[llvm] [InstCombine] Extend folding of aggregate construction to cases when source aggregates are partially available (PR #100828)

[via llvm-commits]

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@@ -213,3 +213,40 @@ exit:
   %res = insertvalue { ptr, i64 } %tmp, i64 %val2, 1
   ret {ptr, i64} %res
 }
+
+; Negative test, %.elt2 is defined in bb %5, it can't be accessed from %3,
+; so we can't add insertvalue to %3.
+define { ptr, i64 } @test5({ ptr, i64 } %0, ptr %1, i1 %.not) {
+; CHECK-LABEL: define { ptr, i64 } @test5(
+; CHECK-SAME: { ptr, i64 } [[TMP0:%.*]], ptr [[TMP1:%.*]], i1 [[DOTNOT:%.*]]) {
+; CHECK-NEXT:    br i1 [[DOTNOT]], label %[[BB3:.*]], label %[[BB4:.*]]
+; CHECK:       [[BB3]]:
+; CHECK-NEXT:    store ptr null, ptr [[TMP1]], align 8
+; CHECK-NEXT:    br label %[[BB5:.*]]
+; CHECK:       [[BB4]]:
+; CHECK-NEXT:    [[DOTELT1:%.*]] = extractvalue { ptr, i64 } [[TMP0]], 0
+; CHECK-NEXT:    br label %[[BB5]]
+; CHECK:       [[BB5]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = phi ptr [ [[DOTELT1]], %[[BB4]] ], [ null, %[[BB3]] ]
+; CHECK-NEXT:    [[DOTELT2:%.*]] = extractvalue { ptr, i64 } [[TMP0]], 1
+; CHECK-NEXT:    [[TMP7:%.*]] = insertvalue { ptr, i64 } zeroinitializer, ptr [[TMP6]], 0
+; CHECK-NEXT:    [[TMP8:%.*]] = insertvalue { ptr, i64 } [[TMP7]], i64 [[DOTELT2]], 1
+; CHECK-NEXT:    ret { ptr, i64 } [[TMP8]]
+;
+  br i1 %.not, label %3, label %4
+
+3:                                                ; preds = %2
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weiguozhi wrote:

done

https://github.com/llvm/llvm-project/pull/100828