1 files changed, 561 insertions, 0 deletions

diff --git a/js/src/vm/GeckoProfiler.cpp b/js/src/vm/GeckoProfiler.cpp
new file mode 100644
index 0000000000..41c13232df
--- /dev/null
+++ b/js/src/vm/GeckoProfiler.cpp
@@ -0,0 +1,561 @@
+/* -*- 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 "vm/GeckoProfiler-inl.h"
+
+#include "mozilla/Sprintf.h"
+
+#include "gc/GC.h"
+#include "gc/PublicIterators.h"
+#include "jit/BaselineJIT.h"
+#include "jit/JitcodeMap.h"
+#include "jit/JitRuntime.h"
+#include "jit/JSJitFrameIter.h"
+#include "jit/PerfSpewer.h"
+#include "js/ProfilingStack.h"
+#include "vm/FrameIter.h"  // js::OnlyJSJitFrameIter
+#include "vm/JitActivation.h"
+#include "vm/JSScript.h"
+
+#include "gc/Marking-inl.h"
+#include "jit/JSJitFrameIter-inl.h"
+
+using namespace js;
+
+GeckoProfilerThread::GeckoProfilerThread()
+    : profilingStack_(nullptr), profilingStackIfEnabled_(nullptr) {}
+
+GeckoProfilerRuntime::GeckoProfilerRuntime(JSRuntime* rt)
+    : rt(rt),
+      strings_(),
+      slowAssertions(false),
+      enabled_(false),
+      eventMarker_(nullptr) {
+  MOZ_ASSERT(rt != nullptr);
+}
+
+void GeckoProfilerThread::setProfilingStack(ProfilingStack* profilingStack,
+                                            bool enabled) {
+  profilingStack_ = profilingStack;
+  profilingStackIfEnabled_ = enabled ? profilingStack : nullptr;
+}
+
+void GeckoProfilerRuntime::setEventMarker(void (*fn)(const char*,
+                                                     const char*)) {
+  eventMarker_ = fn;
+}
+
+// Get a pointer to the top-most profiling frame, given the exit frame pointer.
+static jit::JitFrameLayout* GetTopProfilingJitFrame(jit::JitActivation* act) {
+  // If there is no exit frame set, just return.
+  if (!act->hasExitFP()) {
+    return nullptr;
+  }
+
+  // Skip wasm frames that might be in the way.
+  OnlyJSJitFrameIter iter(act);
+  if (iter.done()) {
+    return nullptr;
+  }
+
+  jit::JSJitProfilingFrameIterator jitIter(
+      (jit::CommonFrameLayout*)iter.frame().fp());
+  MOZ_ASSERT(!jitIter.done());
+  return jitIter.framePtr();
+}
+
+void GeckoProfilerRuntime::enable(bool enabled) {
+  JSContext* cx = rt->mainContextFromAnyThread();
+  MOZ_ASSERT(cx->geckoProfiler().infraInstalled());
+
+  if (enabled_ == enabled) {
+    return;
+  }
+
+  /*
+   * Ensure all future generated code will be instrumented, or that all
+   * currently instrumented code is discarded
+   */
+  ReleaseAllJITCode(rt->gcContext());
+
+  // This function is called when the Gecko profiler makes a new Sampler
+  // (and thus, a new circular buffer). Set all current entries in the
+  // JitcodeGlobalTable as expired and reset the buffer range start.
+  if (rt->hasJitRuntime() && rt->jitRuntime()->hasJitcodeGlobalTable()) {
+    rt->jitRuntime()->getJitcodeGlobalTable()->setAllEntriesAsExpired();
+  }
+  rt->setProfilerSampleBufferRangeStart(0);
+
+  // Ensure that lastProfilingFrame is null for the main thread.
+  if (cx->jitActivation) {
+    cx->jitActivation->setLastProfilingFrame(nullptr);
+    cx->jitActivation->setLastProfilingCallSite(nullptr);
+  }
+
+  enabled_ = enabled;
+
+  /* Toggle Gecko Profiler-related jumps on baseline jitcode.
+   * The call to |ReleaseAllJITCode| above will release most baseline jitcode,
+   * but not jitcode for scripts with active frames on the stack.  These scripts
+   * need to have their profiler state toggled so they behave properly.
+   */
+  jit::ToggleBaselineProfiling(cx, enabled);
+
+  // Update lastProfilingFrame to point to the top-most JS jit-frame currently
+  // on stack.
+  if (cx->jitActivation) {
+    // Walk through all activations, and set their lastProfilingFrame
+    // appropriately.
+    if (enabled) {
+      jit::JitActivation* jitActivation = cx->jitActivation;
+      while (jitActivation) {
+        auto* lastProfilingFrame = GetTopProfilingJitFrame(jitActivation);
+        jitActivation->setLastProfilingFrame(lastProfilingFrame);
+        jitActivation->setLastProfilingCallSite(nullptr);
+        jitActivation = jitActivation->prevJitActivation();
+      }
+    } else {
+      jit::JitActivation* jitActivation = cx->jitActivation;
+      while (jitActivation) {
+        jitActivation->setLastProfilingFrame(nullptr);
+        jitActivation->setLastProfilingCallSite(nullptr);
+        jitActivation = jitActivation->prevJitActivation();
+      }
+    }
+  }
+
+  // WebAssembly code does not need to be released, but profiling string
+  // labels have to be generated so that they are available during async
+  // profiling stack iteration.
+  for (RealmsIter r(rt); !r.done(); r.next()) {
+    r->wasm.ensureProfilingLabels(enabled);
+  }
+
+#ifdef JS_STRUCTURED_SPEW
+  // Enable the structured spewer if the environment variable is set.
+  if (enabled) {
+    cx->spewer().enableSpewing();
+  } else {
+    cx->spewer().disableSpewing();
+  }
+#endif
+}
+
+/* Lookup the string for the function/script, creating one if necessary */
+const char* GeckoProfilerRuntime::profileString(JSContext* cx,
+                                                BaseScript* script) {
+  ProfileStringMap::AddPtr s = strings().lookupForAdd(script);
+
+  if (!s) {
+    UniqueChars str = allocProfileString(cx, script);
+    if (!str) {
+      return nullptr;
+    }
+    MOZ_ASSERT(script->hasBytecode());
+    if (!strings().add(s, script, std::move(str))) {
+      ReportOutOfMemory(cx);
+      return nullptr;
+    }
+  }
+
+  return s->value().get();
+}
+
+void GeckoProfilerRuntime::onScriptFinalized(BaseScript* script) {
+  /*
+   * This function is called whenever a script is destroyed, regardless of
+   * whether profiling has been turned on, so don't invoke a function on an
+   * invalid hash set. Also, even if profiling was enabled but then turned
+   * off, we still want to remove the string, so no check of enabled() is
+   * done.
+   */
+  if (ProfileStringMap::Ptr entry = strings().lookup(script)) {
+    strings().remove(entry);
+  }
+}
+
+void GeckoProfilerRuntime::markEvent(const char* event, const char* details) {
+  MOZ_ASSERT(enabled());
+  if (eventMarker_) {
+    JS::AutoSuppressGCAnalysis nogc;
+    eventMarker_(event, details);
+  }
+}
+
+bool GeckoProfilerThread::enter(JSContext* cx, JSScript* script) {
+  const char* dynamicString =
+      cx->runtime()->geckoProfiler().profileString(cx, script);
+  if (dynamicString == nullptr) {
+    return false;
+  }
+
+#ifdef DEBUG
+  // In debug builds, assert the JS profiling stack frames already on the
+  // stack have a non-null pc. Only look at the top frames to avoid quadratic
+  // behavior.
+  uint32_t sp = profilingStack_->stackPointer;
+  if (sp > 0 && sp - 1 < profilingStack_->stackCapacity()) {
+    size_t start = (sp > 4) ? sp - 4 : 0;
+    for (size_t i = start; i < sp - 1; i++) {
+      MOZ_ASSERT_IF(profilingStack_->frames[i].isJsFrame(),
+                    profilingStack_->frames[i].pc());
+    }
+  }
+#endif
+
+  profilingStack_->pushJsFrame(
+      "", dynamicString, script, script->code(),
+      script->realm()->creationOptions().profilerRealmID());
+  return true;
+}
+
+void GeckoProfilerThread::exit(JSContext* cx, JSScript* script) {
+  profilingStack_->pop();
+
+#ifdef DEBUG
+  /* Sanity check to make sure push/pop balanced */
+  uint32_t sp = profilingStack_->stackPointer;
+  if (sp < profilingStack_->stackCapacity()) {
+    JSRuntime* rt = script->runtimeFromMainThread();
+    const char* dynamicString = rt->geckoProfiler().profileString(cx, script);
+    /* Can't fail lookup because we should already be in the set */
+    MOZ_ASSERT(dynamicString);
+
+    // Bug 822041
+    if (!profilingStack_->frames[sp].isJsFrame()) {
+      fprintf(stderr, "--- ABOUT TO FAIL ASSERTION ---\n");
+      fprintf(stderr, " frames=%p size=%u/%u\n", (void*)profilingStack_->frames,
+              uint32_t(profilingStack_->stackPointer),
+              profilingStack_->stackCapacity());
+      for (int32_t i = sp; i >= 0; i--) {
+        ProfilingStackFrame& frame = profilingStack_->frames[i];
+        if (frame.isJsFrame()) {
+          fprintf(stderr, "  [%d] JS %s\n", i, frame.dynamicString());
+        } else {
+          fprintf(stderr, "  [%d] Label %s\n", i, frame.dynamicString());
+        }
+      }
+    }
+
+    ProfilingStackFrame& frame = profilingStack_->frames[sp];
+    MOZ_ASSERT(frame.isJsFrame());
+    MOZ_ASSERT(frame.script() == script);
+    MOZ_ASSERT(strcmp((const char*)frame.dynamicString(), dynamicString) == 0);
+  }
+#endif
+}
+
+/*
+ * Serializes the script/function pair into a "descriptive string" which is
+ * allowed to fail. This function cannot trigger a GC because it could finalize
+ * some scripts, resize the hash table of profile strings, and invalidate the
+ * AddPtr held while invoking allocProfileString.
+ */
+/* static */
+UniqueChars GeckoProfilerRuntime::allocProfileString(JSContext* cx,
+                                                     BaseScript* script) {
+  // Note: this profiler string is regexp-matched by
+  // devtools/client/profiler/cleopatra/js/parserWorker.js.
+
+  // If the script has a function, try calculating its name.
+  bool hasName = false;
+  size_t nameLength = 0;
+  UniqueChars nameStr;
+  JSFunction* func = script->function();
+  if (func && func->displayAtom()) {
+    nameStr = StringToNewUTF8CharsZ(cx, *func->displayAtom());
+    if (!nameStr) {
+      return nullptr;
+    }
+
+    nameLength = strlen(nameStr.get());
+    hasName = true;
+  }
+
+  // Calculate filename length. We cap this to a reasonable limit to avoid
+  // performance impact of strlen/alloc/memcpy.
+  constexpr size_t MaxFilenameLength = 200;
+  const char* filenameStr = script->filename() ? script->filename() : "(null)";
+  size_t filenameLength = js_strnlen(filenameStr, MaxFilenameLength);
+
+  // Calculate line + column length.
+  bool hasLineAndColumn = false;
+  size_t lineAndColumnLength = 0;
+  char lineAndColumnStr[30];
+  if (hasName || script->isFunction() || script->isForEval()) {
+    lineAndColumnLength = SprintfLiteral(lineAndColumnStr, "%u:%u",
+                                         script->lineno(), script->column());
+    hasLineAndColumn = true;
+  }
+
+  // Full profile string for scripts with functions is:
+  //      FuncName (FileName:Lineno:Column)
+  // Full profile string for scripts without functions is:
+  //      FileName:Lineno:Column
+  // Full profile string for scripts without functions and without lines is:
+  //      FileName
+
+  // Calculate full string length.
+  size_t fullLength = 0;
+  if (hasName) {
+    MOZ_ASSERT(hasLineAndColumn);
+    fullLength = nameLength + 2 + filenameLength + 1 + lineAndColumnLength + 1;
+  } else if (hasLineAndColumn) {
+    fullLength = filenameLength + 1 + lineAndColumnLength;
+  } else {
+    fullLength = filenameLength;
+  }
+
+  // Allocate string.
+  UniqueChars str(cx->pod_malloc<char>(fullLength + 1));
+  if (!str) {
+    return nullptr;
+  }
+
+  size_t cur = 0;
+
+  // Fill string with function name if needed.
+  if (hasName) {
+    memcpy(str.get() + cur, nameStr.get(), nameLength);
+    cur += nameLength;
+    str[cur++] = ' ';
+    str[cur++] = '(';
+  }
+
+  // Fill string with filename chars.
+  memcpy(str.get() + cur, filenameStr, filenameLength);
+  cur += filenameLength;
+
+  // Fill line + column chars.
+  if (hasLineAndColumn) {
+    str[cur++] = ':';
+    memcpy(str.get() + cur, lineAndColumnStr, lineAndColumnLength);
+    cur += lineAndColumnLength;
+  }
+
+  // Terminal ')' if necessary.
+  if (hasName) {
+    str[cur++] = ')';
+  }
+
+  MOZ_ASSERT(cur == fullLength);
+  str[cur] = 0;
+
+  return str;
+}
+
+void GeckoProfilerThread::trace(JSTracer* trc) {
+  if (profilingStack_) {
+    size_t size = profilingStack_->stackSize();
+    for (size_t i = 0; i < size; i++) {
+      profilingStack_->frames[i].trace(trc);
+    }
+  }
+}
+
+void GeckoProfilerRuntime::fixupStringsMapAfterMovingGC() {
+  for (ProfileStringMap::Enum e(strings()); !e.empty(); e.popFront()) {
+    BaseScript* script = e.front().key();
+    if (IsForwarded(script)) {
+      script = Forwarded(script);
+      e.rekeyFront(script);
+    }
+  }
+}
+
+#ifdef JSGC_HASH_TABLE_CHECKS
+void GeckoProfilerRuntime::checkStringsMapAfterMovingGC() {
+  for (auto r = strings().all(); !r.empty(); r.popFront()) {
+    BaseScript* script = r.front().key();
+    CheckGCThingAfterMovingGC(script);
+    auto ptr = strings().lookup(script);
+    MOZ_RELEASE_ASSERT(ptr.found() && &*ptr == &r.front());
+  }
+}
+#endif
+
+void ProfilingStackFrame::trace(JSTracer* trc) {
+  if (isJsFrame()) {
+    JSScript* s = rawScript();
+    TraceNullableRoot(trc, &s, "ProfilingStackFrame script");
+    spOrScript = s;
+  }
+}
+
+GeckoProfilerBaselineOSRMarker::GeckoProfilerBaselineOSRMarker(
+    JSContext* cx, bool hasProfilerFrame)
+    : profiler(&cx->geckoProfiler()) {
+  if (!hasProfilerFrame || !cx->runtime()->geckoProfiler().enabled()) {
+    profiler = nullptr;
+    return;
+  }
+
+  uint32_t sp = profiler->profilingStack_->stackPointer;
+  if (sp >= profiler->profilingStack_->stackCapacity()) {
+    profiler = nullptr;
+    return;
+  }
+
+  spBefore_ = sp;
+  if (sp == 0) {
+    return;
+  }
+
+  ProfilingStackFrame& frame = profiler->profilingStack_->frames[sp - 1];
+  MOZ_ASSERT(!frame.isOSRFrame());
+  frame.setIsOSRFrame(true);
+}
+
+GeckoProfilerBaselineOSRMarker::~GeckoProfilerBaselineOSRMarker() {
+  if (profiler == nullptr) {
+    return;
+  }
+
+  uint32_t sp = profiler->stackPointer();
+  MOZ_ASSERT(spBefore_ == sp);
+  if (sp == 0) {
+    return;
+  }
+
+  ProfilingStackFrame& frame = profiler->stack()[sp - 1];
+  MOZ_ASSERT(frame.isOSRFrame());
+  frame.setIsOSRFrame(false);
+}
+
+JS_PUBLIC_API JSScript* ProfilingStackFrame::script() const {
+  MOZ_ASSERT(isJsFrame());
+  auto* script = reinterpret_cast<JSScript*>(spOrScript.operator void*());
+  if (!script) {
+    return nullptr;
+  }
+
+  // If profiling is supressed then we can't trust the script pointers to be
+  // valid as they could be in the process of being moved by a compacting GC
+  // (although it's still OK to get the runtime from them).
+  JSContext* cx = script->runtimeFromAnyThread()->mainContextFromAnyThread();
+  if (!cx->isProfilerSamplingEnabled()) {
+    return nullptr;
+  }
+
+  MOZ_ASSERT(!IsForwarded(script));
+  return script;
+}
+
+JS_PUBLIC_API JSFunction* ProfilingStackFrame::function() const {
+  JSScript* script = this->script();
+  return script ? script->function() : nullptr;
+}
+
+JS_PUBLIC_API jsbytecode* ProfilingStackFrame::pc() const {
+  MOZ_ASSERT(isJsFrame());
+  if (pcOffsetIfJS_ == NullPCOffset) {
+    return nullptr;
+  }
+
+  JSScript* script = this->script();
+  return script ? script->offsetToPC(pcOffsetIfJS_) : nullptr;
+}
+
+/* static */
+int32_t ProfilingStackFrame::pcToOffset(JSScript* aScript, jsbytecode* aPc) {
+  return aPc ? aScript->pcToOffset(aPc) : NullPCOffset;
+}
+
+void ProfilingStackFrame::setPC(jsbytecode* pc) {
+  MOZ_ASSERT(isJsFrame());
+  JSScript* script = this->script();
+  MOZ_ASSERT(
+      script);  // This should not be called while profiling is suppressed.
+  pcOffsetIfJS_ = pcToOffset(script, pc);
+}
+
+JS_PUBLIC_API void js::SetContextProfilingStack(
+    JSContext* cx, ProfilingStack* profilingStack) {
+  cx->geckoProfiler().setProfilingStack(
+      profilingStack, cx->runtime()->geckoProfiler().enabled());
+}
+
+JS_PUBLIC_API void js::EnableContextProfilingStack(JSContext* cx,
+                                                   bool enabled) {
+  cx->geckoProfiler().enable(enabled);
+  cx->runtime()->geckoProfiler().enable(enabled);
+}
+
+JS_PUBLIC_API void js::RegisterContextProfilingEventMarker(
+    JSContext* cx, void (*fn)(const char*, const char*)) {
+  MOZ_ASSERT(cx->runtime()->geckoProfiler().enabled());
+  cx->runtime()->geckoProfiler().setEventMarker(fn);
+}
+
+AutoSuppressProfilerSampling::AutoSuppressProfilerSampling(JSContext* cx)
+    : cx_(cx), previouslyEnabled_(cx->isProfilerSamplingEnabled()) {
+  if (previouslyEnabled_) {
+    cx_->disableProfilerSampling();
+  }
+}
+
+AutoSuppressProfilerSampling::~AutoSuppressProfilerSampling() {
+  if (previouslyEnabled_) {
+    cx_->enableProfilerSampling();
+  }
+}
+
+namespace JS {
+
+// clang-format off
+
+// ProfilingSubcategory_X:
+// One enum for each category X, listing that category's subcategories. This
+// allows the sProfilingCategoryInfo macro construction below to look up a
+// per-category index for a subcategory.
+#define SUBCATEGORY_ENUMS_BEGIN_CATEGORY(name, labelAsString, color) \
+  enum class ProfilingSubcategory_##name : uint32_t {
+#define SUBCATEGORY_ENUMS_SUBCATEGORY(category, name, labelAsString) \
+    name,
+#define SUBCATEGORY_ENUMS_END_CATEGORY \
+  };
+MOZ_PROFILING_CATEGORY_LIST(SUBCATEGORY_ENUMS_BEGIN_CATEGORY,
+                            SUBCATEGORY_ENUMS_SUBCATEGORY,
+                            SUBCATEGORY_ENUMS_END_CATEGORY)
+#undef SUBCATEGORY_ENUMS_BEGIN_CATEGORY
+#undef SUBCATEGORY_ENUMS_SUBCATEGORY
+#undef SUBCATEGORY_ENUMS_END_CATEGORY
+
+// sProfilingCategoryPairInfo:
+// A list of ProfilingCategoryPairInfos with the same order as
+// ProfilingCategoryPair, which can be used to map a ProfilingCategoryPair to
+// its information.
+#define CATEGORY_INFO_BEGIN_CATEGORY(name, labelAsString, color)
+#define CATEGORY_INFO_SUBCATEGORY(category, name, labelAsString) \
+  {ProfilingCategory::category,                                  \
+   uint32_t(ProfilingSubcategory_##category::name), labelAsString},
+#define CATEGORY_INFO_END_CATEGORY
+const ProfilingCategoryPairInfo sProfilingCategoryPairInfo[] = {
+  MOZ_PROFILING_CATEGORY_LIST(CATEGORY_INFO_BEGIN_CATEGORY,
+                              CATEGORY_INFO_SUBCATEGORY,
+                              CATEGORY_INFO_END_CATEGORY)
+};
+#undef CATEGORY_INFO_BEGIN_CATEGORY
+#undef CATEGORY_INFO_SUBCATEGORY
+#undef CATEGORY_INFO_END_CATEGORY
+
+// clang-format on
+
+JS_PUBLIC_API const ProfilingCategoryPairInfo& GetProfilingCategoryPairInfo(
+    ProfilingCategoryPair aCategoryPair) {
+  static_assert(
+      MOZ_ARRAY_LENGTH(sProfilingCategoryPairInfo) ==
+          uint32_t(ProfilingCategoryPair::COUNT),
+      "sProfilingCategoryPairInfo and ProfilingCategory need to have the "
+      "same order and the same length");
+
+  uint32_t categoryPairIndex = uint32_t(aCategoryPair);
+  MOZ_RELEASE_ASSERT(categoryPairIndex <=
+                     uint32_t(ProfilingCategoryPair::LAST));
+  return sProfilingCategoryPairInfo[categoryPairIndex];
+}
+
+}  // namespace JS