src/interp/stack_pop.c


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/*
 * nanowasm, a tiny WebAssembly/Wasm interpreter
 * Copyright (C) 2023-2024  Xavier Del Campo Romero
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at https://mozilla.org/MPL/2.0/.
 */

#include <nanowasm/nw.h>
#include <nw/interp.h>
#include <nw/log.h>
#include <stddef.h>
#include <string.h>

int interp_stack_pop(struct nw_interp *const i, void *const dst,
    const size_t n)
{
    if (i->stack_i < n)
    {
        static const char exc[] = "stack underflow";

        LOG("%s: %s\n", __func__, exc);
        i->exception = exc;
        return -1;
    }

    i->stack_i -= n;
    memcpy(dst, nwp_interp_stackptr(i), n);
    return 0;
}