exec: introduce memory_access_size

This will be used by address_space_access_valid too.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2013-05-24 11:59:43 +02:00
parent 2bbfa05d20
commit 82f2563fc8

27
exec.c
View File

@ -1868,6 +1868,17 @@ static inline bool memory_access_is_direct(MemoryRegion *mr, bool is_write)
return false;
}
static inline int memory_access_size(int l, hwaddr addr)
{
if (l >= 4 && ((addr & 3) == 0)) {
return 4;
}
if (l >= 2 && ((addr & 1) == 0)) {
return 2;
}
return 1;
}
void address_space_rw(AddressSpace *as, hwaddr addr, uint8_t *buf,
int len, bool is_write)
{
@ -1883,23 +1894,21 @@ void address_space_rw(AddressSpace *as, hwaddr addr, uint8_t *buf,
if (is_write) {
if (!memory_access_is_direct(section->mr, is_write)) {
l = memory_access_size(l, addr1);
/* XXX: could force cpu_single_env to NULL to avoid
potential bugs */
if (l >= 4 && ((addr1 & 3) == 0)) {
if (l == 4) {
/* 32 bit write access */
val = ldl_p(buf);
io_mem_write(section->mr, addr1, val, 4);
l = 4;
} else if (l >= 2 && ((addr1 & 1) == 0)) {
} else if (l == 2) {
/* 16 bit write access */
val = lduw_p(buf);
io_mem_write(section->mr, addr1, val, 2);
l = 2;
} else {
/* 8 bit write access */
val = ldub_p(buf);
io_mem_write(section->mr, addr1, val, 1);
l = 1;
}
} else {
addr1 += memory_region_get_ram_addr(section->mr);
@ -1911,21 +1920,19 @@ void address_space_rw(AddressSpace *as, hwaddr addr, uint8_t *buf,
} else {
if (!memory_access_is_direct(section->mr, is_write)) {
/* I/O case */
if (l >= 4 && ((addr1 & 3) == 0)) {
l = memory_access_size(l, addr1);
if (l == 4) {
/* 32 bit read access */
val = io_mem_read(section->mr, addr1, 4);
stl_p(buf, val);
l = 4;
} else if (l >= 2 && ((addr1 & 1) == 0)) {
} else if (l == 2) {
/* 16 bit read access */
val = io_mem_read(section->mr, addr1, 2);
stw_p(buf, val);
l = 2;
} else {
/* 8 bit read access */
val = io_mem_read(section->mr, addr1, 1);
stb_p(buf, val);
l = 1;
}
} else {
/* RAM case */