Test case for PR770

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28198 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/CodeGen/X86/2006-05-08-CoalesceSubRegClass.ll b/test/CodeGen/X86/2006-05-08-CoalesceSubRegClass.ll
new file mode 100644 (file)
index 0000000..35efcee
--- /dev/null
+++ b/test/CodeGen/X86/2006-05-08-CoalesceSubRegClass.ll
@@ -0,0 +1,22 @@
+; Coalescing from R32 to a subset R32_. Once another register coalescer bug is
+; fixed, the movb should go away as well.
+
+; RUN: llvm-as < %s | llc -march=x86 -relocation-model=static | grep 'movl' | wc -l
+
+%B = external global uint
+%C = external global ushort*
+
+void %test(uint %A) {
+       %A = cast uint %A to ubyte
+       %tmp2 = load uint* %B
+       %tmp3 = and ubyte %A, 16
+       %tmp4 = shl uint %tmp2, ubyte %tmp3
+       store uint %tmp4, uint* %B
+       %tmp6 = shr uint %A, ubyte 3
+       %tmp = load ushort** %C
+       %tmp8 = cast ushort* %tmp to uint
+       %tmp9 = add uint %tmp8, %tmp6
+       %tmp9 = cast uint %tmp9 to ushort*
+       store ushort* %tmp9, ushort** %C
+       ret void
+}