linux-user/sparc/cpu_loop.c - third_party/qemu - Git at Google

 /*
  *  qemu user cpu loop
  *
  *  Copyright (c) 2003-2008 Fabrice Bellard
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
  *  the Free Software Foundation; either version 2 of the License, or
  *  (at your option) any later version.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  */

 #include "qemu/osdep.h"
 #include "qemu-common.h"
 #include "qemu.h"
 #include "cpu_loop-common.h"

 #define SPARC64_STACK_BIAS 2047

 //#define DEBUG_WIN

 /* WARNING: dealing with register windows _is_ complicated. More info
    can be found at http://www.sics.se/~psm/sparcstack.html */
 static inline int get_reg_index(CPUSPARCState *env, int cwp, int index)
 {
     index = (index + cwp * 16) % (16 * env->nwindows);
     /* wrap handling : if cwp is on the last window, then we use the
        registers 'after' the end */
     if (index < 8 && env->cwp == env->nwindows - 1)
         index += 16 * env->nwindows;
     return index;
 }

 /* save the register window 'cwp1' */
 static inline void save_window_offset(CPUSPARCState *env, int cwp1)
 {
     unsigned int i;
     abi_ulong sp_ptr;

     sp_ptr = env->regbase[get_reg_index(env, cwp1, 6)];
 #ifdef TARGET_SPARC64
     if (sp_ptr & 3)
         sp_ptr += SPARC64_STACK_BIAS;
 #endif
 #if defined(DEBUG_WIN)
     printf("win_overflow: sp_ptr=0x" TARGET_ABI_FMT_lx " save_cwp=%d\n",
            sp_ptr, cwp1);
 #endif
     for(i = 0; i < 16; i++) {
         /* FIXME - what to do if put_user() fails? */
         put_user_ual(env->regbase[get_reg_index(env, cwp1, 8 + i)], sp_ptr);
         sp_ptr += sizeof(abi_ulong);
     }
 }

 static void save_window(CPUSPARCState *env)
 {
 #ifndef TARGET_SPARC64
     unsigned int new_wim;
     new_wim = ((env->wim >> 1) | (env->wim << (env->nwindows - 1))) &
         ((1LL << env->nwindows) - 1);
     save_window_offset(env, cpu_cwp_dec(env, env->cwp - 2));
     env->wim = new_wim;
 #else
     save_window_offset(env, cpu_cwp_dec(env, env->cwp - 2));
     env->cansave++;
     env->canrestore--;
 #endif
 }

 static void restore_window(CPUSPARCState *env)
 {
 #ifndef TARGET_SPARC64
     unsigned int new_wim;
 #endif
     unsigned int i, cwp1;
     abi_ulong sp_ptr;

 #ifndef TARGET_SPARC64
     new_wim = ((env->wim << 1) | (env->wim >> (env->nwindows - 1))) &
         ((1LL << env->nwindows) - 1);
 #endif

     /* restore the invalid window */
     cwp1 = cpu_cwp_inc(env, env->cwp + 1);
     sp_ptr = env->regbase[get_reg_index(env, cwp1, 6)];
 #ifdef TARGET_SPARC64
     if (sp_ptr & 3)
         sp_ptr += SPARC64_STACK_BIAS;
 #endif
 #if defined(DEBUG_WIN)
     printf("win_underflow: sp_ptr=0x" TARGET_ABI_FMT_lx " load_cwp=%d\n",
            sp_ptr, cwp1);
 #endif
     for(i = 0; i < 16; i++) {
         /* FIXME - what to do if get_user() fails? */
         get_user_ual(env->regbase[get_reg_index(env, cwp1, 8 + i)], sp_ptr);
         sp_ptr += sizeof(abi_ulong);
     }
 #ifdef TARGET_SPARC64
     env->canrestore++;
     if (env->cleanwin < env->nwindows - 1)
         env->cleanwin++;
     env->cansave--;
 #else
     env->wim = new_wim;
 #endif
 }

 static void flush_windows(CPUSPARCState *env)
 {
     int offset, cwp1;

     offset = 1;
     for(;;) {
         /* if restore would invoke restore_window(), then we can stop */
         cwp1 = cpu_cwp_inc(env, env->cwp + offset);
 #ifndef TARGET_SPARC64
         if (env->wim & (1 << cwp1))
             break;
 #else
         if (env->canrestore == 0)
             break;
         env->cansave++;
         env->canrestore--;
 #endif
         save_window_offset(env, cwp1);
         offset++;
     }
     cwp1 = cpu_cwp_inc(env, env->cwp + 1);
 #ifndef TARGET_SPARC64
     /* set wim so that restore will reload the registers */
     env->wim = 1 << cwp1;
 #endif
 #if defined(DEBUG_WIN)
     printf("flush_windows: nb=%d\n", offset - 1);
 #endif
 }

 void cpu_loop (CPUSPARCState *env)
 {
     CPUState *cs = env_cpu(env);
     int trapnr;
     abi_long ret;
     target_siginfo_t info;

     while (1) {
         cpu_exec_start(cs);
         trapnr = cpu_exec(cs);
         cpu_exec_end(cs);
         process_queued_cpu_work(cs);

         /* Compute PSR before exposing state.  */
         if (env->cc_op != CC_OP_FLAGS) {
             cpu_get_psr(env);
         }

         switch (trapnr) {
 #ifndef TARGET_SPARC64
         case 0x88:
         case 0x90:
 #else
         case 0x110:
         case 0x16d:
 #endif
             ret = do_syscall (env, env->gregs[1],
                               env->regwptr[0], env->regwptr[1],
                               env->regwptr[2], env->regwptr[3],
                               env->regwptr[4], env->regwptr[5],
                               0, 0);
             if (ret == -TARGET_ERESTARTSYS || ret == -TARGET_QEMU_ESIGRETURN) {
                 break;
             }
             if ((abi_ulong)ret >= (abi_ulong)(-515)) {
 #if defined(TARGET_SPARC64) && !defined(TARGET_ABI32)
                 env->xcc |= PSR_CARRY;
 #else
                 env->psr |= PSR_CARRY;
 #endif
                 ret = -ret;
             } else {
 #if defined(TARGET_SPARC64) && !defined(TARGET_ABI32)
                 env->xcc &= ~PSR_CARRY;
 #else
                 env->psr &= ~PSR_CARRY;
 #endif
             }
             env->regwptr[0] = ret;
             /* next instruction */
             env->pc = env->npc;
             env->npc = env->npc + 4;
             break;
         case 0x83: /* flush windows */
 #ifdef TARGET_ABI32
         case 0x103:
 #endif
             flush_windows(env);
             /* next instruction */
             env->pc = env->npc;
             env->npc = env->npc + 4;
             break;
 #ifndef TARGET_SPARC64
         case TT_WIN_OVF: /* window overflow */
             save_window(env);
             break;
         case TT_WIN_UNF: /* window underflow */
             restore_window(env);
             break;
         case TT_TFAULT:
         case TT_DFAULT:
             {
                 info.si_signo = TARGET_SIGSEGV;
                 info.si_errno = 0;
                 /* XXX: check env->error_code */
                 info.si_code = TARGET_SEGV_MAPERR;
                 info._sifields._sigfault._addr = env->mmuregs[4];
                 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
             }
             break;
 #else
         case TT_SPILL: /* window overflow */
             save_window(env);
             break;
         case TT_FILL: /* window underflow */
             restore_window(env);
             break;
         case TT_TFAULT:
         case TT_DFAULT:
             {
                 info.si_signo = TARGET_SIGSEGV;
                 info.si_errno = 0;
                 /* XXX: check env->error_code */
                 info.si_code = TARGET_SEGV_MAPERR;
                 if (trapnr == TT_DFAULT)
                     info._sifields._sigfault._addr = env->dmmu.mmuregs[4];
                 else
                     info._sifields._sigfault._addr = cpu_tsptr(env)->tpc;
                 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
             }
             break;
 #ifndef TARGET_ABI32
         case 0x16e:
             flush_windows(env);
             sparc64_get_context(env);
             break;
         case 0x16f:
             flush_windows(env);
             sparc64_set_context(env);
             break;
 #endif
 #endif
         case EXCP_INTERRUPT:
             /* just indicate that signals should be handled asap */
             break;
         case TT_ILL_INSN:
             {
                 info.si_signo = TARGET_SIGILL;
                 info.si_errno = 0;
                 info.si_code = TARGET_ILL_ILLOPC;
                 info._sifields._sigfault._addr = env->pc;
                 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
             }
             break;
         case EXCP_DEBUG:
             info.si_signo = TARGET_SIGTRAP;
             info.si_errno = 0;
             info.si_code = TARGET_TRAP_BRKPT;
             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
             break;
         case EXCP_ATOMIC:
             cpu_exec_step_atomic(cs);
             break;
         default:
             fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr);
             cpu_dump_state(cs, stderr, 0);
             exit(EXIT_FAILURE);
         }
         process_pending_signals (env);
     }
 }

 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
 {
     int i;
     env->pc = regs->pc;
     env->npc = regs->npc;
     env->y = regs->y;
     for(i = 0; i < 8; i++)
         env->gregs[i] = regs->u_regs[i];
     for(i = 0; i < 8; i++)
         env->regwptr[i] = regs->u_regs[i + 8];
 }
	/*
	* qemu user cpu loop
	*
	* Copyright (c) 2003-2008 Fabrice Bellard
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, see <http://www.gnu.org/licenses/>.
	*/

	#include "qemu/osdep.h"
	#include "qemu-common.h"
	#include "qemu.h"
	#include "cpu_loop-common.h"

	#define SPARC64_STACK_BIAS 2047

	//#define DEBUG_WIN

	/* WARNING: dealing with register windows _is_ complicated. More info
	can be found at http://www.sics.se/~psm/sparcstack.html */
	static inline int get_reg_index(CPUSPARCState *env, int cwp, int index)
	{
	index = (index + cwp * 16) % (16 * env->nwindows);
	/* wrap handling : if cwp is on the last window, then we use the
	registers 'after' the end */
	if (index < 8 && env->cwp == env->nwindows - 1)
	index += 16 * env->nwindows;
	return index;
	}

	/* save the register window 'cwp1' */
	static inline void save_window_offset(CPUSPARCState *env, int cwp1)
	{
	unsigned int i;
	abi_ulong sp_ptr;

	sp_ptr = env->regbase[get_reg_index(env, cwp1, 6)];
	#ifdef TARGET_SPARC64
	if (sp_ptr & 3)
	sp_ptr += SPARC64_STACK_BIAS;
	#endif
	#if defined(DEBUG_WIN)
	printf("win_overflow: sp_ptr=0x" TARGET_ABI_FMT_lx " save_cwp=%d\n",
	sp_ptr, cwp1);
	#endif
	for(i = 0; i < 16; i++) {
	/* FIXME - what to do if put_user() fails? */
	put_user_ual(env->regbase[get_reg_index(env, cwp1, 8 + i)], sp_ptr);
	sp_ptr += sizeof(abi_ulong);
	}
	}

	static void save_window(CPUSPARCState *env)
	{
	#ifndef TARGET_SPARC64
	unsigned int new_wim;
	new_wim = ((env->wim >> 1) \| (env->wim << (env->nwindows - 1))) &
	((1LL << env->nwindows) - 1);
	save_window_offset(env, cpu_cwp_dec(env, env->cwp - 2));
	env->wim = new_wim;
	#else
	save_window_offset(env, cpu_cwp_dec(env, env->cwp - 2));
	env->cansave++;
	env->canrestore--;
	#endif
	}

	static void restore_window(CPUSPARCState *env)
	{
	#ifndef TARGET_SPARC64
	unsigned int new_wim;
	#endif
	unsigned int i, cwp1;
	abi_ulong sp_ptr;

	#ifndef TARGET_SPARC64
	new_wim = ((env->wim << 1) \| (env->wim >> (env->nwindows - 1))) &
	((1LL << env->nwindows) - 1);
	#endif

	/* restore the invalid window */
	cwp1 = cpu_cwp_inc(env, env->cwp + 1);
	sp_ptr = env->regbase[get_reg_index(env, cwp1, 6)];
	#ifdef TARGET_SPARC64
	if (sp_ptr & 3)
	sp_ptr += SPARC64_STACK_BIAS;
	#endif
	#if defined(DEBUG_WIN)
	printf("win_underflow: sp_ptr=0x" TARGET_ABI_FMT_lx " load_cwp=%d\n",
	sp_ptr, cwp1);
	#endif
	for(i = 0; i < 16; i++) {
	/* FIXME - what to do if get_user() fails? */
	get_user_ual(env->regbase[get_reg_index(env, cwp1, 8 + i)], sp_ptr);
	sp_ptr += sizeof(abi_ulong);
	}
	#ifdef TARGET_SPARC64
	env->canrestore++;
	if (env->cleanwin < env->nwindows - 1)
	env->cleanwin++;
	env->cansave--;
	#else
	env->wim = new_wim;
	#endif
	}

	static void flush_windows(CPUSPARCState *env)
	{
	int offset, cwp1;

	offset = 1;
	for(;;) {
	/* if restore would invoke restore_window(), then we can stop */
	cwp1 = cpu_cwp_inc(env, env->cwp + offset);
	#ifndef TARGET_SPARC64
	if (env->wim & (1 << cwp1))
	break;
	#else
	if (env->canrestore == 0)
	break;
	env->cansave++;
	env->canrestore--;
	#endif
	save_window_offset(env, cwp1);
	offset++;
	}
	cwp1 = cpu_cwp_inc(env, env->cwp + 1);
	#ifndef TARGET_SPARC64
	/* set wim so that restore will reload the registers */
	env->wim = 1 << cwp1;
	#endif
	#if defined(DEBUG_WIN)
	printf("flush_windows: nb=%d\n", offset - 1);
	#endif
	}

	void cpu_loop (CPUSPARCState *env)
	{
	CPUState *cs = env_cpu(env);
	int trapnr;
	abi_long ret;
	target_siginfo_t info;

	while (1) {
	cpu_exec_start(cs);
	trapnr = cpu_exec(cs);
	cpu_exec_end(cs);
	process_queued_cpu_work(cs);

	/* Compute PSR before exposing state. */
	if (env->cc_op != CC_OP_FLAGS) {
	cpu_get_psr(env);
	}

	switch (trapnr) {
	#ifndef TARGET_SPARC64
	case 0x88:
	case 0x90:
	#else
	case 0x110:
	case 0x16d:
	#endif
	ret = do_syscall (env, env->gregs[1],
	env->regwptr[0], env->regwptr[1],
	env->regwptr[2], env->regwptr[3],
	env->regwptr[4], env->regwptr[5],
	0, 0);
	if (ret == -TARGET_ERESTARTSYS \|\| ret == -TARGET_QEMU_ESIGRETURN) {
	break;
	}
	if ((abi_ulong)ret >= (abi_ulong)(-515)) {
	#if defined(TARGET_SPARC64) && !defined(TARGET_ABI32)
	env->xcc \|= PSR_CARRY;
	#else
	env->psr \|= PSR_CARRY;
	#endif
	ret = -ret;
	} else {
	#if defined(TARGET_SPARC64) && !defined(TARGET_ABI32)
	env->xcc &= ~PSR_CARRY;
	#else
	env->psr &= ~PSR_CARRY;
	#endif
	}
	env->regwptr[0] = ret;
	/* next instruction */
	env->pc = env->npc;
	env->npc = env->npc + 4;
	break;
	case 0x83: /* flush windows */
	#ifdef TARGET_ABI32
	case 0x103:
	#endif
	flush_windows(env);
	/* next instruction */
	env->pc = env->npc;
	env->npc = env->npc + 4;
	break;
	#ifndef TARGET_SPARC64
	case TT_WIN_OVF: /* window overflow */
	save_window(env);
	break;
	case TT_WIN_UNF: /* window underflow */
	restore_window(env);
	break;
	case TT_TFAULT:
	case TT_DFAULT:
	{
	info.si_signo = TARGET_SIGSEGV;
	info.si_errno = 0;
	/* XXX: check env->error_code */
	info.si_code = TARGET_SEGV_MAPERR;
	info._sifields._sigfault._addr = env->mmuregs[4];
	queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
	}
	break;
	#else
	case TT_SPILL: /* window overflow */
	save_window(env);
	break;
	case TT_FILL: /* window underflow */
	restore_window(env);
	break;
	case TT_TFAULT:
	case TT_DFAULT:
	{
	info.si_signo = TARGET_SIGSEGV;
	info.si_errno = 0;
	/* XXX: check env->error_code */
	info.si_code = TARGET_SEGV_MAPERR;
	if (trapnr == TT_DFAULT)
	info._sifields._sigfault._addr = env->dmmu.mmuregs[4];
	else
	info._sifields._sigfault._addr = cpu_tsptr(env)->tpc;
	queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
	}
	break;
	#ifndef TARGET_ABI32
	case 0x16e:
	flush_windows(env);
	sparc64_get_context(env);
	break;
	case 0x16f:
	flush_windows(env);
	sparc64_set_context(env);
	break;
	#endif
	#endif
	case EXCP_INTERRUPT:
	/* just indicate that signals should be handled asap */
	break;
	case TT_ILL_INSN:
	{
	info.si_signo = TARGET_SIGILL;
	info.si_errno = 0;
	info.si_code = TARGET_ILL_ILLOPC;
	info._sifields._sigfault._addr = env->pc;
	queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
	}
	break;
	case EXCP_DEBUG:
	info.si_signo = TARGET_SIGTRAP;
	info.si_errno = 0;
	info.si_code = TARGET_TRAP_BRKPT;
	queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
	break;
	case EXCP_ATOMIC:
	cpu_exec_step_atomic(cs);
	break;
	default:
	fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr);
	cpu_dump_state(cs, stderr, 0);
	exit(EXIT_FAILURE);
	}
	process_pending_signals (env);
	}
	}

	void target_cpu_copy_regs(CPUArchState env, struct target_pt_regs regs)
	{
	int i;
	env->pc = regs->pc;
	env->npc = regs->npc;
	env->y = regs->y;
	for(i = 0; i < 8; i++)
	env->gregs[i] = regs->u_regs[i];
	for(i = 0; i < 8; i++)
	env->regwptr[i] = regs->u_regs[i + 8];
	}