1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768 |
- /* SPDX-License-Identifier: GPL-2.0-or-later WITH GCC-exception-2.0 */
- #include <linux/linkage.h>
- #include <asm/asmmacro.h>
- #include <asm/core.h>
- ENTRY(__udivsi3)
- abi_entry_default
- #if XCHAL_HAVE_DIV32
- quou a2, a2, a3
- #else
- bltui a3, 2, .Lle_one /* check if the divisor <= 1 */
- mov a6, a2 /* keep dividend in a6 */
- do_nsau a5, a6, a2, a7 /* dividend_shift = nsau (dividend) */
- do_nsau a4, a3, a2, a7 /* divisor_shift = nsau (divisor) */
- bgeu a5, a4, .Lspecial
- sub a4, a4, a5 /* count = divisor_shift - dividend_shift */
- ssl a4
- sll a3, a3 /* divisor <<= count */
- movi a2, 0 /* quotient = 0 */
- /* test-subtract-and-shift loop; one quotient bit on each iteration */
- #if XCHAL_HAVE_LOOPS
- loopnez a4, .Lloopend
- #endif /* XCHAL_HAVE_LOOPS */
- .Lloop:
- bltu a6, a3, .Lzerobit
- sub a6, a6, a3
- addi a2, a2, 1
- .Lzerobit:
- slli a2, a2, 1
- srli a3, a3, 1
- #if !XCHAL_HAVE_LOOPS
- addi a4, a4, -1
- bnez a4, .Lloop
- #endif /* !XCHAL_HAVE_LOOPS */
- .Lloopend:
- bltu a6, a3, .Lreturn
- addi a2, a2, 1 /* increment quotient if dividend >= divisor */
- .Lreturn:
- abi_ret_default
- .Lle_one:
- beqz a3, .Lerror /* if divisor == 1, return the dividend */
- abi_ret_default
- .Lspecial:
- /* return dividend >= divisor */
- bltu a6, a3, .Lreturn0
- movi a2, 1
- abi_ret_default
- .Lerror:
- /* Divide by zero: Use an illegal instruction to force an exception.
- The subsequent "DIV0" string can be recognized by the exception
- handler to identify the real cause of the exception. */
- ill
- .ascii "DIV0"
- .Lreturn0:
- movi a2, 0
- #endif /* XCHAL_HAVE_DIV32 */
- abi_ret_default
- ENDPROC(__udivsi3)
|