CTC++ Coverage Report

Start/	End/
True	False	-	Line	Source

			1	/*
			2	* Copyright 2002 Andi Kleen, SuSE Labs.
			3	* FXSAVE<->i387 conversion support. Based on code by Gareth Hughes.
			4	* This is used for ptrace, signals and coredumps in 32bit emulation.
			5	* $Id: fpu32.c,v 1.1 2002/03/21 14:16:32 ak Exp $
			6	*/
			7
			8	#include <linux/sched.h>
			9	#include <asm/sigcontext32.h>
			10	#include <asm/processor.h>
			11	#include <asm/uaccess.h>
			12	#include <asm/i387.h>
			13

112	0		14	static inline unsigned short twd_i387_to_fxsr(unsigned short twd)
			15	{
			16	unsigned int tmp; /* to avoid 16 bit prefixes in the code */
			17
			18	/* Transform each pair of bits into 01 (valid) or 00 (empty) */
			19	tmp = ~twd;
			20	tmp = (tmp \| (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
			21	/* and move the valid bits to the lower byte. */
			22	tmp = (tmp \| (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
			23	tmp = (tmp \| (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
			24	tmp = (tmp \| (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
112			25	return tmp;
			26	}
			27

114	0		28	static inline unsigned long twd_fxsr_to_i387(struct i387_fxsave_struct *fxsave)
			29	{
			30	struct _fpxreg *st = NULL;
			31	unsigned long tos = (fxsave->swd >> 11) & 7;
			32	unsigned long twd = (unsigned long) fxsave->twd;
			33	unsigned long tag;
			34	unsigned long ret = 0xffff0000;
			35	int i;
			36
			37	#define FPREG_ADDR(f, n) ((void )&(f)->st_space + (n) 16);
			38
912	114		39	for (i = 0 ; i < 8 ; i++) {
0	912	-	40	if (twd & 0x1) {
			41	st = FPREG_ADDR( fxsave, (i - tos) & 7 );
			42
			43	switch (st->exponent & 0x7fff) {
0		-	44	case 0x7fff:
			45	tag = 2; /* Special */
0		-	46	break;
0		-	47	case 0x0000:
			48	if ( !st->significand[0] &&
			49	!st->significand[1] &&
			50	!st->significand[2] &&
0	0	-	51	!st->significand[3] ) {
0		-	51	T && T && T && T
	0	-	51	T && T && T && F
	0	-	51	T && T && F && _
	0	-	51	T && F && _ && _
	0	-	51	F && _ && _ && _
			52	tag = 1; /* Zero */
			53	} else {
			54	tag = 2; /* Special */
			55	}
0		-	56	break;
0		-	57	default:
0	0	-	58	if (st->significand[3] & 0x8000) {
			59	tag = 0; /* Valid */
			60	} else {
			61	tag = 2; /* Special */
			62	}
0		-	63	break;
			64	}
			65	} else {
			66	tag = 3; /* Empty */
			67	}
			68	ret \|= (tag << (2 * i));
			69	twd = twd >> 1;
			70	}
114			71	return ret;
			72	}
			73
			74

112	0		75	static inline int convert_fxsr_from_user(struct i387_fxsave_struct *fxsave,
			76	struct _fpstate_ia32 __user *buf)
			77	{
			78	struct _fpxreg *to;
			79	struct _fpreg __user *from;
			80	int i;
			81	u32 v;
			82	int err = 0;
			83
			84	#define G(num,val) err \|= __get_user(val, num + (u32 __user *)buf)
			85	G(0, fxsave->cwd);
			86	G(1, fxsave->swd);
			87	G(2, fxsave->twd);
			88	fxsave->twd = twd_i387_to_fxsr(fxsave->twd);
			89	G(3, fxsave->rip);
			90	G(4, v);
			91	fxsave->fop = v>>16; /* cs ignored */
			92	G(5, fxsave->rdp);
			93	/* 6: ds ignored */
			94	#undef G
0	112	-	95	if (err)
0		-	96	return -1;
			97
			98	to = (struct _fpxreg *)&fxsave->st_space[0];
			99	from = &buf->_st[0];
896	112		100	for (i = 0 ; i < 8 ; i++, to++, from++) {
0	896	-	101	if (__copy_from_user(to, from, sizeof(*from)))
0		-	102	return -1;
			103	}
112			104	return 0;
			105	}
			106
			107

114	0		108	static inline int convert_fxsr_to_user(struct _fpstate_ia32 __user *buf,
			109	struct i387_fxsave_struct *fxsave,
			110	struct pt_regs *regs,
			111	struct task_struct *tsk)
			112	{
			113	struct _fpreg __user *to;
			114	struct _fpxreg *from;
			115	int i;
			116	u16 cs,ds;
			117	int err = 0;
			118
114	0	-	119	if (tsk == current) {
			120	/* should be actually ds/cs at fpu exception time,
			121	but that information is not available in 64bit mode. */
			122	asm("movw %%ds,%0 " : "=r" (ds));
			123	asm("movw %%cs,%0 " : "=r" (cs));
			124	} else { /* ptrace. task has stopped. */
			125	ds = tsk->thread.ds;
			126	cs = regs->cs;
			127	}
			128
			129	#define P(num,val) err \|= __put_user(val, num + (u32 __user *)buf)
			130	P(0, (u32)fxsave->cwd \| 0xffff0000);
			131	P(1, (u32)fxsave->swd \| 0xffff0000);
			132	P(2, twd_fxsr_to_i387(fxsave));
			133	P(3, (u32)fxsave->rip);
			134	P(4, cs \| ((u32)fxsave->fop) << 16);
			135	P(5, fxsave->rdp);
			136	P(6, 0xffff0000 \| ds);
			137	#undef P
			138
0	114	-	139	if (err)
0		-	140	return -1;
			141
			142	to = &buf->_st[0];
			143	from = (struct _fpxreg *) &fxsave->st_space[0];
912	114		144	for ( i = 0 ; i < 8 ; i++, to++, from++ ) {
0	912	-	145	if (__copy_to_user(to, from, sizeof(*to)))
0		-	146	return -1;
			147	}
114			148	return 0;
			149	}
			150

112	0		151	int restore_i387_ia32(struct task_struct tsk, struct _fpstate_ia32 __user buf, int fsave)
			152	{
			153	clear_fpu(tsk);
0	112	-	153	if (( tsk ) -> thread_info -> status & 0x0001)
0	112	-	153	do-while (0)
112	0	-	154	if (!fsave) {
			155	if (__copy_from_user(&tsk->thread.i387.fxsave,
			156	&buf->_fxsr_env[0],
0	112	-	157	sizeof(struct i387_fxsave_struct)))
0		-	158	return -1;
			159	tsk->thread.i387.fxsave.mxcsr &= mxcsr_feature_mask;
			160	set_stopped_child_used_math(tsk);
0	112	-	160	do-while (0)
			161	}
112			162	return convert_fxsr_from_user(&tsk->thread.i387.fxsave, buf);
			163	}
			164

114	0		165	int save_i387_ia32(struct task_struct *tsk,
			166	struct _fpstate_ia32 __user *buf,
			167	struct pt_regs *regs,
			168	int fsave)
			169	{
			170	int err = 0;
			171
			172	init_fpu(tsk);
0	114	-	173	if (convert_fxsr_to_user(buf, &tsk->thread.i387.fxsave, regs, tsk))
0		-	174	return -1;
0	114	-	175	if (fsave)
0		-	176	return 0;
			177	err \|= __put_user(tsk->thread.i387.fxsave.swd, &buf->status);
0	114	-	178	if (fsave)
			179	return err ? -1 : 1;
0	0	-	179	ternary-?: err
0		-	179	return err ? - 1 : 1
			180	err \|= __put_user(X86_FXSR_MAGIC, &buf->magic);
			181	err \|= __copy_to_user(&buf->_fxsr_env[0], &tsk->thread.i387.fxsave,
			182	sizeof(struct i387_fxsave_struct));
			183	return err ? -1 : 1;
0	114	-	183	ternary-?: err
114			183	return err ? - 1 : 1
			184	}
***TER 45% (33/73) of SOURCE FILE fpu32.c