | 2 | 2 | multiply signed | a * b
muluwl | 4 | 2 | 2 | multiply unsigned | a * b
accw | 2 | 2 |  | accumulate | += a
accl | 4 | 4 |  | accumulate | += a
accsadubl | 4 | 1 | 1 | accumulate absolute difference | += abs(a - b)
swapw | 2 | 2 |  | endianness swap | special
swapl | 4 | 4 |  | endianness swap | special
select0wb | 1 | 2 |  | select first half | special
select1wb | 1 | 2 |  | select second half | special
select0lw | 2 | 4 |  | select first half | special
select1lw | 2 | 4 |  | select second half | special
mergewl | 4 | 2 | 2 | merge halves | special
mergebw | 2 | 1 | 1 | merge halves | special

In the pseudo code of the above table, abs() indicates absolute value, clamp() indicates that any values outside the destination range are set to the nearest value in the destination range, and sign() evaluates to -1 for values less than 0, 1 for values greater than 0, and 0 for 0.

## Rule Coverage

The values for shift operations are not correct in this table.

Table 2. Table of Opcode Rule Coverage

opcode name | sse | mmx | altivec | arm
--- | --- | --- | --- | ---
absb | yes | yes | no | no
addb | yes | yes | yes | no
addssb | yes | yes | yes | no
addusb | yes | yes | yes | no
andb | yes | yes | yes | no
andnb | yes | yes | yes | no
avgsb | yes | yes | yes | no
avgub | yes | yes | yes | no
cmpeqb | yes | yes | yes | no
cmpgtsb | yes | yes | yes | no
copyb | yes | yes | yes | no
maxsb | yes | yes | yes | no
maxub | yes | yes | yes | no
minsb | yes | yes | yes | no
minub | yes | yes | yes | no
mullb | no | no | yes | no
mulhsb | no | no | yes | no
mulhub | no | no | yes | no
orb | yes | yes | yes | no
shlb | no | no | no | no
shrsb | no | no | no | no
shrub | no | no | no | no
signb | yes | yes | yes | no
subb | yes | yes | yes | no
subssb | yes | yes | yes | no
subusb | yes | yes | yes | no
xorb | yes | yes | yes | no
absw | yes | yes | no | no
addw | yes | yes | yes | yes
addssw | yes | yes | yes | no
addusw | yes | yes | yes | no
andw | yes | yes | yes | no
andnw | yes | yes | yes | no
avgsw | yes | yes | yes | no
avguw | yes | yes | yes | no
cmpeqw | yes | yes | yes | no
cmpgtsw | yes | yes | yes | no
copyw | yes | yes | yes | no
maxsw | yes | yes | yes | no
maxuw | yes | yes | yes | no
minsw | yes | yes | yes | no
minuw | yes | yes | yes | no
mullw | yes | yes | yes | yes
mulhsw | yes | yes | yes | no
mulhuw | yes | yes | yes | no
orw | yes | yes | yes | no
shlw | no | no | no | no
shrsw | no | no | no | yes
shruw | no | no | no | no
signw | yes | yes | yes | no
subw | yes | yes | yes | yes
subssw | yes | yes | yes | no
subusw | yes | yes | yes | no
xorw | yes | yes | yes | no
absl | yes | yes | no | no
addl | yes | yes | yes | no
addssl | no | no | yes | no
addusl | no | no | yes | no
andl | yes | yes | yes | no
andnl | yes | yes | yes | no
avgsl | no | no | yes | no
avgul | no | no | yes | no
cmpeql | yes | yes | yes | no
cmpgtsl | yes | yes | yes | no
copyl | yes | yes | yes | no
maxsl | yes | yes | yes | no
maxul | yes | yes | yes | no
minsl | yes | yes | yes | no
minul | yes | yes | yes | no
mulll | no | no | no | no
mulhsl | no | no | no | no
mulhul | no | no | no | no
orl | yes | yes | yes | no
shll | no | no | no | no
shrsl | no | no | no | no
shrul | no | no | no | no
signl | yes | yes | yes | no
subl | yes | yes | yes | no
subssl | no | no | yes | no
subusl | no | no | yes | no
xorl | yes | yes | yes | no
convsbw | yes | yes | yes | no
convubw | yes | yes | yes | no
convswl | yes | yes | yes | no
convuwl | yes | yes | yes | no
convwb | yes | yes | yes | no
convssswb | yes | yes | yes | no
convsuswb | yes | yes | yes | no
convusswb | no | no | no | no
convuuswb | no | no | yes | no
convlw | yes | yes | yes | no
convssslw | yes | yes | yes | no
convsuslw | no | no | yes | no
convusslw | no | no | no | no
convuuslw | no | no | yes | no
mulsbw | no | no | yes | no
mulubw | no | no | yes | no
mulswl | yes | yes | yes | no
muluwl | no | no | yes | no
accw | yes | yes | yes | no
accl | yes | yes | yes | no
accsadubl | yes | yes | yes | no
swapw | yes | yes | no | no
swapl | yes | yes | no | no
select0wb | yes | yes | no | no
select1wb | yes | yes | no | no
select0lw | yes | yes | no | no
select1lw | yes | yes | no | no
mergewl | yes | yes | no | no
mergebw | yes | yes | no | no