// EXTRACT_VECTOR_ELT of INSERT_VECTOR_ELT is often formed when vector
// operations are lowered to scalars.
if (N1.getOpcode() == ISD::INSERT_VECTOR_ELT) {
+ // If the indices are the same, return the inserted element.
if (N1.getOperand(2) == N2)
return N1.getOperand(1);
- else
+ // If the indices are known different, extract the element from
+ // the original vector.
+ else if (isa<ConstantSDNode>(N1.getOperand(2)) &&
+ isa<ConstantSDNode>(N2))
return getNode(ISD::EXTRACT_VECTOR_ELT, VT, N1.getOperand(0), N2);
}
break;
--- /dev/null
+; RUN: llvm-as < %s | llc -march=x86 | grep {(%esp,%eax,4)} | count 4
+
+; Inserts and extracts with variable indices must be lowered
+; to memory accesses.
+
+define i32 @t0(i32 inreg %t7, <4 x i32> inreg %t8) nounwind {
+ %t13 = insertelement <4 x i32> %t8, i32 76, i32 %t7
+ %t9 = extractelement <4 x i32> %t13, i32 0
+ ret i32 %t9
+}
+define i32 @t1(i32 inreg %t7, <4 x i32> inreg %t8) nounwind {
+ %t13 = insertelement <4 x i32> %t8, i32 76, i32 0
+ %t9 = extractelement <4 x i32> %t13, i32 %t7
+ ret i32 %t9
+}
+define <4 x i32> @t2(i32 inreg %t7, <4 x i32> inreg %t8) nounwind {
+ %t9 = extractelement <4 x i32> %t8, i32 %t7
+ %t13 = insertelement <4 x i32> %t8, i32 %t9, i32 0
+ ret <4 x i32> %t13
+}
+define <4 x i32> @t3(i32 inreg %t7, <4 x i32> inreg %t8) nounwind {
+ %t9 = extractelement <4 x i32> %t8, i32 0
+ %t13 = insertelement <4 x i32> %t8, i32 %t9, i32 %t7
+ ret <4 x i32> %t13
+}