[llvm-bugs] [Bug 25093] New: Missed pattern match for UADDV

[via llvm-bugs]

https://llvm.org/bugs/show_bug.cgi?id=25093

            Bug ID: 25093
           Summary: Missed pattern match for UADDV
           Product: libraries
           Version: trunk
          Hardware: PC
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P
         Component: Backend: AArch64
          Assignee: unassignedbugs at nondot.org
          Reporter: charlesturner7c5 at gmail.com
                CC: llvm-bugs at lists.llvm.org
    Classification: Unclassified

Created attachment 15021
  --> https://llvm.org/bugs/attachment.cgi?id=15021&action=edit
Test case demonstrating missed UADDV.

For the attached testcase, I expect to see an ADDV instruction emitted.

What I actually see is this,


$ llc < reduced4.ll
... <output snipped> ...
test:                                   // @test
        .cfi_startproc
// BB#0:                                // %entry
        ldr             q0, [x0]
        ldr             q1, [x1]
        ushll   v0.8h, v0.8b, #0
        ushll   v1.8h, v1.8b, #0
        usubl   v2.4s, v0.4h, v1.4h
        usubl2  v0.4s, v0.8h, v1.8h
        abs     v0.4s, v0.4s
        abs     v1.4s, v2.4s
        add     v0.4s, v1.4s, v0.4s
        ext     v1.16b, v0.16b, v0.16b, #8
        ext     v1.16b, v0.16b, v1.16b, #8
        add     v0.4s, v0.4s, v1.4s
        dup     v1.4s, v0.s[1]
        add     v0.4s, v0.4s, v1.4s
        fmov    w0, s0
        ret
... <output snipped> ...

The ext -> add sequence should be matched by UADDV.

-- 
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/20151007/5dc25114/attachment-0001.html>