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-rw-r--r--arch/x86/math-emu/errors.c888
1 files changed, 419 insertions, 469 deletions
diff --git a/arch/x86/math-emu/errors.c b/arch/x86/math-emu/errors.c
index a1b0d22f6978..7cb5bf3495b2 100644
--- a/arch/x86/math-emu/errors.c
+++ b/arch/x86/math-emu/errors.c
@@ -33,45 +33,41 @@
33#undef PRINT_MESSAGES 33#undef PRINT_MESSAGES
34/* */ 34/* */
35 35
36
37#if 0 36#if 0
38void Un_impl(void) 37void Un_impl(void)
39{ 38{
40 u_char byte1, FPU_modrm; 39 u_char byte1, FPU_modrm;
41 unsigned long address = FPU_ORIG_EIP; 40 unsigned long address = FPU_ORIG_EIP;
42 41
43 RE_ENTRANT_CHECK_OFF; 42 RE_ENTRANT_CHECK_OFF;
44 /* No need to check access_ok(), we have previously fetched these bytes. */ 43 /* No need to check access_ok(), we have previously fetched these bytes. */
45 printk("Unimplemented FPU Opcode at eip=%p : ", (void __user *) address); 44 printk("Unimplemented FPU Opcode at eip=%p : ", (void __user *)address);
46 if ( FPU_CS == __USER_CS ) 45 if (FPU_CS == __USER_CS) {
47 { 46 while (1) {
48 while ( 1 ) 47 FPU_get_user(byte1, (u_char __user *) address);
49 { 48 if ((byte1 & 0xf8) == 0xd8)
50 FPU_get_user(byte1, (u_char __user *) address); 49 break;
51 if ( (byte1 & 0xf8) == 0xd8 ) break; 50 printk("[%02x]", byte1);
52 printk("[%02x]", byte1); 51 address++;
53 address++; 52 }
53 printk("%02x ", byte1);
54 FPU_get_user(FPU_modrm, 1 + (u_char __user *) address);
55
56 if (FPU_modrm >= 0300)
57 printk("%02x (%02x+%d)\n", FPU_modrm, FPU_modrm & 0xf8,
58 FPU_modrm & 7);
59 else
60 printk("/%d\n", (FPU_modrm >> 3) & 7);
61 } else {
62 printk("cs selector = %04x\n", FPU_CS);
54 } 63 }
55 printk("%02x ", byte1);
56 FPU_get_user(FPU_modrm, 1 + (u_char __user *) address);
57
58 if (FPU_modrm >= 0300)
59 printk("%02x (%02x+%d)\n", FPU_modrm, FPU_modrm & 0xf8, FPU_modrm & 7);
60 else
61 printk("/%d\n", (FPU_modrm >> 3) & 7);
62 }
63 else
64 {
65 printk("cs selector = %04x\n", FPU_CS);
66 }
67
68 RE_ENTRANT_CHECK_ON;
69
70 EXCEPTION(EX_Invalid);
71 64
72} 65 RE_ENTRANT_CHECK_ON;
73#endif /* 0 */
74 66
67 EXCEPTION(EX_Invalid);
68
69}
70#endif /* 0 */
75 71
76/* 72/*
77 Called for opcodes which are illegal and which are known to result in a 73 Called for opcodes which are illegal and which are known to result in a
@@ -79,139 +75,152 @@ void Un_impl(void)
79 */ 75 */
80void FPU_illegal(void) 76void FPU_illegal(void)
81{ 77{
82 math_abort(FPU_info,SIGILL); 78 math_abort(FPU_info, SIGILL);
83} 79}
84 80
85
86
87void FPU_printall(void) 81void FPU_printall(void)
88{ 82{
89 int i; 83 int i;
90 static const char *tag_desc[] = { "Valid", "Zero", "ERROR", "Empty", 84 static const char *tag_desc[] = { "Valid", "Zero", "ERROR", "Empty",
91 "DeNorm", "Inf", "NaN" }; 85 "DeNorm", "Inf", "NaN"
92 u_char byte1, FPU_modrm; 86 };
93 unsigned long address = FPU_ORIG_EIP; 87 u_char byte1, FPU_modrm;
94 88 unsigned long address = FPU_ORIG_EIP;
95 RE_ENTRANT_CHECK_OFF; 89
96 /* No need to check access_ok(), we have previously fetched these bytes. */ 90 RE_ENTRANT_CHECK_OFF;
97 printk("At %p:", (void *) address); 91 /* No need to check access_ok(), we have previously fetched these bytes. */
98 if ( FPU_CS == __USER_CS ) 92 printk("At %p:", (void *)address);
99 { 93 if (FPU_CS == __USER_CS) {
100#define MAX_PRINTED_BYTES 20 94#define MAX_PRINTED_BYTES 20
101 for ( i = 0; i < MAX_PRINTED_BYTES; i++ ) 95 for (i = 0; i < MAX_PRINTED_BYTES; i++) {
102 { 96 FPU_get_user(byte1, (u_char __user *) address);
103 FPU_get_user(byte1, (u_char __user *) address); 97 if ((byte1 & 0xf8) == 0xd8) {
104 if ( (byte1 & 0xf8) == 0xd8 ) 98 printk(" %02x", byte1);
105 { 99 break;
106 printk(" %02x", byte1); 100 }
107 break; 101 printk(" [%02x]", byte1);
108 } 102 address++;
109 printk(" [%02x]", byte1); 103 }
110 address++; 104 if (i == MAX_PRINTED_BYTES)
111 } 105 printk(" [more..]\n");
112 if ( i == MAX_PRINTED_BYTES ) 106 else {
113 printk(" [more..]\n"); 107 FPU_get_user(FPU_modrm, 1 + (u_char __user *) address);
114 else 108
115 { 109 if (FPU_modrm >= 0300)
116 FPU_get_user(FPU_modrm, 1 + (u_char __user *) address); 110 printk(" %02x (%02x+%d)\n", FPU_modrm,
117 111 FPU_modrm & 0xf8, FPU_modrm & 7);
118 if (FPU_modrm >= 0300) 112 else
119 printk(" %02x (%02x+%d)\n", FPU_modrm, FPU_modrm & 0xf8, FPU_modrm & 7); 113 printk(" /%d, mod=%d rm=%d\n",
120 else 114 (FPU_modrm >> 3) & 7,
121 printk(" /%d, mod=%d rm=%d\n", 115 (FPU_modrm >> 6) & 3, FPU_modrm & 7);
122 (FPU_modrm >> 3) & 7, (FPU_modrm >> 6) & 3, FPU_modrm & 7); 116 }
117 } else {
118 printk("%04x\n", FPU_CS);
123 } 119 }
124 }
125 else
126 {
127 printk("%04x\n", FPU_CS);
128 }
129 120
130 partial_status = status_word(); 121 partial_status = status_word();
131 122
132#ifdef DEBUGGING 123#ifdef DEBUGGING
133if ( partial_status & SW_Backward ) printk("SW: backward compatibility\n"); 124 if (partial_status & SW_Backward)
134if ( partial_status & SW_C3 ) printk("SW: condition bit 3\n"); 125 printk("SW: backward compatibility\n");
135if ( partial_status & SW_C2 ) printk("SW: condition bit 2\n"); 126 if (partial_status & SW_C3)
136if ( partial_status & SW_C1 ) printk("SW: condition bit 1\n"); 127 printk("SW: condition bit 3\n");
137if ( partial_status & SW_C0 ) printk("SW: condition bit 0\n"); 128 if (partial_status & SW_C2)
138if ( partial_status & SW_Summary ) printk("SW: exception summary\n"); 129 printk("SW: condition bit 2\n");
139if ( partial_status & SW_Stack_Fault ) printk("SW: stack fault\n"); 130 if (partial_status & SW_C1)
140if ( partial_status & SW_Precision ) printk("SW: loss of precision\n"); 131 printk("SW: condition bit 1\n");
141if ( partial_status & SW_Underflow ) printk("SW: underflow\n"); 132 if (partial_status & SW_C0)
142if ( partial_status & SW_Overflow ) printk("SW: overflow\n"); 133 printk("SW: condition bit 0\n");
143if ( partial_status & SW_Zero_Div ) printk("SW: divide by zero\n"); 134 if (partial_status & SW_Summary)
144if ( partial_status & SW_Denorm_Op ) printk("SW: denormalized operand\n"); 135 printk("SW: exception summary\n");
145if ( partial_status & SW_Invalid ) printk("SW: invalid operation\n"); 136 if (partial_status & SW_Stack_Fault)
137 printk("SW: stack fault\n");
138 if (partial_status & SW_Precision)
139 printk("SW: loss of precision\n");
140 if (partial_status & SW_Underflow)
141 printk("SW: underflow\n");
142 if (partial_status & SW_Overflow)
143 printk("SW: overflow\n");
144 if (partial_status & SW_Zero_Div)
145 printk("SW: divide by zero\n");
146 if (partial_status & SW_Denorm_Op)
147 printk("SW: denormalized operand\n");
148 if (partial_status & SW_Invalid)
149 printk("SW: invalid operation\n");
146#endif /* DEBUGGING */ 150#endif /* DEBUGGING */
147 151
148 printk(" SW: b=%d st=%ld es=%d sf=%d cc=%d%d%d%d ef=%d%d%d%d%d%d\n", 152 printk(" SW: b=%d st=%ld es=%d sf=%d cc=%d%d%d%d ef=%d%d%d%d%d%d\n", partial_status & 0x8000 ? 1 : 0, /* busy */
149 partial_status & 0x8000 ? 1 : 0, /* busy */ 153 (partial_status & 0x3800) >> 11, /* stack top pointer */
150 (partial_status & 0x3800) >> 11, /* stack top pointer */ 154 partial_status & 0x80 ? 1 : 0, /* Error summary status */
151 partial_status & 0x80 ? 1 : 0, /* Error summary status */ 155 partial_status & 0x40 ? 1 : 0, /* Stack flag */
152 partial_status & 0x40 ? 1 : 0, /* Stack flag */ 156 partial_status & SW_C3 ? 1 : 0, partial_status & SW_C2 ? 1 : 0, /* cc */
153 partial_status & SW_C3?1:0, partial_status & SW_C2?1:0, /* cc */ 157 partial_status & SW_C1 ? 1 : 0, partial_status & SW_C0 ? 1 : 0, /* cc */
154 partial_status & SW_C1?1:0, partial_status & SW_C0?1:0, /* cc */ 158 partial_status & SW_Precision ? 1 : 0,
155 partial_status & SW_Precision?1:0, partial_status & SW_Underflow?1:0, 159 partial_status & SW_Underflow ? 1 : 0,
156 partial_status & SW_Overflow?1:0, partial_status & SW_Zero_Div?1:0, 160 partial_status & SW_Overflow ? 1 : 0,
157 partial_status & SW_Denorm_Op?1:0, partial_status & SW_Invalid?1:0); 161 partial_status & SW_Zero_Div ? 1 : 0,
158 162 partial_status & SW_Denorm_Op ? 1 : 0,
159printk(" CW: ic=%d rc=%ld%ld pc=%ld%ld iem=%d ef=%d%d%d%d%d%d\n", 163 partial_status & SW_Invalid ? 1 : 0);
160 control_word & 0x1000 ? 1 : 0, 164
161 (control_word & 0x800) >> 11, (control_word & 0x400) >> 10, 165 printk(" CW: ic=%d rc=%ld%ld pc=%ld%ld iem=%d ef=%d%d%d%d%d%d\n",
162 (control_word & 0x200) >> 9, (control_word & 0x100) >> 8, 166 control_word & 0x1000 ? 1 : 0,
163 control_word & 0x80 ? 1 : 0, 167 (control_word & 0x800) >> 11, (control_word & 0x400) >> 10,
164 control_word & SW_Precision?1:0, control_word & SW_Underflow?1:0, 168 (control_word & 0x200) >> 9, (control_word & 0x100) >> 8,
165 control_word & SW_Overflow?1:0, control_word & SW_Zero_Div?1:0, 169 control_word & 0x80 ? 1 : 0,
166 control_word & SW_Denorm_Op?1:0, control_word & SW_Invalid?1:0); 170 control_word & SW_Precision ? 1 : 0,
167 171 control_word & SW_Underflow ? 1 : 0,
168 for ( i = 0; i < 8; i++ ) 172 control_word & SW_Overflow ? 1 : 0,
169 { 173 control_word & SW_Zero_Div ? 1 : 0,
170 FPU_REG *r = &st(i); 174 control_word & SW_Denorm_Op ? 1 : 0,
171 u_char tagi = FPU_gettagi(i); 175 control_word & SW_Invalid ? 1 : 0);
172 switch (tagi) 176
173 { 177 for (i = 0; i < 8; i++) {
174 case TAG_Empty: 178 FPU_REG *r = &st(i);
175 continue; 179 u_char tagi = FPU_gettagi(i);
176 break; 180 switch (tagi) {
177 case TAG_Zero: 181 case TAG_Empty:
178 case TAG_Special: 182 continue;
179 tagi = FPU_Special(r); 183 break;
180 case TAG_Valid: 184 case TAG_Zero:
181 printk("st(%d) %c .%04lx %04lx %04lx %04lx e%+-6d ", i, 185 case TAG_Special:
182 getsign(r) ? '-' : '+', 186 tagi = FPU_Special(r);
183 (long)(r->sigh >> 16), 187 case TAG_Valid:
184 (long)(r->sigh & 0xFFFF), 188 printk("st(%d) %c .%04lx %04lx %04lx %04lx e%+-6d ", i,
185 (long)(r->sigl >> 16), 189 getsign(r) ? '-' : '+',
186 (long)(r->sigl & 0xFFFF), 190 (long)(r->sigh >> 16),
187 exponent(r) - EXP_BIAS + 1); 191 (long)(r->sigh & 0xFFFF),
188 break; 192 (long)(r->sigl >> 16),
189 default: 193 (long)(r->sigl & 0xFFFF),
190 printk("Whoops! Error in errors.c: tag%d is %d ", i, tagi); 194 exponent(r) - EXP_BIAS + 1);
191 continue; 195 break;
192 break; 196 default:
197 printk("Whoops! Error in errors.c: tag%d is %d ", i,
198 tagi);
199 continue;
200 break;
201 }
202 printk("%s\n", tag_desc[(int)(unsigned)tagi]);
193 } 203 }
194 printk("%s\n", tag_desc[(int) (unsigned) tagi]);
195 }
196 204
197 RE_ENTRANT_CHECK_ON; 205 RE_ENTRANT_CHECK_ON;
198 206
199} 207}
200 208
201static struct { 209static struct {
202 int type; 210 int type;
203 const char *name; 211 const char *name;
204} exception_names[] = { 212} exception_names[] = {
205 { EX_StackOver, "stack overflow" }, 213 {
206 { EX_StackUnder, "stack underflow" }, 214 EX_StackOver, "stack overflow"}, {
207 { EX_Precision, "loss of precision" }, 215 EX_StackUnder, "stack underflow"}, {
208 { EX_Underflow, "underflow" }, 216 EX_Precision, "loss of precision"}, {
209 { EX_Overflow, "overflow" }, 217 EX_Underflow, "underflow"}, {
210 { EX_ZeroDiv, "divide by zero" }, 218 EX_Overflow, "overflow"}, {
211 { EX_Denormal, "denormalized operand" }, 219 EX_ZeroDiv, "divide by zero"}, {
212 { EX_Invalid, "invalid operation" }, 220 EX_Denormal, "denormalized operand"}, {
213 { EX_INTERNAL, "INTERNAL BUG in "FPU_VERSION }, 221 EX_Invalid, "invalid operation"}, {
214 { 0, NULL } 222 EX_INTERNAL, "INTERNAL BUG in " FPU_VERSION}, {
223 0, NULL}
215}; 224};
216 225
217/* 226/*
@@ -295,445 +304,386 @@ static struct {
295 304
296asmlinkage void FPU_exception(int n) 305asmlinkage void FPU_exception(int n)
297{ 306{
298 int i, int_type; 307 int i, int_type;
299 308
300 int_type = 0; /* Needed only to stop compiler warnings */ 309 int_type = 0; /* Needed only to stop compiler warnings */
301 if ( n & EX_INTERNAL ) 310 if (n & EX_INTERNAL) {
302 { 311 int_type = n - EX_INTERNAL;
303 int_type = n - EX_INTERNAL; 312 n = EX_INTERNAL;
304 n = EX_INTERNAL; 313 /* Set lots of exception bits! */
305 /* Set lots of exception bits! */ 314 partial_status |= (SW_Exc_Mask | SW_Summary | SW_Backward);
306 partial_status |= (SW_Exc_Mask | SW_Summary | SW_Backward); 315 } else {
307 } 316 /* Extract only the bits which we use to set the status word */
308 else 317 n &= (SW_Exc_Mask);
309 { 318 /* Set the corresponding exception bit */
310 /* Extract only the bits which we use to set the status word */ 319 partial_status |= n;
311 n &= (SW_Exc_Mask); 320 /* Set summary bits iff exception isn't masked */
312 /* Set the corresponding exception bit */ 321 if (partial_status & ~control_word & CW_Exceptions)
313 partial_status |= n; 322 partial_status |= (SW_Summary | SW_Backward);
314 /* Set summary bits iff exception isn't masked */ 323 if (n & (SW_Stack_Fault | EX_Precision)) {
315 if ( partial_status & ~control_word & CW_Exceptions ) 324 if (!(n & SW_C1))
316 partial_status |= (SW_Summary | SW_Backward); 325 /* This bit distinguishes over- from underflow for a stack fault,
317 if ( n & (SW_Stack_Fault | EX_Precision) ) 326 and roundup from round-down for precision loss. */
318 { 327 partial_status &= ~SW_C1;
319 if ( !(n & SW_C1) ) 328 }
320 /* This bit distinguishes over- from underflow for a stack fault,
321 and roundup from round-down for precision loss. */
322 partial_status &= ~SW_C1;
323 } 329 }
324 }
325 330
326 RE_ENTRANT_CHECK_OFF; 331 RE_ENTRANT_CHECK_OFF;
327 if ( (~control_word & n & CW_Exceptions) || (n == EX_INTERNAL) ) 332 if ((~control_word & n & CW_Exceptions) || (n == EX_INTERNAL)) {
328 {
329#ifdef PRINT_MESSAGES 333#ifdef PRINT_MESSAGES
330 /* My message from the sponsor */ 334 /* My message from the sponsor */
331 printk(FPU_VERSION" "__DATE__" (C) W. Metzenthen.\n"); 335 printk(FPU_VERSION " " __DATE__ " (C) W. Metzenthen.\n");
332#endif /* PRINT_MESSAGES */ 336#endif /* PRINT_MESSAGES */
333 337
334 /* Get a name string for error reporting */ 338 /* Get a name string for error reporting */
335 for (i=0; exception_names[i].type; i++) 339 for (i = 0; exception_names[i].type; i++)
336 if ( (exception_names[i].type & n) == exception_names[i].type ) 340 if ((exception_names[i].type & n) ==
337 break; 341 exception_names[i].type)
338 342 break;
339 if (exception_names[i].type) 343
340 { 344 if (exception_names[i].type) {
341#ifdef PRINT_MESSAGES 345#ifdef PRINT_MESSAGES
342 printk("FP Exception: %s!\n", exception_names[i].name); 346 printk("FP Exception: %s!\n", exception_names[i].name);
343#endif /* PRINT_MESSAGES */ 347#endif /* PRINT_MESSAGES */
344 } 348 } else
345 else 349 printk("FPU emulator: Unknown Exception: 0x%04x!\n", n);
346 printk("FPU emulator: Unknown Exception: 0x%04x!\n", n); 350
347 351 if (n == EX_INTERNAL) {
348 if ( n == EX_INTERNAL ) 352 printk("FPU emulator: Internal error type 0x%04x\n",
349 { 353 int_type);
350 printk("FPU emulator: Internal error type 0x%04x\n", int_type); 354 FPU_printall();
351 FPU_printall(); 355 }
352 }
353#ifdef PRINT_MESSAGES 356#ifdef PRINT_MESSAGES
354 else 357 else
355 FPU_printall(); 358 FPU_printall();
356#endif /* PRINT_MESSAGES */ 359#endif /* PRINT_MESSAGES */
357 360
358 /* 361 /*
359 * The 80486 generates an interrupt on the next non-control FPU 362 * The 80486 generates an interrupt on the next non-control FPU
360 * instruction. So we need some means of flagging it. 363 * instruction. So we need some means of flagging it.
361 * We use the ES (Error Summary) bit for this. 364 * We use the ES (Error Summary) bit for this.
362 */ 365 */
363 } 366 }
364 RE_ENTRANT_CHECK_ON; 367 RE_ENTRANT_CHECK_ON;
365 368
366#ifdef __DEBUG__ 369#ifdef __DEBUG__
367 math_abort(FPU_info,SIGFPE); 370 math_abort(FPU_info, SIGFPE);
368#endif /* __DEBUG__ */ 371#endif /* __DEBUG__ */
369 372
370} 373}
371 374
372
373/* Real operation attempted on a NaN. */ 375/* Real operation attempted on a NaN. */
374/* Returns < 0 if the exception is unmasked */ 376/* Returns < 0 if the exception is unmasked */
375int real_1op_NaN(FPU_REG *a) 377int real_1op_NaN(FPU_REG * a)
376{ 378{
377 int signalling, isNaN; 379 int signalling, isNaN;
378 380
379 isNaN = (exponent(a) == EXP_OVER) && (a->sigh & 0x80000000); 381 isNaN = (exponent(a) == EXP_OVER) && (a->sigh & 0x80000000);
380 382
381 /* The default result for the case of two "equal" NaNs (signs may 383 /* The default result for the case of two "equal" NaNs (signs may
382 differ) is chosen to reproduce 80486 behaviour */ 384 differ) is chosen to reproduce 80486 behaviour */
383 signalling = isNaN && !(a->sigh & 0x40000000); 385 signalling = isNaN && !(a->sigh & 0x40000000);
384 386
385 if ( !signalling ) 387 if (!signalling) {
386 { 388 if (!isNaN) { /* pseudo-NaN, or other unsupported? */
387 if ( !isNaN ) /* pseudo-NaN, or other unsupported? */ 389 if (control_word & CW_Invalid) {
388 { 390 /* Masked response */
389 if ( control_word & CW_Invalid ) 391 reg_copy(&CONST_QNaN, a);
390 { 392 }
391 /* Masked response */ 393 EXCEPTION(EX_Invalid);
392 reg_copy(&CONST_QNaN, a); 394 return (!(control_word & CW_Invalid) ? FPU_Exception :
393 } 395 0) | TAG_Special;
394 EXCEPTION(EX_Invalid); 396 }
395 return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Special; 397 return TAG_Special;
396 } 398 }
397 return TAG_Special;
398 }
399 399
400 if ( control_word & CW_Invalid ) 400 if (control_word & CW_Invalid) {
401 { 401 /* The masked response */
402 /* The masked response */ 402 if (!(a->sigh & 0x80000000)) { /* pseudo-NaN ? */
403 if ( !(a->sigh & 0x80000000) ) /* pseudo-NaN ? */ 403 reg_copy(&CONST_QNaN, a);
404 { 404 }
405 reg_copy(&CONST_QNaN, a); 405 /* ensure a Quiet NaN */
406 a->sigh |= 0x40000000;
406 } 407 }
407 /* ensure a Quiet NaN */
408 a->sigh |= 0x40000000;
409 }
410 408
411 EXCEPTION(EX_Invalid); 409 EXCEPTION(EX_Invalid);
412 410
413 return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Special; 411 return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Special;
414} 412}
415 413
416
417/* Real operation attempted on two operands, one a NaN. */ 414/* Real operation attempted on two operands, one a NaN. */
418/* Returns < 0 if the exception is unmasked */ 415/* Returns < 0 if the exception is unmasked */
419int real_2op_NaN(FPU_REG const *b, u_char tagb, 416int real_2op_NaN(FPU_REG const *b, u_char tagb,
420 int deststnr, 417 int deststnr, FPU_REG const *defaultNaN)
421 FPU_REG const *defaultNaN)
422{ 418{
423 FPU_REG *dest = &st(deststnr); 419 FPU_REG *dest = &st(deststnr);
424 FPU_REG const *a = dest; 420 FPU_REG const *a = dest;
425 u_char taga = FPU_gettagi(deststnr); 421 u_char taga = FPU_gettagi(deststnr);
426 FPU_REG const *x; 422 FPU_REG const *x;
427 int signalling, unsupported; 423 int signalling, unsupported;
428 424
429 if ( taga == TAG_Special ) 425 if (taga == TAG_Special)
430 taga = FPU_Special(a); 426 taga = FPU_Special(a);
431 if ( tagb == TAG_Special ) 427 if (tagb == TAG_Special)
432 tagb = FPU_Special(b); 428 tagb = FPU_Special(b);
433 429
434 /* TW_NaN is also used for unsupported data types. */ 430 /* TW_NaN is also used for unsupported data types. */
435 unsupported = ((taga == TW_NaN) 431 unsupported = ((taga == TW_NaN)
436 && !((exponent(a) == EXP_OVER) && (a->sigh & 0x80000000))) 432 && !((exponent(a) == EXP_OVER)
437 || ((tagb == TW_NaN) 433 && (a->sigh & 0x80000000)))
438 && !((exponent(b) == EXP_OVER) && (b->sigh & 0x80000000))); 434 || ((tagb == TW_NaN)
439 if ( unsupported ) 435 && !((exponent(b) == EXP_OVER) && (b->sigh & 0x80000000)));
440 { 436 if (unsupported) {
441 if ( control_word & CW_Invalid ) 437 if (control_word & CW_Invalid) {
442 { 438 /* Masked response */
443 /* Masked response */ 439 FPU_copy_to_regi(&CONST_QNaN, TAG_Special, deststnr);
444 FPU_copy_to_regi(&CONST_QNaN, TAG_Special, deststnr); 440 }
445 } 441 EXCEPTION(EX_Invalid);
446 EXCEPTION(EX_Invalid); 442 return (!(control_word & CW_Invalid) ? FPU_Exception : 0) |
447 return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Special; 443 TAG_Special;
448 }
449
450 if (taga == TW_NaN)
451 {
452 x = a;
453 if (tagb == TW_NaN)
454 {
455 signalling = !(a->sigh & b->sigh & 0x40000000);
456 if ( significand(b) > significand(a) )
457 x = b;
458 else if ( significand(b) == significand(a) )
459 {
460 /* The default result for the case of two "equal" NaNs (signs may
461 differ) is chosen to reproduce 80486 behaviour */
462 x = defaultNaN;
463 }
464 }
465 else
466 {
467 /* return the quiet version of the NaN in a */
468 signalling = !(a->sigh & 0x40000000);
469 } 444 }
470 } 445
471 else 446 if (taga == TW_NaN) {
447 x = a;
448 if (tagb == TW_NaN) {
449 signalling = !(a->sigh & b->sigh & 0x40000000);
450 if (significand(b) > significand(a))
451 x = b;
452 else if (significand(b) == significand(a)) {
453 /* The default result for the case of two "equal" NaNs (signs may
454 differ) is chosen to reproduce 80486 behaviour */
455 x = defaultNaN;
456 }
457 } else {
458 /* return the quiet version of the NaN in a */
459 signalling = !(a->sigh & 0x40000000);
460 }
461 } else
472#ifdef PARANOID 462#ifdef PARANOID
473 if (tagb == TW_NaN) 463 if (tagb == TW_NaN)
474#endif /* PARANOID */ 464#endif /* PARANOID */
475 { 465 {
476 signalling = !(b->sigh & 0x40000000); 466 signalling = !(b->sigh & 0x40000000);
477 x = b; 467 x = b;
478 } 468 }
479#ifdef PARANOID 469#ifdef PARANOID
480 else 470 else {
481 { 471 signalling = 0;
482 signalling = 0; 472 EXCEPTION(EX_INTERNAL | 0x113);
483 EXCEPTION(EX_INTERNAL|0x113); 473 x = &CONST_QNaN;
484 x = &CONST_QNaN; 474 }
485 }
486#endif /* PARANOID */ 475#endif /* PARANOID */
487 476
488 if ( (!signalling) || (control_word & CW_Invalid) ) 477 if ((!signalling) || (control_word & CW_Invalid)) {
489 { 478 if (!x)
490 if ( ! x ) 479 x = b;
491 x = b;
492 480
493 if ( !(x->sigh & 0x80000000) ) /* pseudo-NaN ? */ 481 if (!(x->sigh & 0x80000000)) /* pseudo-NaN ? */
494 x = &CONST_QNaN; 482 x = &CONST_QNaN;
495 483
496 FPU_copy_to_regi(x, TAG_Special, deststnr); 484 FPU_copy_to_regi(x, TAG_Special, deststnr);
497 485
498 if ( !signalling ) 486 if (!signalling)
499 return TAG_Special; 487 return TAG_Special;
500 488
501 /* ensure a Quiet NaN */ 489 /* ensure a Quiet NaN */
502 dest->sigh |= 0x40000000; 490 dest->sigh |= 0x40000000;
503 } 491 }
504 492
505 EXCEPTION(EX_Invalid); 493 EXCEPTION(EX_Invalid);
506 494
507 return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Special; 495 return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Special;
508} 496}
509 497
510
511/* Invalid arith operation on Valid registers */ 498/* Invalid arith operation on Valid registers */
512/* Returns < 0 if the exception is unmasked */ 499/* Returns < 0 if the exception is unmasked */
513asmlinkage int arith_invalid(int deststnr) 500asmlinkage int arith_invalid(int deststnr)
514{ 501{
515 502
516 EXCEPTION(EX_Invalid); 503 EXCEPTION(EX_Invalid);
517
518 if ( control_word & CW_Invalid )
519 {
520 /* The masked response */
521 FPU_copy_to_regi(&CONST_QNaN, TAG_Special, deststnr);
522 }
523
524 return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Valid;
525 504
526} 505 if (control_word & CW_Invalid) {
506 /* The masked response */
507 FPU_copy_to_regi(&CONST_QNaN, TAG_Special, deststnr);
508 }
527 509
510 return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Valid;
511
512}
528 513
529/* Divide a finite number by zero */ 514/* Divide a finite number by zero */
530asmlinkage int FPU_divide_by_zero(int deststnr, u_char sign) 515asmlinkage int FPU_divide_by_zero(int deststnr, u_char sign)
531{ 516{
532 FPU_REG *dest = &st(deststnr); 517 FPU_REG *dest = &st(deststnr);
533 int tag = TAG_Valid; 518 int tag = TAG_Valid;
519
520 if (control_word & CW_ZeroDiv) {
521 /* The masked response */
522 FPU_copy_to_regi(&CONST_INF, TAG_Special, deststnr);
523 setsign(dest, sign);
524 tag = TAG_Special;
525 }
534 526
535 if ( control_word & CW_ZeroDiv ) 527 EXCEPTION(EX_ZeroDiv);
536 {
537 /* The masked response */
538 FPU_copy_to_regi(&CONST_INF, TAG_Special, deststnr);
539 setsign(dest, sign);
540 tag = TAG_Special;
541 }
542
543 EXCEPTION(EX_ZeroDiv);
544 528
545 return (!(control_word & CW_ZeroDiv) ? FPU_Exception : 0) | tag; 529 return (!(control_word & CW_ZeroDiv) ? FPU_Exception : 0) | tag;
546 530
547} 531}
548 532
549
550/* This may be called often, so keep it lean */ 533/* This may be called often, so keep it lean */
551int set_precision_flag(int flags) 534int set_precision_flag(int flags)
552{ 535{
553 if ( control_word & CW_Precision ) 536 if (control_word & CW_Precision) {
554 { 537 partial_status &= ~(SW_C1 & flags);
555 partial_status &= ~(SW_C1 & flags); 538 partial_status |= flags; /* The masked response */
556 partial_status |= flags; /* The masked response */ 539 return 0;
557 return 0; 540 } else {
558 } 541 EXCEPTION(flags);
559 else 542 return 1;
560 { 543 }
561 EXCEPTION(flags);
562 return 1;
563 }
564} 544}
565 545
566
567/* This may be called often, so keep it lean */ 546/* This may be called often, so keep it lean */
568asmlinkage void set_precision_flag_up(void) 547asmlinkage void set_precision_flag_up(void)
569{ 548{
570 if ( control_word & CW_Precision ) 549 if (control_word & CW_Precision)
571 partial_status |= (SW_Precision | SW_C1); /* The masked response */ 550 partial_status |= (SW_Precision | SW_C1); /* The masked response */
572 else 551 else
573 EXCEPTION(EX_Precision | SW_C1); 552 EXCEPTION(EX_Precision | SW_C1);
574} 553}
575 554
576
577/* This may be called often, so keep it lean */ 555/* This may be called often, so keep it lean */
578asmlinkage void set_precision_flag_down(void) 556asmlinkage void set_precision_flag_down(void)
579{ 557{
580 if ( control_word & CW_Precision ) 558 if (control_word & CW_Precision) { /* The masked response */
581 { /* The masked response */ 559 partial_status &= ~SW_C1;
582 partial_status &= ~SW_C1; 560 partial_status |= SW_Precision;
583 partial_status |= SW_Precision; 561 } else
584 } 562 EXCEPTION(EX_Precision);
585 else
586 EXCEPTION(EX_Precision);
587} 563}
588 564
589
590asmlinkage int denormal_operand(void) 565asmlinkage int denormal_operand(void)
591{ 566{
592 if ( control_word & CW_Denormal ) 567 if (control_word & CW_Denormal) { /* The masked response */
593 { /* The masked response */ 568 partial_status |= SW_Denorm_Op;
594 partial_status |= SW_Denorm_Op; 569 return TAG_Special;
595 return TAG_Special; 570 } else {
596 } 571 EXCEPTION(EX_Denormal);
597 else 572 return TAG_Special | FPU_Exception;
598 { 573 }
599 EXCEPTION(EX_Denormal);
600 return TAG_Special | FPU_Exception;
601 }
602} 574}
603 575
604 576asmlinkage int arith_overflow(FPU_REG * dest)
605asmlinkage int arith_overflow(FPU_REG *dest)
606{ 577{
607 int tag = TAG_Valid; 578 int tag = TAG_Valid;
608 579
609 if ( control_word & CW_Overflow ) 580 if (control_word & CW_Overflow) {
610 { 581 /* The masked response */
611 /* The masked response */
612/* ###### The response here depends upon the rounding mode */ 582/* ###### The response here depends upon the rounding mode */
613 reg_copy(&CONST_INF, dest); 583 reg_copy(&CONST_INF, dest);
614 tag = TAG_Special; 584 tag = TAG_Special;
615 } 585 } else {
616 else 586 /* Subtract the magic number from the exponent */
617 { 587 addexponent(dest, (-3 * (1 << 13)));
618 /* Subtract the magic number from the exponent */ 588 }
619 addexponent(dest, (-3 * (1 << 13)));
620 }
621
622 EXCEPTION(EX_Overflow);
623 if ( control_word & CW_Overflow )
624 {
625 /* The overflow exception is masked. */
626 /* By definition, precision is lost.
627 The roundup bit (C1) is also set because we have
628 "rounded" upwards to Infinity. */
629 EXCEPTION(EX_Precision | SW_C1);
630 return tag;
631 }
632
633 return tag;
634 589
635} 590 EXCEPTION(EX_Overflow);
591 if (control_word & CW_Overflow) {
592 /* The overflow exception is masked. */
593 /* By definition, precision is lost.
594 The roundup bit (C1) is also set because we have
595 "rounded" upwards to Infinity. */
596 EXCEPTION(EX_Precision | SW_C1);
597 return tag;
598 }
636 599
600 return tag;
637 601
638asmlinkage int arith_underflow(FPU_REG *dest) 602}
639{
640 int tag = TAG_Valid;
641 603
642 if ( control_word & CW_Underflow ) 604asmlinkage int arith_underflow(FPU_REG * dest)
643 { 605{
644 /* The masked response */ 606 int tag = TAG_Valid;
645 if ( exponent16(dest) <= EXP_UNDER - 63 ) 607
646 { 608 if (control_word & CW_Underflow) {
647 reg_copy(&CONST_Z, dest); 609 /* The masked response */
648 partial_status &= ~SW_C1; /* Round down. */ 610 if (exponent16(dest) <= EXP_UNDER - 63) {
649 tag = TAG_Zero; 611 reg_copy(&CONST_Z, dest);
612 partial_status &= ~SW_C1; /* Round down. */
613 tag = TAG_Zero;
614 } else {
615 stdexp(dest);
616 }
617 } else {
618 /* Add the magic number to the exponent. */
619 addexponent(dest, (3 * (1 << 13)) + EXTENDED_Ebias);
650 } 620 }
651 else 621
652 { 622 EXCEPTION(EX_Underflow);
653 stdexp(dest); 623 if (control_word & CW_Underflow) {
624 /* The underflow exception is masked. */
625 EXCEPTION(EX_Precision);
626 return tag;
654 } 627 }
655 }
656 else
657 {
658 /* Add the magic number to the exponent. */
659 addexponent(dest, (3 * (1 << 13)) + EXTENDED_Ebias);
660 }
661
662 EXCEPTION(EX_Underflow);
663 if ( control_word & CW_Underflow )
664 {
665 /* The underflow exception is masked. */
666 EXCEPTION(EX_Precision);
667 return tag;
668 }
669
670 return tag;
671 628
672} 629 return tag;
673 630
631}
674 632
675void FPU_stack_overflow(void) 633void FPU_stack_overflow(void)
676{ 634{
677 635
678 if ( control_word & CW_Invalid ) 636 if (control_word & CW_Invalid) {
679 { 637 /* The masked response */
680 /* The masked response */ 638 top--;
681 top--; 639 FPU_copy_to_reg0(&CONST_QNaN, TAG_Special);
682 FPU_copy_to_reg0(&CONST_QNaN, TAG_Special); 640 }
683 }
684 641
685 EXCEPTION(EX_StackOver); 642 EXCEPTION(EX_StackOver);
686 643
687 return; 644 return;
688 645
689} 646}
690 647
691
692void FPU_stack_underflow(void) 648void FPU_stack_underflow(void)
693{ 649{
694 650
695 if ( control_word & CW_Invalid ) 651 if (control_word & CW_Invalid) {
696 { 652 /* The masked response */
697 /* The masked response */ 653 FPU_copy_to_reg0(&CONST_QNaN, TAG_Special);
698 FPU_copy_to_reg0(&CONST_QNaN, TAG_Special); 654 }
699 }
700 655
701 EXCEPTION(EX_StackUnder); 656 EXCEPTION(EX_StackUnder);
702 657
703 return; 658 return;
704 659
705} 660}
706 661
707
708void FPU_stack_underflow_i(int i) 662void FPU_stack_underflow_i(int i)
709{ 663{
710 664
711 if ( control_word & CW_Invalid ) 665 if (control_word & CW_Invalid) {
712 { 666 /* The masked response */
713 /* The masked response */ 667 FPU_copy_to_regi(&CONST_QNaN, TAG_Special, i);
714 FPU_copy_to_regi(&CONST_QNaN, TAG_Special, i); 668 }
715 }
716 669
717 EXCEPTION(EX_StackUnder); 670 EXCEPTION(EX_StackUnder);
718 671
719 return; 672 return;
720 673
721} 674}
722 675
723
724void FPU_stack_underflow_pop(int i) 676void FPU_stack_underflow_pop(int i)
725{ 677{
726 678
727 if ( control_word & CW_Invalid ) 679 if (control_word & CW_Invalid) {
728 { 680 /* The masked response */
729 /* The masked response */ 681 FPU_copy_to_regi(&CONST_QNaN, TAG_Special, i);
730 FPU_copy_to_regi(&CONST_QNaN, TAG_Special, i); 682 FPU_pop();
731 FPU_pop(); 683 }
732 }
733 684
734 EXCEPTION(EX_StackUnder); 685 EXCEPTION(EX_StackUnder);
735 686
736 return; 687 return;
737 688
738} 689}
739