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kernel/linux-rt-4.4.41/arch/h8300/lib/muldi3.c 1.14 KB
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  #include "libgcc.h"
  
  #define __ll_B ((UWtype) 1 << (W_TYPE_SIZE / 2))
  #define __ll_lowpart(t) ((UWtype) (t) & (__ll_B - 1))
  #define __ll_highpart(t) ((UWtype) (t) >> (W_TYPE_SIZE / 2))
  
  #define umul_ppmm(w1, w0, u, v) \
  	do {			   \
  		UWtype __x0, __x1, __x2, __x3;	\
  		UHWtype __ul, __vl, __uh, __vh; \
  		__ul = __ll_lowpart(u);	\
  		__uh = __ll_highpart(u);	\
  		__vl = __ll_lowpart(v);	\
  		__vh = __ll_highpart(v);	\
  		__x0 = (UWtype) __ul * __vl;	\
  		__x1 = (UWtype) __ul * __vh;	\
  		__x2 = (UWtype) __uh * __vl;	\
  		__x3 = (UWtype) __uh * __vh;	\
  		__x1 += __ll_highpart(__x0);	\
  		__x1 += __x2;			\
  		if (__x1 < __x2)		\
  			__x3 += __ll_B;		\
  		(w1) = __x3 + __ll_highpart(__x1);	       \
  		(w0) = __ll_lowpart(__x1) * __ll_B + __ll_lowpart(__x0); \
  	} while (0)
  
  #define __umulsidi3(u, v) (			\
  		{				\
  			DWunion __w;		\
  			umul_ppmm(__w.s.high, __w.s.low, u, v);	\
  			__w.ll; }					\
  		)
  
  DWtype __muldi3(DWtype u, DWtype v)
  {
  	const DWunion uu = {.ll = u};
  	const DWunion vv = {.ll = v};
  	DWunion w = {.ll = __umulsidi3(uu.s.low, vv.s.low)};
  
  	w.s.high += ((UWtype) uu.s.low * (UWtype) vv.s.high
  		     + (UWtype) uu.s.high * (UWtype) vv.s.low);
  
  	return w.ll;
  }