[clang] ExprConstant - VisitBuiltinCallExpr - rotation folds don't require explicit APInt::urem calls

[RKSimon]

As noticed on #161924 - evaluation of the Builtin::BI__builtin_rotate* intrinsics have an unnecessary Amt.urem() call - APInt::rotl/r handles this for us so we can remove these.

[llvmbot]

Hi!

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[llvmbot]

@llvm/issue-subscribers-good-first-issue

Author: Simon Pilgrim (RKSimon)

As noticed on #161924 - evaluation of the Builtin::BI__builtin_rotate* intrinsics have an unnecessary `Amt.urem()` call - APInt::rotl/r handles this for us so we can remove these.

[rdez13]

Hey @RKSimon, I'd like to work on this issue

[llvmbot]

@llvm/issue-subscribers-clang-frontend

Author: Simon Pilgrim (RKSimon)

As noticed on #161924 - evaluation of the Builtin::BI__builtin_rotate* intrinsics have an unnecessary `Amt.urem()` call - APInt::rotl/r handles this for us so we can remove these.