[SCEV] Add range test with phi and division.

Extra test coverage for D130728.
llvm · Nov 21, 2022 · 535c2da · 535c2da
1 parent 71b2ff7
commit 535c2da
Showing 1 changed file with 21 additions and 0 deletions.
diff --git a/llvm/test/Analysis/ScalarEvolution/ranges.ll b/llvm/test/Analysis/ScalarEvolution/ranges.ll
@@ -103,3 +103,24 @@ define i64 @zext(i8 %a) {
   call void @llvm.assume(i1 %pos)
   ret i64 %res
 }
+
+define i32 @phi_div() {
+; CHECK-LABEL: 'phi_div'
+; CHECK-NEXT:  Classifying expressions for: @phi_div
+; CHECK-NEXT:    %range.1 = phi i32 [ 0, %entry ], [ %shr, %loop ]
+; CHECK-NEXT:    --> %range.1 U: [0,1) S: [0,1) Exits: <<Unknown>> LoopDispositions: { %loop: Variant }
+; CHECK-NEXT:    %shr = lshr i32 %range.1, 1
+; CHECK-NEXT:    --> (%range.1 /u 2) U: [0,1) S: [0,1) Exits: <<Unknown>> LoopDispositions: { %loop: Variant }
+; CHECK-NEXT:  Determining loop execution counts for: @phi_div
+; CHECK-NEXT:  Loop %loop: <multiple exits> Unpredictable backedge-taken count.
+; CHECK-NEXT:  Loop %loop: Unpredictable max backedge-taken count.
+; CHECK-NEXT:  Loop %loop: Unpredictable predicated backedge-taken count.
+;
+entry:
+  br label %loop
+
+loop:
+  %range.1 = phi i32 [ 0, %entry ], [ %shr, %loop ]
+  %shr = lshr i32 %range.1, 1
+  br label %loop
+}