Add m-esr52 at 52.6.0

1 files changed, 206 insertions, 0 deletions

diff --git a/js/public/ProfilingFrameIterator.h b/js/public/ProfilingFrameIterator.h
new file mode 100644
index 0000000000..52621adb46
--- /dev/null
+++ b/js/public/ProfilingFrameIterator.h
@@ -0,0 +1,206 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=8 sts=4 et sw=4 tw=99:
+ * 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/. */
+
+#ifndef js_ProfilingFrameIterator_h
+#define js_ProfilingFrameIterator_h
+
+#include "mozilla/Alignment.h"
+#include "mozilla/Maybe.h"
+
+#include "jsbytecode.h"
+#include "js/GCAPI.h"
+#include "js/TypeDecls.h"
+#include "js/Utility.h"
+
+struct JSContext;
+struct JSRuntime;
+class JSScript;
+
+namespace js {
+    class Activation;
+    namespace jit {
+        class JitActivation;
+        class JitProfilingFrameIterator;
+        class JitcodeGlobalEntry;
+    } // namespace jit
+    namespace wasm {
+        class ProfilingFrameIterator;
+    } // namespace wasm
+} // namespace js
+
+namespace JS {
+
+struct ForEachTrackedOptimizationAttemptOp;
+struct ForEachTrackedOptimizationTypeInfoOp;
+
+// This iterator can be used to walk the stack of a thread suspended at an
+// arbitrary pc. To provide acurate results, profiling must have been enabled
+// (via EnableRuntimeProfilingStack) before executing the callstack being
+// unwound.
+//
+// Note that the caller must not do anything that could cause GC to happen while
+// the iterator is alive, since this could invalidate Ion code and cause its
+// contents to become out of date.
+class JS_PUBLIC_API(ProfilingFrameIterator)
+{
+    JSRuntime* rt_;
+    uint32_t sampleBufferGen_;
+    js::Activation* activation_;
+
+    // When moving past a JitActivation, we need to save the prevJitTop
+    // from it to use as the exit-frame pointer when the next caller jit
+    // activation (if any) comes around.
+    void* savedPrevJitTop_;
+
+    JS::AutoCheckCannotGC nogc_;
+
+    static const unsigned StorageSpace = 8 * sizeof(void*);
+    mozilla::AlignedStorage<StorageSpace> storage_;
+    js::wasm::ProfilingFrameIterator& wasmIter() {
+        MOZ_ASSERT(!done());
+        MOZ_ASSERT(isWasm());
+        return *reinterpret_cast<js::wasm::ProfilingFrameIterator*>(storage_.addr());
+    }
+    const js::wasm::ProfilingFrameIterator& wasmIter() const {
+        MOZ_ASSERT(!done());
+        MOZ_ASSERT(isWasm());
+        return *reinterpret_cast<const js::wasm::ProfilingFrameIterator*>(storage_.addr());
+    }
+
+    js::jit::JitProfilingFrameIterator& jitIter() {
+        MOZ_ASSERT(!done());
+        MOZ_ASSERT(isJit());
+        return *reinterpret_cast<js::jit::JitProfilingFrameIterator*>(storage_.addr());
+    }
+
+    const js::jit::JitProfilingFrameIterator& jitIter() const {
+        MOZ_ASSERT(!done());
+        MOZ_ASSERT(isJit());
+        return *reinterpret_cast<const js::jit::JitProfilingFrameIterator*>(storage_.addr());
+    }
+
+    void settle();
+
+    bool hasSampleBufferGen() const {
+        return sampleBufferGen_ != UINT32_MAX;
+    }
+
+  public:
+    struct RegisterState
+    {
+        RegisterState() : pc(nullptr), sp(nullptr), lr(nullptr) {}
+        void* pc;
+        void* sp;
+        void* lr;
+    };
+
+    ProfilingFrameIterator(JSContext* cx, const RegisterState& state,
+                           uint32_t sampleBufferGen = UINT32_MAX);
+    ~ProfilingFrameIterator();
+    void operator++();
+    bool done() const { return !activation_; }
+
+    // Assuming the stack grows down (we do), the return value:
+    //  - always points into the stack
+    //  - is weakly monotonically increasing (may be equal for successive frames)
+    //  - will compare greater than newer native and psuedo-stack frame addresses
+    //    and less than older native and psuedo-stack frame addresses
+    void* stackAddress() const;
+
+    enum FrameKind
+    {
+      Frame_Baseline,
+      Frame_Ion,
+      Frame_Wasm
+    };
+
+    struct Frame
+    {
+        FrameKind kind;
+        void* stackAddress;
+        void* returnAddress;
+        void* activation;
+        UniqueChars label;
+    };
+
+    bool isWasm() const;
+    bool isJit() const;
+
+    uint32_t extractStack(Frame* frames, uint32_t offset, uint32_t end) const;
+
+    mozilla::Maybe<Frame> getPhysicalFrameWithoutLabel() const;
+
+  private:
+    mozilla::Maybe<Frame> getPhysicalFrameAndEntry(js::jit::JitcodeGlobalEntry* entry) const;
+
+    void iteratorConstruct(const RegisterState& state);
+    void iteratorConstruct();
+    void iteratorDestroy();
+    bool iteratorDone();
+};
+
+JS_FRIEND_API(bool)
+IsProfilingEnabledForContext(JSContext* cx);
+
+/**
+ * After each sample run, this method should be called with the latest sample
+ * buffer generation, and the lapCount.  It will update corresponding fields on
+ * JSRuntime.
+ *
+ * See fields |profilerSampleBufferGen|, |profilerSampleBufferLapCount| on
+ * JSRuntime for documentation about what these values are used for.
+ */
+JS_FRIEND_API(void)
+UpdateJSContextProfilerSampleBufferGen(JSContext* cx, uint32_t generation,
+                                       uint32_t lapCount);
+
+struct ForEachProfiledFrameOp
+{
+    // A handle to the underlying JitcodeGlobalEntry, so as to avoid repeated
+    // lookups on JitcodeGlobalTable.
+    class MOZ_STACK_CLASS FrameHandle
+    {
+        friend JS_PUBLIC_API(void) ForEachProfiledFrame(JSContext* cx, void* addr,
+                                                        ForEachProfiledFrameOp& op);
+
+        JSRuntime* rt_;
+        js::jit::JitcodeGlobalEntry& entry_;
+        void* addr_;
+        void* canonicalAddr_;
+        const char* label_;
+        uint32_t depth_;
+        mozilla::Maybe<uint8_t> optsIndex_;
+
+        FrameHandle(JSRuntime* rt, js::jit::JitcodeGlobalEntry& entry, void* addr,
+                    const char* label, uint32_t depth);
+
+        void updateHasTrackedOptimizations();
+
+      public:
+        const char* label() const { return label_; }
+        uint32_t depth() const { return depth_; }
+        bool hasTrackedOptimizations() const { return optsIndex_.isSome(); }
+        void* canonicalAddress() const { return canonicalAddr_; }
+
+        JS_PUBLIC_API(ProfilingFrameIterator::FrameKind) frameKind() const;
+        JS_PUBLIC_API(void) forEachOptimizationAttempt(ForEachTrackedOptimizationAttemptOp& op,
+                                                       JSScript** scriptOut,
+                                                       jsbytecode** pcOut) const;
+
+        JS_PUBLIC_API(void)
+        forEachOptimizationTypeInfo(ForEachTrackedOptimizationTypeInfoOp& op) const;
+    };
+
+    // Called once per frame.
+    virtual void operator()(const FrameHandle& frame) = 0;
+};
+
+JS_PUBLIC_API(void)
+ForEachProfiledFrame(JSContext* cx, void* addr, ForEachProfiledFrameOp& op);
+
+} // namespace JS
+
+#endif  /* js_ProfilingFrameIterator_h */