[llvm-bugs] [Bug 52386] New: [SVE] Don't generate whilelo instruction to enhance the loop condition

[via llvm-bugs]

https://bugs.llvm.org/show_bug.cgi?id=52386

            Bug ID: 52386
           Summary: [SVE] Don't generate whilelo instruction to enhance
                    the loop condition
           Product: libraries
           Version: trunk
          Hardware: PC
                OS: Windows NT
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: Backend: AArch64
          Assignee: unassignedbugs at nondot.org
          Reporter: zhongyunde at huawei.com
                CC: arnaud.degrandmaison at arm.com,
                    llvm-bugs at lists.llvm.org, smithp352 at googlemail.com,
                    Ties.Stuij at arm.com

case from https://reviews.llvm.org/D91077, with this simple case, the newest
clang will not generate whilelo insn for SVE to control the loop condition
(https://godbolt.org/z/hTf5bnhxW, used normal compare insn), while gcc can
(https://godbolt.org/z/xq4vdEYPY, used whilelo insn).

void loop(int N, double *a, double *b) {
  #pragma clang loop vectorize_width(4, scalable)
  for (int i = 0; i < N; i++) {
    a[i] = b[i] + 1.0;
  }
}

-- 
You are receiving this mail because:
You are on the CC list for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-bugs/attachments/20211103/b5693bc6/attachment.html>