motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-03 15:53:54 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

target-m68k: Implement bitfield ops for memory

Browse source 
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <1478699171-10637-6-git-send-email-rth@twiddle.net>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
This commit is contained in:
Richard Henderson 2016-11-09 14:46:11 +01:00 • committed by Laurent Vivier
parent ac815f46a3
commit f2224f2c9a
4 changed files with 333 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

185
target/m68k/op_helper.c
View file

@ -469,3 +469,188 @@ void HELPER(cas2l)(CPUM68KState *env, uint32_t regs, uint32_t a1, uint32_t a2)
env->dregs[Dc1] = l1;
env->dregs[Dc2] = l2;
}
struct bf_data {
uint32_t addr;
uint32_t bofs;
uint32_t blen;
uint32_t len;
};
static struct bf_data bf_prep(uint32_t addr, int32_t ofs, uint32_t len)
{
int bofs, blen;
/* Bound length; map 0 to 32. */
len = ((len - 1) & 31) + 1;
/* Note that ofs is signed. */
addr += ofs / 8;
bofs = ofs % 8;
if (bofs < 0) {
bofs += 8;
addr -= 1;
}
/* Compute the number of bytes required (minus one) to
satisfy the bitfield. */
blen = (bofs + len - 1) / 8;
/* Canonicalize the bit offset for data loaded into a 64-bit big-endian
word. For the cases where BLEN is not a power of 2, adjust ADDR so
that we can use the next power of two sized load without crossing a
page boundary, unless the field itself crosses the boundary. */
switch (blen) {
case 0:
bofs += 56;
break;
case 1:
bofs += 48;
break;
case 2:
if (addr & 1) {
bofs += 8;
addr -= 1;
}
/* fallthru */
case 3:
bofs += 32;
break;
case 4:
if (addr & 3) {
bofs += 8 * (addr & 3);
addr &= -4;
}
break;
default:
g_assert_not_reached();
}
return (struct bf_data){
.addr = addr,
.bofs = bofs,
.blen = blen,
.len = len,
};
}
static uint64_t bf_load(CPUM68KState *env, uint32_t addr, int blen,
uintptr_t ra)
{
switch (blen) {
case 0:
return cpu_ldub_data_ra(env, addr, ra);
case 1:
return cpu_lduw_data_ra(env, addr, ra);
case 2:
case 3:
return cpu_ldl_data_ra(env, addr, ra);
case 4:
return cpu_ldq_data_ra(env, addr, ra);
default:
g_assert_not_reached();
}
}
static void bf_store(CPUM68KState *env, uint32_t addr, int blen,
uint64_t data, uintptr_t ra)
{
switch (blen) {
case 0:
cpu_stb_data_ra(env, addr, data, ra);
break;
case 1:
cpu_stw_data_ra(env, addr, data, ra);
break;
case 2:
case 3:
cpu_stl_data_ra(env, addr, data, ra);
break;
case 4:
cpu_stq_data_ra(env, addr, data, ra);
break;
default:
g_assert_not_reached();
}
}
uint32_t HELPER(bfexts_mem)(CPUM68KState *env, uint32_t addr,
int32_t ofs, uint32_t len)
{
uintptr_t ra = GETPC();
struct bf_data d = bf_prep(addr, ofs, len);
uint64_t data = bf_load(env, d.addr, d.blen, ra);
return (int64_t)(data << d.bofs) >> (64 - d.len);
}
uint64_t HELPER(bfextu_mem)(CPUM68KState *env, uint32_t addr,
int32_t ofs, uint32_t len)
{
uintptr_t ra = GETPC();
struct bf_data d = bf_prep(addr, ofs, len);
uint64_t data = bf_load(env, d.addr, d.blen, ra);
/* Put CC_N at the top of the high word; put the zero-extended value
at the bottom of the low word. */
data <<= d.bofs;
data >>= 64 - d.len;
data |= data << (64 - d.len);
return data;
}
uint32_t HELPER(bfins_mem)(CPUM68KState *env, uint32_t addr, uint32_t val,
int32_t ofs, uint32_t len)
{
uintptr_t ra = GETPC();
struct bf_data d = bf_prep(addr, ofs, len);
uint64_t data = bf_load(env, d.addr, d.blen, ra);
uint64_t mask = -1ull << (64 - d.len) >> d.bofs;
data = (data & ~mask) | (((uint64_t)val << (64 - d.len)) >> d.bofs);
bf_store(env, d.addr, d.blen, data, ra);
/* The field at the top of the word is also CC_N for CC_OP_LOGIC. */
return val << (32 - d.len);
}
uint32_t HELPER(bfchg_mem)(CPUM68KState *env, uint32_t addr,
int32_t ofs, uint32_t len)
{
uintptr_t ra = GETPC();
struct bf_data d = bf_prep(addr, ofs, len);
uint64_t data = bf_load(env, d.addr, d.blen, ra);
uint64_t mask = -1ull << (64 - d.len) >> d.bofs;
bf_store(env, d.addr, d.blen, data ^ mask, ra);
return ((data & mask) << d.bofs) >> 32;
}
uint32_t HELPER(bfclr_mem)(CPUM68KState *env, uint32_t addr,
int32_t ofs, uint32_t len)
{
uintptr_t ra = GETPC();
struct bf_data d = bf_prep(addr, ofs, len);
uint64_t data = bf_load(env, d.addr, d.blen, ra);
uint64_t mask = -1ull << (64 - d.len) >> d.bofs;
bf_store(env, d.addr, d.blen, data & ~mask, ra);
return ((data & mask) << d.bofs) >> 32;
}
uint32_t HELPER(bfset_mem)(CPUM68KState *env, uint32_t addr,
int32_t ofs, uint32_t len)
{
uintptr_t ra = GETPC();
struct bf_data d = bf_prep(addr, ofs, len);
uint64_t data = bf_load(env, d.addr, d.blen, ra);
uint64_t mask = -1ull << (64 - d.len) >> d.bofs;
bf_store(env, d.addr, d.blen, data | mask, ra);
return ((data & mask) << d.bofs) >> 32;
}