[PATCH] D78929: [AIX][XCOFF]emit extern linkage for the llvm intrinsic symbol

Jason Liu via Phabricator via llvm-commits llvm-commits at lists.llvm.org
Tue Apr 28 14:34:38 PDT 2020


jasonliu added inline comments.


================
Comment at: llvm/include/llvm/MC/MCContext.h:105
+    /// linkage.
+    std::vector<MCSymbol *> XCOFFIntrinsicSymbols;
+    using XCOFFIntrinsicSym_iterator = std::vector<MCSymbol *>::iterator;
----------------
DiggerLin wrote:
> jasonliu wrote:
> > Just a general comment on the data structure that's using here.
> > Have we thought about using using a SmallPtrSet so that you don't need to worry about inserting the duplicated value into the vector?
> /// SmallPtrSet - This class implements a set which is optimized for holding
>  /// SmallSize or less elements.  This internally rounds up SmallSize to the next
>  /// power of two if it is not already a power of two.  See the comments above
>  /// SmallPtrSetImplBase for details of the algorithm.
>  template<class PtrType, unsigned SmallSize>
>  class SmallPtrSet : public SmallPtrSetImpl<PtrType> {
>    // In small mode SmallPtrSet uses linear search for the elements, so it is
>    // not a good idea to choose this value too high. You may consider using a
>    // DenseSet<> instead if you expect many elements in the set.
>    static_assert(SmallSize <= 32, "SmallSize should be small");
> 
> There are hundreds llvm intrinsic function. I will use std::set   
There are hundreds of llvm intrinsic functions. But are you expecting every compilation will contain hundreds of llvm intrinsic functions? I would say most of the time, you would see those less than 8intrinsic functions in one compilation unit , except for some very heavy mathematic case. 


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D78929/new/

https://reviews.llvm.org/D78929





More information about the llvm-commits mailing list