1 files changed, 51 insertions, 0 deletions
diff --git a/llvm/test/CodeGen/Hexagon/swp-const-tc.ll b/llvm/test/CodeGen/Hexagon/swp-const-tc.ll
new file mode 100644
index 00000000000..3113094d2ba
--- /dev/null
+++ b/llvm/test/CodeGen/Hexagon/swp-const-tc.ll
@@ -0,0 +1,51 @@
+; RUN: llc -march=hexagon -mcpu=hexagonv5 -enable-pipeliner -verify-machineinstrs < %s | FileCheck %s
+
+; If the trip count is a compile-time constant, then decrement it instead
+; of computing a new LC0 value.
+
+; CHECK-LABEL: @test
+; CHECK: loop0(.LBB0_1, #998)
+
+define i32 @test(i32* %A, i32* %B, i32 %count) {
+entry:
+  br label %for.body
+
+for.body:
+  %sum.02 = phi i32 [ 0, %entry ], [ %add, %for.body ]
+  %arrayidx.phi = phi i32* [ %A, %entry ], [ %arrayidx.inc, %for.body ]
+  %i.01 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
+  %0 = load i32, i32* %arrayidx.phi, align 4
+  %add = add nsw i32 %0, %sum.02
+  %inc = add nsw i32 %i.01, 1
+  %exitcond = icmp eq i32 %inc, 1000
+  %arrayidx.inc = getelementptr i32, i32* %arrayidx.phi, i32 1
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:
+  ret i32 %add
+}
+
+; The constant trip count is small enough that the kernel is not executed.
+
+; CHECK-LABEL: @test1
+; CHECK-NOT: loop0(
+
+define i32 @test1(i32* %A, i32* %B, i32 %count) {
+entry:
+  br label %for.body
+
+for.body:
+  %sum.02 = phi i32 [ 0, %entry ], [ %add, %for.body ]
+  %arrayidx.phi = phi i32* [ %A, %entry ], [ %arrayidx.inc, %for.body ]
+  %i.01 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
+  %0 = load i32, i32* %arrayidx.phi, align 4
+  %add = add nsw i32 %0, %sum.02
+  %inc = add nsw i32 %i.01, 1
+  %exitcond = icmp eq i32 %inc, 1
+  %arrayidx.inc = getelementptr i32, i32* %arrayidx.phi, i32 1
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:
+  ret i32 %add
+}
+