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comparison: js/src/jit/BaselineFrame.cpp
js/src/jit/BaselineFrame.cpp
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- TOR_BUG_3246
- changeset 7
- 129ffea94266
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| -1:000000000000 | 0:7e5547417ab8 |
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| 1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- | |
| 2 * vim: set ts=8 sts=4 et sw=4 tw=99: | |
| 3 * This Source Code Form is subject to the terms of the Mozilla Public | |
| 4 * License, v. 2.0. If a copy of the MPL was not distributed with this | |
| 5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ | |
| 6 | |
| 7 #include "jit/BaselineFrame-inl.h" | |
| 8 | |
| 9 #include "jit/BaselineJIT.h" | |
| 10 #include "jit/Ion.h" | |
| 11 #include "vm/Debugger.h" | |
| 12 #include "vm/ScopeObject.h" | |
| 13 | |
| 14 #include "jit/IonFrames-inl.h" | |
| 15 #include "vm/Stack-inl.h" | |
| 16 | |
| 17 using namespace js; | |
| 18 using namespace js::jit; | |
| 19 | |
| 20 static void | |
| 21 MarkLocals(BaselineFrame *frame, JSTracer *trc, unsigned start, unsigned end) | |
| 22 { | |
| 23 if (start < end) { | |
| 24 // Stack grows down. | |
| 25 Value *last = frame->valueSlot(end - 1); | |
| 26 gc::MarkValueRootRange(trc, end - start, last, "baseline-stack"); | |
| 27 } | |
| 28 } | |
| 29 | |
| 30 void | |
| 31 BaselineFrame::trace(JSTracer *trc, JitFrameIterator &frameIterator) | |
| 32 { | |
| 33 replaceCalleeToken(MarkCalleeToken(trc, calleeToken())); | |
| 34 | |
| 35 gc::MarkValueRoot(trc, &thisValue(), "baseline-this"); | |
| 36 | |
| 37 // Mark actual and formal args. | |
| 38 if (isNonEvalFunctionFrame()) { | |
| 39 unsigned numArgs = js::Max(numActualArgs(), numFormalArgs()); | |
| 40 gc::MarkValueRootRange(trc, numArgs, argv(), "baseline-args"); | |
| 41 } | |
| 42 | |
| 43 // Mark scope chain, if it exists. | |
| 44 if (scopeChain_) | |
| 45 gc::MarkObjectRoot(trc, &scopeChain_, "baseline-scopechain"); | |
| 46 | |
| 47 // Mark return value. | |
| 48 if (hasReturnValue()) | |
| 49 gc::MarkValueRoot(trc, returnValue().address(), "baseline-rval"); | |
| 50 | |
| 51 if (isEvalFrame()) | |
| 52 gc::MarkScriptRoot(trc, &evalScript_, "baseline-evalscript"); | |
| 53 | |
| 54 if (hasArgsObj()) | |
| 55 gc::MarkObjectRoot(trc, &argsObj_, "baseline-args-obj"); | |
| 56 | |
| 57 // Mark locals and stack values. | |
| 58 JSScript *script = this->script(); | |
| 59 size_t nfixed = script->nfixed(); | |
| 60 size_t nlivefixed = script->nfixedvars(); | |
| 61 | |
| 62 if (nfixed != nlivefixed) { | |
| 63 jsbytecode *pc; | |
| 64 NestedScopeObject *staticScope; | |
| 65 | |
| 66 frameIterator.baselineScriptAndPc(nullptr, &pc); | |
| 67 staticScope = script->getStaticScope(pc); | |
| 68 while (staticScope && !staticScope->is<StaticBlockObject>()) | |
| 69 staticScope = staticScope->enclosingNestedScope(); | |
| 70 | |
| 71 if (staticScope) { | |
| 72 StaticBlockObject &blockObj = staticScope->as<StaticBlockObject>(); | |
| 73 nlivefixed = blockObj.localOffset() + blockObj.numVariables(); | |
| 74 } | |
| 75 } | |
| 76 | |
| 77 JS_ASSERT(nlivefixed <= nfixed); | |
| 78 JS_ASSERT(nlivefixed >= script->nfixedvars()); | |
| 79 | |
| 80 // NB: It is possible that numValueSlots() could be zero, even if nfixed is | |
| 81 // nonzero. This is the case if the function has an early stack check. | |
| 82 if (numValueSlots() == 0) | |
| 83 return; | |
| 84 | |
| 85 JS_ASSERT(nfixed <= numValueSlots()); | |
| 86 | |
| 87 if (nfixed == nlivefixed) { | |
| 88 // All locals are live. | |
| 89 MarkLocals(this, trc, 0, numValueSlots()); | |
| 90 } else { | |
| 91 // Mark operand stack. | |
| 92 MarkLocals(this, trc, nfixed, numValueSlots()); | |
| 93 | |
| 94 // Clear dead locals. | |
| 95 while (nfixed > nlivefixed) | |
| 96 unaliasedLocal(--nfixed, DONT_CHECK_ALIASING).setUndefined(); | |
| 97 | |
| 98 // Mark live locals. | |
| 99 MarkLocals(this, trc, 0, nlivefixed); | |
| 100 } | |
| 101 } | |
| 102 | |
| 103 bool | |
| 104 BaselineFrame::copyRawFrameSlots(AutoValueVector *vec) const | |
| 105 { | |
| 106 unsigned nfixed = script()->nfixed(); | |
| 107 unsigned nformals = numFormalArgs(); | |
| 108 | |
| 109 if (!vec->resize(nformals + nfixed)) | |
| 110 return false; | |
| 111 | |
| 112 mozilla::PodCopy(vec->begin(), argv(), nformals); | |
| 113 for (unsigned i = 0; i < nfixed; i++) | |
| 114 (*vec)[nformals + i] = *valueSlot(i); | |
| 115 return true; | |
| 116 } | |
| 117 | |
| 118 bool | |
| 119 BaselineFrame::strictEvalPrologue(JSContext *cx) | |
| 120 { | |
| 121 JS_ASSERT(isStrictEvalFrame()); | |
| 122 | |
| 123 CallObject *callobj = CallObject::createForStrictEval(cx, this); | |
| 124 if (!callobj) | |
| 125 return false; | |
| 126 | |
| 127 pushOnScopeChain(*callobj); | |
| 128 flags_ |= HAS_CALL_OBJ; | |
| 129 return true; | |
| 130 } | |
| 131 | |
| 132 bool | |
| 133 BaselineFrame::heavyweightFunPrologue(JSContext *cx) | |
| 134 { | |
| 135 return initFunctionScopeObjects(cx); | |
| 136 } | |
| 137 | |
| 138 bool | |
| 139 BaselineFrame::initFunctionScopeObjects(JSContext *cx) | |
| 140 { | |
| 141 JS_ASSERT(isNonEvalFunctionFrame()); | |
| 142 JS_ASSERT(fun()->isHeavyweight()); | |
| 143 | |
| 144 CallObject *callobj = CallObject::createForFunction(cx, this); | |
| 145 if (!callobj) | |
| 146 return false; | |
| 147 | |
| 148 pushOnScopeChain(*callobj); | |
| 149 flags_ |= HAS_CALL_OBJ; | |
| 150 return true; | |
| 151 } | |
| 152 | |
| 153 bool | |
| 154 BaselineFrame::initForOsr(InterpreterFrame *fp, uint32_t numStackValues) | |
| 155 { | |
| 156 mozilla::PodZero(this); | |
| 157 | |
| 158 scopeChain_ = fp->scopeChain(); | |
| 159 | |
| 160 if (fp->hasCallObjUnchecked()) | |
| 161 flags_ |= BaselineFrame::HAS_CALL_OBJ; | |
| 162 | |
| 163 if (fp->isEvalFrame()) { | |
| 164 flags_ |= BaselineFrame::EVAL; | |
| 165 evalScript_ = fp->script(); | |
| 166 } | |
| 167 | |
| 168 if (fp->script()->needsArgsObj() && fp->hasArgsObj()) { | |
| 169 flags_ |= BaselineFrame::HAS_ARGS_OBJ; | |
| 170 argsObj_ = &fp->argsObj(); | |
| 171 } | |
| 172 | |
| 173 if (fp->hasHookData()) { | |
| 174 flags_ |= BaselineFrame::HAS_HOOK_DATA; | |
| 175 hookData_ = fp->hookData(); | |
| 176 } | |
| 177 | |
| 178 if (fp->hasReturnValue()) | |
| 179 setReturnValue(fp->returnValue()); | |
| 180 | |
| 181 // If the interpreter pushed an SPS frame when it entered the function, the | |
| 182 // interpreter will pop it after the OSR trampoline returns. In order for | |
| 183 // the Baseline frame to have its SPS flag set, it must have its own SPS | |
| 184 // frame, which the Baseline code will pop on return. Note that the | |
| 185 // profiler may have been enabled or disabled after the function was entered | |
| 186 // but before OSR. | |
| 187 JSContext *cx = GetJSContextFromJitCode(); | |
| 188 SPSProfiler *p = &(cx->runtime()->spsProfiler); | |
| 189 if (p->enabled()) { | |
| 190 p->enter(fp->script(), fp->maybeFun()); | |
| 191 flags_ |= BaselineFrame::HAS_PUSHED_SPS_FRAME; | |
| 192 } | |
| 193 | |
| 194 frameSize_ = BaselineFrame::FramePointerOffset + | |
| 195 BaselineFrame::Size() + | |
| 196 numStackValues * sizeof(Value); | |
| 197 | |
| 198 JS_ASSERT(numValueSlots() == numStackValues); | |
| 199 | |
| 200 for (uint32_t i = 0; i < numStackValues; i++) | |
| 201 *valueSlot(i) = fp->slots()[i]; | |
| 202 | |
| 203 if (cx->compartment()->debugMode()) { | |
| 204 // In debug mode, update any Debugger.Frame objects for the | |
| 205 // InterpreterFrame to point to the BaselineFrame. | |
| 206 | |
| 207 // The caller pushed a fake return address. ScriptFrameIter, used by the | |
| 208 // debugger, wants a valid return address, but it's okay to just pick one. | |
| 209 // In debug mode there's always at least 1 ICEntry (since there are always | |
| 210 // debug prologue/epilogue calls). | |
| 211 JitFrameIterator iter(cx); | |
| 212 JS_ASSERT(iter.returnAddress() == nullptr); | |
| 213 BaselineScript *baseline = fp->script()->baselineScript(); | |
| 214 iter.current()->setReturnAddress(baseline->returnAddressForIC(baseline->icEntry(0))); | |
| 215 | |
| 216 if (!Debugger::handleBaselineOsr(cx, fp, this)) | |
| 217 return false; | |
| 218 } | |
| 219 | |
| 220 return true; | |
| 221 } |
