JDK14/Java14源码在线阅读
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*
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#ifndef CPU_PPC_BYTES_PPC_HPP
#define CPU_PPC_BYTES_PPC_HPP
#include "memory/allocation.hpp"
class Bytes: AllStatic {
public:
// Efficient reading and writing of unaligned unsigned data in platform-specific byte ordering
// PowerPC needs to check for alignment.
// Can I count on address always being a pointer to an unsigned char? Yes.
#if defined(VM_LITTLE_ENDIAN)
// Forward declarations of the compiler-dependent implementation
static inline u2 swap_u2(u2 x);
static inline u4 swap_u4(u4 x);
static inline u8 swap_u8(u8 x);
static inline u2 get_native_u2(address p) {
return (intptr_t(p) & 1) == 0
? *(u2*)p
: ( u2(p[1]) << 8 )
| ( u2(p[0]) );
}
static inline u4 get_native_u4(address p) {
switch (intptr_t(p) & 3) {
case 0: return *(u4*)p;
case 2: return ( u4( ((u2*)p)[1] ) << 16 )
| ( u4( ((u2*)p)[0] ) );
default: return ( u4(p[3]) << 24 )
| ( u4(p[2]) << 16 )
| ( u4(p[1]) << 8 )
| u4(p[0]);
}
}
static inline u8 get_native_u8(address p) {
switch (intptr_t(p) & 7) {
case 0: return *(u8*)p;
case 4: return ( u8( ((u4*)p)[1] ) << 32 )
| ( u8( ((u4*)p)[0] ) );
case 2: return ( u8( ((u2*)p)[3] ) << 48 )
| ( u8( ((u2*)p)[2] ) << 32 )
| ( u8( ((u2*)p)[1] ) << 16 )
| ( u8( ((u2*)p)[0] ) );
default: return ( u8(p[7]) << 56 )
| ( u8(p[6]) << 48 )
| ( u8(p[5]) << 40 )
| ( u8(p[4]) << 32 )
| ( u8(p[3]) << 24 )
| ( u8(p[2]) << 16 )
| ( u8(p[1]) << 8 )
| u8(p[0]);
}
}
static inline void put_native_u2(address p, u2 x) {
if ( (intptr_t(p) & 1) == 0 ) *(u2*)p = x;
else {
p[1] = x >> 8;
p[0] = x;
}
}
static inline void put_native_u4(address p, u4 x) {
switch ( intptr_t(p) & 3 ) {
case 0: *(u4*)p = x;
break;
case 2: ((u2*)p)[1] = x >> 16;
((u2*)p)[0] = x;
break;
default: ((u1*)p)[3] = x >> 24;
((u1*)p)[2] = x >> 16;
((u1*)p)[1] = x >> 8;
((u1*)p)[0] = x;
break;
}
}
static inline void put_native_u8(address p, u8 x) {
switch ( intptr_t(p) & 7 ) {
case 0: *(u8*)p = x;
break;
case 4: ((u4*)p)[1] = x >> 32;
((u4*)p)[0] = x;
break;
case 2: ((u2*)p)[3] = x >> 48;
((u2*)p)[2] = x >> 32;
((u2*)p)[1] = x >> 16;
((u2*)p)[0] = x;
break;
default: ((u1*)p)[7] = x >> 56;
((u1*)p)[6] = x >> 48;
((u1*)p)[5] = x >> 40;
((u1*)p)[4] = x >> 32;
((u1*)p)[3] = x >> 24;
((u1*)p)[2] = x >> 16;
((u1*)p)[1] = x >> 8;
((u1*)p)[0] = x;
}
}
// Efficient reading and writing of unaligned unsigned data in Java byte ordering (i.e. big-endian ordering)
// (no byte-order reversal is needed since Power CPUs are big-endian oriented).
static inline u2 get_Java_u2(address p) { return swap_u2(get_native_u2(p)); }
static inline u4 get_Java_u4(address p) { return swap_u4(get_native_u4(p)); }
static inline u8 get_Java_u8(address p) { return swap_u8(get_native_u8(p)); }
static inline void put_Java_u2(address p, u2 x) { put_native_u2(p, swap_u2(x)); }
static inline void put_Java_u4(address p, u4 x) { put_native_u4(p, swap_u4(x)); }
static inline void put_Java_u8(address p, u8 x) { put_native_u8(p, swap_u8(x)); }
#else // !defined(VM_LITTLE_ENDIAN)
// Thus, a swap between native and Java ordering is always a no-op:
static inline u2 swap_u2(u2 x) { return x; }
static inline u4 swap_u4(u4 x) { return x; }
static inline u8 swap_u8(u8 x) { return x; }
static inline u2 get_native_u2(address p) {
return (intptr_t(p) & 1) == 0
? *(u2*)p
: ( u2(p[0]) << 8 )
| ( u2(p[1]) );
}
static inline u4 get_native_u4(address p) {
switch (intptr_t(p) & 3) {
case 0: return *(u4*)p;
case 2: return ( u4( ((u2*)p)[0] ) << 16 )
| ( u4( ((u2*)p)[1] ) );
default: return ( u4(p[0]) << 24 )
| ( u4(p[1]) << 16 )
| ( u4(p[2]) << 8 )
| u4(p[3]);
}
}
static inline u8 get_native_u8(address p) {
switch (intptr_t(p) & 7) {
case 0: return *(u8*)p;
case 4: return ( u8( ((u4*)p)[0] ) << 32 )
| ( u8( ((u4*)p)[1] ) );
case 2: return ( u8( ((u2*)p)[0] ) << 48 )
| ( u8( ((u2*)p)[1] ) << 32 )
| ( u8( ((u2*)p)[2] ) << 16 )
| ( u8( ((u2*)p)[3] ) );
default: return ( u8(p[0]) << 56 )
| ( u8(p[1]) << 48 )
| ( u8(p[2]) << 40 )
| ( u8(p[3]) << 32 )
| ( u8(p[4]) << 24 )
| ( u8(p[5]) << 16 )
| ( u8(p[6]) << 8 )
| u8(p[7]);
}
}
static inline void put_native_u2(address p, u2 x) {
if ( (intptr_t(p) & 1) == 0 ) { *(u2*)p = x; }
else {
p[0] = x >> 8;
p[1] = x;
}
}
static inline void put_native_u4(address p, u4 x) {
switch ( intptr_t(p) & 3 ) {
case 0: *(u4*)p = x;
break;
case 2: ((u2*)p)[0] = x >> 16;
((u2*)p)[1] = x;
break;
default: ((u1*)p)[0] = x >> 24;
((u1*)p)[1] = x >> 16;
((u1*)p)[2] = x >> 8;
((u1*)p)[3] = x;
break;
}
}
static inline void put_native_u8(address p, u8 x) {
switch ( intptr_t(p) & 7 ) {
case 0: *(u8*)p = x;
break;
case 4: ((u4*)p)[0] = x >> 32;
((u4*)p)[1] = x;
break;
case 2: ((u2*)p)[0] = x >> 48;
((u2*)p)[1] = x >> 32;
((u2*)p)[2] = x >> 16;
((u2*)p)[3] = x;
break;
default: ((u1*)p)[0] = x >> 56;
((u1*)p)[1] = x >> 48;
((u1*)p)[2] = x >> 40;
((u1*)p)[3] = x >> 32;
((u1*)p)[4] = x >> 24;
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