1 /* SPDX-License-Identifier: GPL-2.0-or-later W
2 #include <linux/linkage.h>
3 #include <asm/asmmacro.h>
4 #include <asm/core.h>
5
6 ENTRY(__divsi3)
7
8 abi_entry_default
9 #if XCHAL_HAVE_DIV32
10 quos a2, a2, a3
11 #else
12 xor a7, a2, a3 /* sign = divi
13 do_abs a6, a2, a4 /* udividend =
14 do_abs a3, a3, a4 /* udivisor =
15 bltui a3, 2, .Lle_one /* check if ud
16 do_nsau a5, a6, a2, a8 /* udividend_s
17 do_nsau a4, a3, a2, a8 /* udivisor_sh
18 bgeu a5, a4, .Lspecial
19
20 sub a4, a4, a5 /* count = udi
21 ssl a4
22 sll a3, a3 /* udivisor <<
23 movi a2, 0 /* quotient =
24
25 /* test-subtract-and-shift loop; one q
26 #if XCHAL_HAVE_LOOPS
27 loopnez a4, .Lloopend
28 #endif /* XCHAL_HAVE_LOOPS */
29 .Lloop:
30 bltu a6, a3, .Lzerobit
31 sub a6, a6, a3
32 addi a2, a2, 1
33 .Lzerobit:
34 slli a2, a2, 1
35 srli a3, a3, 1
36 #if !XCHAL_HAVE_LOOPS
37 addi a4, a4, -1
38 bnez a4, .Lloop
39 #endif /* !XCHAL_HAVE_LOOPS */
40 .Lloopend:
41
42 bltu a6, a3, .Lreturn
43 addi a2, a2, 1 /* increment i
44 .Lreturn:
45 neg a5, a2
46 movltz a2, a5, a7 /* return (sig
47 abi_ret_default
48
49 .Lle_one:
50 beqz a3, .Lerror
51 neg a2, a6 /* if udivisor
52 movgez a2, a6, a7 /* (sign < 0)
53 abi_ret_default
54
55 .Lspecial:
56 bltu a6, a3, .Lreturn0 /* if divide
57 movi a2, 1
58 movi a4, -1
59 movltz a2, a4, a7 /* else return
60 abi_ret_default
61
62 .Lerror:
63 /* Divide by zero: Use an illegal inst
64 The subsequent "DIV0" string can be
65 handler to identify the real cause
66 ill
67 .ascii "DIV0"
68
69 .Lreturn0:
70 movi a2, 0
71 #endif /* XCHAL_HAVE_DIV32 */
72 abi_ret_default
73
74 ENDPROC(__divsi3)
75 EXPORT_SYMBOL(__divsi3)
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.