[llvm-bugs] [Bug 37747] New: Missed optimization opportunity: replacing logical or with bitwise.

[via llvm-bugs]

https://bugs.llvm.org/show_bug.cgi?id=37747

            Bug ID: 37747
           Summary: Missed optimization opportunity: replacing logical or
                    with bitwise.
           Product: clang
           Version: 6.0
          Hardware: PC
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: C++
          Assignee: unassignedclangbugs at nondot.org
          Reporter: denis.yaroshevskij at gmail.com
                CC: dgregor at apple.com, llvm-bugs at lists.llvm.org

std::accumulate(,,,std::bit_or{}) is much faster than
std::accumulate(,,,std::logical_or{}) even though they have the same semantics.

Since there is no branching on the result of the or in accumulate, the compiler
could substitute logical for the bit one. 

QuickBench: http://quick-bench.com/OhizrjUK_8KaF3qa4Bv4LzjEXy8

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