instructions.c

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// 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;
}