arch/sparc/math-emu/sfp-util_32.h

Source file repositories/reference/linux-study-clean/arch/sparc/math-emu/sfp-util_32.h

File Facts

System
Linux kernel
Corpus path
arch/sparc/math-emu/sfp-util_32.h
Extension
.h
Size
3778 bytes
Lines
117
Domain
Architecture Layer
Bucket
arch/sparc
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

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <asm/byteorder.h>

#define add_ssaaaa(sh, sl, ah, al, bh, bl) 				\
  __asm__ ("addcc %r4,%5,%1\n\t"					\
	   "addx %r2,%3,%0\n"						\
	   : "=r" (sh),							\
	     "=&r" (sl)							\
	   : "%rJ" ((USItype)(ah)),					\
	     "rI" ((USItype)(bh)),					\
	     "%rJ" ((USItype)(al)),					\
	     "rI" ((USItype)(bl))					\
	   : "cc")
#define sub_ddmmss(sh, sl, ah, al, bh, bl) 				\
  __asm__ ("subcc %r4,%5,%1\n\t"					\
	   "subx %r2,%3,%0\n"						\
	   : "=r" (sh),							\
	     "=&r" (sl)							\
	   : "rJ" ((USItype)(ah)),					\
	     "rI" ((USItype)(bh)),					\
	     "rJ" ((USItype)(al)),					\
	     "rI" ((USItype)(bl))					\
	   : "cc")

#define umul_ppmm(w1, w0, u, v) \
  __asm__ ("! Inlined umul_ppmm\n\t"					\
	"wr	%%g0,%2,%%y	! SPARC has 0-3 delay insn after a wr\n\t" \
	"sra	%3,31,%%g2	! Don't move this insn\n\t"		\
	"and	%2,%%g2,%%g2	! Don't move this insn\n\t"		\
	"andcc	%%g0,0,%%g1	! Don't move this insn\n\t"		\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,%3,%%g1\n\t"					\
	"mulscc	%%g1,0,%%g1\n\t" 					\
	"add	%%g1,%%g2,%0\n\t" 					\
	"rd	%%y,%1\n"						\
	   : "=r" (w1),							\
	     "=r" (w0)							\
	   : "%rI" ((USItype)(u)),					\
	     "r" ((USItype)(v))						\
	   : "%g1", "%g2", "cc")

/* It's quite necessary to add this much assembler for the sparc.
   The default udiv_qrnnd (in C) is more than 10 times slower!  */
#define udiv_qrnnd(q, r, n1, n0, d) \
  __asm__ ("! Inlined udiv_qrnnd\n\t"					\
	   "mov	32,%%g1\n\t"						\
	   "subcc	%1,%2,%%g0\n\t"					\
	   "1:	bcs	5f\n\t"						\
	   "addxcc %0,%0,%0	! shift n1n0 and a q-bit in lsb\n\t"	\
	   "sub	%1,%2,%1	! this kills msb of n\n\t"		\
	   "addx	%1,%1,%1	! so this can't give carry\n\t"	\
	   "subcc	%%g1,1,%%g1\n\t"				\
	   "2:	bne	1b\n\t"						\
	   "subcc	%1,%2,%%g0\n\t"					\
	   "bcs	3f\n\t"							\
	   "addxcc %0,%0,%0	! shift n1n0 and a q-bit in lsb\n\t"	\
	   "b		3f\n\t"						\
	   "sub	%1,%2,%1	! this kills msb of n\n\t"		\

Annotation

Implementation Notes