Imported QtWebKit TP3 (git b57bc6801f1876c3220d5a4bfea33d620d477443)

Change-Id: I3b1d8a2808782c9f34d50240000e20cb38d3680f
Reviewed-by: Konstantin Tokarev <annulen@yandex.ru>

1 files changed, 320 insertions, 0 deletions

diff --git a/Source/JavaScriptCore/dfg/DFGOSRExitCompilerCommon.cpp b/Source/JavaScriptCore/dfg/DFGOSRExitCompilerCommon.cpp
new file mode 100644
index 000000000..00bbe8b4e
--- /dev/null
+++ b/Source/JavaScriptCore/dfg/DFGOSRExitCompilerCommon.cpp
@@ -0,0 +1,320 @@
+/*
+ * Copyright (C) 2013-2015 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#include "config.h"
+#include "DFGOSRExitCompilerCommon.h"
+
+#if ENABLE(DFG_JIT)
+
+#include "DFGJITCode.h"
+#include "DFGOperations.h"
+#include "JIT.h"
+#include "JSCJSValueInlines.h"
+#include "JSCInlines.h"
+
+namespace JSC { namespace DFG {
+
+void handleExitCounts(CCallHelpers& jit, const OSRExitBase& exit)
+{
+    jit.add32(AssemblyHelpers::TrustedImm32(1), AssemblyHelpers::AbsoluteAddress(&exit.m_count));
+
+    if (!exitKindMayJettison(exit.m_kind))
+        return;
+    
+    jit.move(AssemblyHelpers::TrustedImmPtr(jit.codeBlock()), GPRInfo::regT0);
+    
+    AssemblyHelpers::Jump tooFewFails;
+    
+    jit.load32(AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfOSRExitCounter()), GPRInfo::regT2);
+    jit.add32(AssemblyHelpers::TrustedImm32(1), GPRInfo::regT2);
+    jit.store32(GPRInfo::regT2, AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfOSRExitCounter()));
+    
+    jit.move(AssemblyHelpers::TrustedImmPtr(jit.baselineCodeBlock()), GPRInfo::regT0);
+    AssemblyHelpers::Jump reoptimizeNow = jit.branch32(
+        AssemblyHelpers::GreaterThanOrEqual,
+        AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecuteCounter()),
+        AssemblyHelpers::TrustedImm32(0));
+    
+    // We want to figure out if there's a possibility that we're in a loop. For the outermost
+    // code block in the inline stack, we handle this appropriately by having the loop OSR trigger
+    // check the exit count of the replacement of the CodeBlock from which we are OSRing. The
+    // problem is the inlined functions, which might also have loops, but whose baseline versions
+    // don't know where to look for the exit count. Figure out if those loops are severe enough
+    // that we had tried to OSR enter. If so, then we should use the loop reoptimization trigger.
+    // Otherwise, we should use the normal reoptimization trigger.
+    
+    AssemblyHelpers::JumpList loopThreshold;
+    
+    for (InlineCallFrame* inlineCallFrame = exit.m_codeOrigin.inlineCallFrame; inlineCallFrame; inlineCallFrame = inlineCallFrame->directCaller.inlineCallFrame) {
+        loopThreshold.append(
+            jit.branchTest8(
+                AssemblyHelpers::NonZero,
+                AssemblyHelpers::AbsoluteAddress(
+                    inlineCallFrame->baselineCodeBlock->ownerScriptExecutable()->addressOfDidTryToEnterInLoop())));
+    }
+    
+    jit.move(
+        AssemblyHelpers::TrustedImm32(jit.codeBlock()->exitCountThresholdForReoptimization()),
+        GPRInfo::regT1);
+    
+    if (!loopThreshold.empty()) {
+        AssemblyHelpers::Jump done = jit.jump();
+
+        loopThreshold.link(&jit);
+        jit.move(
+            AssemblyHelpers::TrustedImm32(
+                jit.codeBlock()->exitCountThresholdForReoptimizationFromLoop()),
+            GPRInfo::regT1);
+        
+        done.link(&jit);
+    }
+    
+    tooFewFails = jit.branch32(AssemblyHelpers::BelowOrEqual, GPRInfo::regT2, GPRInfo::regT1);
+    
+    reoptimizeNow.link(&jit);
+    
+    // Reoptimize as soon as possible.
+#if !NUMBER_OF_ARGUMENT_REGISTERS
+    jit.poke(GPRInfo::regT0);
+    jit.poke(AssemblyHelpers::TrustedImmPtr(&exit), 1);
+#else
+    jit.move(GPRInfo::regT0, GPRInfo::argumentGPR0);
+    jit.move(AssemblyHelpers::TrustedImmPtr(&exit), GPRInfo::argumentGPR1);
+#endif
+    jit.move(AssemblyHelpers::TrustedImmPtr(bitwise_cast<void*>(triggerReoptimizationNow)), GPRInfo::nonArgGPR0);
+    jit.call(GPRInfo::nonArgGPR0);
+    AssemblyHelpers::Jump doneAdjusting = jit.jump();
+    
+    tooFewFails.link(&jit);
+    
+    // Adjust the execution counter such that the target is to only optimize after a while.
+    int32_t activeThreshold =
+        jit.baselineCodeBlock()->adjustedCounterValue(
+            Options::thresholdForOptimizeAfterLongWarmUp());
+    int32_t targetValue = applyMemoryUsageHeuristicsAndConvertToInt(
+        activeThreshold, jit.baselineCodeBlock());
+    int32_t clippedValue;
+    switch (jit.codeBlock()->jitType()) {
+    case JITCode::DFGJIT:
+        clippedValue = BaselineExecutionCounter::clippedThreshold(jit.codeBlock()->globalObject(), targetValue);
+        break;
+    case JITCode::FTLJIT:
+        clippedValue = UpperTierExecutionCounter::clippedThreshold(jit.codeBlock()->globalObject(), targetValue);
+        break;
+    default:
+        RELEASE_ASSERT_NOT_REACHED();
+#if COMPILER_QUIRK(CONSIDERS_UNREACHABLE_CODE)
+        clippedValue = 0; // Make some compilers, and mhahnenberg, happy.
+#endif
+        break;
+    }
+    jit.store32(AssemblyHelpers::TrustedImm32(-clippedValue), AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecuteCounter()));
+    jit.store32(AssemblyHelpers::TrustedImm32(activeThreshold), AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecutionActiveThreshold()));
+    jit.store32(AssemblyHelpers::TrustedImm32(formattedTotalExecutionCount(clippedValue)), AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecutionTotalCount()));
+    
+    doneAdjusting.link(&jit);
+}
+
+void reifyInlinedCallFrames(CCallHelpers& jit, const OSRExitBase& exit)
+{
+    // FIXME: We shouldn't leave holes on the stack when performing an OSR exit
+    // in presence of inlined tail calls.
+    // https://bugs.webkit.org/show_bug.cgi?id=147511
+    ASSERT(jit.baselineCodeBlock()->jitType() == JITCode::BaselineJIT);
+    jit.storePtr(AssemblyHelpers::TrustedImmPtr(jit.baselineCodeBlock()), AssemblyHelpers::addressFor((VirtualRegister)JSStack::CodeBlock));
+
+    const CodeOrigin* codeOrigin;
+    for (codeOrigin = &exit.m_codeOrigin; codeOrigin && codeOrigin->inlineCallFrame; codeOrigin = codeOrigin->inlineCallFrame->getCallerSkippingTailCalls()) {
+        InlineCallFrame* inlineCallFrame = codeOrigin->inlineCallFrame;
+        CodeBlock* baselineCodeBlock = jit.baselineCodeBlockFor(*codeOrigin);
+        InlineCallFrame::Kind trueCallerCallKind;
+        CodeOrigin* trueCaller = inlineCallFrame->getCallerSkippingTailCalls(&trueCallerCallKind);
+        GPRReg callerFrameGPR = GPRInfo::callFrameRegister;
+
+        if (!trueCaller) {
+            ASSERT(inlineCallFrame->isTail());
+            jit.loadPtr(AssemblyHelpers::Address(GPRInfo::callFrameRegister, CallFrame::returnPCOffset()), GPRInfo::regT3);
+            jit.storePtr(GPRInfo::regT3, AssemblyHelpers::addressForByteOffset(inlineCallFrame->returnPCOffset()));
+            jit.loadPtr(AssemblyHelpers::Address(GPRInfo::callFrameRegister, CallFrame::callerFrameOffset()), GPRInfo::regT3);
+            callerFrameGPR = GPRInfo::regT3;
+        } else {
+            CodeBlock* baselineCodeBlockForCaller = jit.baselineCodeBlockFor(*trueCaller);
+            unsigned callBytecodeIndex = trueCaller->bytecodeIndex;
+            void* jumpTarget = nullptr;
+
+            switch (trueCallerCallKind) {
+            case InlineCallFrame::Call:
+            case InlineCallFrame::Construct:
+            case InlineCallFrame::CallVarargs:
+            case InlineCallFrame::ConstructVarargs:
+            case InlineCallFrame::TailCall:
+            case InlineCallFrame::TailCallVarargs: {
+                CallLinkInfo* callLinkInfo =
+                    baselineCodeBlockForCaller->getCallLinkInfoForBytecodeIndex(callBytecodeIndex);
+                RELEASE_ASSERT(callLinkInfo);
+
+                jumpTarget = callLinkInfo->callReturnLocation().executableAddress();
+                break;
+            }
+
+            case InlineCallFrame::GetterCall:
+            case InlineCallFrame::SetterCall: {
+                StructureStubInfo* stubInfo =
+                    baselineCodeBlockForCaller->findStubInfo(CodeOrigin(callBytecodeIndex));
+                RELEASE_ASSERT(stubInfo);
+
+                jumpTarget = stubInfo->callReturnLocation.labelAtOffset(
+                    stubInfo->patch.deltaCallToDone).executableAddress();
+                break;
+            }
+
+            default:
+                RELEASE_ASSERT_NOT_REACHED();
+            }
+
+            if (trueCaller->inlineCallFrame) {
+                jit.addPtr(
+                    AssemblyHelpers::TrustedImm32(trueCaller->inlineCallFrame->stackOffset * sizeof(EncodedJSValue)),
+                    GPRInfo::callFrameRegister,
+                    GPRInfo::regT3);
+                callerFrameGPR = GPRInfo::regT3;
+            }
+
+            jit.storePtr(AssemblyHelpers::TrustedImmPtr(jumpTarget), AssemblyHelpers::addressForByteOffset(inlineCallFrame->returnPCOffset()));
+        }
+
+        jit.storePtr(AssemblyHelpers::TrustedImmPtr(baselineCodeBlock), AssemblyHelpers::addressFor((VirtualRegister)(inlineCallFrame->stackOffset + JSStack::CodeBlock)));
+
+        // Restore the inline call frame's callee save registers.
+        // If this inlined frame is a tail call that will return back to the original caller, we need to
+        // copy the prior contents of the tag registers already saved for the outer frame to this frame.
+        jit.emitSaveOrCopyCalleeSavesFor(
+            baselineCodeBlock,
+            static_cast<VirtualRegister>(inlineCallFrame->stackOffset),
+            trueCaller ? AssemblyHelpers::UseExistingTagRegisterContents : AssemblyHelpers::CopyBaselineCalleeSavedRegistersFromBaseFrame,
+            GPRInfo::regT2);
+
+        if (!inlineCallFrame->isVarargs())
+            jit.store32(AssemblyHelpers::TrustedImm32(inlineCallFrame->arguments.size()), AssemblyHelpers::payloadFor((VirtualRegister)(inlineCallFrame->stackOffset + JSStack::ArgumentCount)));
+#if USE(JSVALUE64)
+        jit.store64(callerFrameGPR, AssemblyHelpers::addressForByteOffset(inlineCallFrame->callerFrameOffset()));
+        uint32_t locationBits = CallSiteIndex(codeOrigin->bytecodeIndex).bits();
+        jit.store32(AssemblyHelpers::TrustedImm32(locationBits), AssemblyHelpers::tagFor((VirtualRegister)(inlineCallFrame->stackOffset + JSStack::ArgumentCount)));
+        if (!inlineCallFrame->isClosureCall)
+            jit.store64(AssemblyHelpers::TrustedImm64(JSValue::encode(JSValue(inlineCallFrame->calleeConstant()))), AssemblyHelpers::addressFor((VirtualRegister)(inlineCallFrame->stackOffset + JSStack::Callee)));
+#else // USE(JSVALUE64) // so this is the 32-bit part
+        jit.storePtr(callerFrameGPR, AssemblyHelpers::addressForByteOffset(inlineCallFrame->callerFrameOffset()));
+        Instruction* instruction = baselineCodeBlock->instructions().begin() + codeOrigin->bytecodeIndex;
+        uint32_t locationBits = CallSiteIndex(instruction).bits();
+        jit.store32(AssemblyHelpers::TrustedImm32(locationBits), AssemblyHelpers::tagFor((VirtualRegister)(inlineCallFrame->stackOffset + JSStack::ArgumentCount)));
+        jit.store32(AssemblyHelpers::TrustedImm32(JSValue::CellTag), AssemblyHelpers::tagFor((VirtualRegister)(inlineCallFrame->stackOffset + JSStack::Callee)));
+        if (!inlineCallFrame->isClosureCall)
+            jit.storePtr(AssemblyHelpers::TrustedImmPtr(inlineCallFrame->calleeConstant()), AssemblyHelpers::payloadFor((VirtualRegister)(inlineCallFrame->stackOffset + JSStack::Callee)));
+#endif // USE(JSVALUE64) // ending the #else part, so directly above is the 32-bit part
+    }
+
+    // Don't need to set the toplevel code origin if we only did inline tail calls
+    if (codeOrigin) {
+#if USE(JSVALUE64)
+        uint32_t locationBits = CallSiteIndex(codeOrigin->bytecodeIndex).bits();
+#else
+        Instruction* instruction = jit.baselineCodeBlock()->instructions().begin() + codeOrigin->bytecodeIndex;
+        uint32_t locationBits = CallSiteIndex(instruction).bits();
+#endif
+        jit.store32(AssemblyHelpers::TrustedImm32(locationBits), AssemblyHelpers::tagFor((VirtualRegister)(JSStack::ArgumentCount)));
+    }
+}
+
+static void osrWriteBarrier(CCallHelpers& jit, GPRReg owner, GPRReg scratch)
+{
+    AssemblyHelpers::Jump ownerIsRememberedOrInEden = jit.jumpIfIsRememberedOrInEden(owner);
+
+    // We need these extra slots because setupArgumentsWithExecState will use poke on x86.
+#if CPU(X86)
+    jit.subPtr(MacroAssembler::TrustedImm32(sizeof(void*) * 3), MacroAssembler::stackPointerRegister);
+#endif
+
+    jit.setupArgumentsWithExecState(owner);
+    jit.move(MacroAssembler::TrustedImmPtr(reinterpret_cast<void*>(operationOSRWriteBarrier)), scratch);
+    jit.call(scratch);
+
+#if CPU(X86)
+    jit.addPtr(MacroAssembler::TrustedImm32(sizeof(void*) * 3), MacroAssembler::stackPointerRegister);
+#endif
+
+    ownerIsRememberedOrInEden.link(&jit);
+}
+
+void adjustAndJumpToTarget(CCallHelpers& jit, const OSRExitBase& exit)
+{
+    jit.move(
+        AssemblyHelpers::TrustedImmPtr(
+            jit.codeBlock()->baselineAlternative()), GPRInfo::argumentGPR1);
+    osrWriteBarrier(jit, GPRInfo::argumentGPR1, GPRInfo::nonArgGPR0);
+
+    // We barrier all inlined frames -- and not just the current inline stack --
+    // because we don't know which inlined function owns the value profile that
+    // we'll update when we exit. In the case of "f() { a(); b(); }", if both
+    // a and b are inlined, we might exit inside b due to a bad value loaded
+    // from a.
+    // FIXME: MethodOfGettingAValueProfile should remember which CodeBlock owns
+    // the value profile.
+    InlineCallFrameSet* inlineCallFrames = jit.codeBlock()->jitCode()->dfgCommon()->inlineCallFrames.get();
+    if (inlineCallFrames) {
+        for (InlineCallFrame* inlineCallFrame : *inlineCallFrames) {
+            jit.move(
+                AssemblyHelpers::TrustedImmPtr(
+                    inlineCallFrame->baselineCodeBlock.get()), GPRInfo::argumentGPR1);
+            osrWriteBarrier(jit, GPRInfo::argumentGPR1, GPRInfo::nonArgGPR0);
+        }
+    }
+
+    if (exit.m_codeOrigin.inlineCallFrame)
+        jit.addPtr(AssemblyHelpers::TrustedImm32(exit.m_codeOrigin.inlineCallFrame->stackOffset * sizeof(EncodedJSValue)), GPRInfo::callFrameRegister);
+
+    CodeBlock* codeBlockForExit = jit.baselineCodeBlockFor(exit.m_codeOrigin);
+    Vector<BytecodeAndMachineOffset>& decodedCodeMap = jit.decodedCodeMapFor(codeBlockForExit);
+    
+    BytecodeAndMachineOffset* mapping = binarySearch<BytecodeAndMachineOffset, unsigned>(decodedCodeMap, decodedCodeMap.size(), exit.m_codeOrigin.bytecodeIndex, BytecodeAndMachineOffset::getBytecodeIndex);
+    
+    ASSERT(mapping);
+    ASSERT(mapping->m_bytecodeIndex == exit.m_codeOrigin.bytecodeIndex);
+    
+    void* jumpTarget = codeBlockForExit->jitCode()->executableAddressAtOffset(mapping->m_machineCodeOffset);
+
+    jit.addPtr(AssemblyHelpers::TrustedImm32(JIT::stackPointerOffsetFor(codeBlockForExit) * sizeof(Register)), GPRInfo::callFrameRegister, AssemblyHelpers::stackPointerRegister);
+    if (exit.isExceptionHandler()) {
+        // Since we're jumping to op_catch, we need to set callFrameForCatch.
+        jit.storePtr(GPRInfo::callFrameRegister, jit.vm()->addressOfCallFrameForCatch());
+    }
+    
+    jit.move(AssemblyHelpers::TrustedImmPtr(jumpTarget), GPRInfo::regT2);
+    jit.jump(GPRInfo::regT2);
+}
+
+} } // namespace JSC::DFG
+
+#endif // ENABLE(DFG_JIT)
+