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      1 // SPDX-License-Identifier: GPL-2.0+
      2 /*
      3  * U-Boot - muldi3.c contains routines for mult and div
      4  *
      5  */
      6 
      7 /* Generic function got from GNU gcc package, libgcc2.c */
      8 #ifndef SI_TYPE_SIZE
      9 #define SI_TYPE_SIZE 32
     10 #endif
     11 #define __ll_B (1L << (SI_TYPE_SIZE / 2))
     12 #define __ll_lowpart(t) ((USItype) (t) % __ll_B)
     13 #define __ll_highpart(t) ((USItype) (t) / __ll_B)
     14 #define BITS_PER_UNIT 8
     15 
     16 #if !defined(umul_ppmm)
     17 #define umul_ppmm(w1, w0, u, v)						\
     18 	do {								\
     19 	USItype __x0, __x1, __x2, __x3;					\
     20 	USItype __ul, __vl, __uh, __vh;					\
     21 									\
     22 		__ul = __ll_lowpart(u);					\
     23 		__uh = __ll_highpart(u);				\
     24 		__vl = __ll_lowpart(v);					\
     25 		__vh = __ll_highpart(v);				\
     26 									\
     27 	__x0 = (USItype) __ul * __vl;					\
     28 	__x1 = (USItype) __ul * __vh;					\
     29 	__x2 = (USItype) __uh * __vl;					\
     30 	__x3 = (USItype) __uh * __vh;					\
     31 									\
     32 		__x1 += __ll_highpart(__x0); /* this can't give carry */\
     33 		__x1 += __x2; /* but this indeed can */			\
     34 		if (__x1 < __x2) /* did we get it? */			\
     35 		__x3 += __ll_B;	/* yes, add it in the proper pos. */	\
     36 									\
     37 		(w1) = __x3 + __ll_highpart(__x1);			\
     38 		(w0) = __ll_lowpart(__x1) * __ll_B + __ll_lowpart(__x0);\
     39 	} while (0)
     40 #endif
     41 
     42 #if !defined(__umulsidi3)
     43 #define __umulsidi3(u, v)						\
     44 	({DIunion __w;							\
     45 	umul_ppmm(__w.s.high, __w.s.low, u, v);		\
     46 	__w.ll; })
     47 #endif
     48 
     49 typedef unsigned int USItype __attribute__ ((mode(SI)));
     50 typedef int SItype __attribute__ ((mode(SI)));
     51 typedef int DItype __attribute__ ((mode(DI)));
     52 typedef int word_type __attribute__ ((mode(__word__)));
     53 
     54 struct DIstruct {
     55 	SItype low, high;
     56 };
     57 typedef union {
     58 	struct DIstruct s;
     59 	DItype ll;
     60 } DIunion;
     61 
     62 DItype __muldi3(DItype u, DItype v)
     63 {
     64 	DIunion w;
     65 	DIunion uu, vv;
     66 
     67 	uu.ll = u, vv.ll = v;
     68 	/*  panic("kernel panic for __muldi3"); */
     69 	w.ll = __umulsidi3(uu.s.low, vv.s.low);
     70 	w.s.high += ((USItype) uu.s.low * (USItype) vv.s.high
     71 		     + (USItype) uu.s.high * (USItype) vv.s.low);
     72 
     73 	return w.ll;
     74 }
     75