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8016697: Use stubs to implement safefetch

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Implement Safefetch as stub routines. This reduces compiler and os dependencies.

Reviewed-by: twisti, kvn
This commit is contained in:
Goetz Lindenmaier 2013-06-20 15:02:05 +02:00
parent b5efe058f7
commit ef69ce852c
21 changed files with 231 additions and 304 deletions
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47
hotspot/src/share/vm/runtime/stubRoutines.hpp
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@ -221,6 +221,14 @@ class StubRoutines: AllStatic {
static double (*_intrinsic_cos)(double);
static double (*_intrinsic_tan)(double);
// Safefetch stubs.
static address _safefetch32_entry;
static address _safefetch32_fault_pc;
static address _safefetch32_continuation_pc;
static address _safefetchN_entry;
static address _safefetchN_fault_pc;
static address _safefetchN_continuation_pc;
public:
// Initialization/Testing
static void initialize1(); // must happen before universe::genesis
@ -381,6 +389,34 @@ class StubRoutines: AllStatic {
return _intrinsic_tan(d);
}
//
// Safefetch stub support
//
typedef int (*SafeFetch32Stub)(int* adr, int errValue);
typedef intptr_t (*SafeFetchNStub) (intptr_t* adr, intptr_t errValue);
static SafeFetch32Stub SafeFetch32_stub() { return CAST_TO_FN_PTR(SafeFetch32Stub, _safefetch32_entry); }
static SafeFetchNStub SafeFetchN_stub() { return CAST_TO_FN_PTR(SafeFetchNStub, _safefetchN_entry); }
static bool is_safefetch_fault(address pc) {
return pc != NULL &&
(pc == _safefetch32_fault_pc ||
pc == _safefetchN_fault_pc);
}
static address continuation_for_safefetch_fault(address pc) {
assert(_safefetch32_continuation_pc != NULL &&
_safefetchN_continuation_pc != NULL,
"not initialized");
if (pc == _safefetch32_fault_pc) return _safefetch32_continuation_pc;
if (pc == _safefetchN_fault_pc) return _safefetchN_continuation_pc;
ShouldNotReachHere();
return NULL;
}
//
// Default versions of the above arraycopy functions for platforms which do
// not have specialized versions
@ -400,4 +436,15 @@ class StubRoutines: AllStatic {
static void arrayof_oop_copy_uninit(HeapWord* src, HeapWord* dest, size_t count);
};
// Safefetch allows to load a value from a location that's not known
// to be valid. If the load causes a fault, the error value is returned.
inline int SafeFetch32(int* adr, int errValue) {
assert(StubRoutines::SafeFetch32_stub(), "stub not yet generated");
return StubRoutines::SafeFetch32_stub()(adr, errValue);
}
inline intptr_t SafeFetchN(intptr_t* adr, intptr_t errValue) {
assert(StubRoutines::SafeFetchN_stub(), "stub not yet generated");
return StubRoutines::SafeFetchN_stub()(adr, errValue);
}
#endif // SHARE_VM_RUNTIME_STUBROUTINES_HPP