[LICM] Add test show missed promotion due to AAInfo merging (NFC)

Author: brunodf-snps

llvm/test/Transforms/LICM/variant-aainfo.ll

@@ -0,0 +1,59 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
+; RUN: opt < %s -S -passes=licm | FileCheck %s
+
+; See https://discourse.llvm.org/t/rfc-dont-merge-memory-locations-in-aliassettracker/73336
+; pairwise TBAA indicates NoAlias of load/store ptr at %s with store i32 at %0
+; yet LICM fails to promote load/store ptr %s out of the loop
+
+define void @_Z4testP1S(ptr %s) {
+; CHECK-LABEL: define void @_Z4testP1S(
+; CHECK-SAME: ptr [[S:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br label [[FOR_BODY:%.*]]
+; CHECK:       for.cond.cleanup:
+; CHECK-NEXT:    ret void
+; CHECK:       for.body:
+; CHECK-NEXT:    [[I_05:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[INC:%.*]], [[FOR_BODY]] ]
+; CHECK-NEXT:    [[TMP0:%.*]] = load ptr, ptr [[S]], align 4, !tbaa [[TBAA0:![0-9]+]]
+; CHECK-NEXT:    store i32 [[I_05]], ptr [[TMP0]], align 4, !tbaa [[TBAA5:![0-9]+]]
+; CHECK-NEXT:    [[ADD_PTR_I:%.*]] = getelementptr inbounds i32, ptr [[TMP0]], i32 1
+; CHECK-NEXT:    store ptr [[ADD_PTR_I]], ptr [[S]], align 4, !tbaa [[TBAA7:![0-9]+]]
+; CHECK-NEXT:    [[INC]] = add nuw nsw i32 [[I_05]], 1
+; CHECK-NEXT:    [[EXITCOND_NOT:%.*]] = icmp eq i32 [[INC]], 100
+; CHECK-NEXT:    br i1 [[EXITCOND_NOT]], label [[FOR_COND_CLEANUP:%.*]], label [[FOR_BODY]]
+;
+entry:
+  br label %for.body
+
+for.cond.cleanup:                                 ; preds = %for.body
+  ret void
+
+for.body:                                         ; preds = %entry, %for.body
+  %i.05 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
+  %0 = load ptr, ptr %s, align 4, !tbaa !0
+  store i32 %i.05, ptr %0, align 4, !tbaa !5
+  %add.ptr.i = getelementptr inbounds i32, ptr %0, i32 1
+  store ptr %add.ptr.i, ptr %s, align 4, !tbaa !7
+  %inc = add nuw nsw i32 %i.05, 1
+  %exitcond.not = icmp eq i32 %inc, 100
+  br i1 %exitcond.not, label %for.cond.cleanup, label %for.body
+}
+
+!0 = !{!1, !2, i64 0}
+!1 = !{!"_ZTS1S", !2, i64 0}
+!2 = !{!"any pointer", !3, i64 0}
+!3 = !{!"omnipotent char", !4, i64 0}
+!4 = !{!"Simple C++ TBAA"}
+!5 = !{!6, !6, i64 0}
+!6 = !{!"int", !3, i64 0}
+!7 = !{!2, !2, i64 0}
+;.
+; CHECK: [[TBAA0]] = !{[[META1:![0-9]+]], [[META2:![0-9]+]], i64 0}
+; CHECK: [[META1]] = !{!"_ZTS1S", [[META2]], i64 0}
+; CHECK: [[META2]] = !{!"any pointer", [[META3:![0-9]+]], i64 0}
+; CHECK: [[META3]] = !{!"omnipotent char", [[META4:![0-9]+]], i64 0}
+; CHECK: [[META4]] = !{!"Simple C++ TBAA"}
+; CHECK: [[TBAA5]] = !{[[META6:![0-9]+]], [[META6]], i64 0}
+; CHECK: [[META6]] = !{!"int", [[META3]], i64 0}
+; CHECK: [[TBAA7]] = !{[[META2]], [[META2]], i64 0}
+;.