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NetBSD/sys/arch/pc532/fpu/ieee_handler.c

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/* $NetBSD: ieee_handler.c,v 1.2 1996/05/03 23:19:26 phil Exp $ */
/*
* IEEE floating point support for NS32081 and NS32381 fpus.
* Copyright (c) 1995 Ian Dall
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* IAN DALL ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" CONDITION.
* IAN DALL DISCLAIMS ANY LIABILITY OF ANY KIND FOR ANY DAMAGES
* WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*/
/*
* File: ieee_handler.c
* Author: Ian Dall
* Date: November 1995
*
* Entry points for the ieee exception handling package.
* decodes floating point instructions.
*
* HISTORY
* 23-Apr-96 Ian Dall (Ian.Dall@dsto.defence.gov.au)
* Advance pc past trapping instruction always.
*
* 13-Apr-96 Matthias Pfaller <leo@dachau.marco.de>
* Fix up test for denormalized result in canonical_to_size().
*
* 13-Apr-96 Ian Dall (Ian.Dall@dsto.defence.gov.au)
* Clean up types in get_operand().
*
* 13-Apr-96 Matthias Pfaller <leo@dachau.marco.de>
* Remove redundant status test code from fetch_data(). Fix
* register relative and PC relative address decoding.
*
* 02-Apr-96 Ian Dall (Ian.Dall@dsto.defence.gov.au)
* Make zero floats get canonicalized to doubles properly.
*
* 02-Apr-96 Ian Dall (Ian.Dall@dsto.defence.gov.au)
* Notice that default_trap_handle() has a side effect of changing
* state->FSR.
*
* 02-Apr-96 Matthias Pfaller <leo@dachau.marco.de>
* Add NetBSD kernel support.
*
* 14-Dec-95 Ian Dall (Ian.Dall@dsto.defence.gov.au)
* First release.
* */
#include <sys/types.h>
#include <stddef.h>
#include "ieee_internal.h"
#if defined(KERNEL) || defined(_KERNEL)
# ifdef MACH
# include <setjmp.h>
# define setjmp _setjmp
# define longjmp _longjmp
# define AT vm_offset_t
# elif defined(__NetBSD__) /* MACH */
# include <machine/param.h>
# include <sys/systm.h>
# define longjmp(x, y) longjmp(&x)
# define setjmp(x) setjmp(&x)
# define AT void *
# endif
# define get_dword(addr) ({long _t; COPYIN((addr), (vm_offset_t) &_t, sizeof(long)); _t;})
#else /* KERNEL */
# include <machine/param.h>
# include <setjmp.h>
# define AT vm_offset_t
# ifdef DEBUG
# include <stdio.h>
# endif
# define copyin(u,k,n) ({vm_offset_t _u = (u), _k = (k); memcpy((char *) _k, (char *) _u,n);0;})
# define copyout(k,u,n) ({vm_offset_t _u = (u), _k = (k); memcpy((char *) _u, (char *) _k,n);0;})
# define get_dword(addr) (* (unsigned int *) addr)
# define ns532_round_page(addr) (((addr) + NBPG - 1) & ~(NBPG - 1))
static void get_fstate(state *state) {
asm("sfsr %0" : "=g" (state->FSR));
asm("movl f0, %0" : "=m" (state->LREG(0)));
asm("movl f1, %0" : "=m" (state->LREG(1)));
asm("movl f2, %0" : "=m" (state->LREG(2)));
asm("movl f3, %0" : "=m" (state->LREG(3)));
asm("movl f4, %0" : "=m" (state->LREG(4)));
asm("movl f5, %0" : "=m" (state->LREG(5)));
asm("movl f6, %0" : "=m" (state->LREG(6)));
asm("movl f7, %0" : "=m" (state->LREG(7)));
}
static void set_fstate(state *state) {
/* DON'T tell gcc we are clobbering fp registers, else it will
* save and restore some, undoing our changes!
*/
asm("lfsr %0":: "g" (state->FSR));
asm("movl %0, f0":: "m" (state->LREG(0)));
asm("movl %0, f1":: "m" (state->LREG(1)));
asm("movl %0, f2":: "m" (state->LREG(2)));
asm("movl %0, f3":: "m" (state->LREG(3)));
asm("movl %0, f4":: "m" (state->LREG(4)));
asm("movl %0, f5":: "m" (state->LREG(5)));
asm("movl %0, f6":: "m" (state->LREG(6)));
asm("movl %0, f7":: "m" (state->LREG(7)));
}
int ieee_sig(int sig, int code, struct sigcontext *scp)
{
int ret;
vm_offset_t orig_pc;
state state;
get_fstate(&state);
state.scp = scp;
orig_pc = state.PC;
DP(1, "sig = 0x%x, code = 0x%x, pc = 0x%x, fsr = 0x%x\n", sig, code, state.PC, state.FSR);
ret = ieee_handle_exception(&state);
DP(1, " pc incremented by %d\n", state.PC - orig_pc);
set_fstate(&state);
return ret;
}
#endif /* KERNEL */
int ieee_handler_debug = 0;
#define COPYIN(U,K,N) ({if (copyin((AT)U, (AT)K, N) != 0) longjmp(copyin_buffer.copyfail, 1);0;})
/* Adressing modes. */
#define Adrmod_index_byte 0x1c
#define Adrmod_index_word 0x1d
#define Adrmod_index_doubleword 0x1e
#define Adrmod_index_quadword 0x1f
/* Is MODE an indexed addressing mode? */
#define Adrmod_is_index(mode) \
(mode == Adrmod_index_byte \
|| mode == Adrmod_index_word \
|| mode == Adrmod_index_doubleword \
|| mode == Adrmod_index_quadword)
/* Extract a bit field from a stream. Assume nbits less that
* or equal to 8. Also assume little endian. Assume no alignment
* restrictions on short.
*/
static inline int bit_extract(char *buffer, int offset, int nbits)
{
int start_byte = offset/8;
int end_byte = (offset + nbits - 1)/8;
return (((start_byte == end_byte? buffer[start_byte]:
*(short *)(buffer + start_byte)) >> offset%8)
& ((1 << nbits) - 1));
}
#ifdef DEBUG
static int invalid_float(union t_conv *p, int size)
{
int val;
if ( size == sizeof (float) )
val = (p->f_bits.exp == 0xff
|| (p->f_bits.exp == 0 && p->f_bits.mantissa != 0));
else if ( size == sizeof (double) )
val = (p->d_bits.exp == 0x7ff
|| (p->d_bits.exp == 0 && (p->d_bits.mantissa != 0 || p->d_bits.mantissa2 != 0)));
else
val = 1;
return (val);
}
static void print_op(struct operand *op)
{
if (op->type == op_type_float) {
if (invalid_float(&op->data, op->size)) {
if (op->size == sizeof(double)) {
printf("s: %d, e: %x, m1: %x, m2: %x", op->data.d_bits.sign, op->data.d_bits.exp, op->data.d_bits.mantissa, op->data.d_bits.mantissa2);
}
else {
printf("s: %d, e: %x, m1: %x", op->data.f_bits.sign, op->data.f_bits.exp, op->data.f_bits.mantissa);
}
}
else {
if (op->size == sizeof(double))
printf("%25.17e", op->data.d);
else
printf("%18.10e", op->data.f);
}
}
else
switch(op->size) {
case 1:
printf("%d", op->data.c);
break;
case 2:
printf("%d", op->data.s);
break;
case 4:
printf("%d", op->data.i);
break;
}
}
#endif
static const int regoffsets[] = {REGOFFSET(0), REGOFFSET(1), REGOFFSET(2),
REGOFFSET(3), REGOFFSET(4), REGOFFSET(5),
REGOFFSET(6), REGOFFSET(7)};
static inline void read_reg(int regno, struct operand *op, state *state) {
vm_offset_t addr = REGBASE(state) + regoffsets[regno];
switch(op->size) {
case 1: *(char *) &op->data = *(char *) addr; break;
case 2: *(short *) &op->data = *(short *) addr; break;
default: *(int *) &op->data = *(int *) addr; break;
}
op->where.tag = op_where_register;
op->where.addr = (vm_offset_t) &op->data;
}
static inline vm_offset_t reg_addr(int regno, state *state) {
return REGBASE(state) + regoffsets[regno];
}
static void read_freg(int regno, struct operand *op, state *state) {
vm_offset_t addr;
if (op->size == sizeof(float)) {
static const int offsets[] = {
FREGOFFSET(0), FREGOFFSET(1), FREGOFFSET(2), FREGOFFSET(3),
FREGOFFSET(4), FREGOFFSET(5), FREGOFFSET(6), FREGOFFSET(7)};
addr = FREGBASE(state) + offsets[regno];
*(float *) &op->data = *(float *) addr;
}
else {
static const int offsets[] = {
LREGOFFSET(0), LREGOFFSET(1), LREGOFFSET(2), LREGOFFSET(3),
LREGOFFSET(4), LREGOFFSET(5), LREGOFFSET(6), LREGOFFSET(7)};
addr = LREGBASE(state) + offsets[regno];
*(double *) &op->data = *(double *) addr;
}
op->where.tag = op_where_register;
op->where.addr = addr;
}
static int canonical_to_size(struct operand *op) {
int ret = FPC_TT_NONE;
union t_conv t = op->data;
if(op->type == op_type_float) {
if (op->size == sizeof(float)) {
unsigned long mantissa;
int exp = t.d_bits.exp + EXP_FBIAS - EXP_DBIAS;
op->data.f_bits.sign = t.d_bits.sign;
op->data.f_bits.exp = (exp < 0)? 0: ((exp > 0xff)? 0xff: exp);
if(exp >= 0xff && t.d_bits.exp < 0x7ff) {
/* Overflow. need +- infinity.
* Allow for trap on overflow.
*/
ret = FPC_TT_OVFL;
mantissa = 0;
}
else {
mantissa = t.d_bits.mantissa << 3;
mantissa |= (t.d_bits.mantissa2 >> 29) & 7;
if(exp <= 0 && (mantissa != 0 || t.d_bits.exp != 0)) {
/* Denormalize */
mantissa |= 0x800000;
mantissa >>= -exp;
ret = FPC_TT_UNDFL;
}
if (mantissa == 0 && ISNAN(t))
mantissa = 0x400000; /* Signaling NaN */
}
op->data.f_bits.mantissa = mantissa;
}
}
else {
switch (op->size) {
case sizeof(char):
op->data.c = t.i;
break;
case sizeof(short):
op->data.s = t.i;
break;
}
}
return ret;
}
static void canonicalise_op(struct operand *op) {
union t_conv t = op->data;
if(op->type == op_type_float) {
if (op->size == sizeof(float)) {
op->data.d_bits.sign = t.f_bits.sign;
op->data.d_bits.exp = (t.f_bits.exp == 0xff)? 0x7ff: t.f_bits.exp + EXP_DBIAS - EXP_FBIAS;
op->data.d_bits.mantissa = t.f_bits.mantissa >> 3;
op->data.d_bits.mantissa2 = (t.f_bits.mantissa & 7) << 29;
if (t.f_bits.exp == 0) {
if (t.f_bits.mantissa == 0) {
/* Float is zero */
op->data.d_bits.exp = 0;
}
else {
/* Was a subnormal float. Subnormal floats can always be converted
* to normal doubles.
*/
int norm;
op->data.d_bits.exp = 0;
norm = ieee_normalize(&(op->data));
op->data.d_bits.exp = EXP_DBIAS - EXP_FBIAS + norm;
}
}
}
}
else {
switch (op->size) {
case sizeof(char):
op->data.i = t.c;
break;
case sizeof(short):
op->data.i = t.s;
break;
}
}
}
#define MAX_LEN 21 /* The longest an instruction can be */
static struct {
vm_offset_t base;
char *max;
char buf[MAX_LEN];
#if defined(_KERNEL) && defined(__NetBSD__) && !defined(MACH)
label_t copyfail;
#else
jmp_buf copyfail;
#endif
} copyin_buffer;
static void store_result(struct operand *op)
{
if (op->where.tag == op_where_memory) {
/* copyout */
if (copyout((AT) &op->data, (AT)op->where.addr, op->size) != 0) {
longjmp (copyin_buffer.copyfail, 1);
}
}
else {
/* Register */
memcpy((char *)op->where.addr, (char *) &op->data, op->size);
}
}
#define FETCH_DATA(addr) ((addr) < copyin_buffer.max? 1: fetch_data(addr))
#define BUF_TO_UADDR(addr) ((addr) - copyin_buffer.buf + copyin_buffer.base)
#define FETCH_CHUNK 8 /* Size of chunks to copyin */
#define MAX(x,y) ((x) > (y)? (x): (y))
#define MIN(x,y) ((x) < (y)? (x): (y))
/* Fetch data from user space so as to validate buffer up to addr.
* We do some read ahead (to minimise the number of copyins) but
* we never read ahead past a page boundary incase that would not
* be mapped.
*/
static int fetch_data (char *addr) {
vm_offset_t u_addr = copyin_buffer.base + copyin_buffer.max - copyin_buffer.buf;
vm_offset_t u_end_addr = copyin_buffer.base + addr - copyin_buffer.buf;
vm_offset_t k_addr = (vm_offset_t) copyin_buffer.max;
int n;
int n_page = ns532_round_page(u_end_addr) - copyin_buffer.base + copyin_buffer.buf - copyin_buffer.max;
int n_max = MAX_LEN + copyin_buffer.buf - copyin_buffer.max;
int n_min = addr - copyin_buffer.max + 1;
n = MIN(n_max, MAX(n_min, MIN(FETCH_CHUNK, n_page)));
COPYIN(u_addr, k_addr, n);
DP(2, "fetch_data: addr = 0x%x, from 0x%x, to 0x%x, n = %d\n", addr, u_addr, k_addr, n);
copyin_buffer.max += n;
return 1;
}
static int get_displacement (char **buffer)
{
int disp;
char *buf = *buffer;
FETCH_DATA(buf);
switch (*buf & 0xc0)
{
case 0x00:
case 0x40:
disp = *buf++ & 0x7f;
disp = (disp & 0x40) ? disp | 0xffffff80: disp;
break;
case 0x80:
FETCH_DATA(buf + 1);
disp = *buf++ & 0x3f;
disp = (disp & 0x20) ? disp | 0xffffffc0: disp;
disp = (disp << 8) | (0xff & *buf++);
break;
case 0xc0:
FETCH_DATA(buf + 3);
disp = *buf++ & 0x3f;
disp = (disp & 0x20) ? disp | 0xffffffc0: disp;
disp = (disp << 8) | (0xff & *buf++);
disp = (disp << 8) | (0xff & *buf++);
disp = (disp << 8) | (0xff & *buf++);
break;
}
*buffer = buf;
DP(1, "disp = %d\n", disp);
return disp;
}
static int get_operand(char **buf, unsigned char gen, unsigned char index, struct operand *op, state *state)
{
int ret = FPC_TT_NONE;
vm_offset_t addr;
int disp1, disp2;
DP(1,"gen = 0x%x\n", gen);
if (op->type == op_type_float && (gen & ~7) == 0) {
read_freg(gen, op, state);
return ret;
}
switch (gen) {
case 0: case 1: case 2: case 3:
case 4: case 5: case 6: case 7:
if (op->class != op_class_addr) {
read_reg(gen, op, state);
return ret;
}
else
addr = reg_addr(gen, state);
break;
case 0x8: case 0x9: case 0xa: case 0xb:
case 0xc: case 0xd: case 0xe: case 0xf:
/* Register relative disp(R0 -- R7) */
/* rn out of state, then get data out of res_addr */
disp1 = get_displacement (buf);
addr = (disp1 + *(unsigned int *)reg_addr(gen & 7, state));
break;
case 0x10:
case 0x11:
case 0x12:
/* Memory relative disp2(disp1(FP, SP, SB)) */
disp1 = get_displacement (buf);
disp2 = get_displacement (buf);
addr = (disp1
+ (vm_offset_t) (gen == 0x10? state->FP: (gen == 0x11? state->SP:
state->SB)));
addr = disp2 + get_dword(addr);
break;
case 0x14:
/* Immediate */
if (op->class == op_class_read) {
char *p;
int i;
FETCH_DATA(*buf + op->size - 1);
for(p = (char *)&op->data, i = op->size; i--; p++) {
*p = *(*buf + i);
}
op->where.tag = op_where_immediate;
op->where.addr = 0;
*buf += op->size;
return ret;
}
else {
return FPC_TT_ILL;
}
case 0x15:
/* Absolute @disp */
disp1 = get_displacement (buf);
addr = disp1;
break;
case 0x16:
/* External EXT(disp1) + disp2 (Mod table stuff) */
disp1 = get_displacement (buf);
disp2 = get_displacement (buf);
return FPC_TT_ILL; /* Unsupported */
case 0x17:
/* Top of stack tos */
addr = state->SP;
switch (op->class) {
case op_class_read:
state->SP += op->size;
break;
case op_class_write:
state->SP -= op->size;
addr = state->SP;
break;
}
break;
case 0x18:
/* Memory space disp(FP) */
disp1 = get_displacement (buf);
addr = (disp1 + (vm_offset_t) state->FP);
break;
case 0x19:
/* Memory space disp(SP) */
disp1 = get_displacement (buf);
addr = (disp1 + (vm_offset_t) state->SP);
break;
case 0x1a:
/* Memory space disp(SB) */
disp1 = get_displacement (buf);
addr = (disp1 + (vm_offset_t) state->SB);
break;
case 0x1b:
/* Memory space disp(PC) */
disp1 = get_displacement (buf);
addr = disp1 + (vm_offset_t) state->PC;
break;
case 0x1c:
case 0x1d:
case 0x1e:
case 0x1f:
/* Scaled index basemode[R0 -- R7:B,W,D,Q] */
{
enum op_class save = op->class;
op->class = op_class_addr;
if ((ret = get_operand(buf, index >> 3, 0, op, state)) != FPC_TT_NONE)
return ret;
addr = op->where.addr + (* (int *) reg_addr(index & 7, state)) * (1 << (gen & 3));
op->class = save;
break;
}
}
if (op->class == op_class_read || op->class == op_class_rmw) {
COPYIN(addr, (vm_offset_t)&op->data, op->size);
}
op->where.tag = op_where_memory;
op->where.addr = addr;
return ret;
}
static int default_trap_handle(struct operand *op1, struct operand *op2, struct operand *f0_op, int xopcode, state *state)
{
int user_trap = FPC_TT_NONE;
unsigned int fsr = state->FSR;
int trap_type = fsr & FPC_TT;
DP(2, "trap type %d\n", trap_type);
{
int s = GET_SET_FSR(fsr & FPC_RM); /* Same rounding mode as at exception */
switch (trap_type)
{
case FPC_TT_UNDFL: /* Underflow */
user_trap = ieee_undfl(op1, op2, f0_op, xopcode, state);
break;
case FPC_TT_OVFL: /* Overflow */
user_trap = ieee_ovfl(op1, op2, f0_op, xopcode, state);
break;
case FPC_TT_DIV0: /* Divide by zero */
user_trap = ieee_dze(op1, op2, f0_op, xopcode, state);
break;
case FPC_TT_ILL: /* Illegal instruction */
/* Illegal instruction. Cause a SIGILL ? */
user_trap = FPC_TT_ILL;
break;
case FPC_TT_INVOP: /* Invalid operation */
user_trap = ieee_invop(op1, op2, f0_op, xopcode, state);
break;
case FPC_TT_INEXACT: /* Inexact result */
/* Nothing to be done */
/* Flags in hardware. We can't get here unless FPC_IEF is set */
user_trap = FPC_TT_INEXACT;
break;
case FPC_TT_NONE:
default:
DP(0,"ieee_handler: fpu trap type none\n");
}
SET_FSR(s);
}
return user_trap;
}
int ieee_handle_exception(state *state)
{
int fmt, xopcode, ret;
int fsr, user_trap = FPC_TT_NONE;
volatile int ofsr; /* Volatile for setjmp */
unsigned char int_type, float_type, opcode, gen1, gen2, index1, index2;
struct operand op1, op2, f0_op, *res;
char *buf = copyin_buffer.buf;
copyin_buffer.base = state->PC;
/* Save fsr and set fsr to 0 so that floating point operations within
* the emulation proceed in a known way. */
ofsr = GET_SET_FSR(0);
if (setjmp(copyin_buffer.copyfail) != 0) {
SET_FSR(ofsr);
return FPC_TT_ILL;
}
copyin_buffer.max = buf;
/* All fp instructions are 24 bits
* and extensions start after 3 bytes
*/
FETCH_DATA(buf + 2);
fsr = state->FSR;
switch(fmt = bit_extract(buf, 0, 8))
{
case 0x3e: /* Format 9 */
int_type = bit_extract(buf, 8, 2);
float_type = bit_extract(buf, 10, 1);
opcode = bit_extract(buf, 11, 3);
fmt = fmt9;
break;
case 0xbe: /* Format 11 */
case 0xfe: /* Format 12 */
fmt = (fmt == 0xbe)? fmt11: fmt12;
float_type = bit_extract(buf, 8, 1);
opcode = bit_extract(buf, 10, 4);
break;
default:
user_trap = FPC_TT_ILL;
DP(0, "ieee_handler: format not of a floating point instruction\n");
}
xopcode = XOPCODE(fmt, opcode);
DP(2, "xopcode: 0x%x\n", xopcode);
gen2 = bit_extract(buf, 14, 5);
gen1 = bit_extract(buf, 19, 5);
buf += 3;
if (Adrmod_is_index(gen1)) {
FETCH_DATA(buf);
index1 = *buf++;
}
if (Adrmod_is_index(gen2)) {
FETCH_DATA(buf);
index2 = *buf++;
}
op1.class = op_class_read;
op2.class = op_class_rmw;
op1.type = op2.type = op_type_float;
op1.size = op2.size = float_type? 4: 8;
res = &op2;
switch(xopcode) {
case MOVLF:
op1.type = op_type_float; op1.size = 8;
op2.size = 4; op2.class = op_class_write;
break;
case MOVFL:
op1.type = op_type_float; op1.size = 4;
op2.size = 8; op2.class = op_class_write;
break;
case MOVIF:
op1.type = op_type_int; op1.size = 1 << int_type;
op2.class = op_class_write;
break;
case NEGF:
op2.class = op_class_write;
break;
case ROUNDFI:
case TRUNCFI:
case FLOORFI:
op2.type = op_type_int; op2.size = 1 << int_type;
break;
case CMPF:
op2.class = op_class_read;
res = 0;
break;
case POLYF:
case DOTF:
op1.type = op2.type = f0_op.type = op_type_float;
op1.size = op2.size = f0_op.size = float_type? 4: 8;
op2.class = op_class_read;
f0_op.class = op_class_rmw;
read_freg(0, &f0_op, state);
canonicalise_op(&f0_op);
res = &f0_op;
break;
}
if ((ret = get_operand(&buf, gen1, index1, &op1, state)) != FPC_TT_NONE) {
user_trap = ret;
DP(0, "get_operand failed\n");
}
if ((ret = get_operand(&buf, gen2, index2, &op2, state)) != FPC_TT_NONE) {
user_trap = ret;
DP(0, "get_operand failed\n");
}
#ifdef DEBUG
if (ieee_handler_debug > 1) {
printf( "op1 = "); print_op(&op1); printf("\n");
printf( "op2 = "); print_op(&op2); printf("\n");
}
#endif
canonicalise_op(&op1);
canonicalise_op(&op2);
if(user_trap == FPC_TT_NONE) {
user_trap = default_trap_handle(&op1, &op2, &f0_op, xopcode, state);
fsr = state->FSR; /* May have been side effected */
/* user_trap now has traps generated during emulation. Correct ieee
* results already calculated, but must see whether we need to
* pass trap on to user.
*
* User trap can be set for many reasons. eg dividing a denorm by 0
* might initially result in an invalid operand trap, but during
* emulation we set the divide by zero trap.
*/
if (res) {
int ret;
if((ret = canonical_to_size(res)) != FPC_TT_NONE)
user_trap = ret;
}
switch (user_trap) {
case FPC_TT_UNDFL:
fsr |= FPC_UF;
if ((fsr & FPC_UNDE) == 0)
user_trap = FPC_TT_NONE;
break;
case FPC_TT_OVFL:
fsr |= FPC_OVF;
if ((fsr & FPC_OVE) == 0)
user_trap = FPC_TT_NONE;
break;
case FPC_TT_DIV0:
fsr |= FPC_DZF;
if ((fsr & FPC_DZE) == 0)
user_trap = FPC_TT_NONE;
break;
case FPC_TT_ILL:
break;
case FPC_TT_INVOP:
fsr |= FPC_IVF;
if ((fsr & FPC_IVE) == 0)
user_trap = FPC_TT_NONE;
break;
case FPC_TT_INEXACT:
fsr |= FPC_IF;
if ((fsr & FPC_IEN) == 0)
user_trap = FPC_TT_NONE;
break;
}
}
if(user_trap == FPC_TT_NONE) {
if(res) {
#ifdef DEBUG
if (ieee_handler_debug > 1) {
printf( "res = "); print_op(res); printf("\n");
}
#endif
store_result(res);
}
}
state->PC = BUF_TO_UADDR(buf);
SET_FSR(ofsr);
state->FSR = fsr;
return user_trap;
}
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