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LOOPcc
Decrements the rcx register by 1. If the rcx register is not 0 and the condition specified by the cc suffix is met, the program counter is updated to the target address.
The following table covers what the source and destinations can be.
| source | destination(s) |
|---|---|
reg (rcx) |
imm |
DO NOT support LOCK
This instruction is only available in 32-bit mode and compatibility mode. In 64-bit mode, LOOPcc is not supported.
The target address must be within a relative offset range of the current instruction. Since rcx is implicitly used as the counter, any manual modification of rcx within the loop body will directly affect the iteration count and may lead to infinite loops if rcx is set to 0.