xemu/target-cris/op_helper.c
Edgar E. Iglesias 95475216f2 crisv10: Always clear the V and C flags on btst.
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
2010-02-15 11:20:30 +01:00

654 lines
14 KiB
C

/*
* CRIS helper routines
*
* Copyright (c) 2007 AXIS Communications
* Written by Edgar E. Iglesias
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "exec.h"
#include "mmu.h"
#include "helper.h"
#include "host-utils.h"
//#define CRIS_OP_HELPER_DEBUG
#ifdef CRIS_OP_HELPER_DEBUG
#define D(x) x
#define D_LOG(...) qemu_log(__VA__ARGS__)
#else
#define D(x)
#define D_LOG(...) do { } while (0)
#endif
#if !defined(CONFIG_USER_ONLY)
#define MMUSUFFIX _mmu
#define SHIFT 0
#include "softmmu_template.h"
#define SHIFT 1
#include "softmmu_template.h"
#define SHIFT 2
#include "softmmu_template.h"
#define SHIFT 3
#include "softmmu_template.h"
/* Try to fill the TLB and return an exception if error. If retaddr is
NULL, it means that the function was called in C code (i.e. not
from generated code or from helper.c) */
/* XXX: fix it to restore all registers */
void tlb_fill (target_ulong addr, int is_write, int mmu_idx, void *retaddr)
{
TranslationBlock *tb;
CPUState *saved_env;
unsigned long pc;
int ret;
/* XXX: hack to restore env in all cases, even if not called from
generated code */
saved_env = env;
env = cpu_single_env;
D_LOG("%s pc=%x tpc=%x ra=%x\n", __func__,
env->pc, env->debug1, retaddr);
ret = cpu_cris_handle_mmu_fault(env, addr, is_write, mmu_idx, 1);
if (unlikely(ret)) {
if (retaddr) {
/* now we have a real cpu fault */
pc = (unsigned long)retaddr;
tb = tb_find_pc(pc);
if (tb) {
/* the PC is inside the translated code. It means that we have
a virtual CPU fault */
cpu_restore_state(tb, env, pc, NULL);
/* Evaluate flags after retranslation. */
helper_top_evaluate_flags();
}
}
cpu_loop_exit();
}
env = saved_env;
}
#endif
void helper_raise_exception(uint32_t index)
{
env->exception_index = index;
cpu_loop_exit();
}
void helper_tlb_flush_pid(uint32_t pid)
{
#if !defined(CONFIG_USER_ONLY)
pid &= 0xff;
if (pid != (env->pregs[PR_PID] & 0xff))
cris_mmu_flush_pid(env, env->pregs[PR_PID]);
#endif
}
void helper_spc_write(uint32_t new_spc)
{
#if !defined(CONFIG_USER_ONLY)
tlb_flush_page(env, env->pregs[PR_SPC]);
tlb_flush_page(env, new_spc);
#endif
}
void helper_dump(uint32_t a0, uint32_t a1, uint32_t a2)
{
qemu_log("%s: a0=%x a1=%x\n", __func__, a0, a1);
}
/* Used by the tlb decoder. */
#define EXTRACT_FIELD(src, start, end) \
(((src) >> start) & ((1 << (end - start + 1)) - 1))
void helper_movl_sreg_reg (uint32_t sreg, uint32_t reg)
{
uint32_t srs;
srs = env->pregs[PR_SRS];
srs &= 3;
env->sregs[srs][sreg] = env->regs[reg];
#if !defined(CONFIG_USER_ONLY)
if (srs == 1 || srs == 2) {
if (sreg == 6) {
/* Writes to tlb-hi write to mm_cause as a side
effect. */
env->sregs[SFR_RW_MM_TLB_HI] = env->regs[reg];
env->sregs[SFR_R_MM_CAUSE] = env->regs[reg];
}
else if (sreg == 5) {
uint32_t set;
uint32_t idx;
uint32_t lo, hi;
uint32_t vaddr;
int tlb_v;
idx = set = env->sregs[SFR_RW_MM_TLB_SEL];
set >>= 4;
set &= 3;
idx &= 15;
/* We've just made a write to tlb_lo. */
lo = env->sregs[SFR_RW_MM_TLB_LO];
/* Writes are done via r_mm_cause. */
hi = env->sregs[SFR_R_MM_CAUSE];
vaddr = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].hi,
13, 31);
vaddr <<= TARGET_PAGE_BITS;
tlb_v = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].lo,
3, 3);
env->tlbsets[srs - 1][set][idx].lo = lo;
env->tlbsets[srs - 1][set][idx].hi = hi;
D_LOG("tlb flush vaddr=%x v=%d pc=%x\n",
vaddr, tlb_v, env->pc);
tlb_flush_page(env, vaddr);
}
}
#endif
}
void helper_movl_reg_sreg (uint32_t reg, uint32_t sreg)
{
uint32_t srs;
env->pregs[PR_SRS] &= 3;
srs = env->pregs[PR_SRS];
#if !defined(CONFIG_USER_ONLY)
if (srs == 1 || srs == 2)
{
uint32_t set;
uint32_t idx;
uint32_t lo, hi;
idx = set = env->sregs[SFR_RW_MM_TLB_SEL];
set >>= 4;
set &= 3;
idx &= 15;
/* Update the mirror regs. */
hi = env->tlbsets[srs - 1][set][idx].hi;
lo = env->tlbsets[srs - 1][set][idx].lo;
env->sregs[SFR_RW_MM_TLB_HI] = hi;
env->sregs[SFR_RW_MM_TLB_LO] = lo;
}
#endif
env->regs[reg] = env->sregs[srs][sreg];
}
static void cris_ccs_rshift(CPUState *env)
{
uint32_t ccs;
/* Apply the ccs shift. */
ccs = env->pregs[PR_CCS];
ccs = (ccs & 0xc0000000) | ((ccs & 0x0fffffff) >> 10);
if (ccs & U_FLAG)
{
/* Enter user mode. */
env->ksp = env->regs[R_SP];
env->regs[R_SP] = env->pregs[PR_USP];
}
env->pregs[PR_CCS] = ccs;
}
void helper_rfe(void)
{
int rflag = env->pregs[PR_CCS] & R_FLAG;
D_LOG("rfe: erp=%x pid=%x ccs=%x btarget=%x\n",
env->pregs[PR_ERP], env->pregs[PR_PID],
env->pregs[PR_CCS],
env->btarget);
cris_ccs_rshift(env);
/* RFE sets the P_FLAG only if the R_FLAG is not set. */
if (!rflag)
env->pregs[PR_CCS] |= P_FLAG;
}
void helper_rfn(void)
{
int rflag = env->pregs[PR_CCS] & R_FLAG;
D_LOG("rfn: erp=%x pid=%x ccs=%x btarget=%x\n",
env->pregs[PR_ERP], env->pregs[PR_PID],
env->pregs[PR_CCS],
env->btarget);
cris_ccs_rshift(env);
/* Set the P_FLAG only if the R_FLAG is not set. */
if (!rflag)
env->pregs[PR_CCS] |= P_FLAG;
/* Always set the M flag. */
env->pregs[PR_CCS] |= M_FLAG;
}
uint32_t helper_lz(uint32_t t0)
{
return clz32(t0);
}
uint32_t helper_btst(uint32_t t0, uint32_t t1, uint32_t ccs)
{
/* FIXME: clean this up. */
/* des ref:
The N flag is set according to the selected bit in the dest reg.
The Z flag is set if the selected bit and all bits to the right are
zero.
The X flag is cleared.
Other flags are left untouched.
The destination reg is not affected.*/
unsigned int fz, sbit, bset, mask, masked_t0;
sbit = t1 & 31;
bset = !!(t0 & (1 << sbit));
mask = sbit == 31 ? -1 : (1 << (sbit + 1)) - 1;
masked_t0 = t0 & mask;
fz = !(masked_t0 | bset);
/* Clear the X, N and Z flags. */
ccs = ccs & ~(X_FLAG | N_FLAG | Z_FLAG);
if (env->pregs[PR_VR] < 32)
ccs &= ~(V_FLAG | C_FLAG);
/* Set the N and Z flags accordingly. */
ccs |= (bset << 3) | (fz << 2);
return ccs;
}
static inline uint32_t evaluate_flags_writeback(uint32_t flags, uint32_t ccs)
{
unsigned int x, z, mask;
/* Extended arithmetics, leave the z flag alone. */
x = env->cc_x;
mask = env->cc_mask | X_FLAG;
if (x) {
z = flags & Z_FLAG;
mask = mask & ~z;
}
flags &= mask;
/* all insn clear the x-flag except setf or clrf. */
ccs &= ~mask;
ccs |= flags;
return ccs;
}
uint32_t helper_evaluate_flags_muls(uint32_t ccs, uint32_t res, uint32_t mof)
{
uint32_t flags = 0;
int64_t tmp;
int dneg;
dneg = ((int32_t)res) < 0;
tmp = mof;
tmp <<= 32;
tmp |= res;
if (tmp == 0)
flags |= Z_FLAG;
else if (tmp < 0)
flags |= N_FLAG;
if ((dneg && mof != -1)
|| (!dneg && mof != 0))
flags |= V_FLAG;
return evaluate_flags_writeback(flags, ccs);
}
uint32_t helper_evaluate_flags_mulu(uint32_t ccs, uint32_t res, uint32_t mof)
{
uint32_t flags = 0;
uint64_t tmp;
tmp = mof;
tmp <<= 32;
tmp |= res;
if (tmp == 0)
flags |= Z_FLAG;
else if (tmp >> 63)
flags |= N_FLAG;
if (mof)
flags |= V_FLAG;
return evaluate_flags_writeback(flags, ccs);
}
uint32_t helper_evaluate_flags_mcp(uint32_t ccs,
uint32_t src, uint32_t dst, uint32_t res)
{
uint32_t flags = 0;
src = src & 0x80000000;
dst = dst & 0x80000000;
if ((res & 0x80000000L) != 0L)
{
flags |= N_FLAG;
if (!src && !dst)
flags |= V_FLAG;
else if (src & dst)
flags |= R_FLAG;
}
else
{
if (res == 0L)
flags |= Z_FLAG;
if (src & dst)
flags |= V_FLAG;
if (dst | src)
flags |= R_FLAG;
}
return evaluate_flags_writeback(flags, ccs);
}
uint32_t helper_evaluate_flags_alu_4(uint32_t ccs,
uint32_t src, uint32_t dst, uint32_t res)
{
uint32_t flags = 0;
src = src & 0x80000000;
dst = dst & 0x80000000;
if ((res & 0x80000000L) != 0L)
{
flags |= N_FLAG;
if (!src && !dst)
flags |= V_FLAG;
else if (src & dst)
flags |= C_FLAG;
}
else
{
if (res == 0L)
flags |= Z_FLAG;
if (src & dst)
flags |= V_FLAG;
if (dst | src)
flags |= C_FLAG;
}
return evaluate_flags_writeback(flags, ccs);
}
uint32_t helper_evaluate_flags_sub_4(uint32_t ccs,
uint32_t src, uint32_t dst, uint32_t res)
{
uint32_t flags = 0;
src = (~src) & 0x80000000;
dst = dst & 0x80000000;
if ((res & 0x80000000L) != 0L)
{
flags |= N_FLAG;
if (!src && !dst)
flags |= V_FLAG;
else if (src & dst)
flags |= C_FLAG;
}
else
{
if (res == 0L)
flags |= Z_FLAG;
if (src & dst)
flags |= V_FLAG;
if (dst | src)
flags |= C_FLAG;
}
flags ^= C_FLAG;
return evaluate_flags_writeback(flags, ccs);
}
uint32_t helper_evaluate_flags_move_4(uint32_t ccs, uint32_t res)
{
uint32_t flags = 0;
if ((int32_t)res < 0)
flags |= N_FLAG;
else if (res == 0L)
flags |= Z_FLAG;
return evaluate_flags_writeback(flags, ccs);
}
uint32_t helper_evaluate_flags_move_2(uint32_t ccs, uint32_t res)
{
uint32_t flags = 0;
if ((int16_t)res < 0L)
flags |= N_FLAG;
else if (res == 0)
flags |= Z_FLAG;
return evaluate_flags_writeback(flags, ccs);
}
/* TODO: This is expensive. We could split things up and only evaluate part of
CCR on a need to know basis. For now, we simply re-evaluate everything. */
void helper_evaluate_flags(void)
{
uint32_t src, dst, res;
uint32_t flags = 0;
src = env->cc_src;
dst = env->cc_dest;
res = env->cc_result;
if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
src = ~src;
/* Now, evaluate the flags. This stuff is based on
Per Zander's CRISv10 simulator. */
switch (env->cc_size)
{
case 1:
if ((res & 0x80L) != 0L)
{
flags |= N_FLAG;
if (((src & 0x80L) == 0L)
&& ((dst & 0x80L) == 0L))
{
flags |= V_FLAG;
}
else if (((src & 0x80L) != 0L)
&& ((dst & 0x80L) != 0L))
{
flags |= C_FLAG;
}
}
else
{
if ((res & 0xFFL) == 0L)
{
flags |= Z_FLAG;
}
if (((src & 0x80L) != 0L)
&& ((dst & 0x80L) != 0L))
{
flags |= V_FLAG;
}
if ((dst & 0x80L) != 0L
|| (src & 0x80L) != 0L)
{
flags |= C_FLAG;
}
}
break;
case 2:
if ((res & 0x8000L) != 0L)
{
flags |= N_FLAG;
if (((src & 0x8000L) == 0L)
&& ((dst & 0x8000L) == 0L))
{
flags |= V_FLAG;
}
else if (((src & 0x8000L) != 0L)
&& ((dst & 0x8000L) != 0L))
{
flags |= C_FLAG;
}
}
else
{
if ((res & 0xFFFFL) == 0L)
{
flags |= Z_FLAG;
}
if (((src & 0x8000L) != 0L)
&& ((dst & 0x8000L) != 0L))
{
flags |= V_FLAG;
}
if ((dst & 0x8000L) != 0L
|| (src & 0x8000L) != 0L)
{
flags |= C_FLAG;
}
}
break;
case 4:
if ((res & 0x80000000L) != 0L)
{
flags |= N_FLAG;
if (((src & 0x80000000L) == 0L)
&& ((dst & 0x80000000L) == 0L))
{
flags |= V_FLAG;
}
else if (((src & 0x80000000L) != 0L) &&
((dst & 0x80000000L) != 0L))
{
flags |= C_FLAG;
}
}
else
{
if (res == 0L)
flags |= Z_FLAG;
if (((src & 0x80000000L) != 0L)
&& ((dst & 0x80000000L) != 0L))
flags |= V_FLAG;
if ((dst & 0x80000000L) != 0L
|| (src & 0x80000000L) != 0L)
flags |= C_FLAG;
}
break;
default:
break;
}
if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
flags ^= C_FLAG;
env->pregs[PR_CCS] = evaluate_flags_writeback(flags, env->pregs[PR_CCS]);
}
void helper_top_evaluate_flags(void)
{
switch (env->cc_op)
{
case CC_OP_MCP:
env->pregs[PR_CCS] = helper_evaluate_flags_mcp(
env->pregs[PR_CCS], env->cc_src,
env->cc_dest, env->cc_result);
break;
case CC_OP_MULS:
env->pregs[PR_CCS] = helper_evaluate_flags_muls(
env->pregs[PR_CCS], env->cc_result,
env->pregs[PR_MOF]);
break;
case CC_OP_MULU:
env->pregs[PR_CCS] = helper_evaluate_flags_mulu(
env->pregs[PR_CCS], env->cc_result,
env->pregs[PR_MOF]);
break;
case CC_OP_MOVE:
case CC_OP_AND:
case CC_OP_OR:
case CC_OP_XOR:
case CC_OP_ASR:
case CC_OP_LSR:
case CC_OP_LSL:
switch (env->cc_size)
{
case 4:
env->pregs[PR_CCS] =
helper_evaluate_flags_move_4(
env->pregs[PR_CCS],
env->cc_result);
break;
case 2:
env->pregs[PR_CCS] =
helper_evaluate_flags_move_2(
env->pregs[PR_CCS],
env->cc_result);
break;
default:
helper_evaluate_flags();
break;
}
break;
case CC_OP_FLAGS:
/* live. */
break;
case CC_OP_SUB:
case CC_OP_CMP:
if (env->cc_size == 4)
env->pregs[PR_CCS] =
helper_evaluate_flags_sub_4(
env->pregs[PR_CCS],
env->cc_src, env->cc_dest,
env->cc_result);
else
helper_evaluate_flags();
break;
default:
{
switch (env->cc_size)
{
case 4:
env->pregs[PR_CCS] =
helper_evaluate_flags_alu_4(
env->pregs[PR_CCS],
env->cc_src, env->cc_dest,
env->cc_result);
break;
default:
helper_evaluate_flags();
break;
}
}
break;
}
}