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[/] [or1k_old/] [trunk/] [rc203soc/] [sw/] [uClinux/] [arch/] [i386/] [math-emu/] [fpu_etc.c] - Blame information for rev 1782

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/*---------------------------------------------------------------------------+
 |  fpu_etc.c                                                                |
 |                                                                           |
 | Implement a few FPU instructions.                                         |
 |                                                                           |
 | Copyright (C) 1992,1993,1994                                              |
 |                       W. Metzenthen, 22 Parker St, Ormond, Vic 3163,      |
 |                       Australia.  E-mail   billm@vaxc.cc.monash.edu.au    |
 |                                                                           |
 |                                                                           |
 +---------------------------------------------------------------------------*/
 
#include "fpu_system.h"
#include "exception.h"
#include "fpu_emu.h"
#include "status_w.h"
#include "reg_constant.h"
 
 
static void fchs(FPU_REG *st0_ptr)
{
  if ( st0_ptr->tag ^ TW_Empty )
    {
      st0_ptr->sign ^= SIGN_POS^SIGN_NEG;
      clear_C1();
    }
  else
    stack_underflow();
}
 
static void fabs(FPU_REG *st0_ptr)
{
  if ( st0_ptr->tag ^ TW_Empty )
    {
      st0_ptr->sign = SIGN_POS;
      clear_C1();
    }
  else
    stack_underflow();
}
 
 
static void ftst_(FPU_REG *st0_ptr)
{
  switch (st0_ptr->tag)
    {
    case TW_Zero:
      setcc(SW_C3);
      break;
    case TW_Valid:
      if (st0_ptr->sign == SIGN_POS)
        setcc(0);
      else
        setcc(SW_C0);
 
#ifdef DENORM_OPERAND
      if ( (st0_ptr->exp <= EXP_UNDER) && (denormal_operand()) )
        {
#ifdef PECULIAR_486
          /* This is weird! */
          if (st0_ptr->sign == SIGN_POS)
            setcc(SW_C3);
#endif PECULIAR_486
          return;
        }
#endif DENORM_OPERAND
 
      break;
    case TW_NaN:
      setcc(SW_C0|SW_C2|SW_C3);   /* Operand is not comparable */
      EXCEPTION(EX_Invalid);
      break;
    case TW_Infinity:
      if (st0_ptr->sign == SIGN_POS)
        setcc(0);
      else
        setcc(SW_C0);
      break;
    case TW_Empty:
      setcc(SW_C0|SW_C2|SW_C3);
      EXCEPTION(EX_StackUnder);
      break;
    default:
      setcc(SW_C0|SW_C2|SW_C3);   /* Operand is not comparable */
      EXCEPTION(EX_INTERNAL|0x14);
      break;
    }
}
 
static void fxam(FPU_REG *st0_ptr)
{
  int c=0;
  switch (st0_ptr->tag)
    {
    case TW_Empty:
      c = SW_C3|SW_C0;
      break;
    case TW_Zero:
      c = SW_C3;
      break;
    case TW_Valid:
      /* This will need to be changed if TW_Denormal is ever used. */
      if ( st0_ptr->exp <= EXP_UNDER )
        c = SW_C2|SW_C3;  /* Denormal */
      else
        c = SW_C2;
      break;
    case TW_NaN:
      c = SW_C0;
      break;
    case TW_Infinity:
      c = SW_C2|SW_C0;
      break;
    }
  if (st0_ptr->sign == SIGN_NEG)
    c |= SW_C1;
  setcc(c);
}
 
 
static FUNC_ST0 const fp_etc_table[] = {
  fchs, fabs, (FUNC_ST0)FPU_illegal, (FUNC_ST0)FPU_illegal,
  ftst_, fxam, (FUNC_ST0)FPU_illegal, (FUNC_ST0)FPU_illegal
};
 
void fp_etc()
{
  (fp_etc_table[FPU_rm])(&st(0));
}

Line No.	Rev	Author	Line
1	1623	jcastillo	`/*---------------------------------------------------------------------------+`
2			`\| fpu_etc.c \|`
3			`\| \|`
4			`\| Implement a few FPU instructions. \|`
5			`\| \|`
6			`\| Copyright (C) 1992,1993,1994 \|`
7			`\| W. Metzenthen, 22 Parker St, Ormond, Vic 3163, \|`
8			`\| Australia. E-mail billm@vaxc.cc.monash.edu.au \|`
9			`\| \|`
10			`\| \|`
11			`+---------------------------------------------------------------------------*/`
12
13			`#include "fpu_system.h"`
14			`#include "exception.h"`
15			`#include "fpu_emu.h"`
16			`#include "status_w.h"`
17			`#include "reg_constant.h"`
18
19
20			`static void fchs(FPU_REG *st0_ptr)`
21			`{`
22			`if ( st0_ptr->tag ^ TW_Empty )`
23			`{`
24			`st0_ptr->sign ^= SIGN_POS^SIGN_NEG;`
25			`clear_C1();`
26			`}`
27			`else`
28			`stack_underflow();`
29			`}`
30
31			`static void fabs(FPU_REG *st0_ptr)`
32			`{`
33			`if ( st0_ptr->tag ^ TW_Empty )`
34			`{`
35			`st0_ptr->sign = SIGN_POS;`
36			`clear_C1();`
37			`}`
38			`else`
39			`stack_underflow();`
40			`}`
41
42
43			`static void ftst_(FPU_REG *st0_ptr)`
44			`{`
45			`switch (st0_ptr->tag)`
46			`{`
47			`case TW_Zero:`
48			`setcc(SW_C3);`
49			`break;`
50			`case TW_Valid:`
51			`if (st0_ptr->sign == SIGN_POS)`
52			`setcc(0);`
53			`else`
54			`setcc(SW_C0);`
55
56			`#ifdef DENORM_OPERAND`
57			`if ( (st0_ptr->exp <= EXP_UNDER) && (denormal_operand()) )`
58			`{`
59			`#ifdef PECULIAR_486`
60			`/* This is weird! */`
61			`if (st0_ptr->sign == SIGN_POS)`
62			`setcc(SW_C3);`
63			`#endif PECULIAR_486`
64			`return;`
65			`}`
66			`#endif DENORM_OPERAND`
67
68			`break;`
69			`case TW_NaN:`
70			`setcc(SW_C0\|SW_C2\|SW_C3); /* Operand is not comparable */`
71			`EXCEPTION(EX_Invalid);`
72			`break;`
73			`case TW_Infinity:`
74			`if (st0_ptr->sign == SIGN_POS)`
75			`setcc(0);`
76			`else`
77			`setcc(SW_C0);`
78			`break;`
79			`case TW_Empty:`
80			`setcc(SW_C0\|SW_C2\|SW_C3);`
81			`EXCEPTION(EX_StackUnder);`
82			`break;`
83			`default:`
84			`setcc(SW_C0\|SW_C2\|SW_C3); /* Operand is not comparable */`
85			`EXCEPTION(EX_INTERNAL\|0x14);`
86			`break;`
87			`}`
88			`}`
89
90			`static void fxam(FPU_REG *st0_ptr)`
91			`{`
92			`int c=0;`
93			`switch (st0_ptr->tag)`
94			`{`
95			`case TW_Empty:`
96			`c = SW_C3\|SW_C0;`
97			`break;`
98			`case TW_Zero:`
99			`c = SW_C3;`
100			`break;`
101			`case TW_Valid:`
102			`/* This will need to be changed if TW_Denormal is ever used. */`
103			`if ( st0_ptr->exp <= EXP_UNDER )`
104			`c = SW_C2\|SW_C3; /* Denormal */`
105			`else`
106			`c = SW_C2;`
107			`break;`
108			`case TW_NaN:`
109			`c = SW_C0;`
110			`break;`
111			`case TW_Infinity:`
112			`c = SW_C2\|SW_C0;`
113			`break;`
114			`}`
115			`if (st0_ptr->sign == SIGN_NEG)`
116			`c \|= SW_C1;`
117			`setcc(c);`
118			`}`
119
120
121			`static FUNC_ST0 const fp_etc_table[] = {`
122			`fchs, fabs, (FUNC_ST0)FPU_illegal, (FUNC_ST0)FPU_illegal,`
123			`ftst_, fxam, (FUNC_ST0)FPU_illegal, (FUNC_ST0)FPU_illegal`
124			`};`
125
126			`void fp_etc()`
127			`{`
128			`(fp_etc_table[FPU_rm])(&st(0));`
129			`}`

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[/] [or1k_old/] [trunk/] [rc203soc/] [sw/] [uClinux/] [arch/] [i386/] [math-emu/] [fpu_etc.c] - Blame information for rev 1782