Index: runtime/vm/simulator_mips.h |
=================================================================== |
--- runtime/vm/simulator_mips.h (revision 41327) |
+++ runtime/vm/simulator_mips.h (working copy) |
@@ -17,11 +17,12 @@ |
#endif |
#include "vm/constants_mips.h" |
-#include "vm/object.h" |
namespace dart { |
class Isolate; |
+class Mutex; |
+class RawObject; |
class SimulatorSetjmpBuffer; |
class Simulator { |
@@ -110,6 +111,12 @@ |
bool fp_return = false, |
bool fp_args = false); |
+ // Implementation of atomic compare and exchange in the same synchronization |
+ // domain as other synchronization primitive instructions (e.g. ldrex, strex). |
+ static uword CompareExchange(uword* address, |
+ uword compare_value, |
+ uword new_value); |
+ |
// Runtime and native call support. |
enum CallKind { |
kRuntimeCall, |
@@ -190,6 +197,38 @@ |
inline double ReadD(uword addr, Instr* instr); |
inline void WriteD(uword addr, double value, Instr* instr); |
+ // In Dart, there is at most one thread per isolate. |
+ // We keep track of 16 exclusive access address tags across all isolates. |
+ // Since we cannot simulate a native context switch, which clears |
+ // the exclusive access state of the local monitor, we associate the isolate |
+ // requesting exclusive access to the address tag. |
+ // Multiple isolates requesting exclusive access (using the LL instruction) |
+ // to the same address will result in multiple address tags being created for |
+ // the same address, one per isolate. |
+ // At any given time, each isolate is associated to at most one address tag. |
+ static Mutex* exclusive_access_lock_; |
+ static const int kNumAddressTags = 16; |
+ static struct AddressTag { |
+ Isolate* isolate; |
+ uword addr; |
+ } exclusive_access_state_[kNumAddressTags]; |
+ static int next_address_tag_; |
+ |
+ // Synchronization primitives support. |
+ void ClearExclusive(); |
+ intptr_t ReadExclusiveW(uword addr, Instr* instr); |
+ intptr_t WriteExclusiveW(uword addr, intptr_t value, Instr* instr); |
+ |
+ // Set access to given address to 'exclusive state' for current isolate. |
+ static void SetExclusiveAccess(uword addr); |
+ |
+ // Returns true if the current isolate has exclusive access to given address, |
+ // returns false otherwise. In either case, set access to given address to |
+ // 'open state' for all isolates. |
+ // If given addr is NULL, set access to 'open state' for current |
+ // isolate (CLREX). |
+ static bool HasExclusiveAccessAndOpen(uword addr); |
+ |
void DoBranch(Instr* instr, bool taken, bool likely); |
void DoBreak(Instr *instr); |