1
Fork 0
mirror of https://git.savannah.gnu.org/git/guile.git synced 2025-05-29 16:30:19 +02:00
guile/libguile/lightening/lightening/arm.c

139 lines
3.2 KiB
C

/*
* Copyright (C) 2012-2019 Free Software Foundation, Inc.
*
* This file is part of GNU lightning.
*
* GNU lightning is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 3, or (at your option)
* any later version.
*
* GNU lightning is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* Authors:
* Paulo Cesar Pereira de Andrade
*/
/*
* Types
*/
typedef union _jit_thumb_t {
int32_t i;
int16_t s[2];
} jit_thumb_t;
/* libgcc */
extern void __clear_cache(void *, void *);
#include "arm-cpu.c"
#include "arm-vfp.c"
static const jit_gpr_t abi_gpr_args[] = {
_R0, _R1, _R2, _R3
};
static const int abi_gpr_arg_count = sizeof(abi_gpr_args) / sizeof(abi_gpr_args[0]);
struct abi_arg_iterator
{
const jit_operand_t *args;
size_t argc;
size_t arg_idx;
size_t gpr_idx;
uint32_t vfp_used_registers;
size_t stack_size;
size_t stack_padding;
};
static size_t page_size;
jit_bool_t
jit_get_cpu(void)
{
page_size = sysconf(_SC_PAGE_SIZE);
// FIXME check version, thumb, hardware fp support
return 1;
}
jit_bool_t
jit_init(jit_state_t *_jit)
{
return 1;
}
static size_t
jit_initial_frame_size (void)
{
return 0;
}
static void
reset_abi_arg_iterator(struct abi_arg_iterator *iter, size_t argc,
const jit_operand_t *args)
{
memset(iter, 0, sizeof *iter);
iter->argc = argc;
iter->args = args;
}
static void
next_abi_arg(struct abi_arg_iterator *iter, jit_operand_t *arg)
{
ASSERT(iter->arg_idx < iter->argc);
enum jit_operand_abi abi = iter->args[iter->arg_idx].abi;
iter->arg_idx++;
if (is_gpr_arg(abi) && iter->gpr_idx < abi_gpr_arg_count) {
*arg = jit_operand_gpr (abi, abi_gpr_args[iter->gpr_idx++]);
return;
}
if (is_fpr_arg(abi)) {
// The ARM VFP ABI passes floating-point arguments in d0-d7
// (s0-s15), and allows for "back-filling". Say you have a
// function:
//
// void f(float a, double b, float c);
//
// A gets allocated to s0, then b to d1 (which aliases s2+s3), then
// c to s1.
uint32_t width = abi == JIT_OPERAND_ABI_FLOAT ? 1 : 2;
uint32_t mask = (1 << width) - 1;
for (size_t i = 0; i < 16; i += width) {
if ((iter->vfp_used_registers & (mask << i)) == 0) {
iter->vfp_used_registers |= (mask << i);
*arg = jit_operand_fpr (abi, JIT_FPR(i));
return;
}
}
}
*arg = jit_operand_mem (abi, JIT_SP, iter->stack_size);
iter->stack_size += 4;
}
static void
jit_flush(void *fptr, void *tptr)
{
jit_word_t f = (jit_word_t)fptr & -page_size;
jit_word_t t = (((jit_word_t)tptr) + page_size - 1) & -page_size;
__clear_cache((void *)f, (void *)t);
}
static inline size_t
jit_stack_alignment(void)
{
return 8;
}
static void
jit_try_shorten(jit_state_t *_jit, jit_reloc_t reloc, jit_pointer_t addr)
{
}
static void*
bless_function_pointer(void *ptr)
{
// Set low bit to mark as thumb mode.
return (void*) (((uintptr_t)ptr) | 1);
}