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PMAXSB
Compares the signed 8-bit integer values of the source and destination operands and stores the maximum of the two in the destination.
The table below covers what the source and destinations can be.
| source | destination(s) |
|---|---|
| r8 | r8 |
| m1 | r8 |
| r8 | m1 |
| #I | m1 |
DO NOT support LOCK
This instruction is available only in 64-bit mode or compatibility mode. It is not supported in 32-bit protected mode.
The instruction operates on signed integers; using it for unsigned comparisons will yield incorrect results. Ensure that the data in the r8 or m1 operands is treated as a signed i8 to avoid logical errors in maximum value determination.