Imported Upstream version 5.18.0.179

Former-commit-id: 67aa10e65b237e1c4537630979ee99ebe1374215

external/llvm/test/Analysis/ScalarEvolution/2008-07-29-SGTTripCount.ll

@@ -0,0 +1,28 @@
+; RUN: opt < %s -analyze -scalar-evolution \
+; RUN:   -scalar-evolution-max-iterations=0 | FileCheck %s
+; PR2607
+
+define i32 @_Z1aj(i32 %j) nounwind  {
+entry:
+	icmp sgt i32 0, %j		; <i1>:0 [#uses=1]
+	br i1 %0, label %bb.preheader, label %return
+
+bb.preheader:		; preds = %entry
+	br label %bb
+
+bb:		; preds = %bb, %bb.preheader
+	%i.01 = phi i32 [ %1, %bb ], [ 0, %bb.preheader ]		; <i32> [#uses=1]
+	add i32 %i.01, -1		; <i32>:1 [#uses=3]
+	icmp sgt i32 %1, %j		; <i1>:2 [#uses=1]
+	br i1 %2, label %bb, label %return.loopexit
+
+return.loopexit:		; preds = %bb
+	br label %return
+
+return:		; preds = %return.loopexit, %entry
+	%i.0.lcssa = phi i32 [ 0, %entry ], [ %1, %return.loopexit ]		; <i32> [#uses=1]
+	ret i32 %i.0.lcssa
+}
+
+; CHECK: backedge-taken count is (-1 + (-1 * %j))
+