mirror of
https://github.com/Atmosphere-NX/Atmosphere.git
synced 2024-12-27 12:46:03 +00:00
260 lines
No EOL
6.4 KiB
C
260 lines
No EOL
6.4 KiB
C
// SPDX-License-Identifier: BSD-2-Clause
|
|
/*
|
|
* Copyright (c) 2014, STMicroelectronics International N.V.
|
|
*/
|
|
|
|
/*
|
|
* Form ABI specifications:
|
|
* int __aeabi_idiv(int numerator, int denominator);
|
|
* unsigned __aeabi_uidiv(unsigned numerator, unsigned denominator);
|
|
*
|
|
* typedef struct { int quot; int rem; } idiv_return;
|
|
* typedef struct { unsigned quot; unsigned rem; } uidiv_return;
|
|
*
|
|
* __value_in_regs idiv_return __aeabi_idivmod(int numerator,
|
|
* int *denominator);
|
|
* __value_in_regs uidiv_return __aeabi_uidivmod(unsigned *numerator,
|
|
* unsigned denominator);
|
|
*/
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
|
|
/* struct qr - stores qutient/remainder to handle divmod EABI interfaces. */
|
|
struct qr {
|
|
unsigned q; /* computed quotient */
|
|
unsigned r; /* computed remainder */
|
|
unsigned q_n; /* specficies if quotient shall be negative */
|
|
unsigned r_n; /* specficies if remainder shall be negative */
|
|
};
|
|
|
|
static void uint_div_qr(unsigned numerator, unsigned denominator,
|
|
struct qr *qr);
|
|
|
|
/* returns in R0 and R1 by tail calling an asm function */
|
|
unsigned __aeabi_uidivmod(unsigned numerator, unsigned denominator);
|
|
|
|
unsigned __aeabi_uidiv(unsigned numerator, unsigned denominator);
|
|
|
|
/* returns in R0 and R1 by tail calling an asm function */
|
|
signed __aeabi_idivmod(signed numerator, signed denominator);
|
|
|
|
signed __aeabi_idiv(signed numerator, signed denominator);
|
|
|
|
/*
|
|
* __ste_idivmod_ret_t __aeabi_idivmod(signed numerator, signed denominator)
|
|
* Numerator and Denominator are received in R0 and R1.
|
|
* Where __ste_idivmod_ret_t is returned in R0 and R1.
|
|
*
|
|
* __ste_uidivmod_ret_t __aeabi_uidivmod(unsigned numerator,
|
|
* unsigned denominator)
|
|
* Numerator and Denominator are received in R0 and R1.
|
|
* Where __ste_uidivmod_ret_t is returned in R0 and R1.
|
|
*/
|
|
#ifdef __GNUC__
|
|
signed ret_idivmod_values(signed quotient, signed remainder);
|
|
unsigned ret_uidivmod_values(unsigned quotient, unsigned remainder);
|
|
#else
|
|
#error "Compiler not supported"
|
|
#endif
|
|
|
|
static void division_qr(unsigned n, unsigned p, struct qr *qr)
|
|
{
|
|
unsigned i = 1, q = 0;
|
|
if (p == 0) {
|
|
qr->r = 0xFFFFFFFF; /* division by 0 */
|
|
return;
|
|
}
|
|
|
|
while ((p >> 31) == 0) {
|
|
i = i << 1; /* count the max division steps */
|
|
p = p << 1; /* increase p until it has maximum size*/
|
|
}
|
|
|
|
while (i > 0) {
|
|
q = q << 1; /* write bit in q at index (size-1) */
|
|
if (n >= p)
|
|
{
|
|
n -= p;
|
|
q++;
|
|
}
|
|
p = p >> 1; /* decrease p */
|
|
i = i >> 1; /* decrease remaining size in q */
|
|
}
|
|
qr->r = n;
|
|
qr->q = q;
|
|
}
|
|
|
|
static void uint_div_qr(unsigned numerator, unsigned denominator, struct qr *qr)
|
|
{
|
|
|
|
division_qr(numerator, denominator, qr);
|
|
|
|
/* negate quotient and/or remainder according to requester */
|
|
if (qr->q_n)
|
|
qr->q = -qr->q;
|
|
if (qr->r_n)
|
|
qr->r = -qr->r;
|
|
}
|
|
|
|
unsigned __aeabi_uidiv(unsigned numerator, unsigned denominator)
|
|
{
|
|
struct qr qr = { .q_n = 0, .r_n = 0 };
|
|
|
|
uint_div_qr(numerator, denominator, &qr);
|
|
|
|
return qr.q;
|
|
}
|
|
|
|
unsigned __aeabi_uidivmod(unsigned numerator, unsigned denominator)
|
|
{
|
|
struct qr qr = { .q_n = 0, .r_n = 0 };
|
|
|
|
uint_div_qr(numerator, denominator, &qr);
|
|
|
|
return ret_uidivmod_values(qr.q, qr.r);
|
|
}
|
|
|
|
signed __aeabi_idiv(signed numerator, signed denominator)
|
|
{
|
|
struct qr qr = { .q_n = 0, .r_n = 0 };
|
|
|
|
if (((numerator < 0) && (denominator > 0)) ||
|
|
((numerator > 0) && (denominator < 0)))
|
|
qr.q_n = 1; /* quotient shall be negate */
|
|
if (numerator < 0) {
|
|
numerator = -numerator;
|
|
qr.r_n = 1; /* remainder shall be negate */
|
|
}
|
|
if (denominator < 0)
|
|
denominator = -denominator;
|
|
|
|
uint_div_qr(numerator, denominator, &qr);
|
|
|
|
return qr.q;
|
|
}
|
|
|
|
signed __aeabi_idivmod(signed numerator, signed denominator)
|
|
{
|
|
struct qr qr = { .q_n = 0, .r_n = 0 };
|
|
|
|
if (((numerator < 0) && (denominator > 0)) ||
|
|
((numerator > 0) && (denominator < 0)))
|
|
qr.q_n = 1; /* quotient shall be negate */
|
|
if (numerator < 0) {
|
|
numerator = -numerator;
|
|
qr.r_n = 1; /* remainder shall be negate */
|
|
}
|
|
if (denominator < 0)
|
|
denominator = -denominator;
|
|
|
|
uint_div_qr(numerator, denominator, &qr);
|
|
|
|
return ret_idivmod_values(qr.q, qr.r);
|
|
}
|
|
|
|
/* struct lqr - stores qutient/remainder to handle divmod EABI interfaces. */
|
|
struct lqr {
|
|
unsigned long long q; /* computed quotient */
|
|
unsigned long long r; /* computed remainder */
|
|
unsigned q_n; /* specficies if quotient shall be negative */
|
|
unsigned r_n; /* specficies if remainder shall be negative */
|
|
};
|
|
|
|
static void ul_div_qr(unsigned long long numerator,
|
|
unsigned long long denominator, struct lqr *qr);
|
|
|
|
|
|
static void division_lqr(unsigned long long n, unsigned long long p,
|
|
struct lqr *qr)
|
|
{
|
|
unsigned long long i = 1, q = 0;
|
|
if (p == 0) {
|
|
qr->r = 0xFFFFFFFFFFFFFFFFULL; /* division by 0 */
|
|
return;
|
|
}
|
|
|
|
while ((p >> 63) == 0) {
|
|
i = i << 1; /* count the max division steps */
|
|
p = p << 1; /* increase p until it has maximum size*/
|
|
}
|
|
|
|
while (i > 0) {
|
|
q = q << 1; /* write bit in q at index (size-1) */
|
|
if (n >= p) {
|
|
n -= p;
|
|
q++;
|
|
}
|
|
p = p >> 1; /* decrease p */
|
|
i = i >> 1; /* decrease remaining size in q */
|
|
}
|
|
qr->r = n;
|
|
qr->q = q;
|
|
}
|
|
|
|
static void ul_div_qr(unsigned long long numerator,
|
|
unsigned long long denominator, struct lqr *qr)
|
|
{
|
|
|
|
division_lqr(numerator, denominator, qr);
|
|
|
|
/* negate quotient and/or remainder according to requester */
|
|
if (qr->q_n)
|
|
qr->q = -qr->q;
|
|
if (qr->r_n)
|
|
qr->r = -qr->r;
|
|
}
|
|
|
|
struct asm_ulqr {
|
|
unsigned long long v0;
|
|
unsigned long long v1;
|
|
};
|
|
|
|
/* called from assembly function __aeabi_uldivmod */
|
|
void __ul_divmod(struct asm_ulqr *asm_ulqr);
|
|
void __ul_divmod(struct asm_ulqr *asm_ulqr)
|
|
{
|
|
unsigned long long numerator = asm_ulqr->v0;
|
|
unsigned long long denominator = asm_ulqr->v1;
|
|
struct lqr qr = { .q_n = 0, .r_n = 0 };
|
|
|
|
ul_div_qr(numerator, denominator, &qr);
|
|
|
|
asm_ulqr->v0 = qr.q;
|
|
asm_ulqr->v1 = qr.r;
|
|
}
|
|
|
|
struct asm_lqr {
|
|
long long v0;
|
|
long long v1;
|
|
};
|
|
|
|
/* called from assembly function __aeabi_ldivmod */
|
|
void __l_divmod(struct asm_lqr *asm_lqr);
|
|
void __l_divmod(struct asm_lqr *asm_lqr)
|
|
{
|
|
long long numerator = asm_lqr->v0;
|
|
long long denominator = asm_lqr->v1;
|
|
struct lqr qr = { .q_n = 0, .r_n = 0 };
|
|
|
|
if (((numerator < 0) && (denominator > 0)) ||
|
|
((numerator > 0) && (denominator < 0)))
|
|
qr.q_n = 1; /* quotient shall be negate */
|
|
if (numerator < 0) {
|
|
numerator = -numerator;
|
|
qr.r_n = 1; /* remainder shall be negate */
|
|
}
|
|
if (denominator < 0)
|
|
denominator = -denominator;
|
|
|
|
ul_div_qr(numerator, denominator, &qr);
|
|
|
|
asm_lqr->v0 = qr.q;
|
|
asm_lqr->v1 = qr.r;
|
|
}
|
|
|
|
#ifdef __cplusplus
|
|
} /* extern "C" */
|
|
#endif |