302 // Exception handler checks the nmethod's implicit null checks table
303 // only when this method returns false.
304 #ifdef _LP64
305 if (UseCompressedOops && Universe::narrow_oop_base() != NULL) {
306 assert (Universe::heap() != NULL, "java heap should be initialized");
307 // The first page after heap_base is unmapped and
308 // the 'offset' is equal to [heap_base + offset] for
309 // narrow oop implicit null checks.
310 uintptr_t base = (uintptr_t)Universe::narrow_oop_base();
311 int adj = MIN2(0, UseShenandoahGC ? BrooksPointer::byte_offset() : 0);
312 if ((uintptr_t)(offset - adj) >= base) {
313 // Normalize offset for the next check.
314 offset = (intptr_t)(pointer_delta((void*)offset, (void*)base, 1));
315 }
316 }
317 #endif
318
319 if (UseShenandoahGC) {
320 #ifdef AARCH64
321 // AArch64 uses 48-bit addresses
322 const unsigned long address_bits = 0xfffffffffffful;
323 #elif defined(_LP64)
324 #ifdef _WINDOWS
325 const unsigned long long address_bits = 0xffffffffffffffffull;
326 #else
327 const unsigned long address_bits = 0xfffffffffffffffful;
328 #endif // _WINDOWS
329 #else
330 // Shenandoah is not implemented on these platforms, make sure we build fine,
331 // but also crash consistently at runtime.
332 const unsigned long address_bits = 0;
333 ShouldNotReachHere();
334 #endif
335 if ((offset & address_bits) == (BrooksPointer::byte_offset() & address_bits)) {
336 return false;
337 }
338 }
339
340 return offset < 0 || os::vm_page_size() <= offset;
341 }
|
302 // Exception handler checks the nmethod's implicit null checks table
303 // only when this method returns false.
304 #ifdef _LP64
305 if (UseCompressedOops && Universe::narrow_oop_base() != NULL) {
306 assert (Universe::heap() != NULL, "java heap should be initialized");
307 // The first page after heap_base is unmapped and
308 // the 'offset' is equal to [heap_base + offset] for
309 // narrow oop implicit null checks.
310 uintptr_t base = (uintptr_t)Universe::narrow_oop_base();
311 int adj = MIN2(0, UseShenandoahGC ? BrooksPointer::byte_offset() : 0);
312 if ((uintptr_t)(offset - adj) >= base) {
313 // Normalize offset for the next check.
314 offset = (intptr_t)(pointer_delta((void*)offset, (void*)base, 1));
315 }
316 }
317 #endif
318
319 if (UseShenandoahGC) {
320 #ifdef AARCH64
321 // AArch64 uses 48-bit addresses
322 const uintptr_t address_bits = (uintptr_t)0xfffffffffffful;
323 #elif defined(_LP64)
324 const uintptr_t address_bits = ~(uintptr_t)0;
325 #else
326 // Shenandoah is not implemented on these platforms, make sure we build fine,
327 // but also crash consistently at runtime.
328 const uintptr_t address_bits = 0;
329 ShouldNotReachHere();
330 #endif
331 if ((offset & address_bits) == (BrooksPointer::byte_offset() & address_bits)) {
332 return false;
333 }
334 }
335
336 return offset < 0 || os::vm_page_size() <= offset;
337 }
|