[llvm-bugs] [Bug 44754] New: [InstCombine] ashr+and+icmp not simplified

[via llvm-bugs]

https://bugs.llvm.org/show_bug.cgi?id=44754

            Bug ID: 44754
           Summary: [InstCombine] ashr+and+icmp not simplified
           Product: libraries
           Version: trunk
          Hardware: PC
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: Scalar Optimizations
          Assignee: unassignedbugs at nondot.org
          Reporter: nikita.ppv at gmail.com
                CC: llvm-bugs at lists.llvm.org

define i1 @foo(i32 %a) {
  %ashr = ashr i32 %a, 5
  %and = and i32 %ashr, -2
  %cmp = icmp slt i32 %and, 1
  ret i1 %cmp
}

is not simplified to

define i1 @foo(i32 %a) {
  %and2 = and i32 %a, -64
  %cmp = icmp slt i32 %and2, 32
  ret i1 %cmp
}

but could be (https://rise4fun.com/Alive/FkZq).

Encountered this as fallout from a worklist order change in
test/Transforms/InstCombine/pr17827.ll.

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