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	As synchronous exceptions really only make sense against the current task (otherwise how are you synchronous) remove the task parameter from from force_sig_fault to make it explicit that is what is going on. The two known exceptions that deliver a synchronous exception to a stopped ptraced task have already been changed to force_sig_fault_to_task. The callers have been changed with the following emacs regular expression (with obvious variations on the architectures that take more arguments) to avoid typos: force_sig_fault[(]\([^,]+\)[,]\([^,]+\)[,]\([^,]+\)[,]\W+current[)] -> force_sig_fault(\1,\2,\3) Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
		
			
				
	
	
		
			609 lines
		
	
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			609 lines
		
	
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * arch/sh/math-emu/math.c
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 *
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 * Copyright (C) 2006 Takashi YOSHII <takasi-y@ops.dti.ne.jp>
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 *
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 * This file is subject to the terms and conditions of the GNU General Public
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 * License.  See the file "COPYING" in the main directory of this archive
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 * for more details.
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 */
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#include <linux/kernel.h>
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#include <linux/errno.h>
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#include <linux/types.h>
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#include <linux/sched/signal.h>
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#include <linux/signal.h>
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#include <linux/perf_event.h>
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#include <linux/uaccess.h>
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#include <asm/processor.h>
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#include <asm/io.h>
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#include "sfp-util.h"
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#include <math-emu/soft-fp.h>
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#include <math-emu/single.h>
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#include <math-emu/double.h>
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#define	FPUL		(fregs->fpul)
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#define FPSCR		(fregs->fpscr)
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#define FPSCR_RM	(FPSCR&3)
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#define FPSCR_DN	((FPSCR>>18)&1)
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#define FPSCR_PR	((FPSCR>>19)&1)
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#define FPSCR_SZ	((FPSCR>>20)&1)
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#define FPSCR_FR	((FPSCR>>21)&1)
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#define FPSCR_MASK	0x003fffffUL
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#define BANK(n)	(n^(FPSCR_FR?16:0))
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#define FR	((unsigned long*)(fregs->fp_regs))
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#define FR0	(FR[BANK(0)])
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#define FRn	(FR[BANK(n)])
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#define FRm	(FR[BANK(m)])
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#define DR	((unsigned long long*)(fregs->fp_regs))
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#define DRn	(DR[BANK(n)/2])
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#define DRm	(DR[BANK(m)/2])
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#define XREG(n)	(n^16)
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#define XFn	(FR[BANK(XREG(n))])
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#define XFm	(FR[BANK(XREG(m))])
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#define XDn	(DR[BANK(XREG(n))/2])
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#define XDm	(DR[BANK(XREG(m))/2])
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#define R0	(regs->regs[0])
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#define Rn	(regs->regs[n])
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#define Rm	(regs->regs[m])
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#define WRITE(d,a)	({if(put_user(d, (typeof (d)*)a)) return -EFAULT;})
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#define READ(d,a)	({if(get_user(d, (typeof (d)*)a)) return -EFAULT;})
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#define PACK_S(r,f)	FP_PACK_SP(&r,f)
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#define UNPACK_S(f,r)	FP_UNPACK_SP(f,&r)
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#define PACK_D(r,f) \
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	{u32 t[2]; FP_PACK_DP(t,f); ((u32*)&r)[0]=t[1]; ((u32*)&r)[1]=t[0];}
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#define UNPACK_D(f,r) \
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	{u32 t[2]; t[0]=((u32*)&r)[1]; t[1]=((u32*)&r)[0]; FP_UNPACK_DP(f,t);}
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// 2 args instructions.
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#define BOTH_PRmn(op,x) \
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	FP_DECL_EX; if(FPSCR_PR) op(D,x,DRm,DRn); else op(S,x,FRm,FRn);
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#define CMP_X(SZ,R,M,N) do{ \
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	FP_DECL_##SZ(Fm); FP_DECL_##SZ(Fn); \
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	UNPACK_##SZ(Fm, M); UNPACK_##SZ(Fn, N); \
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	FP_CMP_##SZ(R, Fn, Fm, 2); }while(0)
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#define EQ_X(SZ,R,M,N) do{ \
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	FP_DECL_##SZ(Fm); FP_DECL_##SZ(Fn); \
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	UNPACK_##SZ(Fm, M); UNPACK_##SZ(Fn, N); \
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	FP_CMP_EQ_##SZ(R, Fn, Fm); }while(0)
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#define CMP(OP) ({ int r; BOTH_PRmn(OP##_X,r); r; })
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static int
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fcmp_gt(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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	if (CMP(CMP) > 0)
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		regs->sr |= 1;
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	else
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		regs->sr &= ~1;
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	return 0;
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}
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static int
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fcmp_eq(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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	if (CMP(CMP /*EQ*/) == 0)
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		regs->sr |= 1;
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	else
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		regs->sr &= ~1;
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	return 0;
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}
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#define ARITH_X(SZ,OP,M,N) do{ \
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	FP_DECL_##SZ(Fm); FP_DECL_##SZ(Fn); FP_DECL_##SZ(Fr); \
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	UNPACK_##SZ(Fm, M); UNPACK_##SZ(Fn, N); \
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	FP_##OP##_##SZ(Fr, Fn, Fm); \
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	PACK_##SZ(N, Fr); }while(0)
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static int
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fadd(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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	BOTH_PRmn(ARITH_X, ADD);
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	return 0;
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}
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static int
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fsub(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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	BOTH_PRmn(ARITH_X, SUB);
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	return 0;
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}
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static int
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fmul(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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	BOTH_PRmn(ARITH_X, MUL);
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	return 0;
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}
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static int
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fdiv(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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	BOTH_PRmn(ARITH_X, DIV);
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	return 0;
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}
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static int
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fmac(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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	FP_DECL_EX;
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	FP_DECL_S(Fr);
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	FP_DECL_S(Ft);
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	FP_DECL_S(F0);
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	FP_DECL_S(Fm);
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	FP_DECL_S(Fn);
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	UNPACK_S(F0, FR0);
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	UNPACK_S(Fm, FRm);
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	UNPACK_S(Fn, FRn);
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	FP_MUL_S(Ft, Fm, F0);
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	FP_ADD_S(Fr, Fn, Ft);
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	PACK_S(FRn, Fr);
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	return 0;
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}
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// to process fmov's extension (odd n for DR access XD).
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#define FMOV_EXT(x) if(x&1) x+=16-1
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static int
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fmov_idx_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
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	     int n)
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{
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	if (FPSCR_SZ) {
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		FMOV_EXT(n);
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		READ(FRn, Rm + R0 + 4);
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		n++;
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		READ(FRn, Rm + R0);
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	} else {
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		READ(FRn, Rm + R0);
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	}
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	return 0;
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}
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static int
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fmov_mem_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
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	     int n)
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{
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	if (FPSCR_SZ) {
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		FMOV_EXT(n);
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		READ(FRn, Rm + 4);
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		n++;
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		READ(FRn, Rm);
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	} else {
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		READ(FRn, Rm);
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	}
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	return 0;
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}
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static int
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fmov_inc_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
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	     int n)
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{
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	if (FPSCR_SZ) {
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		FMOV_EXT(n);
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		READ(FRn, Rm + 4);
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		n++;
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		READ(FRn, Rm);
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		Rm += 8;
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	} else {
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		READ(FRn, Rm);
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		Rm += 4;
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	}
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	return 0;
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}
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static int
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fmov_reg_idx(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
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	     int n)
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{
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	if (FPSCR_SZ) {
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		FMOV_EXT(m);
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		WRITE(FRm, Rn + R0 + 4);
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		m++;
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		WRITE(FRm, Rn + R0);
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	} else {
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		WRITE(FRm, Rn + R0);
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	}
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	return 0;
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}
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static int
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fmov_reg_mem(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
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	     int n)
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{
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	if (FPSCR_SZ) {
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		FMOV_EXT(m);
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		WRITE(FRm, Rn + 4);
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		m++;
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		WRITE(FRm, Rn);
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	} else {
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		WRITE(FRm, Rn);
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	}
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	return 0;
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}
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static int
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fmov_reg_dec(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
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	     int n)
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{
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	if (FPSCR_SZ) {
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		FMOV_EXT(m);
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		Rn -= 8;
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		WRITE(FRm, Rn + 4);
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		m++;
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		WRITE(FRm, Rn);
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	} else {
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		Rn -= 4;
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		WRITE(FRm, Rn);
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	}
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	return 0;
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}
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static int
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fmov_reg_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
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	     int n)
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{
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	if (FPSCR_SZ) {
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		FMOV_EXT(m);
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		FMOV_EXT(n);
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		DRn = DRm;
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	} else {
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		FRn = FRm;
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	}
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	return 0;
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}
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static int
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fnop_mn(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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	return -EINVAL;
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}
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// 1 arg instructions.
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#define NOTYETn(i) static int i(struct sh_fpu_soft_struct *fregs, int n) \
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	{ printk( #i " not yet done.\n"); return 0; }
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NOTYETn(ftrv)
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NOTYETn(fsqrt)
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NOTYETn(fipr)
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NOTYETn(fsca)
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NOTYETn(fsrra)
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#define EMU_FLOAT_X(SZ,N) do { \
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	FP_DECL_##SZ(Fn); \
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	FP_FROM_INT_##SZ(Fn, FPUL, 32, int); \
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	PACK_##SZ(N, Fn); }while(0)
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static int ffloat(struct sh_fpu_soft_struct *fregs, int n)
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{
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	FP_DECL_EX;
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	if (FPSCR_PR)
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		EMU_FLOAT_X(D, DRn);
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	else
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		EMU_FLOAT_X(S, FRn);
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	return 0;
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}
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#define EMU_FTRC_X(SZ,N) do { \
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	FP_DECL_##SZ(Fn); \
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	UNPACK_##SZ(Fn, N); \
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	FP_TO_INT_##SZ(FPUL, Fn, 32, 1); }while(0)
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static int ftrc(struct sh_fpu_soft_struct *fregs, int n)
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{
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	FP_DECL_EX;
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	if (FPSCR_PR)
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		EMU_FTRC_X(D, DRn);
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	else
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		EMU_FTRC_X(S, FRn);
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	return 0;
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}
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static int fcnvsd(struct sh_fpu_soft_struct *fregs, int n)
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{
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	FP_DECL_EX;
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	FP_DECL_S(Fn);
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	FP_DECL_D(Fr);
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	UNPACK_S(Fn, FPUL);
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	FP_CONV(D, S, 2, 1, Fr, Fn);
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	PACK_D(DRn, Fr);
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	return 0;
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}
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static int fcnvds(struct sh_fpu_soft_struct *fregs, int n)
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{
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	FP_DECL_EX;
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	FP_DECL_D(Fn);
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	FP_DECL_S(Fr);
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	UNPACK_D(Fn, DRn);
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	FP_CONV(S, D, 1, 2, Fr, Fn);
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	PACK_S(FPUL, Fr);
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	return 0;
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}
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static int fxchg(struct sh_fpu_soft_struct *fregs, int flag)
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{
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	FPSCR ^= flag;
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	return 0;
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}
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static int fsts(struct sh_fpu_soft_struct *fregs, int n)
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{
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	FRn = FPUL;
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	return 0;
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}
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static int flds(struct sh_fpu_soft_struct *fregs, int n)
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{
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	FPUL = FRn;
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	return 0;
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}
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static int fneg(struct sh_fpu_soft_struct *fregs, int n)
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{
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	FRn ^= (1 << (_FP_W_TYPE_SIZE - 1));
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	return 0;
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}
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static int fabs(struct sh_fpu_soft_struct *fregs, int n)
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{
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	FRn &= ~(1 << (_FP_W_TYPE_SIZE - 1));
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	return 0;
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}
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static int fld0(struct sh_fpu_soft_struct *fregs, int n)
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{
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	FRn = 0;
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	return 0;
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}
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static int fld1(struct sh_fpu_soft_struct *fregs, int n)
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{
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	FRn = (_FP_EXPBIAS_S << (_FP_FRACBITS_S - 1));
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	return 0;
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}
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static int fnop_n(struct sh_fpu_soft_struct *fregs, int n)
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{
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	return -EINVAL;
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}
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/// Instruction decoders.
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static int id_fxfd(struct sh_fpu_soft_struct *, int);
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static int id_fnxd(struct sh_fpu_soft_struct *, struct pt_regs *, int, int);
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static int (*fnxd[])(struct sh_fpu_soft_struct *, int) = {
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	fsts, flds, ffloat, ftrc, fneg, fabs, fsqrt, fsrra,
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	fld0, fld1, fcnvsd, fcnvds, fnop_n, fnop_n, fipr, id_fxfd
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};
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static int (*fnmx[])(struct sh_fpu_soft_struct *, struct pt_regs *, int, int) = {
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	fadd, fsub, fmul, fdiv, fcmp_eq, fcmp_gt, fmov_idx_reg, fmov_reg_idx,
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	fmov_mem_reg, fmov_inc_reg, fmov_reg_mem, fmov_reg_dec,
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	fmov_reg_reg, id_fnxd, fmac, fnop_mn};
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static int id_fxfd(struct sh_fpu_soft_struct *fregs, int x)
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{
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	const int flag[] = { FPSCR_SZ, FPSCR_PR, FPSCR_FR, 0 };
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	switch (x & 3) {
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	case 3:
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		fxchg(fregs, flag[x >> 2]);
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		break;
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	case 1:
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		ftrv(fregs, x - 1);
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		break;
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	default:
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		fsca(fregs, x);
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	}
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	return 0;
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}
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static int
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id_fnxd(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int x, int n)
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{
 | 
						|
	return (fnxd[x])(fregs, n);
 | 
						|
}
 | 
						|
 | 
						|
static int
 | 
						|
id_fnmx(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, u16 code)
 | 
						|
{
 | 
						|
	int n = (code >> 8) & 0xf, m = (code >> 4) & 0xf, x = code & 0xf;
 | 
						|
	return (fnmx[x])(fregs, regs, m, n);
 | 
						|
}
 | 
						|
 | 
						|
static int
 | 
						|
id_sys(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, u16 code)
 | 
						|
{
 | 
						|
	int n = ((code >> 8) & 0xf);
 | 
						|
	unsigned long *reg = (code & 0x0010) ? &FPUL : &FPSCR;
 | 
						|
 | 
						|
	switch (code & 0xf0ff) {
 | 
						|
	case 0x005a:
 | 
						|
	case 0x006a:
 | 
						|
		Rn = *reg;
 | 
						|
		break;
 | 
						|
	case 0x405a:
 | 
						|
	case 0x406a:
 | 
						|
		*reg = Rn;
 | 
						|
		break;
 | 
						|
	case 0x4052:
 | 
						|
	case 0x4062:
 | 
						|
		Rn -= 4;
 | 
						|
		WRITE(*reg, Rn);
 | 
						|
		break;
 | 
						|
	case 0x4056:
 | 
						|
	case 0x4066:
 | 
						|
		READ(*reg, Rn);
 | 
						|
		Rn += 4;
 | 
						|
		break;
 | 
						|
	default:
 | 
						|
		return -EINVAL;
 | 
						|
	}
 | 
						|
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
static int fpu_emulate(u16 code, struct sh_fpu_soft_struct *fregs, struct pt_regs *regs)
 | 
						|
{
 | 
						|
	if ((code & 0xf000) == 0xf000)
 | 
						|
		return id_fnmx(fregs, regs, code);
 | 
						|
	else
 | 
						|
		return id_sys(fregs, regs, code);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 *	denormal_to_double - Given denormalized float number,
 | 
						|
 *	                     store double float
 | 
						|
 *
 | 
						|
 *	@fpu: Pointer to sh_fpu_soft structure
 | 
						|
 *	@n: Index to FP register
 | 
						|
 */
 | 
						|
static void denormal_to_double(struct sh_fpu_soft_struct *fpu, int n)
 | 
						|
{
 | 
						|
	unsigned long du, dl;
 | 
						|
	unsigned long x = fpu->fpul;
 | 
						|
	int exp = 1023 - 126;
 | 
						|
 | 
						|
	if (x != 0 && (x & 0x7f800000) == 0) {
 | 
						|
		du = (x & 0x80000000);
 | 
						|
		while ((x & 0x00800000) == 0) {
 | 
						|
			x <<= 1;
 | 
						|
			exp--;
 | 
						|
		}
 | 
						|
		x &= 0x007fffff;
 | 
						|
		du |= (exp << 20) | (x >> 3);
 | 
						|
		dl = x << 29;
 | 
						|
 | 
						|
		fpu->fp_regs[n] = du;
 | 
						|
		fpu->fp_regs[n+1] = dl;
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 *	ieee_fpe_handler - Handle denormalized number exception
 | 
						|
 *
 | 
						|
 *	@regs: Pointer to register structure
 | 
						|
 *
 | 
						|
 *	Returns 1 when it's handled (should not cause exception).
 | 
						|
 */
 | 
						|
static int ieee_fpe_handler(struct pt_regs *regs)
 | 
						|
{
 | 
						|
	unsigned short insn = *(unsigned short *)regs->pc;
 | 
						|
	unsigned short finsn;
 | 
						|
	unsigned long nextpc;
 | 
						|
	int nib[4] = {
 | 
						|
		(insn >> 12) & 0xf,
 | 
						|
		(insn >> 8) & 0xf,
 | 
						|
		(insn >> 4) & 0xf,
 | 
						|
		insn & 0xf};
 | 
						|
 | 
						|
	if (nib[0] == 0xb ||
 | 
						|
	    (nib[0] == 0x4 && nib[2] == 0x0 && nib[3] == 0xb)) /* bsr & jsr */
 | 
						|
		regs->pr = regs->pc + 4;
 | 
						|
 | 
						|
	if (nib[0] == 0xa || nib[0] == 0xb) { /* bra & bsr */
 | 
						|
		nextpc = regs->pc + 4 + ((short) ((insn & 0xfff) << 4) >> 3);
 | 
						|
		finsn = *(unsigned short *) (regs->pc + 2);
 | 
						|
	} else if (nib[0] == 0x8 && nib[1] == 0xd) { /* bt/s */
 | 
						|
		if (regs->sr & 1)
 | 
						|
			nextpc = regs->pc + 4 + ((char) (insn & 0xff) << 1);
 | 
						|
		else
 | 
						|
			nextpc = regs->pc + 4;
 | 
						|
		finsn = *(unsigned short *) (regs->pc + 2);
 | 
						|
	} else if (nib[0] == 0x8 && nib[1] == 0xf) { /* bf/s */
 | 
						|
		if (regs->sr & 1)
 | 
						|
			nextpc = regs->pc + 4;
 | 
						|
		else
 | 
						|
			nextpc = regs->pc + 4 + ((char) (insn & 0xff) << 1);
 | 
						|
		finsn = *(unsigned short *) (regs->pc + 2);
 | 
						|
	} else if (nib[0] == 0x4 && nib[3] == 0xb &&
 | 
						|
		 (nib[2] == 0x0 || nib[2] == 0x2)) { /* jmp & jsr */
 | 
						|
		nextpc = regs->regs[nib[1]];
 | 
						|
		finsn = *(unsigned short *) (regs->pc + 2);
 | 
						|
	} else if (nib[0] == 0x0 && nib[3] == 0x3 &&
 | 
						|
		 (nib[2] == 0x0 || nib[2] == 0x2)) { /* braf & bsrf */
 | 
						|
		nextpc = regs->pc + 4 + regs->regs[nib[1]];
 | 
						|
		finsn = *(unsigned short *) (regs->pc + 2);
 | 
						|
	} else if (insn == 0x000b) { /* rts */
 | 
						|
		nextpc = regs->pr;
 | 
						|
		finsn = *(unsigned short *) (regs->pc + 2);
 | 
						|
	} else {
 | 
						|
		nextpc = regs->pc + 2;
 | 
						|
		finsn = insn;
 | 
						|
	}
 | 
						|
 | 
						|
	if ((finsn & 0xf1ff) == 0xf0ad) { /* fcnvsd */
 | 
						|
		struct task_struct *tsk = current;
 | 
						|
 | 
						|
		if ((tsk->thread.xstate->softfpu.fpscr & (1 << 17))) {
 | 
						|
			/* FPU error */
 | 
						|
			denormal_to_double (&tsk->thread.xstate->softfpu,
 | 
						|
					    (finsn >> 8) & 0xf);
 | 
						|
			tsk->thread.xstate->softfpu.fpscr &=
 | 
						|
				~(FPSCR_CAUSE_MASK | FPSCR_FLAG_MASK);
 | 
						|
			task_thread_info(tsk)->status |= TS_USEDFPU;
 | 
						|
		} else {
 | 
						|
			force_sig_fault(SIGFPE, FPE_FLTINV,
 | 
						|
					(void __user *)regs->pc);
 | 
						|
		}
 | 
						|
 | 
						|
		regs->pc = nextpc;
 | 
						|
		return 1;
 | 
						|
	}
 | 
						|
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * fpu_init - Initialize FPU registers
 | 
						|
 * @fpu: Pointer to software emulated FPU registers.
 | 
						|
 */
 | 
						|
static void fpu_init(struct sh_fpu_soft_struct *fpu)
 | 
						|
{
 | 
						|
	int i;
 | 
						|
 | 
						|
	fpu->fpscr = FPSCR_INIT;
 | 
						|
	fpu->fpul = 0;
 | 
						|
 | 
						|
	for (i = 0; i < 16; i++) {
 | 
						|
		fpu->fp_regs[i] = 0;
 | 
						|
		fpu->xfp_regs[i]= 0;
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * do_fpu_inst - Handle reserved instructions for FPU emulation
 | 
						|
 * @inst: instruction code.
 | 
						|
 * @regs: registers on stack.
 | 
						|
 */
 | 
						|
int do_fpu_inst(unsigned short inst, struct pt_regs *regs)
 | 
						|
{
 | 
						|
	struct task_struct *tsk = current;
 | 
						|
	struct sh_fpu_soft_struct *fpu = &(tsk->thread.xstate->softfpu);
 | 
						|
 | 
						|
	perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0);
 | 
						|
 | 
						|
	if (!(task_thread_info(tsk)->status & TS_USEDFPU)) {
 | 
						|
		/* initialize once. */
 | 
						|
		fpu_init(fpu);
 | 
						|
		task_thread_info(tsk)->status |= TS_USEDFPU;
 | 
						|
	}
 | 
						|
 | 
						|
	return fpu_emulate(inst, fpu, regs);
 | 
						|
}
 |