text: // SPDX-License-Identifier: GPL-2.0
  #include <linux/compiler.h>
  #include <sys/types.h>
  #include <regex.h>
  
  struct arm64_annotate {
  	regex_t call_insn,
  		jump_insn;
  };
  
  static struct ins_ops *arm64__associate_instruction_ops(struct arch *arch, const char *name)
  {
  	struct arm64_annotate *arm = arch->priv;
  	struct ins_ops *ops;
  	regmatch_t match[2];
  
  	if (!regexec(&arm->jump_insn, name, 2, match, 0))
  		ops = &jump_ops;
  	else if (!regexec(&arm->call_insn, name, 2, match, 0))
  		ops = &call_ops;
  	else if (!strcmp(name, "ret"))
  		ops = &ret_ops;
  	else
  		return NULL;
  
  	arch__associate_ins_ops(arch, name, ops);
  	return ops;
  }
  
  static int arm64__annotate_init(struct arch *arch, char *cpuid __maybe_unused)
  {
  	struct arm64_annotate *arm;
  	int err;
  
  	if (arch->initialized)
  		return 0;
  
  	arm = zalloc(sizeof(*arm));
  	if (!arm)
  		return -1;
  
  	/* bl, blr */
  	err = regcomp(&arm->call_insn, "^blr?$", REG_EXTENDED);
  	if (err)
  		goto out_free_arm;
  	/* b, b.cond, br, cbz/cbnz, tbz/tbnz */
  	err = regcomp(&arm->jump_insn, "^[ct]?br?\\.?(cc|cs|eq|ge|gt|hi|le|ls|lt|mi|ne|pl)?n?z?$",
  		      REG_EXTENDED);
  	if (err)
  		goto out_free_call;
  
  	arch->initialized = true;
  	arch->priv	  = arm;
  	arch->associate_instruction_ops   = arm64__associate_instruction_ops;
  	arch->objdump.comment_char	  = '/';
  	arch->objdump.skip_functions_char = '+';
  	return 0;
  
  out_free_call:
  	regfree(&arm->call_insn);
  out_free_arm:
  	free(arm);
  	return -1;
  }
  