[PATCH] D49273: [InstCombine] Expand the simplification of pow() into exp2()

[Evandro Menezes via Phabricator via llvm-commits]

evandro added a comment.

@rnk has kindly reduced the issue to:

  target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"                              
  target triple = "x86_64-unknown-windows-msvc19.11.0"                                     
  @a = dso_local global double 0.000000e+00, align 8                                       
  define dso_local double @b() {                                                           
  entry:                                                                                   
    %0 = load double, double* @a, align 8                                                  
    %call = call double @pow(double 2.000000e+00, double %0)                               
    ret double %call                                                                       
  }                                                                                        
  declare dso_local double @pow(double, double)  

I added a test to cover this case and variations of it on Windows.


https://reviews.llvm.org/D49273