Following String intrinsics are not yet implemented (for CompactStrings):
 0 string_compareL
 1 string_compareU
 2 string_compareLU
 3 string_compareUL
 4 string_equalsL
 5 string_equalsU
 6 array_equalsB
 7 array_equalsC
 8 indexOf_imm1_char_U
 9 indexOf_imm1_char_L
10 indexOf_imm1_char_UL
11 indexOf_imm1_U
12 indexOf_imm1_L
13 indexOf_imm1_UL
14 indexOfChar_U
15 indexOf_imm_U
16 indexOf_imm_L
17 indexOf_imm_UL
18 indexOf_U
19 indexOf_L
20 indexOf_UL
21 string_compress
22 string_inflate
23 has_negatives
24 encode_iso_array