/* SPDX-License-Identifier: GPL-2.0 */
#include "sample.h"
#include "debug.h"
#include "thread.h"
#include <elf.h>
#ifndef EM_CSKY
#define EM_CSKY         252
#endif
#ifndef EM_LOONGARCH
#define EM_LOONGARCH    258
#endif
#include <linux/zalloc.h>
#include <stdlib.h>
#include <string.h>
#include "../../arch/x86/include/asm/insn.h"

void perf_sample__init(struct perf_sample *sample, bool all)
{
        if (all) {
                memset(sample, 0, sizeof(*sample));
        } else {
                sample->user_regs = NULL;
                sample->intr_regs = NULL;
        }
}

void perf_sample__exit(struct perf_sample *sample)
{
        free(sample->user_regs);
        free(sample->intr_regs);
}

struct regs_dump *perf_sample__user_regs(struct perf_sample *sample)
{
        if (!sample->user_regs) {
                sample->user_regs = zalloc(sizeof(*sample->user_regs));
                if (!sample->user_regs)
                        pr_err("Failure to allocate sample user_regs");
        }
        return sample->user_regs;
}


struct regs_dump *perf_sample__intr_regs(struct perf_sample *sample)
{
        if (!sample->intr_regs) {
                sample->intr_regs = zalloc(sizeof(*sample->intr_regs));
                if (!sample->intr_regs)
                        pr_err("Failure to allocate sample intr_regs");
        }
        return sample->intr_regs;
}

static int elf_machine_max_instruction_length(uint16_t e_machine)
{
        switch (e_machine) {
        /* Fixed 4-byte (32-bit) architectures */
        case EM_AARCH64:
        case EM_PPC:
        case EM_PPC64:
        case EM_MIPS:
        case EM_SPARC:
        case EM_SPARCV9:
        case EM_ALPHA:
        case EM_LOONGARCH:
        case EM_PARISC:
        case EM_SH:
                return 4;

        /* Variable length or mixed-mode architectures */
        case EM_ARM:    /* Variable due to Thumb/Thumb-2 */
        case EM_RISCV:  /* Variable due to Compressed (C) extension */
        case EM_CSKY:   /* Variable (16 or 32 bit) */
        case EM_ARC:    /* Variable (ARCompact) */
                return 4;
        case EM_S390:   /* Variable (2, 4, or 6 bytes) */
                return 6;
        case EM_68K:
                return 10;
        case EM_386:
        case EM_X86_64:
                return 15;
        case EM_XTENSA: /* Variable (FLIX) */
                return 16;
        default:
                return MAX_INSN;
        }
}

void perf_sample__fetch_insn(struct perf_sample *sample,
                             struct thread *thread,
                             struct machine *machine)
{
        int ret, len;
        bool is64bit = false;
        uint16_t e_machine;

        if (!sample->ip || sample->insn_len != 0)
                return;

        e_machine = thread__e_machine(thread, machine, /*e_flags=*/NULL);
        len = elf_machine_max_instruction_length(e_machine);
        len = thread__memcpy(thread, machine, sample->insn,
                             sample->ip, len,
                             &is64bit);
        if (len <= 0)
                return;

        sample->insn_len = len;

        if (e_machine == EM_386 || e_machine == EM_X86_64) {
                /* Refine the x86 instruction length with the decoder. */
                struct insn insn;

                ret = insn_decode(&insn, sample->insn, len,
                                  is64bit ? INSN_MODE_64 : INSN_MODE_32);
                if (ret >= 0 && insn.length <= len)
                        sample->insn_len = insn.length;
        }
}