diff options
author | Thomas Gleixner <tglx@linutronix.de> | 2007-10-11 05:20:03 -0400 |
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committer | Thomas Gleixner <tglx@linutronix.de> | 2007-10-11 05:20:03 -0400 |
commit | 96a388de5dc53a8b234b3fd41f3ae2cedc9ffd42 (patch) | |
tree | d947a467aa2da3140279617bc4b9b101640d7bf4 /include/asm-x86/div64_32.h | |
parent | 27bd0c955648646abf2a353a8371d28c37bcd982 (diff) |
i386/x86_64: move headers to include/asm-x86
Move the headers to include/asm-x86 and fixup the
header install make rules
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'include/asm-x86/div64_32.h')
-rw-r--r-- | include/asm-x86/div64_32.h | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/include/asm-x86/div64_32.h b/include/asm-x86/div64_32.h new file mode 100644 index 000000000000..438e980068bd --- /dev/null +++ b/include/asm-x86/div64_32.h | |||
@@ -0,0 +1,52 @@ | |||
1 | #ifndef __I386_DIV64 | ||
2 | #define __I386_DIV64 | ||
3 | |||
4 | #include <linux/types.h> | ||
5 | |||
6 | /* | ||
7 | * do_div() is NOT a C function. It wants to return | ||
8 | * two values (the quotient and the remainder), but | ||
9 | * since that doesn't work very well in C, what it | ||
10 | * does is: | ||
11 | * | ||
12 | * - modifies the 64-bit dividend _in_place_ | ||
13 | * - returns the 32-bit remainder | ||
14 | * | ||
15 | * This ends up being the most efficient "calling | ||
16 | * convention" on x86. | ||
17 | */ | ||
18 | #define do_div(n,base) ({ \ | ||
19 | unsigned long __upper, __low, __high, __mod, __base; \ | ||
20 | __base = (base); \ | ||
21 | asm("":"=a" (__low), "=d" (__high):"A" (n)); \ | ||
22 | __upper = __high; \ | ||
23 | if (__high) { \ | ||
24 | __upper = __high % (__base); \ | ||
25 | __high = __high / (__base); \ | ||
26 | } \ | ||
27 | asm("divl %2":"=a" (__low), "=d" (__mod):"rm" (__base), "0" (__low), "1" (__upper)); \ | ||
28 | asm("":"=A" (n):"a" (__low),"d" (__high)); \ | ||
29 | __mod; \ | ||
30 | }) | ||
31 | |||
32 | /* | ||
33 | * (long)X = ((long long)divs) / (long)div | ||
34 | * (long)rem = ((long long)divs) % (long)div | ||
35 | * | ||
36 | * Warning, this will do an exception if X overflows. | ||
37 | */ | ||
38 | #define div_long_long_rem(a,b,c) div_ll_X_l_rem(a,b,c) | ||
39 | |||
40 | static inline long | ||
41 | div_ll_X_l_rem(long long divs, long div, long *rem) | ||
42 | { | ||
43 | long dum2; | ||
44 | __asm__("divl %2":"=a"(dum2), "=d"(*rem) | ||
45 | : "rm"(div), "A"(divs)); | ||
46 | |||
47 | return dum2; | ||
48 | |||
49 | } | ||
50 | |||
51 | extern uint64_t div64_64(uint64_t dividend, uint64_t divisor); | ||
52 | #endif | ||