Use "test reg,reg" in place of "cmp reg,0" for 64-bit operands. This was
previously only done for 32-bit and smaller operands.

llvm-svn: 42024
diff --git a/llvm/test/CodeGen/X86/cmp0.ll b/llvm/test/CodeGen/X86/cmp0.ll
new file mode 100644
index 0000000..f66f90c
--- /dev/null
+++ b/llvm/test/CodeGen/X86/cmp0.ll
@@ -0,0 +1,7 @@
+; RUN: llvm-as < %s | llc -march=x86-64 | grep -v cmp
+
+define i64 @foo(i64 %x) {
+  %t = icmp eq i64 %x, 0
+  %r = zext i1 %t to i64
+  ret i64 %r
+}