The Tor Browser: js/src/jit/BaselineFrame.cpp@6474c204b198 (annotated)

js/src/jit/BaselineFrame.cpp@6474c204b198 (annotated)

js/src/jit/BaselineFrame.cpp

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* -*- 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/ScopeObject.h"
 #include "jit/IonFrames-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);
         gc::MarkValueRootRange(trc, end - start, last, "baseline-stack");
     }
 }
 void
 BaselineFrame::trace(JSTracer *trc, JitFrameIterator &frameIterator)
 {
     replaceCalleeToken(MarkCalleeToken(trc, calleeToken()));
     gc::MarkValueRoot(trc, &thisValue(), "baseline-this");
     // Mark actual and formal args.
     if (isNonEvalFunctionFrame()) {
         unsigned numArgs = js::Max(numActualArgs(), numFormalArgs());
         gc::MarkValueRootRange(trc, numArgs, argv(), "baseline-args");
     }
     // Mark scope chain, if it exists.
     if (scopeChain_)
         gc::MarkObjectRoot(trc, &scopeChain_, "baseline-scopechain");
     // Mark return value.
     if (hasReturnValue())
         gc::MarkValueRoot(trc, returnValue().address(), "baseline-rval");
     if (isEvalFrame())
         gc::MarkScriptRoot(trc, &evalScript_, "baseline-evalscript");
     if (hasArgsObj())
         gc::MarkObjectRoot(trc, &argsObj_, "baseline-args-obj");
     // Mark locals and stack values.
     JSScript *script = this->script();
     size_t nfixed = script->nfixed();
     size_t nlivefixed = script->nfixedvars();
     if (nfixed != nlivefixed) {
         jsbytecode *pc;
         NestedScopeObject *staticScope;
         frameIterator.baselineScriptAndPc(nullptr, &pc);
         staticScope = script->getStaticScope(pc);
         while (staticScope && !staticScope->is<StaticBlockObject>())
             staticScope = staticScope->enclosingNestedScope();
         if (staticScope) {
             StaticBlockObject &blockObj = staticScope->as<StaticBlockObject>();
             nlivefixed = blockObj.localOffset() + blockObj.numVariables();
         }
     }
     JS_ASSERT(nlivefixed <= nfixed);
     JS_ASSERT(nlivefixed >= script->nfixedvars());
     // 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;
     JS_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 locals.
         while (nfixed > nlivefixed)
             unaliasedLocal(--nfixed, DONT_CHECK_ALIASING).setUndefined();
         // Mark live locals.
         MarkLocals(this, trc, 0, nlivefixed);
     }
 }
 bool
 BaselineFrame::copyRawFrameSlots(AutoValueVector *vec) const
 {
     unsigned nfixed = script()->nfixed();
     unsigned nformals = numFormalArgs();
     if (!vec->resize(nformals + nfixed))
         return false;
     mozilla::PodCopy(vec->begin(), argv(), nformals);
     for (unsigned i = 0; i < nfixed; i++)
         (*vec)[nformals + i] = *valueSlot(i);
     return true;
 }
 bool
 BaselineFrame::strictEvalPrologue(JSContext *cx)
 {
     JS_ASSERT(isStrictEvalFrame());
     CallObject *callobj = CallObject::createForStrictEval(cx, this);
     if (!callobj)
         return false;
     pushOnScopeChain(*callobj);
     flags_ |= HAS_CALL_OBJ;
     return true;
 }
 bool
 BaselineFrame::heavyweightFunPrologue(JSContext *cx)
 {
     return initFunctionScopeObjects(cx);
 }
 bool
 BaselineFrame::initFunctionScopeObjects(JSContext *cx)
 {
     JS_ASSERT(isNonEvalFunctionFrame());
     JS_ASSERT(fun()->isHeavyweight());
     CallObject *callobj = CallObject::createForFunction(cx, this);
     if (!callobj)
         return false;
     pushOnScopeChain(*callobj);
     flags_ |= HAS_CALL_OBJ;
     return true;
 }
 bool
 BaselineFrame::initForOsr(InterpreterFrame *fp, uint32_t numStackValues)
 {
     mozilla::PodZero(this);
     scopeChain_ = fp->scopeChain();
     if (fp->hasCallObjUnchecked())
         flags_ |= BaselineFrame::HAS_CALL_OBJ;
     if (fp->isEvalFrame()) {
         flags_ |= BaselineFrame::EVAL;
         evalScript_ = fp->script();
     }
     if (fp->script()->needsArgsObj() && fp->hasArgsObj()) {
         flags_ |= BaselineFrame::HAS_ARGS_OBJ;
         argsObj_ = &fp->argsObj();
     }
     if (fp->hasHookData()) {
         flags_ |= BaselineFrame::HAS_HOOK_DATA;
         hookData_ = fp->hookData();
     }
     if (fp->hasReturnValue())
         setReturnValue(fp->returnValue());
     // If the interpreter pushed an SPS frame when it entered the function, the
     // interpreter will pop it after the OSR trampoline returns.  In order for
     // the Baseline frame to have its SPS flag set, it must have its own SPS
     // frame, which the Baseline code will pop on return.  Note that the
     // profiler may have been enabled or disabled after the function was entered
     // but before OSR.
     JSContext *cx = GetJSContextFromJitCode();
     SPSProfiler *p = &(cx->runtime()->spsProfiler);
     if (p->enabled()) {
         p->enter(fp->script(), fp->maybeFun());
         flags_ |= BaselineFrame::HAS_PUSHED_SPS_FRAME;
     }
     frameSize_ = BaselineFrame::FramePointerOffset +
         BaselineFrame::Size() +
         numStackValues * sizeof(Value);
     JS_ASSERT(numValueSlots() == numStackValues);
     for (uint32_t i = 0; i < numStackValues; i++)
         *valueSlot(i) = fp->slots()[i];
     if (cx->compartment()->debugMode()) {
         // In debug mode, 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);
         JS_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;
     }
     return true;
 }

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js/src/jit/BaselineFrame.cpp@6474c204b198 (annotated)

js/src/jit/BaselineFrame.cpp