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Max (goldstein@im-in.space)'s status on Sunday, 10-Nov-2024 06:54:27 JST Max

MSVC is the only compiler to apply optimizations based on restrict on local variables, which it immediately remediates by generating a lot more stack shuffling than GCC or Clang: https://godbolt.org/z/954dGcabx
In conversation about 17 days ago from im-in.space permalink
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  Compiler Explorer - C
  
  from Matt Godbolt
  
  void black_box(int); int* gimme_a_pointer(void); int check(int* a) { int* restrict b = gimme_a_pointer(); int val = *b; black_box(val); *a = 42; return *b; }
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  pinskia (pinskia@hachyderm.io)'s status on Sunday, 10-Nov-2024 06:54:24 JST pinskia
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  @goldstein This is https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89479 .
  In conversation about 17 days ago permalink
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    89479 – __restrict on a pointer ignored when disambiguating against a call
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  Max (goldstein@im-in.space)'s status on Sunday, 10-Nov-2024 06:54:26 JST Max
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  GCC (but not Clang) also seems to ignore restrict on a func param, for a reason I can’t comprehend since PARM_NOALIAS shows up in pass details: https://godbolt.org/z/Yr475sn7z
  In conversation about 17 days ago permalink
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  1. Domain not in remote thumbnail source whitelist: raw.githubusercontent.com
    
    Compiler Explorer - C
    
    from Matt Godbolt
    
    void black_box(int); int* gimme_a_pointer(void); int check(int* a,int *restrict b) { int val = *b; black_box(val); *a = 42; return *b; }
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  pinskia (pinskia@hachyderm.io)'s status on Sunday, 10-Nov-2024 06:54:31 JST pinskia
  in reply to
  
  @goldstein This is https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60712 and https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81786.
  In conversation about 17 days ago permalink
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    60712 – "restrict" qualifier ignored on local variable
  2. No result found on File_thumbnail lookup.
    
    81786 – local restricted pointer can be relied on in alias analysis

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