Imported QtWebKit TP3 (git b57bc6801f1876c3220d5a4bfea33d620d477443)

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

1 files changed, 233 insertions, 0 deletions

diff --git a/Source/JavaScriptCore/ftl/FTLThunks.cpp b/Source/JavaScriptCore/ftl/FTLThunks.cpp
new file mode 100644
index 000000000..cfbc75b7c
--- /dev/null
+++ b/Source/JavaScriptCore/ftl/FTLThunks.cpp
@@ -0,0 +1,233 @@
+/*
+ * Copyright (C) 2013 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 "FTLThunks.h"
+
+#if ENABLE(FTL_JIT)
+
+#include "AssemblyHelpers.h"
+#include "DFGOSRExitCompilerCommon.h"
+#include "FPRInfo.h"
+#include "FTLOSRExitCompiler.h"
+#include "FTLOperations.h"
+#include "FTLSaveRestore.h"
+#include "GPRInfo.h"
+#include "LinkBuffer.h"
+
+namespace JSC { namespace FTL {
+
+using namespace DFG;
+
+enum class FrameAndStackAdjustmentRequirement {
+    Needed, 
+    NotNeeded 
+};
+
+static MacroAssemblerCodeRef genericGenerationThunkGenerator(
+    VM* vm, FunctionPtr generationFunction, const char* name, unsigned extraPopsToRestore, FrameAndStackAdjustmentRequirement frameAndStackAdjustmentRequirement)
+{
+    AssemblyHelpers jit(vm, 0);
+
+    if (frameAndStackAdjustmentRequirement == FrameAndStackAdjustmentRequirement::Needed) {
+        // This needs to happen before we use the scratch buffer because this function also uses the scratch buffer.
+        adjustFrameAndStackInOSRExitCompilerThunk<FTL::JITCode>(jit, vm, JITCode::FTLJIT);
+    }
+    
+    // Note that the "return address" will be the ID that we pass to the generation function.
+    
+    ptrdiff_t stackMisalignment = MacroAssembler::pushToSaveByteOffset();
+    
+    // Pretend that we're a C call frame.
+    jit.pushToSave(MacroAssembler::framePointerRegister);
+    jit.move(MacroAssembler::stackPointerRegister, MacroAssembler::framePointerRegister);
+    stackMisalignment += MacroAssembler::pushToSaveByteOffset();
+    
+    // Now create ourselves enough stack space to give saveAllRegisters() a scratch slot.
+    unsigned numberOfRequiredPops = 0;
+    do {
+        jit.pushToSave(GPRInfo::regT0);
+        stackMisalignment += MacroAssembler::pushToSaveByteOffset();
+        numberOfRequiredPops++;
+    } while (stackMisalignment % stackAlignmentBytes());
+    
+    ScratchBuffer* scratchBuffer = vm->scratchBufferForSize(requiredScratchMemorySizeInBytes());
+    char* buffer = static_cast<char*>(scratchBuffer->dataBuffer());
+    
+    saveAllRegisters(jit, buffer);
+    
+    // Tell GC mark phase how much of the scratch buffer is active during call.
+    jit.move(MacroAssembler::TrustedImmPtr(scratchBuffer->activeLengthPtr()), GPRInfo::nonArgGPR0);
+    jit.storePtr(MacroAssembler::TrustedImmPtr(requiredScratchMemorySizeInBytes()), GPRInfo::nonArgGPR0);
+
+    jit.loadPtr(GPRInfo::callFrameRegister, GPRInfo::argumentGPR0);
+    jit.peek(
+        GPRInfo::argumentGPR1,
+        (stackMisalignment - MacroAssembler::pushToSaveByteOffset()) / sizeof(void*));
+    MacroAssembler::Call functionCall = jit.call();
+    
+    // At this point we want to make a tail call to what was returned to us in the
+    // returnValueGPR. But at the same time as we do this, we must restore all registers.
+    // The way we will accomplish this is by arranging to have the tail call target in the
+    // return address "slot" (be it a register or the stack).
+    
+    jit.move(GPRInfo::returnValueGPR, GPRInfo::regT0);
+    
+    // Make sure we tell the GC that we're not using the scratch buffer anymore.
+    jit.move(MacroAssembler::TrustedImmPtr(scratchBuffer->activeLengthPtr()), GPRInfo::regT1);
+    jit.storePtr(MacroAssembler::TrustedImmPtr(0), GPRInfo::regT1);
+    
+    // Prepare for tail call.
+    while (numberOfRequiredPops--)
+        jit.popToRestore(GPRInfo::regT1);
+    jit.popToRestore(MacroAssembler::framePointerRegister);
+
+    // When we came in here, there was an additional thing pushed to the stack. Some clients want it
+    // popped before proceeding.
+    while (extraPopsToRestore--)
+        jit.popToRestore(GPRInfo::regT1);
+
+    // Put the return address wherever the return instruction wants it. On all platforms, this
+    // ensures that the return address is out of the way of register restoration.
+    jit.restoreReturnAddressBeforeReturn(GPRInfo::regT0);
+
+    restoreAllRegisters(jit, buffer);
+
+    jit.ret();
+    
+    LinkBuffer patchBuffer(*vm, jit, GLOBAL_THUNK_ID);
+    patchBuffer.link(functionCall, generationFunction);
+    return FINALIZE_CODE(patchBuffer, ("%s", name));
+}
+
+MacroAssemblerCodeRef osrExitGenerationThunkGenerator(VM* vm)
+{
+    unsigned extraPopsToRestore = 0;
+    return genericGenerationThunkGenerator(
+        vm, compileFTLOSRExit, "FTL OSR exit generation thunk", extraPopsToRestore, FrameAndStackAdjustmentRequirement::Needed);
+}
+
+MacroAssemblerCodeRef lazySlowPathGenerationThunkGenerator(VM* vm)
+{
+    unsigned extraPopsToRestore = 1;
+    return genericGenerationThunkGenerator(
+        vm, compileFTLLazySlowPath, "FTL lazy slow path generation thunk", extraPopsToRestore, FrameAndStackAdjustmentRequirement::NotNeeded);
+}
+
+static void registerClobberCheck(AssemblyHelpers& jit, RegisterSet dontClobber)
+{
+    if (!Options::clobberAllRegsInFTLICSlowPath())
+        return;
+    
+    RegisterSet clobber = RegisterSet::allRegisters();
+    clobber.exclude(RegisterSet::reservedHardwareRegisters());
+    clobber.exclude(RegisterSet::stackRegisters());
+    clobber.exclude(RegisterSet::calleeSaveRegisters());
+    clobber.exclude(dontClobber);
+    
+    GPRReg someGPR;
+    for (Reg reg = Reg::first(); reg <= Reg::last(); reg = reg.next()) {
+        if (!clobber.get(reg) || !reg.isGPR())
+            continue;
+        
+        jit.move(AssemblyHelpers::TrustedImm32(0x1337beef), reg.gpr());
+        someGPR = reg.gpr();
+    }
+    
+    for (Reg reg = Reg::first(); reg <= Reg::last(); reg = reg.next()) {
+        if (!clobber.get(reg) || !reg.isFPR())
+            continue;
+        
+        jit.move64ToDouble(someGPR, reg.fpr());
+    }
+}
+
+MacroAssemblerCodeRef slowPathCallThunkGenerator(VM& vm, const SlowPathCallKey& key)
+{
+    AssemblyHelpers jit(&vm, 0);
+    
+    // We want to save the given registers at the given offset, then we want to save the
+    // old return address somewhere past that offset, and then finally we want to make the
+    // call.
+    
+    size_t currentOffset = key.offset() + sizeof(void*);
+    
+#if CPU(X86) || CPU(X86_64)
+    currentOffset += sizeof(void*);
+#endif
+    
+    for (MacroAssembler::RegisterID reg = MacroAssembler::firstRegister(); reg <= MacroAssembler::lastRegister(); reg = static_cast<MacroAssembler::RegisterID>(reg + 1)) {
+        if (!key.usedRegisters().get(reg))
+            continue;
+        jit.storePtr(reg, AssemblyHelpers::Address(MacroAssembler::stackPointerRegister, currentOffset));
+        currentOffset += sizeof(void*);
+    }
+    
+    for (MacroAssembler::FPRegisterID reg = MacroAssembler::firstFPRegister(); reg <= MacroAssembler::lastFPRegister(); reg = static_cast<MacroAssembler::FPRegisterID>(reg + 1)) {
+        if (!key.usedRegisters().get(reg))
+            continue;
+        jit.storeDouble(reg, AssemblyHelpers::Address(MacroAssembler::stackPointerRegister, currentOffset));
+        currentOffset += sizeof(double);
+    }
+    
+    jit.preserveReturnAddressAfterCall(GPRInfo::nonArgGPR0);
+    jit.storePtr(GPRInfo::nonArgGPR0, AssemblyHelpers::Address(MacroAssembler::stackPointerRegister, key.offset()));
+    
+    registerClobberCheck(jit, key.argumentRegisters());
+    
+    AssemblyHelpers::Call call = jit.call();
+
+    jit.loadPtr(AssemblyHelpers::Address(MacroAssembler::stackPointerRegister, key.offset()), GPRInfo::nonPreservedNonReturnGPR);
+    jit.restoreReturnAddressBeforeReturn(GPRInfo::nonPreservedNonReturnGPR);
+    
+    for (MacroAssembler::FPRegisterID reg = MacroAssembler::lastFPRegister(); ; reg = static_cast<MacroAssembler::FPRegisterID>(reg - 1)) {
+        if (key.usedRegisters().get(reg)) {
+            currentOffset -= sizeof(double);
+            jit.loadDouble(AssemblyHelpers::Address(MacroAssembler::stackPointerRegister, currentOffset), reg);
+        }
+        if (reg == MacroAssembler::firstFPRegister())
+            break;
+    }
+    
+    for (MacroAssembler::RegisterID reg = MacroAssembler::lastRegister(); ; reg = static_cast<MacroAssembler::RegisterID>(reg - 1)) {
+        if (key.usedRegisters().get(reg)) {
+            currentOffset -= sizeof(void*);
+            jit.loadPtr(AssemblyHelpers::Address(MacroAssembler::stackPointerRegister, currentOffset), reg);
+        }
+        if (reg == MacroAssembler::firstRegister())
+            break;
+    }
+    
+    jit.ret();
+
+    LinkBuffer patchBuffer(vm, jit, GLOBAL_THUNK_ID);
+    patchBuffer.link(call, FunctionPtr(key.callTarget()));
+    return FINALIZE_CODE(patchBuffer, ("FTL slow path call thunk for %s", toCString(key).data()));
+}
+
+} } // namespace JSC::FTL
+
+#endif // ENABLE(FTL_JIT)
+