[llvm-bugs] [Bug 41495] New: Suboptimal codegen: (x << 1) | 1 results in LEA+ADD while could be just LEA

[via llvm-bugs]

https://bugs.llvm.org/show_bug.cgi?id=41495

            Bug ID: 41495
           Summary: Suboptimal codegen: (x << 1) | 1 results in LEA+ADD
                    while could be just LEA
           Product: libraries
           Version: trunk
          Hardware: PC
                OS: All
            Status: NEW
          Keywords: code-quality
          Severity: normal
          Priority: P
         Component: Backend: X86
          Assignee: unassignedbugs at nondot.org
          Reporter: nok.raven at gmail.com
                CC: craig.topper at gmail.com, llvm-bugs at lists.llvm.org,
                    llvm-dev at redking.me.uk, spatel+llvm at rotateright.com

int foo(int x)
{
    return (x << 1) | 1;
}

GCC/ICC:
  lea eax, [rdi+1+rdi]

Clang:
  lea eax, [rdi+rdi]
  add eax, 1

Interestingly enough for 32bit target Clang produces:
  mov eax, dword ptr [esp + 4]
  lea eax, [eax+eax+1]

https://godbolt.org/z/PpiqqU

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