[llvm] Add known and demanded bits support for zext nneg (PR #70858)

[Nikita Popov via llvm-commits]

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@@ -818,20 +817,19 @@ define i32 @zext_nneg_redundant_and_neg(i8 %a) {
 
 define i64 @zext_nneg_signbit_extract(i32 %a) nounwind {
 ; CHECK-LABEL: @zext_nneg_signbit_extract(
-; CHECK-NEXT:    [[TMP1:%.*]] = lshr i32 [[A:%.*]], 31
-; CHECK-NEXT:    [[C:%.*]] = zext i32 [[TMP1]] to i64
-; CHECK-NEXT:    ret i64 [[C]]
+; CHECK-NEXT:    ret i64 0
 ;
   %b = zext nneg i32 %a to i64
   %c = lshr i64 %b, 31
   ret i64 %c
 }
 
 define i64 @zext_nneg_demanded_constant(i8 %a) nounwind {
+;
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nikic wrote:

Stray semicolon?

https://github.com/llvm/llvm-project/pull/70858