Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 686 insertions, 0 deletions

diff --git a/arch/x86/math-emu/errors.c b/arch/x86/math-emu/errors.c
new file mode 100644
index 000000000..ec071cbb0
--- /dev/null
+++ b/arch/x86/math-emu/errors.c
@@ -0,0 +1,686 @@
+// SPDX-License-Identifier: GPL-2.0
+/*---------------------------------------------------------------------------+
+ |  errors.c                                                                 |
+ |                                                                           |
+ |  The error handling functions for wm-FPU-emu                              |
+ |                                                                           |
+ | Copyright (C) 1992,1993,1994,1996                                         |
+ |                  W. Metzenthen, 22 Parker St, Ormond, Vic 3163, Australia |
+ |                  E-mail   billm@jacobi.maths.monash.edu.au                |
+ |                                                                           |
+ |                                                                           |
+ +---------------------------------------------------------------------------*/
+
+/*---------------------------------------------------------------------------+
+ | Note:                                                                     |
+ |    The file contains code which accesses user memory.                     |
+ |    Emulator static data may change when user memory is accessed, due to   |
+ |    other processes using the emulator while swapping is in progress.      |
+ +---------------------------------------------------------------------------*/
+
+#include <linux/signal.h>
+
+#include <linux/uaccess.h>
+
+#include "fpu_emu.h"
+#include "fpu_system.h"
+#include "exception.h"
+#include "status_w.h"
+#include "control_w.h"
+#include "reg_constant.h"
+#include "version.h"
+
+/* */
+#undef PRINT_MESSAGES
+/* */
+
+#if 0
+void Un_impl(void)
+{
+	u_char byte1, FPU_modrm;
+	unsigned long address = FPU_ORIG_EIP;
+
+	RE_ENTRANT_CHECK_OFF;
+	/* No need to check access_ok(), we have previously fetched these bytes. */
+	printk("Unimplemented FPU Opcode at eip=%p : ", (void __user *)address);
+	if (FPU_CS == __USER_CS) {
+		while (1) {
+			FPU_get_user(byte1, (u_char __user *) address);
+			if ((byte1 & 0xf8) == 0xd8)
+				break;
+			printk("[%02x]", byte1);
+			address++;
+		}
+		printk("%02x ", byte1);
+		FPU_get_user(FPU_modrm, 1 + (u_char __user *) address);
+
+		if (FPU_modrm >= 0300)
+			printk("%02x (%02x+%d)\n", FPU_modrm, FPU_modrm & 0xf8,
+			       FPU_modrm & 7);
+		else
+			printk("/%d\n", (FPU_modrm >> 3) & 7);
+	} else {
+		printk("cs selector = %04x\n", FPU_CS);
+	}
+
+	RE_ENTRANT_CHECK_ON;
+
+	EXCEPTION(EX_Invalid);
+
+}
+#endif /*  0  */
+
+/*
+   Called for opcodes which are illegal and which are known to result in a
+   SIGILL with a real 80486.
+   */
+void FPU_illegal(void)
+{
+	math_abort(FPU_info, SIGILL);
+}
+
+void FPU_printall(void)
+{
+	int i;
+	static const char *tag_desc[] = { "Valid", "Zero", "ERROR", "Empty",
+		"DeNorm", "Inf", "NaN"
+	};
+	u_char byte1, FPU_modrm;
+	unsigned long address = FPU_ORIG_EIP;
+
+	RE_ENTRANT_CHECK_OFF;
+	/* No need to check access_ok(), we have previously fetched these bytes. */
+	printk("At %p:", (void *)address);
+	if (FPU_CS == __USER_CS) {
+#define MAX_PRINTED_BYTES 20
+		for (i = 0; i < MAX_PRINTED_BYTES; i++) {
+			FPU_get_user(byte1, (u_char __user *) address);
+			if ((byte1 & 0xf8) == 0xd8) {
+				printk(" %02x", byte1);
+				break;
+			}
+			printk(" [%02x]", byte1);
+			address++;
+		}
+		if (i == MAX_PRINTED_BYTES)
+			printk(" [more..]\n");
+		else {
+			FPU_get_user(FPU_modrm, 1 + (u_char __user *) address);
+
+			if (FPU_modrm >= 0300)
+				printk(" %02x (%02x+%d)\n", FPU_modrm,
+				       FPU_modrm & 0xf8, FPU_modrm & 7);
+			else
+				printk(" /%d, mod=%d rm=%d\n",
+				       (FPU_modrm >> 3) & 7,
+				       (FPU_modrm >> 6) & 3, FPU_modrm & 7);
+		}
+	} else {
+		printk("%04x\n", FPU_CS);
+	}
+
+	partial_status = status_word();
+
+#ifdef DEBUGGING
+	if (partial_status & SW_Backward)
+		printk("SW: backward compatibility\n");
+	if (partial_status & SW_C3)
+		printk("SW: condition bit 3\n");
+	if (partial_status & SW_C2)
+		printk("SW: condition bit 2\n");
+	if (partial_status & SW_C1)
+		printk("SW: condition bit 1\n");
+	if (partial_status & SW_C0)
+		printk("SW: condition bit 0\n");
+	if (partial_status & SW_Summary)
+		printk("SW: exception summary\n");
+	if (partial_status & SW_Stack_Fault)
+		printk("SW: stack fault\n");
+	if (partial_status & SW_Precision)
+		printk("SW: loss of precision\n");
+	if (partial_status & SW_Underflow)
+		printk("SW: underflow\n");
+	if (partial_status & SW_Overflow)
+		printk("SW: overflow\n");
+	if (partial_status & SW_Zero_Div)
+		printk("SW: divide by zero\n");
+	if (partial_status & SW_Denorm_Op)
+		printk("SW: denormalized operand\n");
+	if (partial_status & SW_Invalid)
+		printk("SW: invalid operation\n");
+#endif /* DEBUGGING */
+
+	printk(" SW: b=%d st=%d es=%d sf=%d cc=%d%d%d%d ef=%d%d%d%d%d%d\n", partial_status & 0x8000 ? 1 : 0,	/* busy */
+	       (partial_status & 0x3800) >> 11,	/* stack top pointer */
+	       partial_status & 0x80 ? 1 : 0,	/* Error summary status */
+	       partial_status & 0x40 ? 1 : 0,	/* Stack flag */
+	       partial_status & SW_C3 ? 1 : 0, partial_status & SW_C2 ? 1 : 0,	/* cc */
+	       partial_status & SW_C1 ? 1 : 0, partial_status & SW_C0 ? 1 : 0,	/* cc */
+	       partial_status & SW_Precision ? 1 : 0,
+	       partial_status & SW_Underflow ? 1 : 0,
+	       partial_status & SW_Overflow ? 1 : 0,
+	       partial_status & SW_Zero_Div ? 1 : 0,
+	       partial_status & SW_Denorm_Op ? 1 : 0,
+	       partial_status & SW_Invalid ? 1 : 0);
+
+	printk(" CW: ic=%d rc=%d%d pc=%d%d iem=%d     ef=%d%d%d%d%d%d\n",
+	       control_word & 0x1000 ? 1 : 0,
+	       (control_word & 0x800) >> 11, (control_word & 0x400) >> 10,
+	       (control_word & 0x200) >> 9, (control_word & 0x100) >> 8,
+	       control_word & 0x80 ? 1 : 0,
+	       control_word & SW_Precision ? 1 : 0,
+	       control_word & SW_Underflow ? 1 : 0,
+	       control_word & SW_Overflow ? 1 : 0,
+	       control_word & SW_Zero_Div ? 1 : 0,
+	       control_word & SW_Denorm_Op ? 1 : 0,
+	       control_word & SW_Invalid ? 1 : 0);
+
+	for (i = 0; i < 8; i++) {
+		FPU_REG *r = &st(i);
+		u_char tagi = FPU_gettagi(i);
+
+		switch (tagi) {
+		case TAG_Empty:
+			continue;
+		case TAG_Zero:
+		case TAG_Special:
+			/* Update tagi for the printk below */
+			tagi = FPU_Special(r);
+			fallthrough;
+		case TAG_Valid:
+			printk("st(%d)  %c .%04lx %04lx %04lx %04lx e%+-6d ", i,
+			       getsign(r) ? '-' : '+',
+			       (long)(r->sigh >> 16),
+			       (long)(r->sigh & 0xFFFF),
+			       (long)(r->sigl >> 16),
+			       (long)(r->sigl & 0xFFFF),
+			       exponent(r) - EXP_BIAS + 1);
+			break;
+		default:
+			printk("Whoops! Error in errors.c: tag%d is %d ", i,
+			       tagi);
+			continue;
+		}
+		printk("%s\n", tag_desc[(int)(unsigned)tagi]);
+	}
+
+	RE_ENTRANT_CHECK_ON;
+
+}
+
+static struct {
+	int type;
+	const char *name;
+} exception_names[] = {
+	{
+	EX_StackOver, "stack overflow"}, {
+	EX_StackUnder, "stack underflow"}, {
+	EX_Precision, "loss of precision"}, {
+	EX_Underflow, "underflow"}, {
+	EX_Overflow, "overflow"}, {
+	EX_ZeroDiv, "divide by zero"}, {
+	EX_Denormal, "denormalized operand"}, {
+	EX_Invalid, "invalid operation"}, {
+	EX_INTERNAL, "INTERNAL BUG in " FPU_VERSION}, {
+	0, NULL}
+};
+
+/*
+ EX_INTERNAL is always given with a code which indicates where the
+ error was detected.
+
+ Internal error types:
+       0x14   in fpu_etc.c
+       0x1nn  in a *.c file:
+              0x101  in reg_add_sub.c
+              0x102  in reg_mul.c
+              0x104  in poly_atan.c
+              0x105  in reg_mul.c
+              0x107  in fpu_trig.c
+	      0x108  in reg_compare.c
+	      0x109  in reg_compare.c
+	      0x110  in reg_add_sub.c
+	      0x111  in fpe_entry.c
+	      0x112  in fpu_trig.c
+	      0x113  in errors.c
+	      0x115  in fpu_trig.c
+	      0x116  in fpu_trig.c
+	      0x117  in fpu_trig.c
+	      0x118  in fpu_trig.c
+	      0x119  in fpu_trig.c
+	      0x120  in poly_atan.c
+	      0x121  in reg_compare.c
+	      0x122  in reg_compare.c
+	      0x123  in reg_compare.c
+	      0x125  in fpu_trig.c
+	      0x126  in fpu_entry.c
+	      0x127  in poly_2xm1.c
+	      0x128  in fpu_entry.c
+	      0x129  in fpu_entry.c
+	      0x130  in get_address.c
+	      0x131  in get_address.c
+	      0x132  in get_address.c
+	      0x133  in get_address.c
+	      0x140  in load_store.c
+	      0x141  in load_store.c
+              0x150  in poly_sin.c
+              0x151  in poly_sin.c
+	      0x160  in reg_ld_str.c
+	      0x161  in reg_ld_str.c
+	      0x162  in reg_ld_str.c
+	      0x163  in reg_ld_str.c
+	      0x164  in reg_ld_str.c
+	      0x170  in fpu_tags.c
+	      0x171  in fpu_tags.c
+	      0x172  in fpu_tags.c
+	      0x180  in reg_convert.c
+       0x2nn  in an *.S file:
+              0x201  in reg_u_add.S
+              0x202  in reg_u_div.S
+              0x203  in reg_u_div.S
+              0x204  in reg_u_div.S
+              0x205  in reg_u_mul.S
+              0x206  in reg_u_sub.S
+              0x207  in wm_sqrt.S
+	      0x208  in reg_div.S
+              0x209  in reg_u_sub.S
+              0x210  in reg_u_sub.S
+              0x211  in reg_u_sub.S
+              0x212  in reg_u_sub.S
+	      0x213  in wm_sqrt.S
+	      0x214  in wm_sqrt.S
+	      0x215  in wm_sqrt.S
+	      0x220  in reg_norm.S
+	      0x221  in reg_norm.S
+	      0x230  in reg_round.S
+	      0x231  in reg_round.S
+	      0x232  in reg_round.S
+	      0x233  in reg_round.S
+	      0x234  in reg_round.S
+	      0x235  in reg_round.S
+	      0x236  in reg_round.S
+	      0x240  in div_Xsig.S
+	      0x241  in div_Xsig.S
+	      0x242  in div_Xsig.S
+ */
+
+asmlinkage __visible void FPU_exception(int n)
+{
+	int i, int_type;
+
+	int_type = 0;		/* Needed only to stop compiler warnings */
+	if (n & EX_INTERNAL) {
+		int_type = n - EX_INTERNAL;
+		n = EX_INTERNAL;
+		/* Set lots of exception bits! */
+		partial_status |= (SW_Exc_Mask | SW_Summary | SW_Backward);
+	} else {
+		/* Extract only the bits which we use to set the status word */
+		n &= (SW_Exc_Mask);
+		/* Set the corresponding exception bit */
+		partial_status |= n;
+		/* Set summary bits iff exception isn't masked */
+		if (partial_status & ~control_word & CW_Exceptions)
+			partial_status |= (SW_Summary | SW_Backward);
+		if (n & (SW_Stack_Fault | EX_Precision)) {
+			if (!(n & SW_C1))
+				/* This bit distinguishes over- from underflow for a stack fault,
+				   and roundup from round-down for precision loss. */
+				partial_status &= ~SW_C1;
+		}
+	}
+
+	RE_ENTRANT_CHECK_OFF;
+	if ((~control_word & n & CW_Exceptions) || (n == EX_INTERNAL)) {
+		/* Get a name string for error reporting */
+		for (i = 0; exception_names[i].type; i++)
+			if ((exception_names[i].type & n) ==
+			    exception_names[i].type)
+				break;
+
+		if (exception_names[i].type) {
+#ifdef PRINT_MESSAGES
+			printk("FP Exception: %s!\n", exception_names[i].name);
+#endif /* PRINT_MESSAGES */
+		} else
+			printk("FPU emulator: Unknown Exception: 0x%04x!\n", n);
+
+		if (n == EX_INTERNAL) {
+			printk("FPU emulator: Internal error type 0x%04x\n",
+			       int_type);
+			FPU_printall();
+		}
+#ifdef PRINT_MESSAGES
+		else
+			FPU_printall();
+#endif /* PRINT_MESSAGES */
+
+		/*
+		 * The 80486 generates an interrupt on the next non-control FPU
+		 * instruction. So we need some means of flagging it.
+		 * We use the ES (Error Summary) bit for this.
+		 */
+	}
+	RE_ENTRANT_CHECK_ON;
+
+#ifdef __DEBUG__
+	math_abort(FPU_info, SIGFPE);
+#endif /* __DEBUG__ */
+
+}
+
+/* Real operation attempted on a NaN. */
+/* Returns < 0 if the exception is unmasked */
+int real_1op_NaN(FPU_REG *a)
+{
+	int signalling, isNaN;
+
+	isNaN = (exponent(a) == EXP_OVER) && (a->sigh & 0x80000000);
+
+	/* The default result for the case of two "equal" NaNs (signs may
+	   differ) is chosen to reproduce 80486 behaviour */
+	signalling = isNaN && !(a->sigh & 0x40000000);
+
+	if (!signalling) {
+		if (!isNaN) {	/* pseudo-NaN, or other unsupported? */
+			if (control_word & CW_Invalid) {
+				/* Masked response */
+				reg_copy(&CONST_QNaN, a);
+			}
+			EXCEPTION(EX_Invalid);
+			return (!(control_word & CW_Invalid) ? FPU_Exception :
+				0) | TAG_Special;
+		}
+		return TAG_Special;
+	}
+
+	if (control_word & CW_Invalid) {
+		/* The masked response */
+		if (!(a->sigh & 0x80000000)) {	/* pseudo-NaN ? */
+			reg_copy(&CONST_QNaN, a);
+		}
+		/* ensure a Quiet NaN */
+		a->sigh |= 0x40000000;
+	}
+
+	EXCEPTION(EX_Invalid);
+
+	return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Special;
+}
+
+/* Real operation attempted on two operands, one a NaN. */
+/* Returns < 0 if the exception is unmasked */
+int real_2op_NaN(FPU_REG const *b, u_char tagb,
+		 int deststnr, FPU_REG const *defaultNaN)
+{
+	FPU_REG *dest = &st(deststnr);
+	FPU_REG const *a = dest;
+	u_char taga = FPU_gettagi(deststnr);
+	FPU_REG const *x;
+	int signalling, unsupported;
+
+	if (taga == TAG_Special)
+		taga = FPU_Special(a);
+	if (tagb == TAG_Special)
+		tagb = FPU_Special(b);
+
+	/* TW_NaN is also used for unsupported data types. */
+	unsupported = ((taga == TW_NaN)
+		       && !((exponent(a) == EXP_OVER)
+			    && (a->sigh & 0x80000000)))
+	    || ((tagb == TW_NaN)
+		&& !((exponent(b) == EXP_OVER) && (b->sigh & 0x80000000)));
+	if (unsupported) {
+		if (control_word & CW_Invalid) {
+			/* Masked response */
+			FPU_copy_to_regi(&CONST_QNaN, TAG_Special, deststnr);
+		}
+		EXCEPTION(EX_Invalid);
+		return (!(control_word & CW_Invalid) ? FPU_Exception : 0) |
+		    TAG_Special;
+	}
+
+	if (taga == TW_NaN) {
+		x = a;
+		if (tagb == TW_NaN) {
+			signalling = !(a->sigh & b->sigh & 0x40000000);
+			if (significand(b) > significand(a))
+				x = b;
+			else if (significand(b) == significand(a)) {
+				/* The default result for the case of two "equal" NaNs (signs may
+				   differ) is chosen to reproduce 80486 behaviour */
+				x = defaultNaN;
+			}
+		} else {
+			/* return the quiet version of the NaN in a */
+			signalling = !(a->sigh & 0x40000000);
+		}
+	} else
+#ifdef PARANOID
+	if (tagb == TW_NaN)
+#endif /* PARANOID */
+	{
+		signalling = !(b->sigh & 0x40000000);
+		x = b;
+	}
+#ifdef PARANOID
+	else {
+		signalling = 0;
+		EXCEPTION(EX_INTERNAL | 0x113);
+		x = &CONST_QNaN;
+	}
+#endif /* PARANOID */
+
+	if ((!signalling) || (control_word & CW_Invalid)) {
+		if (!x)
+			x = b;
+
+		if (!(x->sigh & 0x80000000))	/* pseudo-NaN ? */
+			x = &CONST_QNaN;
+
+		FPU_copy_to_regi(x, TAG_Special, deststnr);
+
+		if (!signalling)
+			return TAG_Special;
+
+		/* ensure a Quiet NaN */
+		dest->sigh |= 0x40000000;
+	}
+
+	EXCEPTION(EX_Invalid);
+
+	return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Special;
+}
+
+/* Invalid arith operation on Valid registers */
+/* Returns < 0 if the exception is unmasked */
+asmlinkage __visible int arith_invalid(int deststnr)
+{
+
+	EXCEPTION(EX_Invalid);
+
+	if (control_word & CW_Invalid) {
+		/* The masked response */
+		FPU_copy_to_regi(&CONST_QNaN, TAG_Special, deststnr);
+	}
+
+	return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Valid;
+
+}
+
+/* Divide a finite number by zero */
+asmlinkage __visible int FPU_divide_by_zero(int deststnr, u_char sign)
+{
+	FPU_REG *dest = &st(deststnr);
+	int tag = TAG_Valid;
+
+	if (control_word & CW_ZeroDiv) {
+		/* The masked response */
+		FPU_copy_to_regi(&CONST_INF, TAG_Special, deststnr);
+		setsign(dest, sign);
+		tag = TAG_Special;
+	}
+
+	EXCEPTION(EX_ZeroDiv);
+
+	return (!(control_word & CW_ZeroDiv) ? FPU_Exception : 0) | tag;
+
+}
+
+/* This may be called often, so keep it lean */
+int set_precision_flag(int flags)
+{
+	if (control_word & CW_Precision) {
+		partial_status &= ~(SW_C1 & flags);
+		partial_status |= flags;	/* The masked response */
+		return 0;
+	} else {
+		EXCEPTION(flags);
+		return 1;
+	}
+}
+
+/* This may be called often, so keep it lean */
+asmlinkage __visible void set_precision_flag_up(void)
+{
+	if (control_word & CW_Precision)
+		partial_status |= (SW_Precision | SW_C1);	/* The masked response */
+	else
+		EXCEPTION(EX_Precision | SW_C1);
+}
+
+/* This may be called often, so keep it lean */
+asmlinkage __visible void set_precision_flag_down(void)
+{
+	if (control_word & CW_Precision) {	/* The masked response */
+		partial_status &= ~SW_C1;
+		partial_status |= SW_Precision;
+	} else
+		EXCEPTION(EX_Precision);
+}
+
+asmlinkage __visible int denormal_operand(void)
+{
+	if (control_word & CW_Denormal) {	/* The masked response */
+		partial_status |= SW_Denorm_Op;
+		return TAG_Special;
+	} else {
+		EXCEPTION(EX_Denormal);
+		return TAG_Special | FPU_Exception;
+	}
+}
+
+asmlinkage __visible int arith_overflow(FPU_REG *dest)
+{
+	int tag = TAG_Valid;
+
+	if (control_word & CW_Overflow) {
+		/* The masked response */
+/* ###### The response here depends upon the rounding mode */
+		reg_copy(&CONST_INF, dest);
+		tag = TAG_Special;
+	} else {
+		/* Subtract the magic number from the exponent */
+		addexponent(dest, (-3 * (1 << 13)));
+	}
+
+	EXCEPTION(EX_Overflow);
+	if (control_word & CW_Overflow) {
+		/* The overflow exception is masked. */
+		/* By definition, precision is lost.
+		   The roundup bit (C1) is also set because we have
+		   "rounded" upwards to Infinity. */
+		EXCEPTION(EX_Precision | SW_C1);
+		return tag;
+	}
+
+	return tag;
+
+}
+
+asmlinkage __visible int arith_underflow(FPU_REG *dest)
+{
+	int tag = TAG_Valid;
+
+	if (control_word & CW_Underflow) {
+		/* The masked response */
+		if (exponent16(dest) <= EXP_UNDER - 63) {
+			reg_copy(&CONST_Z, dest);
+			partial_status &= ~SW_C1;	/* Round down. */
+			tag = TAG_Zero;
+		} else {
+			stdexp(dest);
+		}
+	} else {
+		/* Add the magic number to the exponent. */
+		addexponent(dest, (3 * (1 << 13)) + EXTENDED_Ebias);
+	}
+
+	EXCEPTION(EX_Underflow);
+	if (control_word & CW_Underflow) {
+		/* The underflow exception is masked. */
+		EXCEPTION(EX_Precision);
+		return tag;
+	}
+
+	return tag;
+
+}
+
+void FPU_stack_overflow(void)
+{
+
+	if (control_word & CW_Invalid) {
+		/* The masked response */
+		top--;
+		FPU_copy_to_reg0(&CONST_QNaN, TAG_Special);
+	}
+
+	EXCEPTION(EX_StackOver);
+
+	return;
+
+}
+
+void FPU_stack_underflow(void)
+{
+
+	if (control_word & CW_Invalid) {
+		/* The masked response */
+		FPU_copy_to_reg0(&CONST_QNaN, TAG_Special);
+	}
+
+	EXCEPTION(EX_StackUnder);
+
+	return;
+
+}
+
+void FPU_stack_underflow_i(int i)
+{
+
+	if (control_word & CW_Invalid) {
+		/* The masked response */
+		FPU_copy_to_regi(&CONST_QNaN, TAG_Special, i);
+	}
+
+	EXCEPTION(EX_StackUnder);
+
+	return;
+
+}
+
+void FPU_stack_underflow_pop(int i)
+{
+
+	if (control_word & CW_Invalid) {
+		/* The masked response */
+		FPU_copy_to_regi(&CONST_QNaN, TAG_Special, i);
+		FPU_pop();
+	}
+
+	EXCEPTION(EX_StackUnder);
+
+	return;
+
+}