arch/sh/math-emu/sfp-util.h

Source file repositories/reference/linux-study-clean/arch/sh/math-emu/sfp-util.h

File Facts

System
Linux kernel
Corpus path
arch/sh/math-emu/sfp-util.h
Extension
.h
Size
2421 bytes
Lines
70
Domain
Architecture Layer
Bucket
arch/sh
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
  do {                                                                  \
    UWtype __x;                                                         \
    __x = (al) + (bl);                                                  \
    (sh) = (ah) + (bh) + (__x < (al));                                  \
    (sl) = __x;                                                         \
  } while (0)

#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
  do {                                                                  \
    UWtype __x;                                                         \
    __x = (al) - (bl);                                                  \
    (sh) = (ah) - (bh) - (__x > (al));                                  \
    (sl) = __x;                                                         \
  } while (0)

#define umul_ppmm(w1, w0, u, v) \
  __asm__ ("dmulu.l %2,%3\n\tsts    macl,%1\n\tsts  mach,%0"	\
	: "=r" ((u32)(w1)), "=r" ((u32)(w0))	\
	:  "r" ((u32)(u)),   "r" ((u32)(v))	\
	: "macl", "mach")

#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 udiv_qrnnd(q, r, n1, n0, d) \
  do {									\
    UWtype __d1, __d0, __q1, __q0;					\
    UWtype __r1, __r0, __m;						\
    __d1 = __ll_highpart (d);						\
    __d0 = __ll_lowpart (d);						\
									\
    __r1 = (n1) % __d1;							\
    __q1 = (n1) / __d1;							\
    __m = (UWtype) __q1 * __d0;						\
    __r1 = __r1 * __ll_B | __ll_highpart (n0);				\
    if (__r1 < __m)							\
      {									\
	__q1--, __r1 += (d);						\
	if (__r1 >= (d)) /* i.e. we didn't get carry when adding to __r1 */\
	  if (__r1 < __m)						\
	    __q1--, __r1 += (d);					\
      }									\
    __r1 -= __m;							\
									\
    __r0 = __r1 % __d1;							\
    __q0 = __r1 / __d1;							\
    __m = (UWtype) __q0 * __d0;						\
    __r0 = __r0 * __ll_B | __ll_lowpart (n0);				\
    if (__r0 < __m)							\
      {									\
	__q0--, __r0 += (d);						\
	if (__r0 >= (d))						\
	  if (__r0 < __m)						\
	    __q0--, __r0 += (d);					\
      }									\
    __r0 -= __m;							\
									\
    (q) = (UWtype) __q1 * __ll_B | __q0;				\
    (r) = __r0;								\
  } while (0)

#define abort()	return 0

Annotation

Implementation Notes