target/xtensa/win_helper.c - third_party/qemu - Git at Google

 /*
  * Copyright (c) 2011 - 2019, Max Filippov, Open Source and Linux Lab.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *     * Redistributions of source code must retain the above copyright
  *       notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above copyright
  *       notice, this list of conditions and the following disclaimer in the
  *       documentation and/or other materials provided with the distribution.
  *     * Neither the name of the Open Source and Linux Lab nor the
  *       names of its contributors may be used to endorse or promote products
  *       derived from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 #include "qemu/osdep.h"
 #include "qemu/main-loop.h"
 #include "cpu.h"
 #include "exec/helper-proto.h"
 #include "qemu/host-utils.h"
 #include "exec/exec-all.h"

 static void copy_window_from_phys(CPUXtensaState *env,
                                   uint32_t window, uint32_t phys, uint32_t n)
 {
     assert(phys < env->config->nareg);
     if (phys + n <= env->config->nareg) {
         memcpy(env->regs + window, env->phys_regs + phys,
                n * sizeof(uint32_t));
     } else {
         uint32_t n1 = env->config->nareg - phys;
         memcpy(env->regs + window, env->phys_regs + phys,
                n1 * sizeof(uint32_t));
         memcpy(env->regs + window + n1, env->phys_regs,
                (n - n1) * sizeof(uint32_t));
     }
 }

 static void copy_phys_from_window(CPUXtensaState *env,
                                   uint32_t phys, uint32_t window, uint32_t n)
 {
     assert(phys < env->config->nareg);
     if (phys + n <= env->config->nareg) {
         memcpy(env->phys_regs + phys, env->regs + window,
                n * sizeof(uint32_t));
     } else {
         uint32_t n1 = env->config->nareg - phys;
         memcpy(env->phys_regs + phys, env->regs + window,
                n1 * sizeof(uint32_t));
         memcpy(env->phys_regs, env->regs + window + n1,
                (n - n1) * sizeof(uint32_t));
     }
 }

 static inline unsigned windowbase_bound(unsigned a, const CPUXtensaState *env)
 {
     return a & (env->config->nareg / 4 - 1);
 }

 static inline unsigned windowstart_bit(unsigned a, const CPUXtensaState *env)
 {
     return 1 << windowbase_bound(a, env);
 }

 void xtensa_sync_window_from_phys(CPUXtensaState *env)
 {
     copy_window_from_phys(env, 0, env->sregs[WINDOW_BASE] * 4, 16);
 }

 void xtensa_sync_phys_from_window(CPUXtensaState *env)
 {
     copy_phys_from_window(env, env->sregs[WINDOW_BASE] * 4, 0, 16);
 }

 static void xtensa_rotate_window_abs(CPUXtensaState *env, uint32_t position)
 {
     xtensa_sync_phys_from_window(env);
     env->sregs[WINDOW_BASE] = windowbase_bound(position, env);
     xtensa_sync_window_from_phys(env);
 }

 void xtensa_rotate_window(CPUXtensaState *env, uint32_t delta)
 {
     xtensa_rotate_window_abs(env, env->sregs[WINDOW_BASE] + delta);
 }

 void HELPER(sync_windowbase)(CPUXtensaState *env)
 {
     xtensa_rotate_window_abs(env, env->windowbase_next);
 }

 void HELPER(entry)(CPUXtensaState *env, uint32_t pc, uint32_t s, uint32_t imm)
 {
     int callinc = (env->sregs[PS] & PS_CALLINC) >> PS_CALLINC_SHIFT;

     env->regs[(callinc << 2) | (s & 3)] = env->regs[s] - imm;
     env->windowbase_next = env->sregs[WINDOW_BASE] + callinc;
     env->sregs[WINDOW_START] |= windowstart_bit(env->windowbase_next, env);
 }

 void HELPER(window_check)(CPUXtensaState *env, uint32_t pc, uint32_t w)
 {
     uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env);
     uint32_t windowstart = xtensa_replicate_windowstart(env) >>
         (env->sregs[WINDOW_BASE] + 1);
     uint32_t n = ctz32(windowstart) + 1;

     assert(n <= w);

     xtensa_rotate_window(env, n);
     env->sregs[PS] = (env->sregs[PS] & ~PS_OWB) |
         (windowbase << PS_OWB_SHIFT) | PS_EXCM;
     env->sregs[EPC1] = env->pc = pc;

     switch (ctz32(windowstart >> n)) {
     case 0:
         HELPER(exception)(env, EXC_WINDOW_OVERFLOW4);
         break;
     case 1:
         HELPER(exception)(env, EXC_WINDOW_OVERFLOW8);
         break;
     default:
         HELPER(exception)(env, EXC_WINDOW_OVERFLOW12);
         break;
     }
 }

 void HELPER(test_ill_retw)(CPUXtensaState *env, uint32_t pc)
 {
     int n = (env->regs[0] >> 30) & 0x3;
     int m = 0;
     uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env);
     uint32_t windowstart = env->sregs[WINDOW_START];

     if (windowstart & windowstart_bit(windowbase - 1, env)) {
         m = 1;
     } else if (windowstart & windowstart_bit(windowbase - 2, env)) {
         m = 2;
     } else if (windowstart & windowstart_bit(windowbase - 3, env)) {
         m = 3;
     }

     if (n == 0 || (m != 0 && m != n)) {
         qemu_log_mask(LOG_GUEST_ERROR, "Illegal retw instruction(pc = %08x), "
                       "PS = %08x, m = %d, n = %d\n",
                       pc, env->sregs[PS], m, n);
         HELPER(exception_cause)(env, pc, ILLEGAL_INSTRUCTION_CAUSE);
     }
 }

 void HELPER(test_underflow_retw)(CPUXtensaState *env, uint32_t pc)
 {
     int n = (env->regs[0] >> 30) & 0x3;

     if (!(env->sregs[WINDOW_START] &
           windowstart_bit(env->sregs[WINDOW_BASE] - n, env))) {
         uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env);

         xtensa_rotate_window(env, -n);
         /* window underflow */
         env->sregs[PS] = (env->sregs[PS] & ~PS_OWB) |
             (windowbase << PS_OWB_SHIFT) | PS_EXCM;
         env->sregs[EPC1] = env->pc = pc;

         if (n == 1) {
             HELPER(exception)(env, EXC_WINDOW_UNDERFLOW4);
         } else if (n == 2) {
             HELPER(exception)(env, EXC_WINDOW_UNDERFLOW8);
         } else if (n == 3) {
             HELPER(exception)(env, EXC_WINDOW_UNDERFLOW12);
         }
     }
 }

 void HELPER(retw)(CPUXtensaState *env, uint32_t a0)
 {
     int n = (a0 >> 30) & 0x3;

     xtensa_rotate_window(env, -n);
 }

 void xtensa_restore_owb(CPUXtensaState *env)
 {
     xtensa_rotate_window_abs(env, (env->sregs[PS] & PS_OWB) >> PS_OWB_SHIFT);
 }

 void HELPER(restore_owb)(CPUXtensaState *env)
 {
     xtensa_restore_owb(env);
 }

 void HELPER(movsp)(CPUXtensaState *env, uint32_t pc)
 {
     if ((env->sregs[WINDOW_START] &
          (windowstart_bit(env->sregs[WINDOW_BASE] - 3, env) |
           windowstart_bit(env->sregs[WINDOW_BASE] - 2, env) |
           windowstart_bit(env->sregs[WINDOW_BASE] - 1, env))) == 0) {
         HELPER(exception_cause)(env, pc, ALLOCA_CAUSE);
     }
 }
	/*
	* Copyright (c) 2011 - 2019, Max Filippov, Open Source and Linux Lab.
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are met:
	* * Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* * Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	* * Neither the name of the Open Source and Linux Lab nor the
	* names of its contributors may be used to endorse or promote products
	* derived from this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
	* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
	* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
	* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
	* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
	* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#include "qemu/osdep.h"
	#include "qemu/main-loop.h"
	#include "cpu.h"
	#include "exec/helper-proto.h"
	#include "qemu/host-utils.h"
	#include "exec/exec-all.h"

	static void copy_window_from_phys(CPUXtensaState *env,
	uint32_t window, uint32_t phys, uint32_t n)
	{
	assert(phys < env->config->nareg);
	if (phys + n <= env->config->nareg) {
	memcpy(env->regs + window, env->phys_regs + phys,
	n * sizeof(uint32_t));
	} else {
	uint32_t n1 = env->config->nareg - phys;
	memcpy(env->regs + window, env->phys_regs + phys,
	n1 * sizeof(uint32_t));
	memcpy(env->regs + window + n1, env->phys_regs,
	(n - n1) * sizeof(uint32_t));
	}
	}

	static void copy_phys_from_window(CPUXtensaState *env,
	uint32_t phys, uint32_t window, uint32_t n)
	{
	assert(phys < env->config->nareg);
	if (phys + n <= env->config->nareg) {
	memcpy(env->phys_regs + phys, env->regs + window,
	n * sizeof(uint32_t));
	} else {
	uint32_t n1 = env->config->nareg - phys;
	memcpy(env->phys_regs + phys, env->regs + window,
	n1 * sizeof(uint32_t));
	memcpy(env->phys_regs, env->regs + window + n1,
	(n - n1) * sizeof(uint32_t));
	}
	}

	static inline unsigned windowbase_bound(unsigned a, const CPUXtensaState *env)
	{
	return a & (env->config->nareg / 4 - 1);
	}

	static inline unsigned windowstart_bit(unsigned a, const CPUXtensaState *env)
	{
	return 1 << windowbase_bound(a, env);
	}

	void xtensa_sync_window_from_phys(CPUXtensaState *env)
	{
	copy_window_from_phys(env, 0, env->sregs[WINDOW_BASE] * 4, 16);
	}

	void xtensa_sync_phys_from_window(CPUXtensaState *env)
	{
	copy_phys_from_window(env, env->sregs[WINDOW_BASE] * 4, 0, 16);
	}

	static void xtensa_rotate_window_abs(CPUXtensaState *env, uint32_t position)
	{
	xtensa_sync_phys_from_window(env);
	env->sregs[WINDOW_BASE] = windowbase_bound(position, env);
	xtensa_sync_window_from_phys(env);
	}

	void xtensa_rotate_window(CPUXtensaState *env, uint32_t delta)
	{
	xtensa_rotate_window_abs(env, env->sregs[WINDOW_BASE] + delta);
	}

	void HELPER(sync_windowbase)(CPUXtensaState *env)
	{
	xtensa_rotate_window_abs(env, env->windowbase_next);
	}

	void HELPER(entry)(CPUXtensaState *env, uint32_t pc, uint32_t s, uint32_t imm)
	{
	int callinc = (env->sregs[PS] & PS_CALLINC) >> PS_CALLINC_SHIFT;

	env->regs[(callinc << 2) \| (s & 3)] = env->regs[s] - imm;
	env->windowbase_next = env->sregs[WINDOW_BASE] + callinc;
	env->sregs[WINDOW_START] \|= windowstart_bit(env->windowbase_next, env);
	}

	void HELPER(window_check)(CPUXtensaState *env, uint32_t pc, uint32_t w)
	{
	uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env);
	uint32_t windowstart = xtensa_replicate_windowstart(env) >>
	(env->sregs[WINDOW_BASE] + 1);
	uint32_t n = ctz32(windowstart) + 1;

	assert(n <= w);

	xtensa_rotate_window(env, n);
	env->sregs[PS] = (env->sregs[PS] & ~PS_OWB) \|
	(windowbase << PS_OWB_SHIFT) \| PS_EXCM;
	env->sregs[EPC1] = env->pc = pc;

	switch (ctz32(windowstart >> n)) {
	case 0:
	HELPER(exception)(env, EXC_WINDOW_OVERFLOW4);
	break;
	case 1:
	HELPER(exception)(env, EXC_WINDOW_OVERFLOW8);
	break;
	default:
	HELPER(exception)(env, EXC_WINDOW_OVERFLOW12);
	break;
	}
	}

	void HELPER(test_ill_retw)(CPUXtensaState *env, uint32_t pc)
	{
	int n = (env->regs[0] >> 30) & 0x3;
	int m = 0;
	uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env);
	uint32_t windowstart = env->sregs[WINDOW_START];

	if (windowstart & windowstart_bit(windowbase - 1, env)) {
	m = 1;
	} else if (windowstart & windowstart_bit(windowbase - 2, env)) {
	m = 2;
	} else if (windowstart & windowstart_bit(windowbase - 3, env)) {
	m = 3;
	}

	if (n == 0 \|\| (m != 0 && m != n)) {
	qemu_log_mask(LOG_GUEST_ERROR, "Illegal retw instruction(pc = %08x), "
	"PS = %08x, m = %d, n = %d\n",
	pc, env->sregs[PS], m, n);
	HELPER(exception_cause)(env, pc, ILLEGAL_INSTRUCTION_CAUSE);
	}
	}

	void HELPER(test_underflow_retw)(CPUXtensaState *env, uint32_t pc)
	{
	int n = (env->regs[0] >> 30) & 0x3;

	if (!(env->sregs[WINDOW_START] &
	windowstart_bit(env->sregs[WINDOW_BASE] - n, env))) {
	uint32_t windowbase = windowbase_bound(env->sregs[WINDOW_BASE], env);

	xtensa_rotate_window(env, -n);
	/* window underflow */
	env->sregs[PS] = (env->sregs[PS] & ~PS_OWB) \|
	(windowbase << PS_OWB_SHIFT) \| PS_EXCM;
	env->sregs[EPC1] = env->pc = pc;

	if (n == 1) {
	HELPER(exception)(env, EXC_WINDOW_UNDERFLOW4);
	} else if (n == 2) {
	HELPER(exception)(env, EXC_WINDOW_UNDERFLOW8);
	} else if (n == 3) {
	HELPER(exception)(env, EXC_WINDOW_UNDERFLOW12);
	}
	}
	}

	void HELPER(retw)(CPUXtensaState *env, uint32_t a0)
	{
	int n = (a0 >> 30) & 0x3;

	xtensa_rotate_window(env, -n);
	}

	void xtensa_restore_owb(CPUXtensaState *env)
	{
	xtensa_rotate_window_abs(env, (env->sregs[PS] & PS_OWB) >> PS_OWB_SHIFT);
	}

	void HELPER(restore_owb)(CPUXtensaState *env)
	{
	xtensa_restore_owb(env);
	}

	void HELPER(movsp)(CPUXtensaState *env, uint32_t pc)
	{
	if ((env->sregs[WINDOW_START] &
	(windowstart_bit(env->sregs[WINDOW_BASE] - 3, env) \|
	windowstart_bit(env->sregs[WINDOW_BASE] - 2, env) \|
	windowstart_bit(env->sregs[WINDOW_BASE] - 1, env))) == 0) {
	HELPER(exception_cause)(env, pc, ALLOCA_CAUSE);
	}
	}