Implement splitting support for store, allowing us to compile:

%f8 = type <8 x float>

define void @test_f8(%f8* %P, %f8* %Q, %f8* %S) {
	%p = load %f8* %P		; <%f8> [#uses=1]
	%q = load %f8* %Q		; <%f8> [#uses=1]
	%R = add %f8 %p, %q		; <%f8> [#uses=1]
	store %f8 %R, %f8* %S
	ret void
}

into:

_test_f8:
	movaps	16(%rdi), %xmm0
	addps	16(%rsi), %xmm0
	movaps	(%rdi), %xmm1
	addps	(%rsi), %xmm1
	movaps	%xmm0, 16(%rdx)
	movaps	%xmm1, (%rdx)
	ret



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44725 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/SelectionDAG/LegalizeTypes.h

@@ -281,6 +281,7 @@ private:
   // Operand Vector Scalarization: <128 x ty> -> 2 x <64 x ty>.
   bool SplitOperand(SDNode *N, unsigned OpNo);
   
+  SDOperand SplitOperand_STORE(StoreSDNode *N, unsigned OpNo);
 };
 
 } // end namespace llvm.