vprotb
Vector Packed Rotate Byte
Rotates bytes in XMM register.
Pseudocode Operation
for i in 0..15:
if (imm8 >= 0):
xmm1[i*8+7:i*8] ← ROL(src1[i*8+7:i*8], imm8 & 7)
else:
xmm1[i*8+7:i*8] ← ROR(src1[i*8+7:i*8], (-imm8) & 7)Example
Encoding
Operands
-
dest
128-bit XMM SIMD register -
src1
128-bit XMM SIMD register or Memory operand -
src2
8-bit signed immediate
Related
More in XOP
Reference
Instruction Forms
| Opcode | Instruction | Op/En | 64/32-bit Mode | CPUID | Description |
|---|---|---|---|---|---|
| 8F RXB.09 0.count.0.00 90 /r | VPROTB xmm1, xmm2/mem128, xmm3 | ||||
| 8F RXB.09 1.src.0.00 90 /r | VPROTB xmm1, xmm2, xmm3/mem128 | ||||
| 8F RXB.08 0.1111.0.00 C0 /r ib | VPROTB xmm1, xmm2/mem128, imm8 |
Description
Bytes Rotates each byte of the source as specified by a count operand and writes the result to the corresponding byte of the destination. There are two versions of the instruction, one for each source of the count byte: • VPROTB dest, src, fixed-count • VPROTB dest, src, variable-count For both versions of the instruction, the destination (dest) operand is an XMM register specified by ModRM.reg. The fixed-count version of the instruction rotates each byte of the source (src) the number of bits specified by the immediate fixed-count byte. All bytes are rotated the same amount. The source XMM register or memory location is selected by the ModRM.r/m field. The variable-count version of the instruction rotates each byte of the source the amount specified in the corresponding byte element of the variable-count. Both src and variable-count are configured by XOP.W. • When XOP.W = 0, variable-count is an XMM register specified by XOP.vvvv and src is either an XMM register or a 128-bit memory location specified by ModRM.r/m. • When XOP.W = 1, variable-count is either an XMM register or a 128-bit memory location specified by ModRM.r/m and src is an XMM register specified by XOP.vvvv. When the count value is positive, bits are rotated to the left (toward the more significant bit positions). The bits rotated out left of the most significant bit are rotated back in at the right end (least-significant bit) of the byte. When the count value is negative, bits are rotated to the right (toward the least significant bit positions). The bits rotated to the right out of the least significant bit are rotated back in at the left end (most-significant bit) of the byte. Bits [255:128] of the YMM register that corresponds to the destination are cleared.