[PATCH] D49958: [MISC]Fix wrong usage of std::equal()

[Hiroshi Inoue via Phabricator via llvm-commits]

inouehrs added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:2919
   // Min/max matching is only viable if all output VTs are the same.
-  if (std::equal(ValueVTs.begin(), ValueVTs.end(), ValueVTs.begin())) {
     EVT VT = ValueVTs[0];
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ikulagin wrote:
> lebedev.ri wrote:
> > This seems to originate from @jmolloy from rL237423.
> maybe it was supposed like this:
> 
> ```
> if (std::equal(ValueVTs.begin(), ValueVTs.end(), ValueVTs.rbegin())) { 
> ```
> iterate from both ends
Comparing from both side may return true for sequences like 1, 2, 1 or 1, 2, 2, 1, although they are not all the same. 


https://reviews.llvm.org/D49958