Instruction nullification (in HP PA)
Any register-register or any branch instruction can specify whether the following instruction should be executed
- There is enough room in encoding of reg-reg instructions
Similar to conditional moves but allows to skip over instructions that could produce exceptions
- Compute result of S1 in Rs1
Compute condition to skip next instruction or not (could be Rs1, the result of the previous instruction)
Rres set to Rs1 unless skipped (thus can avoid some exceptions)