Merge pull request #3272 from dheaton-arm/implement-iaddpairwise

Implement `IaddPairwise` for the interpreter

cranelift/filetests/filetests/runtests/simd-iaddpairwise.clif

@@ -0,0 +1,25 @@
+test interpret
+test run
+target aarch64
+
+function %iaddp_i8x16(i8x16, i8x16) -> i8x16 {
+block0(v0: i8x16, v1: i8x16):
+    v2 = iadd_pairwise v0, v1
+    return v2
+}
+; run: %iaddp_i8x16([1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16], [17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32]) == [3 7 11 15 19 23 27 31 35 39 43 47 51 55 59 63]
+
+function %iaddp_i16x8(i16x8, i16x8) -> i16x8 {
+block0(v0: i16x8, v1: i16x8):
+    v2 = iadd_pairwise v0, v1
+    return v2
+}
+; run: %iaddp_i16x8([1 2 3 4 5 6 7 8], [100 99 98 97 96 95 94 93]) == [3 7 11 15 199 195 191 187]
+
+function %iaddp_i32x4(i32x4, i32x4) -> i32x4 {
+block0(v0: i32x4, v1: i32x4):
+    v2 = iadd_pairwise v0, v1
+    return v2
+}
+; run: %iaddp_i32x4([1 2 3 4], [5 6 7 8]) == [3 7 11 15]
+; run: %iaddp_i32x4([4294967290 5 4294967290 5], [100 100 100 100]) == [4294967295 4294967295 200 200]