[llvm] [DAGCombiner] Set shift flags during visit. (PR #91239)

[Ulrich Weigand via llvm-commits]

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@@ -85,8 +93,13 @@ define i64 @f7(i64 %val) {
 ; Test another form of f6, which is that produced by InstCombine.
 define i64 @f8(i64 %val) {
 ; CHECK-LABEL: f8:
-; CHECK: lpgfr %r2, %r2
-; CHECK: br %r14
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    sllg %r0, %r2, 32
+; CHECK-NEXT:    srag %r2, %r0, 32
+; CHECK-NEXT:    cgibhe %r0, 0, 0(%r14)
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uweigand wrote:

All the actual changes in the SystemZ tests look to be clear regressions.  It doesn't appear to recognize the "abs" patterns with sign extension and more.

https://github.com/llvm/llvm-project/pull/91239