[Sparc] Use synthetic instruction clr to zero register instead of sethi

Using `clr reg`/`mov %g0, reg`/`or %g0, %g0, reg` to zero a register
looks much better than `sethi 0, reg`.

Reviewers: jyknight, venkatra

Reviewed By: jyknight

Subscribers: eraman, fedor.sergeev, jrtc27, llvm-commits

Differential Revision: https://reviews.llvm.org/D45810

llvm-svn: 330396
diff --git a/llvm/test/CodeGen/SPARC/inlineasm.ll b/llvm/test/CodeGen/SPARC/inlineasm.ll
index d4584f8..7bf0f74 100644
--- a/llvm/test/CodeGen/SPARC/inlineasm.ll
+++ b/llvm/test/CodeGen/SPARC/inlineasm.ll
@@ -84,7 +84,7 @@
 
 ;; Ensures that tied in and out gets allocated properly.
 ; CHECK-LABEL: test_i64_inout:
-; CHECK: sethi 0, %o2
+; CHECK: mov %g0, %o2
 ; CHECK: mov 5, %o3
 ; CHECK: xor %o2, %g0, %o2
 ; CHECK: mov %o2, %o0