1 files changed, 530 insertions, 0 deletions
diff --git a/js/src/jit/mips-shared/AtomicOperations-mips-shared.h b/js/src/jit/mips-shared/AtomicOperations-mips-shared.h
new file mode 100644
index 0000000000..e3484f3f78
--- /dev/null
+++ b/js/src/jit/mips-shared/AtomicOperations-mips-shared.h
@@ -0,0 +1,530 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* For documentation, see jit/AtomicOperations.h */
+
+// NOTE, MIPS32 unlike MIPS64 doesn't provide hardware support for lock-free
+// 64-bit atomics. We lie down below about 8-byte atomics being always lock-
+// free in order to support wasm jit. The 64-bit atomic for MIPS32 do not use
+// __atomic intrinsic and therefore do not relay on -latomic.
+// Access to a aspecific 64-bit variable in memory is protected by an
+// AddressLock whose instance is shared between jit and AtomicOperations.
+
+#ifndef jit_mips_shared_AtomicOperations_mips_shared_h
+#define jit_mips_shared_AtomicOperations_mips_shared_h
+
+#include "mozilla/Assertions.h"
+#include "mozilla/Types.h"
+
+#include "builtin/AtomicsObject.h"
+#include "vm/Uint8Clamped.h"
+
+#if !defined(__clang__) && !defined(__GNUC__)
+#  error "This file only for gcc-compatible compilers"
+#endif
+
+#if defined(JS_SIMULATOR_MIPS32) && !defined(__i386__)
+#  error "The MIPS32 simulator atomics assume x86"
+#endif
+
+namespace js {
+namespace jit {
+
+#if !defined(JS_64BIT)
+
+struct AddressLock {
+ public:
+  void acquire();
+  void release();
+
+ private:
+  uint32_t spinlock;
+};
+
+static_assert(sizeof(AddressLock) == sizeof(uint32_t),
+              "AddressLock must be 4 bytes for it to be consumed by jit");
+
+// For now use a single global AddressLock.
+static AddressLock gAtomic64Lock;
+
+struct MOZ_RAII AddressGuard {
+  explicit AddressGuard(void* addr) { gAtomic64Lock.acquire(); }
+
+  ~AddressGuard() { gAtomic64Lock.release(); }
+};
+
+#endif
+
+}  // namespace jit
+}  // namespace js
+
+inline bool js::jit::AtomicOperations::Initialize() {
+  // Nothing
+  return true;
+}
+
+inline void js::jit::AtomicOperations::ShutDown() {
+  // Nothing
+}
+
+inline bool js::jit::AtomicOperations::hasAtomic8() { return true; }
+
+inline bool js::jit::AtomicOperations::isLockfree8() {
+  MOZ_ASSERT(__atomic_always_lock_free(sizeof(int8_t), 0));
+  MOZ_ASSERT(__atomic_always_lock_free(sizeof(int16_t), 0));
+  MOZ_ASSERT(__atomic_always_lock_free(sizeof(int32_t), 0));
+#if defined(JS_64BIT)
+  MOZ_ASSERT(__atomic_always_lock_free(sizeof(int64_t), 0));
+#endif
+  return true;
+}
+
+inline void js::jit::AtomicOperations::fenceSeqCst() {
+  __atomic_thread_fence(__ATOMIC_SEQ_CST);
+}
+
+template <typename T>
+inline T js::jit::AtomicOperations::loadSeqCst(T* addr) {
+  static_assert(sizeof(T) <= sizeof(void*),
+                "atomics supported up to pointer size only");
+  T v;
+  __atomic_load(addr, &v, __ATOMIC_SEQ_CST);
+  return v;
+}
+
+namespace js {
+namespace jit {
+
+#if !defined(JS_64BIT)
+
+template <>
+inline int64_t js::jit::AtomicOperations::loadSeqCst(int64_t* addr) {
+  AddressGuard guard(addr);
+  return *addr;
+}
+
+template <>
+inline uint64_t js::jit::AtomicOperations::loadSeqCst(uint64_t* addr) {
+  AddressGuard guard(addr);
+  return *addr;
+}
+
+#endif
+
+}  // namespace jit
+}  // namespace js
+
+template <typename T>
+inline void js::jit::AtomicOperations::storeSeqCst(T* addr, T val) {
+  static_assert(sizeof(T) <= sizeof(void*),
+                "atomics supported up to pointer size only");
+  __atomic_store(addr, &val, __ATOMIC_SEQ_CST);
+}
+
+namespace js {
+namespace jit {
+
+#if !defined(JS_64BIT)
+
+template <>
+inline void js::jit::AtomicOperations::storeSeqCst(int64_t* addr, int64_t val) {
+  AddressGuard guard(addr);
+  *addr = val;
+}
+
+template <>
+inline void js::jit::AtomicOperations::storeSeqCst(uint64_t* addr,
+                                                   uint64_t val) {
+  AddressGuard guard(addr);
+  *addr = val;
+}
+
+#endif
+
+}  // namespace jit
+}  // namespace js
+
+template <typename T>
+inline T js::jit::AtomicOperations::compareExchangeSeqCst(T* addr, T oldval,
+                                                          T newval) {
+  static_assert(sizeof(T) <= sizeof(void*),
+                "atomics supported up to pointer size only");
+  __atomic_compare_exchange(addr, &oldval, &newval, false, __ATOMIC_SEQ_CST,
+                            __ATOMIC_SEQ_CST);
+  return oldval;
+}
+
+namespace js {
+namespace jit {
+
+#if !defined(JS_64BIT)
+
+template <>
+inline int64_t js::jit::AtomicOperations::compareExchangeSeqCst(
+    int64_t* addr, int64_t oldval, int64_t newval) {
+  AddressGuard guard(addr);
+  int64_t val = *addr;
+  if (val == oldval) {
+    *addr = newval;
+  }
+  return val;
+}
+
+template <>
+inline uint64_t js::jit::AtomicOperations::compareExchangeSeqCst(
+    uint64_t* addr, uint64_t oldval, uint64_t newval) {
+  AddressGuard guard(addr);
+  uint64_t val = *addr;
+  if (val == oldval) {
+    *addr = newval;
+  }
+  return val;
+}
+
+#endif
+
+}  // namespace jit
+}  // namespace js
+
+template <typename T>
+inline T js::jit::AtomicOperations::fetchAddSeqCst(T* addr, T val) {
+  static_assert(sizeof(T) <= sizeof(void*),
+                "atomics supported up to pointer size only");
+  return __atomic_fetch_add(addr, val, __ATOMIC_SEQ_CST);
+}
+
+namespace js {
+namespace jit {
+
+#if !defined(JS_64BIT)
+
+template <>
+inline int64_t js::jit::AtomicOperations::fetchAddSeqCst(int64_t* addr,
+                                                         int64_t val) {
+  AddressGuard guard(addr);
+  int64_t old = *addr;
+  *addr = old + val;
+  return old;
+}
+
+template <>
+inline uint64_t js::jit::AtomicOperations::fetchAddSeqCst(uint64_t* addr,
+                                                          uint64_t val) {
+  AddressGuard guard(addr);
+  uint64_t old = *addr;
+  *addr = old + val;
+  return old;
+}
+
+#endif
+
+}  // namespace jit
+}  // namespace js
+
+template <typename T>
+inline T js::jit::AtomicOperations::fetchSubSeqCst(T* addr, T val) {
+  static_assert(sizeof(T) <= sizeof(void*),
+                "atomics supported up to pointer size only");
+  return __atomic_fetch_sub(addr, val, __ATOMIC_SEQ_CST);
+}
+
+namespace js {
+namespace jit {
+
+#if !defined(JS_64BIT)
+
+template <>
+inline int64_t js::jit::AtomicOperations::fetchSubSeqCst(int64_t* addr,
+                                                         int64_t val) {
+  AddressGuard guard(addr);
+  int64_t old = *addr;
+  *addr = old - val;
+  return old;
+}
+
+template <>
+inline uint64_t js::jit::AtomicOperations::fetchSubSeqCst(uint64_t* addr,
+                                                          uint64_t val) {
+  AddressGuard guard(addr);
+  uint64_t old = *addr;
+  *addr = old - val;
+  return old;
+}
+
+#endif
+
+}  // namespace jit
+}  // namespace js
+
+template <typename T>
+inline T js::jit::AtomicOperations::fetchAndSeqCst(T* addr, T val) {
+  static_assert(sizeof(T) <= sizeof(void*),
+                "atomics supported up to pointer size only");
+  return __atomic_fetch_and(addr, val, __ATOMIC_SEQ_CST);
+}
+
+namespace js {
+namespace jit {
+
+#if !defined(JS_64BIT)
+
+template <>
+inline int64_t js::jit::AtomicOperations::fetchAndSeqCst(int64_t* addr,
+                                                         int64_t val) {
+  AddressGuard guard(addr);
+  int64_t old = *addr;
+  *addr = old & val;
+  return old;
+}
+
+template <>
+inline uint64_t js::jit::AtomicOperations::fetchAndSeqCst(uint64_t* addr,
+                                                          uint64_t val) {
+  AddressGuard guard(addr);
+  uint64_t old = *addr;
+  *addr = old & val;
+  return old;
+}
+
+#endif
+
+}  // namespace jit
+}  // namespace js
+
+template <typename T>
+inline T js::jit::AtomicOperations::fetchOrSeqCst(T* addr, T val) {
+  static_assert(sizeof(T) <= sizeof(void*),
+                "atomics supported up to pointer size only");
+  return __atomic_fetch_or(addr, val, __ATOMIC_SEQ_CST);
+}
+
+namespace js {
+namespace jit {
+
+#if !defined(JS_64BIT)
+
+template <>
+inline int64_t js::jit::AtomicOperations::fetchOrSeqCst(int64_t* addr,
+                                                        int64_t val) {
+  AddressGuard guard(addr);
+  int64_t old = *addr;
+  *addr = old | val;
+  return old;
+}
+
+template <>
+inline uint64_t js::jit::AtomicOperations::fetchOrSeqCst(uint64_t* addr,
+                                                         uint64_t val) {
+  AddressGuard guard(addr);
+  uint64_t old = *addr;
+  *addr = old | val;
+  return old;
+}
+
+#endif
+
+}  // namespace jit
+}  // namespace js
+
+template <typename T>
+inline T js::jit::AtomicOperations::fetchXorSeqCst(T* addr, T val) {
+  static_assert(sizeof(T) <= sizeof(void*),
+                "atomics supported up to pointer size only");
+  return __atomic_fetch_xor(addr, val, __ATOMIC_SEQ_CST);
+}
+
+namespace js {
+namespace jit {
+
+#if !defined(JS_64BIT)
+
+template <>
+inline int64_t js::jit::AtomicOperations::fetchXorSeqCst(int64_t* addr,
+                                                         int64_t val) {
+  AddressGuard guard(addr);
+  int64_t old = *addr;
+  *addr = old ^ val;
+  return old;
+}
+
+template <>
+inline uint64_t js::jit::AtomicOperations::fetchXorSeqCst(uint64_t* addr,
+                                                          uint64_t val) {
+  AddressGuard guard(addr);
+  uint64_t old = *addr;
+  *addr = old ^ val;
+  return old;
+}
+
+#endif
+
+}  // namespace jit
+}  // namespace js
+
+template <typename T>
+inline T js::jit::AtomicOperations::loadSafeWhenRacy(T* addr) {
+  static_assert(sizeof(T) <= sizeof(void*),
+                "atomics supported up to pointer size only");
+  T v;
+  __atomic_load(addr, &v, __ATOMIC_RELAXED);
+  return v;
+}
+
+namespace js {
+namespace jit {
+
+#if !defined(JS_64BIT)
+
+template <>
+inline int64_t js::jit::AtomicOperations::loadSafeWhenRacy(int64_t* addr) {
+  return *addr;
+}
+
+template <>
+inline uint64_t js::jit::AtomicOperations::loadSafeWhenRacy(uint64_t* addr) {
+  return *addr;
+}
+
+#endif
+
+template <>
+inline uint8_clamped js::jit::AtomicOperations::loadSafeWhenRacy(
+    uint8_clamped* addr) {
+  uint8_t v;
+  __atomic_load(&addr->val, &v, __ATOMIC_RELAXED);
+  return uint8_clamped(v);
+}
+
+template <>
+inline float js::jit::AtomicOperations::loadSafeWhenRacy(float* addr) {
+  return *addr;
+}
+
+template <>
+inline double js::jit::AtomicOperations::loadSafeWhenRacy(double* addr) {
+  return *addr;
+}
+
+}  // namespace jit
+}  // namespace js
+
+template <typename T>
+inline void js::jit::AtomicOperations::storeSafeWhenRacy(T* addr, T val) {
+  static_assert(sizeof(T) <= sizeof(void*),
+                "atomics supported up to pointer size only");
+  __atomic_store(addr, &val, __ATOMIC_RELAXED);
+}
+
+namespace js {
+namespace jit {
+
+#if !defined(JS_64BIT)
+
+template <>
+inline void js::jit::AtomicOperations::storeSafeWhenRacy(int64_t* addr,
+                                                         int64_t val) {
+  *addr = val;
+}
+
+template <>
+inline void js::jit::AtomicOperations::storeSafeWhenRacy(uint64_t* addr,
+                                                         uint64_t val) {
+  *addr = val;
+}
+
+#endif
+
+template <>
+inline void js::jit::AtomicOperations::storeSafeWhenRacy(uint8_clamped* addr,
+                                                         uint8_clamped val) {
+  __atomic_store(&addr->val, &val.val, __ATOMIC_RELAXED);
+}
+
+template <>
+inline void js::jit::AtomicOperations::storeSafeWhenRacy(float* addr,
+                                                         float val) {
+  *addr = val;
+}
+
+template <>
+inline void js::jit::AtomicOperations::storeSafeWhenRacy(double* addr,
+                                                         double val) {
+  *addr = val;
+}
+
+}  // namespace jit
+}  // namespace js
+
+inline void js::jit::AtomicOperations::memcpySafeWhenRacy(void* dest,
+                                                          const void* src,
+                                                          size_t nbytes) {
+  MOZ_ASSERT(!((char*)dest <= (char*)src && (char*)src < (char*)dest + nbytes));
+  MOZ_ASSERT(!((char*)src <= (char*)dest && (char*)dest < (char*)src + nbytes));
+  ::memcpy(dest, src, nbytes);
+}
+
+inline void js::jit::AtomicOperations::memmoveSafeWhenRacy(void* dest,
+                                                           const void* src,
+                                                           size_t nbytes) {
+  ::memmove(dest, src, nbytes);
+}
+
+template <typename T>
+inline T js::jit::AtomicOperations::exchangeSeqCst(T* addr, T val) {
+  static_assert(sizeof(T) <= sizeof(void*),
+                "atomics supported up to pointer size only");
+  T v;
+  __atomic_exchange(addr, &val, &v, __ATOMIC_SEQ_CST);
+  return v;
+}
+
+namespace js {
+namespace jit {
+
+#if !defined(JS_64BIT)
+
+template <>
+inline int64_t js::jit::AtomicOperations::exchangeSeqCst(int64_t* addr,
+                                                         int64_t val) {
+  AddressGuard guard(addr);
+  int64_t old = *addr;
+  *addr = val;
+  return old;
+}
+
+template <>
+inline uint64_t js::jit::AtomicOperations::exchangeSeqCst(uint64_t* addr,
+                                                          uint64_t val) {
+  AddressGuard guard(addr);
+  uint64_t old = *addr;
+  *addr = val;
+  return old;
+}
+
+#endif
+
+}  // namespace jit
+}  // namespace js
+
+#if !defined(JS_64BIT)
+
+inline void js::jit::AddressLock::acquire() {
+  uint32_t zero = 0;
+  uint32_t one = 1;
+  while (!__atomic_compare_exchange(&spinlock, &zero, &one, true,
+                                    __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST)) {
+    zero = 0;
+  }
+}
+
+inline void js::jit::AddressLock::release() {
+  uint32_t zero = 0;
+  __atomic_store(&spinlock, &zero, __ATOMIC_SEQ_CST);
+}
+
+#endif
+
+#endif  // jit_mips_shared_AtomicOperations_mips_shared_h