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          [JIT] - X64 - Peephole optimization to possibly skip emitting and reg, -1
          #80468
        
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    | Tagging subscribers to this area: @JulieLeeMSFT, @jakobbotsch, @kunalspathak Issue DetailsA minor change, based off of #79630 The example:         static uint Y(uint i)
        {
            return i & uint.MaxValue;
        }
 | 
              
                    TIHan
  
              
              commented
              
                  
                    Jan 10, 2023 
                  
              
              
            
            
and reg, -1
      | @dotnet/jit-contrib this is ready, pending CI, - @BruceForstall PTAL | 
              
                    BruceForstall
  
              
              approved these changes
              
                  
                    Jan 27, 2023 
                  
              
              
            
            
  
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    area-CodeGen-coreclr
  CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI 
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A minor change, it is similar to the work here -> #79630
The example:
The emitted

and reg, -1can be skipped if we know that thereg's upper 32-bits are zero'ed and that the operation is 32-bits.Overall, there are not that many improvements, but improvements nonetheless.