1 files changed, 127 insertions, 0 deletions
diff --git a/js/src/jit/arm/Bailouts-arm.cpp b/js/src/jit/arm/Bailouts-arm.cpp
new file mode 100644
index 0000000000..b13dd5e3b3
--- /dev/null
+++ b/js/src/jit/arm/Bailouts-arm.cpp
@@ -0,0 +1,127 @@
+/* -*- 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/. */
+
+#include "jit/arm/Assembler-arm.h"
+#include "jit/Bailouts.h"
+#include "jit/JitFrames.h"
+#include "jit/JitRuntime.h"
+#include "jit/SafepointIndex.h"
+#include "jit/ScriptFromCalleeToken.h"
+#include "vm/JSContext.h"
+#include "vm/Realm.h"
+
+#include "vm/JSScript-inl.h"
+
+using namespace js;
+using namespace js::jit;
+
+namespace js {
+namespace jit {
+
+class BailoutStack {
+  uintptr_t frameClassId_;
+  // This is pushed in the bailout handler. Both entry points into the handler
+  // inserts their own value int lr, which is then placed onto the stack along
+  // with frameClassId_ above. This should be migrated to ip.
+ public:
+  union {
+    uintptr_t frameSize_;
+    uintptr_t tableOffset_;
+  };
+
+ protected:  // Silence Clang warning about unused private fields.
+  RegisterDump::FPUArray fpregs_;
+  RegisterDump::GPRArray regs_;
+
+  uintptr_t snapshotOffset_;
+  uintptr_t padding_;
+
+ public:
+  FrameSizeClass frameClass() const {
+    return FrameSizeClass::FromClass(frameClassId_);
+  }
+  uintptr_t tableOffset() const {
+    MOZ_ASSERT(frameClass() != FrameSizeClass::None());
+    return tableOffset_;
+  }
+  uint32_t frameSize() const {
+    if (frameClass() == FrameSizeClass::None()) {
+      return frameSize_;
+    }
+    return frameClass().frameSize();
+  }
+  MachineState machine() { return MachineState::FromBailout(regs_, fpregs_); }
+  SnapshotOffset snapshotOffset() const {
+    MOZ_ASSERT(frameClass() == FrameSizeClass::None());
+    return snapshotOffset_;
+  }
+  uint8_t* parentStackPointer() const {
+    if (frameClass() == FrameSizeClass::None()) {
+      return (uint8_t*)this + sizeof(BailoutStack);
+    }
+    return (uint8_t*)this + offsetof(BailoutStack, snapshotOffset_);
+  }
+};
+
+// Make sure the compiler doesn't add extra padding.
+static_assert((sizeof(BailoutStack) % 8) == 0,
+              "BailoutStack should be 8-byte aligned.");
+
+}  // namespace jit
+}  // namespace js
+
+BailoutFrameInfo::BailoutFrameInfo(const JitActivationIterator& activations,
+                                   BailoutStack* bailout)
+    : machine_(bailout->machine()) {
+  uint8_t* sp = bailout->parentStackPointer();
+  framePointer_ = sp + bailout->frameSize();
+  topFrameSize_ = framePointer_ - sp;
+
+  JSScript* script =
+      ScriptFromCalleeToken(((JitFrameLayout*)framePointer_)->calleeToken());
+  JitActivation* activation = activations.activation()->asJit();
+  topIonScript_ = script->ionScript();
+
+  attachOnJitActivation(activations);
+
+  if (bailout->frameClass() == FrameSizeClass::None()) {
+    snapshotOffset_ = bailout->snapshotOffset();
+    return;
+  }
+
+  // Compute the snapshot offset from the bailout ID.
+  JSRuntime* rt = activation->compartment()->runtimeFromMainThread();
+  TrampolinePtr code = rt->jitRuntime()->getBailoutTable(bailout->frameClass());
+#ifdef DEBUG
+  uint32_t tableSize =
+      rt->jitRuntime()->getBailoutTableSize(bailout->frameClass());
+#endif
+  uintptr_t tableOffset = bailout->tableOffset();
+  uintptr_t tableStart =
+      reinterpret_cast<uintptr_t>(Assembler::BailoutTableStart(code.value));
+
+  MOZ_ASSERT(tableOffset >= tableStart && tableOffset < tableStart + tableSize);
+  MOZ_ASSERT((tableOffset - tableStart) % BAILOUT_TABLE_ENTRY_SIZE == 0);
+
+  uint32_t bailoutId =
+      ((tableOffset - tableStart) / BAILOUT_TABLE_ENTRY_SIZE) - 1;
+  MOZ_ASSERT(bailoutId < BAILOUT_TABLE_SIZE);
+
+  snapshotOffset_ = topIonScript_->bailoutToSnapshot(bailoutId);
+}
+
+BailoutFrameInfo::BailoutFrameInfo(const JitActivationIterator& activations,
+                                   InvalidationBailoutStack* bailout)
+    : machine_(bailout->machine()) {
+  framePointer_ = (uint8_t*)bailout->fp();
+  topFrameSize_ = framePointer_ - bailout->sp();
+  topIonScript_ = bailout->ionScript();
+  attachOnJitActivation(activations);
+
+  uint8_t* returnAddressToFp_ = bailout->osiPointReturnAddress();
+  const OsiIndex* osiIndex = topIonScript_->getOsiIndex(returnAddressToFp_);
+  snapshotOffset_ = osiIndex->snapshotOffset();
+}