Add test showing that MachineLICM is calculating register pressure wrong

More details: http://llvm.org/PR23143

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234309 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/CodeGen/X86/licm-regpressure.ll b/test/CodeGen/X86/licm-regpressure.ll
new file mode 100644 (file)
index 0000000..0ab6554
--- /dev/null
+++ b/test/CodeGen/X86/licm-regpressure.ll
@@ -0,0 +1,39 @@
+; RUN: llc < %s -mtriple=x86_64-linux | FileCheck %s
+; This tests currently fails as MachineLICM does not compute register pressure
+; correctly. More details: llvm.org/PR23143
+; XFAIL: *
+
+; MachineLICM should take register pressure into account.
+; CHECK-NOT: Spill
+
+%struct.A = type { i32, i32, i32, i32, i32, i32, i32 }
+
+define void @test(i1 %b, %struct.A* %a) nounwind {
+entry:
+  br label %loop-header
+
+loop-header:
+  br label %loop-body
+
+loop-body:
+  %0 = getelementptr inbounds %struct.A, %struct.A* %a, i64 0, i32 0
+  %1 = getelementptr inbounds %struct.A, %struct.A* %a, i64 0, i32 1
+  %2 = getelementptr inbounds %struct.A, %struct.A* %a, i64 0, i32 2
+  %3 = getelementptr inbounds %struct.A, %struct.A* %a, i64 0, i32 3
+  %4 = getelementptr inbounds %struct.A, %struct.A* %a, i64 0, i32 4
+  %5 = getelementptr inbounds %struct.A, %struct.A* %a, i64 0, i32 5
+  %6 = getelementptr inbounds %struct.A, %struct.A* %a, i64 0, i32 6
+  call void @assign(i32* %0)
+  call void @assign(i32* %1)
+  call void @assign(i32* %2)
+  call void @assign(i32* %3)
+  call void @assign(i32* %4)
+  call void @assign(i32* %5)
+  call void @assign(i32* %6)
+  br i1 %b, label %loop-body, label %loop-exit
+
+loop-exit:
+  ret void
+}
+
+declare void @assign(i32*)