[llvm] 535c2da - [SCEV] Add range test with phi and division.

[Florian Hahn via llvm-commits]

Author: Florian Hahn
Date: 2022-11-21T19:58:43Z
New Revision: 535c2da58dd2469dc8b8610443b51e5b10867074

URL: https://github.com/llvm/llvm-project/commit/535c2da58dd2469dc8b8610443b51e5b10867074
DIFF: https://github.com/llvm/llvm-project/commit/535c2da58dd2469dc8b8610443b51e5b10867074.diff

LOG: [SCEV] Add range test with phi and division.

Extra test coverage for D130728.

Added: 
    

Modified: 
    llvm/test/Analysis/ScalarEvolution/ranges.ll

Removed: 
    


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diff  --git a/llvm/test/Analysis/ScalarEvolution/ranges.ll b/llvm/test/Analysis/ScalarEvolution/ranges.ll
index 00480a28ff722..f5583d091f148 100644
--- 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
+}