From e9d4bb43f8432c58d87ff6c725f4b92db084d650 Mon Sep 17 00:00:00 2001
From: Philip Reames <listmail@philipreames.com>
Date: Fri, 23 Jul 2021 17:19:34 -0700
Subject: [PATCH] [tests] SCEV trip count w/ neg step and varying rhs

---
 .../trip-count-negative-stride.ll             | 81 +++++++++++++++++++
 1 file changed, 81 insertions(+)

diff --git a/llvm/test/Analysis/ScalarEvolution/trip-count-negative-stride.ll b/llvm/test/Analysis/ScalarEvolution/trip-count-negative-stride.ll
index adc6dcc3fa12..aeeafdceb3ef 100644
--- a/llvm/test/Analysis/ScalarEvolution/trip-count-negative-stride.ll
+++ b/llvm/test/Analysis/ScalarEvolution/trip-count-negative-stride.ll
@@ -206,6 +206,47 @@ for.end:                                          ; preds = %for.body, %entry
   ret void
 }
 
+; CHECK-LABEL: Determining loop execution counts for: @ult_129_varying_rhs
+; CHECK: Loop %for.body: Unpredictable backedge-taken count.
+; CHECK: Loop %for.body: Unpredictable max backedge-taken count
+
+define void @ult_129_varying_rhs(i8* %n_p) {
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %entry, %for.body
+  %i.05 = phi i8 [ %add, %for.body ], [ 0, %entry ]
+  %add = add nuw i8 %i.05, 129
+  %n = load i8, i8* %n_p
+  %cmp = icmp ult i8 %add, %n
+  br i1 %cmp, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.body, %entry
+  ret void
+}
+
+; CHECK-LABEL: Determining loop execution counts for: @ult_symbolic_varying_rhs
+; CHECK: Loop %for.body: Unpredictable backedge-taken count.
+; CHECK: Loop %for.body: Unpredictable max backedge-taken count
+
+define void @ult_symbolic_varying_rhs(i8* %n_p, i8 %step) {
+entry:
+  %assume = icmp ult i8 128, %step
+  call void @llvm.assume(i1 %assume)
+  br label %for.body
+
+for.body:                                         ; preds = %entry, %for.body
+  %i.05 = phi i8 [ %add, %for.body ], [ 0, %entry ]
+  %add = add nuw i8 %i.05, %step
+  %n = load i8, i8* %n_p
+  %cmp = icmp ult i8 %add, %n
+  br i1 %cmp, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.body, %entry
+  ret void
+}
+
+
 ; Signed Comparisons
 ; ------------------
 
@@ -406,6 +447,46 @@ for.end:                                          ; preds = %for.body, %entry
   ret void
 }
 
+; CHECK-LABEL: Determining loop execution counts for: @slt_129_varying_rhs
+; CHECK: Loop %for.body: Unpredictable backedge-taken count.
+; CHECK: Loop %for.body: Unpredictable max backedge-taken count
+
+define void @slt_129_varying_rhs(i8* %n_p) {
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %entry, %for.body
+  %i.05 = phi i8 [ %add, %for.body ], [ -128, %entry ]
+  %add = add nsw i8 %i.05, 129
+  %n = load i8, i8* %n_p
+  %cmp = icmp slt i8 %add, %n
+  br i1 %cmp, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.body, %entry
+  ret void
+}
+
+; CHECK-LABEL: Determining loop execution counts for: @slt_symbolic_varying_rhs
+; CHECK: Loop %for.body: Unpredictable backedge-taken count.
+; CHECK: Loop %for.body: Unpredictable max backedge-taken count
+
+define void @slt_symbolic_varying_rhs(i8* %n_p, i8 %step) {
+entry:
+  %assume = icmp ult i8 128, %step
+  call void @llvm.assume(i1 %assume)
+  br label %for.body
+
+for.body:                                         ; preds = %entry, %for.body
+  %i.05 = phi i8 [ %add, %for.body ], [ -128, %entry ]
+  %add = add nsw i8 %i.05, %step
+  %n = load i8, i8* %n_p
+  %cmp = icmp slt i8 %add, %n
+  br i1 %cmp, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.body, %entry
+  ret void
+}
+
 declare void @llvm.assume(i1)