{"ast_node_type":"other","tokens":[{"end":240,"kind":"keyword","start":0,"text":"|"}]}
| All          | `fr` (Hexagon), `fp` (PowerPC), `$fp` (MIPS), `Y` (AVR), `r4` (MSP430), `a6` (M68k), `r30`/`i6` (SPARC) | The frame pointer cannot be used as an input or output.                                                             |
| All          | `sp`, `r14`/`o6` (SPARC)                | The stack pointer must be restored to its original value at the end of an asm code block.                                                                                           |
| All          | `r19` (Hexagon), `r29` (PowerPC), `r30` (PowerPC) | These are used internally by LLVM as "base pointer" for functions with complex stack frames.                                                                              |