768 lines
21 KiB
C
768 lines
21 KiB
C
/* $NetBSD: ieee_handler.c,v 1.4 1996/10/13 03:30:25 christos Exp $ */
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/*
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* IEEE floating point support for NS32081 and NS32381 fpus.
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* Copyright (c) 1995 Ian Dall
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* All Rights Reserved.
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*
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* Permission to use, copy, modify and distribute this software and its
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* documentation is hereby granted, provided that both the copyright
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* notice and this permission notice appear in all copies of the
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* software, derivative works or modified versions, and any portions
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* thereof, and that both notices appear in supporting documentation.
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*
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* IAN DALL ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" CONDITION.
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* IAN DALL DISCLAIMS ANY LIABILITY OF ANY KIND FOR ANY DAMAGES
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* WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
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*/
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/*
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* File: ieee_handler.c
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* Author: Ian Dall
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* Date: November 1995
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*
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* Entry points for the ieee exception handling package.
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* decodes floating point instructions.
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*
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* HISTORY
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* 23-Apr-96 Ian Dall (Ian.Dall@dsto.defence.gov.au)
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* Advance pc past trapping instruction always.
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*
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* 13-Apr-96 Matthias Pfaller <leo@dachau.marco.de>
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* Fix up test for denormalized result in canonical_to_size().
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*
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* 13-Apr-96 Ian Dall (Ian.Dall@dsto.defence.gov.au)
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* Clean up types in get_operand().
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*
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* 13-Apr-96 Matthias Pfaller <leo@dachau.marco.de>
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* Remove redundant status test code from fetch_data(). Fix
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* register relative and PC relative address decoding.
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*
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* 02-Apr-96 Ian Dall (Ian.Dall@dsto.defence.gov.au)
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* Make zero floats get canonicalized to doubles properly.
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*
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* 02-Apr-96 Ian Dall (Ian.Dall@dsto.defence.gov.au)
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* Notice that default_trap_handle() has a side effect of changing
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* state->FSR.
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*
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* 02-Apr-96 Matthias Pfaller <leo@dachau.marco.de>
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* Add NetBSD kernel support.
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*
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* 14-Dec-95 Ian Dall (Ian.Dall@dsto.defence.gov.au)
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* First release.
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* */
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#include <sys/types.h>
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#include <stddef.h>
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#include "ieee_internal.h"
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#if defined(KERNEL) || defined(_KERNEL)
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# ifdef MACH
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# include <setjmp.h>
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# define setjmp _setjmp
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# define longjmp _longjmp
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# define AT vm_offset_t
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# elif defined(__NetBSD__) /* MACH */
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# include <machine/param.h>
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# include <sys/systm.h>
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# define longjmp(x, y) longjmp(&x)
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# define setjmp(x) setjmp(&x)
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# define AT void *
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# endif
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# define get_dword(addr) ({long _t; COPYIN((addr), (vm_offset_t) &_t, sizeof(long)); _t;})
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#else /* KERNEL */
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# include <machine/param.h>
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# include <setjmp.h>
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# define AT vm_offset_t
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# ifdef DEBUG
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# include <stdio.h>
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# endif
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# define copyin(u,k,n) ({vm_offset_t _u = (u), _k = (k); memcpy((char *) _k, (char *) _u,n);0;})
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# define copyout(k,u,n) ({vm_offset_t _u = (u), _k = (k); memcpy((char *) _u, (char *) _k,n);0;})
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# define get_dword(addr) (* (unsigned int *) addr)
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# define ns532_round_page(addr) (((addr) + NBPG - 1) & ~(NBPG - 1))
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static void get_fstate(state *state) {
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asm("sfsr %0" : "=g" (state->FSR));
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asm("movl f0, %0" : "=m" (state->LREG(0)));
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asm("movl f1, %0" : "=m" (state->LREG(1)));
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asm("movl f2, %0" : "=m" (state->LREG(2)));
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asm("movl f3, %0" : "=m" (state->LREG(3)));
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asm("movl f4, %0" : "=m" (state->LREG(4)));
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asm("movl f5, %0" : "=m" (state->LREG(5)));
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asm("movl f6, %0" : "=m" (state->LREG(6)));
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asm("movl f7, %0" : "=m" (state->LREG(7)));
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}
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static void set_fstate(state *state) {
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/* DON'T tell gcc we are clobbering fp registers, else it will
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* save and restore some, undoing our changes!
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*/
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asm("lfsr %0":: "g" (state->FSR));
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asm("movl %0, f0":: "m" (state->LREG(0)));
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asm("movl %0, f1":: "m" (state->LREG(1)));
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asm("movl %0, f2":: "m" (state->LREG(2)));
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asm("movl %0, f3":: "m" (state->LREG(3)));
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asm("movl %0, f4":: "m" (state->LREG(4)));
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asm("movl %0, f5":: "m" (state->LREG(5)));
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asm("movl %0, f6":: "m" (state->LREG(6)));
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asm("movl %0, f7":: "m" (state->LREG(7)));
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}
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int ieee_sig(int sig, int code, struct sigcontext *scp)
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{
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int ret;
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vm_offset_t orig_pc;
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state state;
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get_fstate(&state);
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state.scp = scp;
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orig_pc = state.PC;
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DP(1, "sig = 0x%x, code = 0x%x, pc = 0x%x, fsr = 0x%x\n", sig, code, state.PC, state.FSR);
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ret = ieee_handle_exception(&state);
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DP(1, " pc incremented by %d\n", state.PC - orig_pc);
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set_fstate(&state);
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return ret;
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}
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#endif /* KERNEL */
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int ieee_handler_debug = 0;
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#define COPYIN(U,K,N) ({if (copyin((AT)U, (AT)K, N) != 0) longjmp(copyin_buffer.copyfail, 1);0;})
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/* Adressing modes. */
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#define Adrmod_index_byte 0x1c
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#define Adrmod_index_word 0x1d
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#define Adrmod_index_doubleword 0x1e
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#define Adrmod_index_quadword 0x1f
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/* Is MODE an indexed addressing mode? */
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#define Adrmod_is_index(mode) \
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(mode == Adrmod_index_byte \
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|| mode == Adrmod_index_word \
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|| mode == Adrmod_index_doubleword \
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|| mode == Adrmod_index_quadword)
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/* Extract a bit field from a stream. Assume nbits less that
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* or equal to 8. Also assume little endian. Assume no alignment
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* restrictions on short.
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*/
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static inline int bit_extract(char *buffer, int offset, int nbits)
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{
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int start_byte = offset/8;
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int end_byte = (offset + nbits - 1)/8;
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return (((start_byte == end_byte? buffer[start_byte]:
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*(short *)(buffer + start_byte)) >> offset%8)
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& ((1 << nbits) - 1));
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}
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#ifdef DEBUG
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static int invalid_float(union t_conv *p, int size)
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{
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int val;
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if ( size == sizeof (float) )
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val = (p->f_bits.exp == 0xff
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|| (p->f_bits.exp == 0 && p->f_bits.mantissa != 0));
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else if ( size == sizeof (double) )
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val = (p->d_bits.exp == 0x7ff
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|| (p->d_bits.exp == 0 && (p->d_bits.mantissa != 0 || p->d_bits.mantissa2 != 0)));
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else
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val = 1;
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return (val);
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}
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static void print_op(struct operand *op)
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{
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if (op->type == op_type_float) {
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if (invalid_float(&op->data, op->size)) {
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if (op->size == sizeof(double)) {
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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);
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}
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else {
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printf("s: %d, e: %x, m1: %x", op->data.f_bits.sign, op->data.f_bits.exp, op->data.f_bits.mantissa);
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}
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}
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else {
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if (op->size == sizeof(double))
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printf("%25.17e", op->data.d);
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else
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printf("%18.10e", op->data.f);
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}
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}
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else
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switch(op->size) {
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case 1:
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printf("%d", op->data.c);
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break;
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case 2:
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printf("%d", op->data.s);
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break;
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case 4:
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printf("%d", op->data.i);
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break;
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}
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}
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#endif
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static const int regoffsets[] = {REGOFFSET(0), REGOFFSET(1), REGOFFSET(2),
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REGOFFSET(3), REGOFFSET(4), REGOFFSET(5),
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REGOFFSET(6), REGOFFSET(7)};
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static inline void read_reg(int regno, struct operand *op, state *state) {
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vm_offset_t addr = REGBASE(state) + regoffsets[regno];
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switch(op->size) {
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case 1: *(char *) &op->data = *(char *) addr; break;
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case 2: *(short *) &op->data = *(short *) addr; break;
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default: *(int *) &op->data = *(int *) addr; break;
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}
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op->where.tag = op_where_register;
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op->where.addr = (vm_offset_t) &op->data;
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}
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static inline vm_offset_t reg_addr(int regno, state *state) {
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return REGBASE(state) + regoffsets[regno];
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}
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static void read_freg(int regno, struct operand *op, state *state) {
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vm_offset_t addr;
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if (op->size == sizeof(float)) {
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static const int offsets[] = {
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FREGOFFSET(0), FREGOFFSET(1), FREGOFFSET(2), FREGOFFSET(3),
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FREGOFFSET(4), FREGOFFSET(5), FREGOFFSET(6), FREGOFFSET(7)};
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addr = FREGBASE(state) + offsets[regno];
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*(float *) &op->data = *(float *) addr;
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}
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else {
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static const int offsets[] = {
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LREGOFFSET(0), LREGOFFSET(1), LREGOFFSET(2), LREGOFFSET(3),
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LREGOFFSET(4), LREGOFFSET(5), LREGOFFSET(6), LREGOFFSET(7)};
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addr = LREGBASE(state) + offsets[regno];
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*(double *) &op->data = *(double *) addr;
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}
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op->where.tag = op_where_register;
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op->where.addr = addr;
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}
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static int canonical_to_size(struct operand *op) {
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int ret = FPC_TT_NONE;
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union t_conv t = op->data;
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if(op->type == op_type_float) {
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if (op->size == sizeof(float)) {
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unsigned long mantissa;
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int exp = t.d_bits.exp + EXP_FBIAS - EXP_DBIAS;
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op->data.f_bits.sign = t.d_bits.sign;
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op->data.f_bits.exp = (exp < 0)? 0: ((exp > 0xff)? 0xff: exp);
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if(exp >= 0xff && t.d_bits.exp < 0x7ff) {
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/* Overflow. need +- infinity.
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* Allow for trap on overflow.
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*/
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ret = FPC_TT_OVFL;
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mantissa = 0;
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}
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else {
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mantissa = t.d_bits.mantissa << 3;
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mantissa |= (t.d_bits.mantissa2 >> 29) & 7;
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if(exp <= 0 && (mantissa != 0 || t.d_bits.exp != 0)) {
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/* Denormalize */
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mantissa |= 0x800000;
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mantissa >>= -exp;
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ret = FPC_TT_UNDFL;
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}
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if (mantissa == 0 && ISNAN(t))
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mantissa = 0x400000; /* Signaling NaN */
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}
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op->data.f_bits.mantissa = mantissa;
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}
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}
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else {
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switch (op->size) {
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case sizeof(char):
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op->data.c = t.i;
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break;
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case sizeof(short):
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op->data.s = t.i;
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break;
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}
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}
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return ret;
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}
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static void canonicalise_op(struct operand *op) {
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union t_conv t = op->data;
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if(op->type == op_type_float) {
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if (op->size == sizeof(float)) {
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op->data.d_bits.sign = t.f_bits.sign;
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op->data.d_bits.exp = (t.f_bits.exp == 0xff)? 0x7ff: t.f_bits.exp + EXP_DBIAS - EXP_FBIAS;
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op->data.d_bits.mantissa = t.f_bits.mantissa >> 3;
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op->data.d_bits.mantissa2 = (t.f_bits.mantissa & 7) << 29;
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if (t.f_bits.exp == 0) {
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if (t.f_bits.mantissa == 0) {
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/* Float is zero */
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op->data.d_bits.exp = 0;
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}
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else {
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/* Was a subnormal float. Subnormal floats can always be converted
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* to normal doubles.
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*/
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int norm;
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op->data.d_bits.exp = 0;
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norm = ieee_normalize(&(op->data));
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op->data.d_bits.exp = EXP_DBIAS - EXP_FBIAS + norm;
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}
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}
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}
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}
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else {
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switch (op->size) {
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case sizeof(char):
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op->data.i = t.c;
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break;
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case sizeof(short):
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op->data.i = t.s;
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break;
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}
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}
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}
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#define MAX_LEN 21 /* The longest an instruction can be */
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static struct {
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vm_offset_t base;
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char *max;
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char buf[MAX_LEN];
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#if defined(_KERNEL) && defined(__NetBSD__) && !defined(MACH)
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label_t copyfail;
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#else
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jmp_buf copyfail;
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#endif
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} copyin_buffer;
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static void store_result(struct operand *op)
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{
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if (op->where.tag == op_where_memory) {
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/* copyout */
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if (copyout((AT) &op->data, (AT)op->where.addr, op->size) != 0) {
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longjmp (copyin_buffer.copyfail, 1);
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}
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}
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else {
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/* Register */
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memcpy((char *)op->where.addr, (char *) &op->data, op->size);
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}
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}
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#define FETCH_DATA(addr) ((addr) < copyin_buffer.max? 1: fetch_data(addr))
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#define BUF_TO_UADDR(addr) ((addr) - copyin_buffer.buf + copyin_buffer.base)
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#define FETCH_CHUNK 8 /* Size of chunks to copyin */
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#define MAX(x,y) ((x) > (y)? (x): (y))
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#define MIN(x,y) ((x) < (y)? (x): (y))
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/* Fetch data from user space so as to validate buffer up to addr.
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* We do some read ahead (to minimise the number of copyins) but
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* we never read ahead past a page boundary incase that would not
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* be mapped.
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*/
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static int fetch_data (char *addr) {
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vm_offset_t u_addr = copyin_buffer.base + copyin_buffer.max - copyin_buffer.buf;
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vm_offset_t u_end_addr = copyin_buffer.base + addr - copyin_buffer.buf;
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vm_offset_t k_addr = (vm_offset_t) copyin_buffer.max;
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int n;
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int n_page = ns532_round_page(u_end_addr) - copyin_buffer.base + copyin_buffer.buf - copyin_buffer.max;
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int n_max = MAX_LEN + copyin_buffer.buf - copyin_buffer.max;
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int n_min = addr - copyin_buffer.max + 1;
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n = MIN(n_max, MAX(n_min, MIN(FETCH_CHUNK, n_page)));
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COPYIN(u_addr, k_addr, n);
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DP(2, "fetch_data: addr = 0x%x, from 0x%x, to 0x%x, n = %d\n", addr, u_addr, k_addr, n);
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copyin_buffer.max += n;
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return 1;
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}
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static int get_displacement (char **buffer)
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{
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int disp;
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char *buf = *buffer;
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FETCH_DATA(buf);
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switch (*buf & 0xc0)
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{
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case 0x00:
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case 0x40:
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disp = *buf++ & 0x7f;
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disp = (disp & 0x40) ? disp | 0xffffff80: disp;
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break;
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case 0x80:
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FETCH_DATA(buf + 1);
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disp = *buf++ & 0x3f;
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disp = (disp & 0x20) ? disp | 0xffffffc0: disp;
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disp = (disp << 8) | (0xff & *buf++);
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break;
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case 0xc0:
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FETCH_DATA(buf + 3);
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disp = *buf++ & 0x3f;
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disp = (disp & 0x20) ? disp | 0xffffffc0: disp;
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disp = (disp << 8) | (0xff & *buf++);
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disp = (disp << 8) | (0xff & *buf++);
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disp = (disp << 8) | (0xff & *buf++);
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break;
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}
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*buffer = buf;
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DP(1, "disp = %d\n", disp);
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return disp;
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}
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static int get_operand(char **buf, unsigned char gen, unsigned char index, struct operand *op, state *state)
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{
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int ret = FPC_TT_NONE;
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vm_offset_t addr;
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int disp1, disp2;
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DP(1,"gen = 0x%x\n", gen);
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if (op->type == op_type_float && (gen & ~7) == 0) {
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read_freg(gen, op, state);
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return ret;
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}
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switch (gen) {
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case 0: case 1: case 2: case 3:
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case 4: case 5: case 6: case 7:
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if (op->class != op_class_addr) {
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read_reg(gen, op, state);
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return ret;
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}
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else
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addr = reg_addr(gen, state);
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break;
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case 0x8: case 0x9: case 0xa: case 0xb:
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case 0xc: case 0xd: case 0xe: case 0xf:
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/* Register relative disp(R0 -- R7) */
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/* rn out of state, then get data out of res_addr */
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disp1 = get_displacement (buf);
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addr = (disp1 + *(unsigned int *)reg_addr(gen & 7, state));
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break;
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case 0x10:
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case 0x11:
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case 0x12:
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/* Memory relative disp2(disp1(FP, SP, SB)) */
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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;
|
|
}
|