1 files changed, 157 insertions, 0 deletions
diff --git a/js/src/jit/BaselineFrame.cpp b/js/src/jit/BaselineFrame.cpp
new file mode 100644
index 000000000..6c9864ece
--- /dev/null
+++ b/js/src/jit/BaselineFrame.cpp
@@ -0,0 +1,157 @@
+/* -*- 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/. */
+
+#include "jit/BaselineFrame-inl.h"
+
+#include "jit/BaselineJIT.h"
+#include "jit/Ion.h"
+#include "vm/Debugger.h"
+#include "vm/EnvironmentObject.h"
+
+#include "jit/JitFrames-inl.h"
+#include "vm/Stack-inl.h"
+
+using namespace js;
+using namespace js::jit;
+
+static void
+MarkLocals(BaselineFrame* frame, JSTracer* trc, unsigned start, unsigned end)
+{
+    if (start < end) {
+        // Stack grows down.
+        Value* last = frame->valueSlot(end - 1);
+        TraceRootRange(trc, end - start, last, "baseline-stack");
+    }
+}
+
+void
+BaselineFrame::trace(JSTracer* trc, JitFrameIterator& frameIterator)
+{
+    replaceCalleeToken(MarkCalleeToken(trc, calleeToken()));
+
+    // Mark |this|, actual and formal args.
+    if (isFunctionFrame()) {
+        TraceRoot(trc, &thisArgument(), "baseline-this");
+
+        unsigned numArgs = js::Max(numActualArgs(), numFormalArgs());
+        TraceRootRange(trc, numArgs + isConstructing(), argv(), "baseline-args");
+    }
+
+    // Mark environment chain, if it exists.
+    if (envChain_)
+        TraceRoot(trc, &envChain_, "baseline-envchain");
+
+    // Mark return value.
+    if (hasReturnValue())
+        TraceRoot(trc, returnValue().address(), "baseline-rval");
+
+    if (isEvalFrame() && script()->isDirectEvalInFunction())
+        TraceRoot(trc, evalNewTargetAddress(), "baseline-evalNewTarget");
+
+    if (hasArgsObj())
+        TraceRoot(trc, &argsObj_, "baseline-args-obj");
+
+    // Mark locals and stack values.
+    JSScript* script = this->script();
+    size_t nfixed = script->nfixed();
+    jsbytecode* pc;
+    frameIterator.baselineScriptAndPc(nullptr, &pc);
+    size_t nlivefixed = script->calculateLiveFixed(pc);
+
+    // NB: It is possible that numValueSlots() could be zero, even if nfixed is
+    // nonzero.  This is the case if the function has an early stack check.
+    if (numValueSlots() == 0)
+        return;
+
+    MOZ_ASSERT(nfixed <= numValueSlots());
+
+    if (nfixed == nlivefixed) {
+        // All locals are live.
+        MarkLocals(this, trc, 0, numValueSlots());
+    } else {
+        // Mark operand stack.
+        MarkLocals(this, trc, nfixed, numValueSlots());
+
+        // Clear dead block-scoped locals.
+        while (nfixed > nlivefixed)
+            unaliasedLocal(--nfixed).setUndefined();
+
+        // Mark live locals.
+        MarkLocals(this, trc, 0, nlivefixed);
+    }
+
+    if (script->compartment()->debugEnvs)
+        script->compartment()->debugEnvs->markLiveFrame(trc, this);
+}
+
+bool
+BaselineFrame::isNonGlobalEvalFrame() const
+{
+    return isEvalFrame() && script()->enclosingScope()->as<EvalScope>().isNonGlobal();
+}
+
+bool
+BaselineFrame::initFunctionEnvironmentObjects(JSContext* cx)
+{
+    return js::InitFunctionEnvironmentObjects(cx, this);
+}
+
+bool
+BaselineFrame::pushVarEnvironment(JSContext* cx, HandleScope scope)
+{
+    return js::PushVarEnvironmentObject(cx, scope, this);
+}
+
+bool
+BaselineFrame::initForOsr(InterpreterFrame* fp, uint32_t numStackValues)
+{
+    mozilla::PodZero(this);
+
+    envChain_ = fp->environmentChain();
+
+    if (fp->hasInitialEnvironmentUnchecked())
+        flags_ |= BaselineFrame::HAS_INITIAL_ENV;
+
+    if (fp->script()->needsArgsObj() && fp->hasArgsObj()) {
+        flags_ |= BaselineFrame::HAS_ARGS_OBJ;
+        argsObj_ = &fp->argsObj();
+    }
+
+    if (fp->hasReturnValue())
+        setReturnValue(fp->returnValue());
+
+    frameSize_ = BaselineFrame::FramePointerOffset +
+        BaselineFrame::Size() +
+        numStackValues * sizeof(Value);
+
+    MOZ_ASSERT(numValueSlots() == numStackValues);
+
+    for (uint32_t i = 0; i < numStackValues; i++)
+        *valueSlot(i) = fp->slots()[i];
+
+    if (fp->isDebuggee()) {
+        JSContext* cx = GetJSContextFromMainThread();
+
+        // For debuggee frames, update any Debugger.Frame objects for the
+        // InterpreterFrame to point to the BaselineFrame.
+
+        // The caller pushed a fake return address. ScriptFrameIter, used by the
+        // debugger, wants a valid return address, but it's okay to just pick one.
+        // In debug mode there's always at least 1 ICEntry (since there are always
+        // debug prologue/epilogue calls).
+        JitFrameIterator iter(cx);
+        MOZ_ASSERT(iter.returnAddress() == nullptr);
+        BaselineScript* baseline = fp->script()->baselineScript();
+        iter.current()->setReturnAddress(baseline->returnAddressForIC(baseline->icEntry(0)));
+
+        if (!Debugger::handleBaselineOsr(cx, fp, this))
+            return false;
+
+        setIsDebuggee();
+    }
+
+    return true;
+}