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path: root/plugins/MirLua/Modules/ffi/src/call_x86.h
blob: 5ffe328eb3fd0c72eaa2b3fe5ab1db8787b29be2 (plain)
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/*
** This file has been pre-processed with DynASM.
** http://luajit.org/dynasm.html
** DynASM version 1.3.0, DynASM x86 version 1.3.0
** DO NOT EDIT! The original file is in "call_x86.dasc".
*/

#if DASM_VERSION != 10300
#error "Version mismatch between DynASM and included encoding engine"
#endif

/* vim: ts=4 sw=4 sts=4 et tw=78
 * Portions copyright (c) 2015-present, Facebook, Inc. All rights reserved.
 * Portions copyright (c) 2011 James R. McKaskill.
 *
 * This source code is licensed under the BSD-style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 */

static const unsigned char build_actionlist[1800] = {
  248,10,184,1,0,0,0,139,117,252,248,139,125,252,252,137,252,236,93,195,255,
  248,11,232,251,1,0,185,237,137,1,184,0,0,0,0,139,117,252,248,139,125,252,
  252,137,252,236,93,195,255,248,12,221,92,36,4,232,251,1,0,185,237,137,1,137,
  60,36,232,251,1,1,252,233,244,10,255,248,13,15,182,192,137,68,36,32,232,251,
  1,0,185,237,137,1,139,68,36,32,137,68,36,4,137,60,36,232,251,1,2,252,233,
  244,10,255,248,14,137,68,36,32,232,251,1,0,185,237,137,1,139,68,36,32,137,
  68,36,4,137,60,36,232,251,1,3,252,233,244,10,255,248,15,137,68,36,32,232,
  251,1,0,185,237,137,1,139,68,36,32,137,68,36,4,137,60,36,232,251,1,4,252,
  233,244,10,255,248,16,102,184,0,0,199,68,36,4,237,137,60,36,232,251,1,5,255,
  248,17,102,184,0,0,199,68,36,4,237,137,60,36,232,251,1,5,255,248,18,137,77,
  252,248,137,85,252,244,195,255,139,141,233,255,139,141,233,139,149,233,255,
  137,132,253,36,233,255,137,132,253,36,233,137,148,253,36,233,255,221,133,
  233,255,217,133,233,255,252,243,15,126,133,233,255,252,243,15,90,133,233,
  255,221,156,253,36,233,255,217,156,253,36,233,255,102,15,214,132,253,36,233,
  255,252,242,15,90,192,102,15,214,132,253,36,233,255,252,242,15,90,192,102,
  15,126,132,253,36,233,255,85,137,229,87,129,252,236,239,255,232,244,18,255,
  191,237,255,199,68,36,8,237,199,68,36,4,237,137,60,36,232,251,1,6,255,199,
  68,36,8,237,199,68,36,4,252,255,252,255,252,255,252,255,137,60,36,232,251,
  1,6,255,199,68,36,8,237,199,68,36,4,237,137,60,36,232,251,1,6,199,68,36,8,
  237,199,68,36,4,252,255,252,255,252,255,252,255,137,60,36,232,251,1,7,255,
  137,8,199,68,36,4,252,254,252,255,252,255,252,255,137,60,36,232,251,1,8,255,
  199,68,36,8,237,199,68,36,4,0,0,0,0,137,60,36,232,251,1,7,255,137,8,137,80,
  4,255,137,8,255,102,15,214,0,255,217,24,255,217,88,4,255,221,24,255,221,88,
  8,255,221,92,36,4,137,60,36,232,251,1,1,255,15,182,201,137,76,36,4,137,60,
  36,232,251,1,2,255,15,182,201,255,15,190,201,255,137,76,36,4,137,60,36,232,
  251,1,3,255,15,183,201,255,15,191,201,255,137,76,36,4,137,60,36,232,251,1,
  4,255,199,68,36,12,0,0,0,0,199,68,36,8,237,199,68,36,4,237,137,60,36,232,
  251,1,9,255,199,68,36,8,237,199,68,36,4,252,254,252,255,252,255,252,255,137,
  60,36,232,251,1,6,199,68,36,12,237,199,68,36,8,252,255,252,255,252,255,252,
  255,199,68,36,4,252,254,252,255,252,255,252,255,137,60,36,232,251,1,10,137,
  68,36,32,199,68,36,4,252,252,252,255,252,255,252,255,137,60,36,232,251,1,
  11,139,68,36,32,255,199,68,36,8,237,199,68,36,4,252,254,252,255,252,255,252,
  255,137,60,36,232,251,1,6,199,68,36,12,237,199,68,36,8,252,255,252,255,252,
  255,252,255,199,68,36,4,252,254,252,255,252,255,252,255,137,60,36,232,251,
  1,12,137,68,36,32,199,68,36,4,252,252,252,255,252,255,252,255,137,60,36,232,
  251,1,11,139,68,36,32,255,199,68,36,4,252,254,252,255,252,255,252,255,137,
  60,36,232,251,1,11,255,199,68,36,4,252,255,252,255,252,255,252,255,137,60,
  36,232,251,1,13,255,199,68,36,4,252,255,252,255,252,255,252,255,137,60,36,
  232,251,1,14,255,137,68,36,32,199,68,36,4,252,253,252,255,252,255,252,255,
  137,60,36,232,251,1,11,139,68,36,32,255,199,68,36,4,252,255,252,255,252,255,
  252,255,137,60,36,232,251,1,15,255,199,68,36,4,252,255,252,255,252,255,252,
  255,137,60,36,232,251,1,16,255,137,68,36,32,137,84,36,36,199,68,36,4,252,
  253,252,255,252,255,252,255,137,60,36,232,251,1,11,139,68,36,32,139,84,36,
  36,255,199,68,36,4,252,255,252,255,252,255,252,255,137,60,36,232,251,1,17,
  137,68,36,32,199,68,36,4,252,253,252,255,252,255,252,255,137,60,36,232,251,
  1,11,139,68,36,32,255,199,68,36,4,252,255,252,255,252,255,252,255,137,60,
  36,232,251,1,18,255,221,92,36,32,199,68,36,4,252,253,252,255,252,255,252,
  255,137,60,36,232,251,1,11,221,68,36,32,255,199,68,36,4,252,255,252,255,252,
  255,252,255,137,60,36,232,251,1,19,137,68,36,32,137,84,36,36,199,68,36,4,
  252,253,252,255,252,255,252,255,137,60,36,232,251,1,11,139,68,36,32,139,84,
  36,36,255,199,68,36,4,252,255,252,255,252,255,252,255,137,60,36,232,251,1,
  20,102,15,214,68,36,32,102,15,214,76,36,40,199,68,36,4,252,253,252,255,252,
  255,252,255,137,60,36,232,251,1,11,252,243,15,126,68,36,32,252,243,15,126,
  76,36,40,255,139,141,233,199,68,36,8,252,255,252,255,252,255,252,255,137,
  124,36,4,137,12,36,232,251,1,20,131,252,236,4,199,68,36,4,252,253,252,255,
  252,255,252,255,137,60,36,232,251,1,11,255,139,125,252,252,137,252,236,93,
  194,236,255,85,137,229,87,86,139,189,233,131,252,236,16,137,60,36,232,251,
  1,21,137,198,129,252,248,239,15,140,244,16,255,15,143,244,17,255,193,224,
  4,41,196,129,252,236,239,255,199,68,36,8,237,199,68,36,4,0,0,0,0,137,60,36,
  232,251,1,7,131,252,236,16,255,199,68,36,12,237,199,68,36,8,237,199,68,36,
  4,237,137,60,36,232,251,1,10,255,199,68,36,12,237,199,68,36,8,237,199,68,
  36,4,237,137,60,36,232,251,1,22,255,199,68,36,12,237,199,68,36,8,237,199,
  68,36,4,237,137,60,36,232,251,1,12,255,199,68,36,4,237,137,60,36,232,251,
  1,14,255,15,182,192,255,15,190,192,255,15,183,192,255,15,191,192,255,199,
  68,36,4,237,137,60,36,232,251,1,14,131,252,248,0,15,149,208,15,182,192,255,
  199,68,36,4,237,137,60,36,232,251,1,13,255,199,68,36,4,237,137,60,36,232,
  251,1,17,255,199,68,36,4,237,137,60,36,232,251,1,15,255,199,68,36,4,237,137,
  60,36,232,251,1,16,255,199,68,36,4,237,137,60,36,232,251,1,18,255,199,68,
  36,4,237,137,60,36,232,251,1,20,255,252,243,15,126,193,255,141,132,253,36,
  233,131,252,236,4,199,68,36,8,237,137,124,36,4,137,4,36,232,251,1,20,255,
  199,68,36,4,237,137,60,36,232,251,1,19,255,199,68,36,4,237,137,60,36,232,
  251,1,19,137,4,36,217,4,36,255,137,20,36,217,4,36,255,137,224,129,192,239,
  137,68,36,12,137,116,36,8,199,68,36,4,237,137,60,36,232,251,1,23,255,185,
  237,139,1,137,4,36,232,251,1,24,255,131,196,32,255,139,148,253,36,233,255,
  139,12,36,255,129,196,239,255,232,251,1,25,131,252,236,48,255,137,68,36,32,
  232,251,1,0,185,237,137,1,199,68,36,8,237,199,68,36,4,237,137,60,36,232,251,
  1,7,139,76,36,32,137,8,252,233,244,10,255,137,84,36,36,137,68,36,32,232,251,
  1,0,185,237,137,1,199,68,36,8,237,199,68,36,4,0,0,0,0,137,60,36,232,251,1,
  7,139,76,36,36,139,84,36,32,137,72,4,137,16,252,233,244,10,255,137,68,36,
  32,137,84,36,36,232,251,1,0,185,237,137,1,199,68,36,8,237,199,68,36,4,237,
  137,60,36,232,251,1,7,139,76,36,32,137,8,139,76,36,36,137,72,4,252,233,244,
  10,255,131,252,236,4,232,251,1,0,185,237,137,1,252,233,244,10,255,252,233,
  244,11,255,252,233,244,13,255,252,233,244,14,255,252,233,244,15,255,252,233,
  244,12,255
};

static const char *const globnames[] = {
  "lua_return_arg",
  "lua_return_void",
  "lua_return_double",
  "lua_return_bool",
  "lua_return_int",
  "lua_return_uint",
  "too_few_arguments",
  "too_many_arguments",
  "save_registers",
  (const char *)0
};
static const char *const extnames[] = {
  "GetLastError",
  "lua_pushnumber",
  "lua_pushboolean",
  "push_int",
  "push_uint",
  "luaL_error",
  "lua_rawgeti",
  "push_cdata",
  "lua_remove",
  "lua_callk",
  "check_typed_pointer",
  "lua_settop",
  "check_enum",
  "check_uint32",
  "check_int32",
  "check_uint64",
  "check_int64",
  "check_uintptr",
  "check_double",
  "check_complex_float",
  "check_complex_double",
  "lua_gettop",
  "check_typed_cfunction",
  "unpack_varargs_stack",
  "SetLastError",
  "FUNCTION",
  (const char *)0
};



#if defined _WIN64 || defined __amd64__
#define JUMP_SIZE 14
#else
#define JUMP_SIZE 4
#endif

#define MIN_BRANCH INT32_MIN
#define MAX_BRANCH INT32_MAX
#define BRANCH_OFF 4

static void compile_extern_jump(struct jit* jit, lua_State* L, cfunction func, uint8_t* code)
{
    /* The jump code is the function pointer followed by a stub to call the
     * function pointer. The stub exists in 64 bit so we can jump to functions
     * with an offset greater than 2 GB.
     *
     * Note we have to manually set this up since there are commands buffered
     * in the jit state and dynasm doesn't support rip relative addressing.
     *
     * eg on 64 bit:
     * 0-8: function ptr
     * 8-14: jmp aword [rip-14]
     *
     * for 32 bit we only set the function ptr as it can always fit in a 32
     * bit displacement
     */
#if defined _WIN64 || defined __amd64__
    *(cfunction*) code = func;
    code[8] = 0xFF; /* FF /4 operand for jmp */
    code[9] = 0x25; /* RIP displacement */
    *(int32_t*) &code[10] = -14;
#else
    *(cfunction*) code = func;
#endif
}

void compile_globals(struct jit* jit, lua_State* L)
{
    struct jit* Dst = jit;
    int* perr = &jit->last_errno;
    dasm_setup(Dst, build_actionlist);

    /* Note: since the return code uses EBP to reset the stack pointer, we
     * don't have to track the amount of stack space used. It also means we
     * can handle stdcall and cdecl with the same code.
     */

    /* Note the various call_* functions want 32 bytes of 16 byte aligned
     * stack
     */




    /* the general idea for the return functions is:
     * 1) Save return value on stack
     * 2) Call get_errno (this trashes the registers hence #1)
     * 3) Unpack return value from stack
     * 4) Call lua push function
     * 5) Set eax to number of returned args (0 or 1)
     * 6) Call return which pops our stack frame
     */

    dasm_put(Dst, 0);

    dasm_put(Dst, 21, perr);

    dasm_put(Dst, 50, perr);

    dasm_put(Dst, 76, perr);

    dasm_put(Dst, 113, perr);

    dasm_put(Dst, 147, perr);

    dasm_put(Dst, 181, (ptrdiff_t)("too few arguments"));

    dasm_put(Dst, 200, (ptrdiff_t)("too many arguments"));

    dasm_put(Dst, 219);

    compile(Dst, L, NULL, LUA_NOREF);
}

int x86_return_size(lua_State* L, int usr, const struct ctype* ct)
{
    int ret = 0;
    const struct ctype* mt;

    if (ct->calling_convention != C_CALL) {
        size_t i;
        size_t argn = lua_rawlen(L, usr);
        for (i = 1; i <= argn; i++) {
            lua_rawgeti(L, usr, (int) i);
            mt = (const struct ctype*) lua_touserdata(L, -1);

            if (mt->pointers || mt->is_reference) {
                ret += sizeof(void*);
            } else {
                switch (mt->type) {
                case DOUBLE_TYPE:
                case COMPLEX_FLOAT_TYPE:
                case INT64_TYPE:
                    ret += 8;
                    break;
                case COMPLEX_DOUBLE_TYPE:
                    ret += 16;
                    break;
                case INTPTR_TYPE:
                    ret += sizeof(intptr_t);
                    break;
                case FUNCTION_PTR_TYPE:
                    ret += sizeof(cfunction);
                    break;
                case BOOL_TYPE:
                case FLOAT_TYPE:
                case INT8_TYPE:
                case INT16_TYPE:
                case INT32_TYPE:
                case ENUM_TYPE:
                    ret += 4;
                    break;
                default:
                    return luaL_error(L, "NYI - argument type");
                }
            }

            lua_pop(L, 1);
        }
    }

#if !defined _WIN64 && !defined __amd64__
    lua_rawgeti(L, usr, 0);
    mt = (const struct ctype*) lua_touserdata(L, -1);
    if (!mt->pointers && !mt->is_reference && mt->type == COMPLEX_DOUBLE_TYPE) {
        ret += sizeof(void*);
    }
    lua_pop(L, 1);
#endif

    return ret;
}

#ifdef _WIN64
#define MAX_REGISTERS(ct) 4 /* rcx, rdx, r8, r9 */

#elif defined __amd64__
#define MAX_INT_REGISTERS(ct) 6 /* rdi, rsi, rdx, rcx, r8, r9 */
#define MAX_FLOAT_REGISTERS(ct) 8 /* xmm0-7 */

#else
#define MAX_INT_REGISTERS(ct) ((ct)->calling_convention == FAST_CALL ? 2 /* ecx, edx */ : 0)
#define MAX_FLOAT_REGISTERS(ct) 0
#endif

struct reg_alloc {
#ifdef _WIN64
    int regs;
    int is_float[4];
    int is_int[4];
#else
    int floats;
    int ints;
#endif
    int off;
};

#ifdef _WIN64
#define REGISTER_STACK_SPACE(ct) (4*8)
#elif defined __amd64__
#define REGISTER_STACK_SPACE(ct) (14*8)
#else
#define REGISTER_STACK_SPACE(ct) ALIGN_UP(((ct)->calling_convention == FAST_CALL ? 2*4 : 0), 15)
#endif

/* Fastcall:
 * Uses ecx, edx as first two int registers
 * Everything else on stack (include 64bit ints)
 * No overflow stack space
 * Pops the stack before returning
 * Returns int in eax, float in ST0
 * We use the same register allocation logic as posix x64 with 2 int regs and 0 float regs
 */

static void get_int(Dst_DECL, const struct ctype* ct, struct reg_alloc* reg, int is_int64)
{
    /* grab the register from the shadow space */
#ifdef _WIN64
    if (reg->regs < MAX_REGISTERS(ct)) {
        dasm_put(Dst, 231, 16 + 8*reg->regs);
        reg->regs++;
    }
#elif __amd64__
    if (reg->ints < MAX_INT_REGISTERS(ct)) {
        dasm_put(Dst, 231, - 80 - 8*reg->ints);
        reg->ints++;
    }
#else
    if (!is_int64 && reg->ints < MAX_INT_REGISTERS(ct)) {
        dasm_put(Dst, 231, - 8 - 4*reg->ints);
        reg->ints++;
    }
#endif
    else if (is_int64) {
        dasm_put(Dst, 235, reg->off, reg->off + 4);
        reg->off += 8;
    } else {
        dasm_put(Dst, 231, reg->off);
        reg->off += 4;
    }
}

static void add_int(Dst_DECL, const struct ctype* ct, struct reg_alloc* reg, int is_int64)
{
#ifdef _WIN64
    if (reg->regs < MAX_REGISTERS(ct)) {
        dasm_put(Dst, 242, 32 + 8*(reg->regs));
        reg->is_int[reg->regs++] = 1;
    }
#elif __amd64__
    if (reg->ints < MAX_INT_REGISTERS(ct)) {
        dasm_put(Dst, 242, 32 + 8*reg->ints);
        reg->ints++;
    }
#else
    if (!is_int64 && reg->ints < MAX_INT_REGISTERS(ct)) {
        dasm_put(Dst, 242, 32 + 4*reg->ints);
        reg->ints++;
    }
#endif
    else {
#if defined _WIN64 || defined __amd64__
        if (reg->off % 8 != 0) {
            reg->off += 8 - (reg->off % 8);
        }
#endif
        if (is_int64) {
            dasm_put(Dst, 248, reg->off, reg->off + 4);
            reg->off += 8;
        } else {
            dasm_put(Dst, 242, reg->off);
            reg->off += 4;
        }
    }
}

static void get_float(Dst_DECL, const struct ctype* ct, struct reg_alloc* reg, int is_double)
{
#if !defined _WIN64 && !defined __amd64__
    assert(MAX_FLOAT_REGISTERS(ct) == 0);
    if (is_double) {
        dasm_put(Dst, 259, reg->off);
        reg->off += 8;
    } else {
        dasm_put(Dst, 263, reg->off);
        reg->off += 4;
    }
#else
    int off;

#ifdef _WIN64
    if (reg->regs < MAX_REGISTERS(ct)) {
        off = -16 - 8*reg->regs;
        reg->regs++;
    }
#else
    if (reg->floats < MAX_FLOAT_REGISTERS(ct)) {
        off = -16 - 8*reg->floats;
        reg->floats++;
    }
#endif
    else {
        off = reg->off;
        reg->off += is_double ? 8 : 4;
    }

    if (is_double) {
        dasm_put(Dst, 267, off);
    } else {
        dasm_put(Dst, 274, off);
    }
#endif
}

static void add_float(Dst_DECL, const struct ctype* ct, struct reg_alloc* reg, int is_double)
{
#if !defined _WIN64 && !defined __amd64__
    assert(MAX_FLOAT_REGISTERS(ct) == 0);
    if (is_double) {
        dasm_put(Dst, 281, reg->off);
        reg->off += 8;
    } else {
        dasm_put(Dst, 287, reg->off);
        reg->off += 4;
    }
#else

#ifdef _WIN64
    if (reg->regs < MAX_REGISTERS(ct)) {
        if (is_double) {
            dasm_put(Dst, 293, 32 + 8*(reg->regs));
        } else {
            dasm_put(Dst, 301, 32 + 8*(reg->regs));
        }
        reg->is_float[reg->regs++] = 1;
    }
#else
    if (reg->floats < MAX_FLOAT_REGISTERS(ct)) {
        if (is_double) {
            dasm_put(Dst, 293, 32 + 8*(MAX_INT_REGISTERS(ct) + reg->floats));
        } else {
            dasm_put(Dst, 301, 32 + 8*(MAX_INT_REGISTERS(ct) + reg->floats));
        }
        reg->floats++;
    }
#endif

    else if (is_double) {
        dasm_put(Dst, 293, reg->off);
        reg->off += 8;
    } else {
        dasm_put(Dst, 314, reg->off);
        reg->off += 4;
    }
#endif
}

#if defined _WIN64 || defined __amd64__
#define add_pointer(jit, ct, reg) add_int(jit, ct, reg, 1)
#define get_pointer(jit, ct, reg) get_int(jit, ct, reg, 1)
#else
#define add_pointer(jit, ct, reg) add_int(jit, ct, reg, 0)
#define get_pointer(jit, ct, reg) get_int(jit, ct, reg, 0)
#endif

cfunction compile_callback(lua_State* L, int fidx, int ct_usr, const struct ctype* ct)
{
    int i, nargs;
    cfunction* pf;
    struct ctype ct2 = *ct;
    const struct ctype* mt;
    struct reg_alloc reg;
    int num_upvals = 0;
    int top = lua_gettop(L);
    struct jit* Dst = get_jit(L);
    int ref;
    int hidden_arg_off = 0;

    ct_usr = lua_absindex(L, ct_usr);
    fidx = lua_absindex(L, fidx);

    assert(lua_isnil(L, fidx) || lua_isfunction(L, fidx));

    memset(&reg, 0, sizeof(reg));
#ifdef _WIN64
    reg.off = 16 + REGISTER_STACK_SPACE(ct); /* stack registers are above the shadow space */
#elif __amd64__
    reg.off = 16;
#else
    reg.off = 8;
#endif

    dasm_setup(Dst, build_actionlist);

    // add a table to store ctype and function upvalues
    // callback_set assumes the first value is the lua function
    nargs = (int) lua_rawlen(L, ct_usr);
    lua_newtable(L);
    lua_pushvalue(L, -1);
    ref = luaL_ref(L, LUA_REGISTRYINDEX);

    if (ct->has_var_arg) {
        luaL_error(L, "can't create callbacks with varargs");
    }

    // setup a stack frame to hold args for the call into lua_call

    dasm_put(Dst, 327, 4 + 16 + 32 + REGISTER_STACK_SPACE(ct));
    if (ct->calling_convention == FAST_CALL) {
        dasm_put(Dst, 336);
    }

    // hardcode the lua_State* value into the assembly
    dasm_put(Dst, 340, L);

    /* get the upval table */
    dasm_put(Dst, 343, ref, LUA_REGISTRYINDEX);

    /* get the lua function */
    lua_pushvalue(L, fidx);
    lua_rawseti(L, -2, ++num_upvals);
    assert(num_upvals == CALLBACK_FUNC_USR_IDX);
    dasm_put(Dst, 361, num_upvals);

#if !defined _WIN64 && !defined __amd64__
    lua_rawgeti(L, ct_usr, 0);
    mt = (const struct ctype*) lua_touserdata(L, -1);
    if (!mt->pointers && !mt->is_reference && mt->type == COMPLEX_DOUBLE_TYPE) {
        hidden_arg_off = reg.off;
        reg.off += sizeof(void*);
    }
    lua_pop(L, 1);
#else
    (void) hidden_arg_off;
#endif

    for (i = 1; i <= nargs; i++) {
        lua_rawgeti(L, ct_usr, i);
        mt = (const struct ctype*) lua_touserdata(L, -1);

        if (mt->pointers || mt->is_reference) {
            lua_getuservalue(L, -1);
            lua_rawseti(L, -3, ++num_upvals); /* usr value */
            lua_rawseti(L, -2, ++num_upvals); /* mt */
            /* on the lua stack in the callback:
             * upval tbl, lua func, i-1 args
             */
            dasm_put(Dst, 386, num_upvals-1, -i-1, mt);
            get_pointer(Dst, ct, &reg);
            dasm_put(Dst, 428);
        } else {
            switch (mt->type) {
            case INT64_TYPE:
                lua_getuservalue(L, -1);
                lua_rawseti(L, -3, ++num_upvals); /* mt */
                lua_pop(L, 1);
                dasm_put(Dst, 450, mt);
                get_int(Dst, ct, &reg, 1);
                dasm_put(Dst, 471);
                break;

            case INTPTR_TYPE:
                lua_getuservalue(L, -1);
                lua_rawseti(L, -3, ++num_upvals); /* mt */
                lua_pop(L, 1);
                dasm_put(Dst, 450, mt);
                get_pointer(Dst, ct, &reg);
                dasm_put(Dst, 477);
                break;

            case COMPLEX_FLOAT_TYPE:
                lua_pop(L, 1);
#if defined _WIN64 || defined __amd64__
                /* complex floats are two floats packed into a double */
                dasm_put(Dst, 450, mt);
                get_float(Dst, ct, &reg, 1);
                dasm_put(Dst, 480);
#else
                /* complex floats are real followed by imag on the stack */
                dasm_put(Dst, 450, mt);
                get_float(Dst, ct, &reg, 0);
                dasm_put(Dst, 485);
                get_float(Dst, ct, &reg, 0);
                dasm_put(Dst, 488);
#endif
                break;

            case COMPLEX_DOUBLE_TYPE:
                lua_pop(L, 1);
                dasm_put(Dst, 450, mt);
                /* real */
                get_float(Dst, ct, &reg, 1);
                dasm_put(Dst, 492);
                /* imag */
                get_float(Dst, ct, &reg, 1);
                dasm_put(Dst, 495);
                break;

            case FLOAT_TYPE:
            case DOUBLE_TYPE:
                lua_pop(L, 1);
                get_float(Dst, ct, &reg, mt->type == DOUBLE_TYPE);
                dasm_put(Dst, 499);
                break;

            case BOOL_TYPE:
                lua_pop(L, 1);
                get_int(Dst, ct, &reg, 0);
                dasm_put(Dst, 511);
                break;

            case INT8_TYPE:
                lua_pop(L, 1);
                get_int(Dst, ct, &reg, 0);
                if (mt->is_unsigned) {
                    dasm_put(Dst, 526);
                } else {
                    dasm_put(Dst, 530);
                }
                dasm_put(Dst, 534);
                break;

            case INT16_TYPE:
                lua_pop(L, 1);
                get_int(Dst, ct, &reg, 0);
                if (mt->is_unsigned) {
                    dasm_put(Dst, 546);
                } else {
                    dasm_put(Dst, 550);
                }
                dasm_put(Dst, 534);
                break;

            case ENUM_TYPE:
            case INT32_TYPE:
                lua_pop(L, 1);
                get_int(Dst, ct, &reg, 0);
                if (mt->is_unsigned) {
                    dasm_put(Dst, 554);
                } else {
                    dasm_put(Dst, 534);
                }
                break;

            default:
                luaL_error(L, "NYI: callback arg type");
            }
        }
    }

    lua_rawgeti(L, ct_usr, 0);
    mt = (const struct ctype*) lua_touserdata(L, -1);

    dasm_put(Dst, 566, (mt->pointers || mt->is_reference || mt->type != VOID_TYPE) ? 1 : 0, nargs);

    // Unpack the return argument if not "void", also clean-up the lua stack
    // to remove the return argument and bind table. Use lua_settop rather
    // than lua_pop as lua_pop is implemented as a macro.
    if (mt->pointers || mt->is_reference) {
        lua_getuservalue(L, -1);
        lua_rawseti(L, -3, ++num_upvals); /* usr value */
        lua_rawseti(L, -2, ++num_upvals); /* mt */
        dasm_put(Dst, 592, num_upvals-1, mt);

    } else {
        switch (mt->type) {
        case ENUM_TYPE:
            lua_getuservalue(L, -1);
            lua_rawseti(L, -3, ++num_upvals); /* usr value */
            lua_rawseti(L, -2, ++num_upvals); /* mt */
            dasm_put(Dst, 680, num_upvals-1, mt);
            break;

        case VOID_TYPE:
            lua_pop(L, 1);
            dasm_put(Dst, 768);
            break;

        case BOOL_TYPE:
        case INT8_TYPE:
        case INT16_TYPE:
        case INT32_TYPE:
            lua_pop(L, 1);
            if (mt->is_unsigned) {
                dasm_put(Dst, 788);
            } else {
                dasm_put(Dst, 808);
            }
            dasm_put(Dst, 828);
            break;

        case INT64_TYPE:
            lua_pop(L, 1);

            if (mt->is_unsigned) {
                dasm_put(Dst, 856);
            } else {
                dasm_put(Dst, 876);
            }

            dasm_put(Dst, 896);
            break;

        case INTPTR_TYPE:
            lua_pop(L, 1);
            dasm_put(Dst, 932);
            break;

        case FLOAT_TYPE:
        case DOUBLE_TYPE:
            lua_pop(L, 1);
            dasm_put(Dst, 979);
            if (mt->type == FLOAT_TYPE) {
            } else {
            }
            dasm_put(Dst, 999);
            break;

        case COMPLEX_FLOAT_TYPE:
            lua_pop(L, 1);
#if !defined HAVE_COMPLEX
            luaL_error(L, "ffi lib compiled without complex number support");
#endif
            /* on 64 bit complex floats are two floats packed into a double,
             * on 32 bit returned complex floats use eax and edx */
            dasm_put(Dst, 1027);
            break;

        case COMPLEX_DOUBLE_TYPE:
            lua_pop(L, 1);
#if !defined HAVE_COMPLEX
            luaL_error(L, "ffi lib compiled without complex number support");
#endif
            /* on 64 bit, returned complex doubles use xmm0, xmm1, on 32 bit
             * there is a hidden first parameter that points to 16 bytes where
             * the returned arg is stored which is popped by the called
             * function */
#if defined _WIN64 || defined __amd64__
            dasm_put(Dst, 1082);
#else
            dasm_put(Dst, 1147, hidden_arg_off);
#endif
            break;

        default:
            luaL_error(L, "NYI: callback return type");
        }
    }

    dasm_put(Dst, 1197, x86_return_size(L, ct_usr, ct));

    lua_pop(L, 1); /* upval table - already in registry */
    assert(lua_gettop(L) == top);

    ct2.is_jitted = 1;
    pf = (cfunction*) push_cdata(L, ct_usr, &ct2);
    *pf = compile(Dst, L, NULL, ref);

    assert(lua_gettop(L) == top + 1);

    return *pf;
}

void compile_function(lua_State* L, cfunction func, int ct_usr, const struct ctype* ct)
{
    size_t i, nargs;
    int num_upvals;
    const struct ctype* mbr_ct;
    struct jit* Dst = get_jit(L);
    struct reg_alloc reg;
    void* p;
    int top = lua_gettop(L);
    int* perr = &Dst->last_errno;

    ct_usr = lua_absindex(L, ct_usr);

    memset(&reg, 0, sizeof(reg));
    reg.off = 32 + REGISTER_STACK_SPACE(ct);

    dasm_setup(Dst, build_actionlist);

    p = push_cdata(L, ct_usr, ct);
    *(cfunction*) p = func;
    num_upvals = 1;

    nargs = lua_rawlen(L, ct_usr);

    if (ct->calling_convention != C_CALL && ct->has_var_arg) {
        luaL_error(L, "vararg is only allowed with the c calling convention");
    }

    dasm_put(Dst, 1208, 8, nargs);

    if (!ct->has_var_arg) {
        dasm_put(Dst, 1238);
    }

    /* no need to zero extend eax returned by lua_gettop to rax as x86-64
     * preguarentees that the upper 32 bits will be zero */
    dasm_put(Dst, 1243, 32 + REGISTER_STACK_SPACE(ct));

#if !defined _WIN64 && !defined __amd64__
    /* Returned complex doubles require a hidden first parameter where the
     * data is stored, which is popped by the calling code. */
    lua_rawgeti(L, ct_usr, 0);
    mbr_ct = (const struct ctype*) lua_touserdata(L, -1);
    if (!mbr_ct->pointers && !mbr_ct->is_reference && mbr_ct->type == COMPLEX_DOUBLE_TYPE) {
        /* we can allocate more space for arguments as long as no add_*
         * function has been called yet, mbr_ct will be added as an upvalue in
         * the return processing later */
        dasm_put(Dst, 1253, mbr_ct);
        add_pointer(Dst, ct, &reg);
    }
    lua_pop(L, 1);
#endif

    for (i = 1; i <= nargs; i++) {
        lua_rawgeti(L, ct_usr, (int) i);
        mbr_ct = (const struct ctype*) lua_touserdata(L, -1);

        if (mbr_ct->pointers || mbr_ct->is_reference) {
            lua_getuservalue(L, -1);
            num_upvals += 2;
            dasm_put(Dst, 1278, mbr_ct, lua_upvalueindex(num_upvals), i);
            add_pointer(Dst, ct, &reg);
        } else {
            switch (mbr_ct->type) {
            case FUNCTION_PTR_TYPE:
                lua_getuservalue(L, -1);
                num_upvals += 2;
                dasm_put(Dst, 1301, mbr_ct, lua_upvalueindex(num_upvals), i);
                add_pointer(Dst, ct, &reg);
                break;

            case ENUM_TYPE:
                lua_getuservalue(L, -1);
                num_upvals += 2;
                dasm_put(Dst, 1324, mbr_ct, lua_upvalueindex(num_upvals), i);
                add_int(Dst, ct, &reg, 0);
                break;

            case INT8_TYPE:
                dasm_put(Dst, 1347, i);
                if (mbr_ct->is_unsigned) {
                    dasm_put(Dst, 1360);
                } else {
                    dasm_put(Dst, 1364);
                }
                add_int(Dst, ct, &reg, 0);
                lua_pop(L, 1);
                break;

            case INT16_TYPE:
                dasm_put(Dst, 1347, i);
                if (mbr_ct->is_unsigned) {
                    dasm_put(Dst, 1368);
                } else {
                    dasm_put(Dst, 1372);
                }
                add_int(Dst, ct, &reg, 0);
                lua_pop(L, 1);
                break;

            case BOOL_TYPE:
                dasm_put(Dst, 1376, i);
                add_int(Dst, ct, &reg, 0);
                lua_pop(L, 1);
                break;

            case INT32_TYPE:
                if (mbr_ct->is_unsigned) {
                    dasm_put(Dst, 1399, i);
                } else {
                    dasm_put(Dst, 1347, i);
                }
                add_int(Dst, ct, &reg, 0);
                lua_pop(L, 1);
                break;

            case INTPTR_TYPE:
                dasm_put(Dst, 1412, i);
                add_pointer(Dst, ct, &reg);
                lua_pop(L, 1);
                break;

            case INT64_TYPE:
                if (mbr_ct->is_unsigned) {
                    dasm_put(Dst, 1425, i);
                } else {
                    dasm_put(Dst, 1438, i);
                }
                add_int(Dst, ct, &reg, 1);
                lua_pop(L, 1);
                break;

            case DOUBLE_TYPE:
                dasm_put(Dst, 1451, i);
                add_float(Dst, ct, &reg, 1);
                lua_pop(L, 1);
                break;

            case COMPLEX_DOUBLE_TYPE:
                /* on 64 bit, returned complex doubles use xmm0, xmm1, on 32 bit
                 * there is a hidden first parameter that points to 16 bytes where
                 * the returned arg is stored (this is popped by the called
                 * function) */
#if defined _WIN64 || defined __amd64__
                dasm_put(Dst, 1464, i);
                add_float(Dst, ct, &reg, 1);
                dasm_put(Dst, 1477);
                add_float(Dst, ct, &reg, 1);
#else
                dasm_put(Dst, 1483, reg.off, i);
                reg.off += 16;
#endif
                lua_pop(L, 1);
                break;

            case FLOAT_TYPE:
                dasm_put(Dst, 1451, i);
                add_float(Dst, ct, &reg, 0);
                lua_pop(L, 1);
                break;

            case COMPLEX_FLOAT_TYPE:
#if defined _WIN64 || defined __amd64__
                dasm_put(Dst, 1509, i);
                /* complex floats are two floats packed into a double */
                add_float(Dst, ct, &reg, 1);
#else
                /* returned complex floats use eax and edx */
                dasm_put(Dst, 1522, i);
                add_float(Dst, ct, &reg, 0);
                dasm_put(Dst, 1541);
                add_float(Dst, ct, &reg, 0);
#endif
                lua_pop(L, 1);
                break;

            default:
                luaL_error(L, "NYI: call arg type");
            }
        }
    }

    if (ct->has_var_arg) {
#ifdef _WIN64
        if (reg.regs < MAX_REGISTERS(ct)) {
            assert(reg.regs == nargs);
        } else {
        }

        for (i = nargs; i < MAX_REGISTERS(ct); i++) {
            reg.is_int[i] = reg.is_float[i] = 1;
        }
        reg.regs = MAX_REGISTERS(ct);
#elif defined __amd64__
        if (reg.floats < MAX_FLOAT_REGISTERS(ct)) {
        }

        if (reg.ints < MAX_INT_REGISTERS(ct)) {
        }


        reg.floats = MAX_FLOAT_REGISTERS(ct);
        reg.ints = MAX_INT_REGISTERS(ct);
#else
        dasm_put(Dst, 1548, reg.off, nargs+1);
#endif
    }

    dasm_put(Dst, 1574, perr);

    /* remove the stack space to call local functions */
    dasm_put(Dst, 1586);

#ifdef _WIN64
    switch (reg.regs) {
    case 4:
        if (reg.is_float[3]) {
        }
        if (reg.is_int[3]) {
        }
    case 3:
        if (reg.is_float[2]) {
        }
        if (reg.is_int[2]) {
        }
    case 2:
        if (reg.is_float[1]) {
        }
        if (reg.is_int[1]) {
        }
    case 1:
        if (reg.is_float[0]) {
        }
        if (reg.is_int[0]) {
        }
    case 0:
        break;
    }

    /* don't remove the space for the registers as we need 32 bytes of register overflow space */
    assert(REGISTER_STACK_SPACE(ct) == 32);

#elif defined __amd64__
    switch (reg.floats) {
    case 8:
    case 7:
    case 6:
    case 5:
    case 4:
    case 3:
    case 2:
    case 1:
    case 0:
        break;
    }

    switch (reg.ints) {
    case 6:
    case 5:
    case 4:
    case 3:
    case 2:
    case 1:
    case 0:
        break;
    }

#else
    if (ct->calling_convention == FAST_CALL) {
        switch (reg.ints) {
        case 2:
            dasm_put(Dst, 1590, 4);
        case 1:
            dasm_put(Dst, 1596);
        case 0:
            break;
        }

        dasm_put(Dst, 1600, REGISTER_STACK_SPACE(ct));
    }
#endif

#ifdef __amd64__
    if (ct->has_var_arg) {
        /* al stores an upper limit on the number of float register, note that
         * its allowed to be more than the actual number of float registers used as
         * long as its 0-8 */
    }
#endif

    dasm_put(Dst, 1604);

    /* note on windows X86 the stack may be only aligned to 4 (stdcall will
     * have popped a multiple of 4 bytes), but we don't need 16 byte alignment on
     * that platform
     */

    lua_rawgeti(L, ct_usr, 0);
    mbr_ct = (const struct ctype*) lua_touserdata(L, -1);

    if (mbr_ct->pointers || mbr_ct->is_reference || mbr_ct->type == INTPTR_TYPE) {
        lua_getuservalue(L, -1);
        num_upvals += 2;
        dasm_put(Dst, 1613, perr, mbr_ct, lua_upvalueindex(num_upvals));

    } else {
        switch (mbr_ct->type) {
        case FUNCTION_PTR_TYPE:
            lua_getuservalue(L, -1);
            num_upvals += 2;
            dasm_put(Dst, 1613, perr, mbr_ct, lua_upvalueindex(num_upvals));
            break;

        case INT64_TYPE:
            num_upvals++;
            dasm_put(Dst, 1653, perr, mbr_ct);
            break;

        case COMPLEX_FLOAT_TYPE:
            lua_getuservalue(L, -1);
            num_upvals += 2;
            dasm_put(Dst, 1707, perr, mbr_ct, lua_upvalueindex(num_upvals));
            break;

        case COMPLEX_DOUBLE_TYPE:
            lua_getuservalue(L, -1);
            num_upvals += 2;
            dasm_put(Dst, 1758, perr);
            break;

        case VOID_TYPE:
            lua_pop(L, 1);
            dasm_put(Dst, 1775);
            break;

        case BOOL_TYPE:
            lua_pop(L, 1);
            dasm_put(Dst, 1780);
            break;

        case INT8_TYPE:
            lua_pop(L, 1);
            if (mbr_ct->is_unsigned) {
                dasm_put(Dst, 1360);
            } else {
                dasm_put(Dst, 1364);
            }
            dasm_put(Dst, 1785);
            break;

        case INT16_TYPE:
            lua_pop(L, 1);
            if (mbr_ct->is_unsigned) {
                dasm_put(Dst, 1368);
            } else {
                dasm_put(Dst, 1372);
            }
            dasm_put(Dst, 1785);
            break;

        case INT32_TYPE:
        case ENUM_TYPE:
            lua_pop(L, 1);
            if (mbr_ct->is_unsigned) {
                dasm_put(Dst, 1790);
            } else {
                dasm_put(Dst, 1785);
            }
            break;

        case FLOAT_TYPE:
            lua_pop(L, 1);
            dasm_put(Dst, 1795);
            break;

        case DOUBLE_TYPE:
            lua_pop(L, 1);
            dasm_put(Dst, 1795);
            break;

        default:
            luaL_error(L, "NYI: call return type");
        }
    }

    assert(lua_gettop(L) == top + num_upvals);
    {
        cfunction f = compile(Dst, L, func, LUA_NOREF);
        /* add a callback as an upval so that the jitted code gets cleaned up when
         * the function gets gc'd */
        push_callback(L, f, func);
        lua_pushcclosure(L, (lua_CFunction) f, num_upvals+1);
    }
}