corda/sdk/compiler-rt/muldi3.c
Angie Chinchilla 9441de4c38 Initial release of Intel SGX for Linux.
This release is used in conjunction with the linux-sgx-driver Intial release:
https://github.com/01org/linux-sgx-driver
commit-id: 0e865ce5e6b297a787bcdc12d98bada8174be6d7

Intel-id: 33399

Signed-off-by: Angie Chinchilla <angie.v.chinchilla@intel.com>
2016-06-23 18:51:53 -04:00

57 lines
1.5 KiB
C

/* ===-- muldi3.c - Implement __muldi3 -------------------------------------===
*
* The LLVM Compiler Infrastructure
*
* This file is dual licensed under the MIT and the University of Illinois Open
* Source Licenses. See LICENSE.TXT for details.
*
* ===----------------------------------------------------------------------===
*
* This file implements __muldi3 for the compiler_rt library.
*
* ===----------------------------------------------------------------------===
*/
#include "int_lib.h"
/* Returns: a * b */
static
di_int
__muldsi3(su_int a, su_int b)
{
dwords r;
const int bits_in_word_2 = (int)(sizeof(si_int) * CHAR_BIT) / 2;
const su_int lower_mask = (su_int)~0 >> bits_in_word_2;
r.s.low = (a & lower_mask) * (b & lower_mask);
su_int t = r.s.low >> bits_in_word_2;
r.s.low &= lower_mask;
t += (a >> bits_in_word_2) * (b & lower_mask);
r.s.low += (t & lower_mask) << bits_in_word_2;
r.s.high = t >> bits_in_word_2;
t = r.s.low >> bits_in_word_2;
r.s.low &= lower_mask;
t += (b >> bits_in_word_2) * (a & lower_mask);
r.s.low += (t & lower_mask) << bits_in_word_2;
r.s.high += t >> bits_in_word_2;
r.s.high += (a >> bits_in_word_2) * (b >> bits_in_word_2);
return r.all;
}
/* Returns: a * b */
ARM_EABI_FNALIAS(lmul, muldi3)
COMPILER_RT_ABI di_int
__muldi3(di_int a, di_int b)
{
dwords x;
x.all = a;
dwords y;
y.all = b;
dwords r;
r.all = __muldsi3(x.s.low, y.s.low);
r.s.high += x.s.high * y.s.low + x.s.low * y.s.high;
return r.all;
}