JavaScriptCore-7600.1.4.9.tar.gz

[apple/javascriptcore.git] / jit / ArityCheckFailReturnThunks.cpp

diff --git a/jit/ArityCheckFailReturnThunks.cpp b/jit/ArityCheckFailReturnThunks.cpp
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+/*
+ * 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 "ArityCheckFailReturnThunks.h"
+
+#if ENABLE(JIT)
+
+#include "AssemblyHelpers.h"
+#include "LinkBuffer.h"
+#include "JSCInlines.h"
+#include "StackAlignment.h"
+
+namespace JSC {
+
+ArityCheckFailReturnThunks::ArityCheckFailReturnThunks()
+    : m_nextSize(0)
+{
+}
+
+ArityCheckFailReturnThunks::~ArityCheckFailReturnThunks() { }
+
+CodeLocationLabel* ArityCheckFailReturnThunks::returnPCsFor(
+    VM& vm, unsigned numExpectedArgumentsIncludingThis)
+{
+    ASSERT(numExpectedArgumentsIncludingThis >= 1);
+    
+    numExpectedArgumentsIncludingThis = WTF::roundUpToMultipleOf(
+        stackAlignmentRegisters(), numExpectedArgumentsIncludingThis);
+    
+    {
+        ConcurrentJITLocker locker(m_lock);
+        if (numExpectedArgumentsIncludingThis < m_nextSize)
+            return m_returnPCArrays.last().get();
+    }
+    
+    ASSERT(!isCompilationThread());
+    
+    numExpectedArgumentsIncludingThis = std::max(numExpectedArgumentsIncludingThis, m_nextSize * 2);
+    
+    AssemblyHelpers jit(&vm, 0);
+    
+    Vector<AssemblyHelpers::Label> labels;
+    
+    for (unsigned size = m_nextSize; size <= numExpectedArgumentsIncludingThis; size += stackAlignmentRegisters()) {
+        labels.append(jit.label());
+        
+        jit.load32(
+            AssemblyHelpers::Address(
+                AssemblyHelpers::stackPointerRegister,
+                (JSStack::ArgumentCount - JSStack::CallerFrameAndPCSize) * sizeof(Register) +
+                PayloadOffset),
+            GPRInfo::regT4);
+        jit.add32(
+            AssemblyHelpers::TrustedImm32(
+                JSStack::CallFrameHeaderSize - JSStack::CallerFrameAndPCSize + size - 1),
+            GPRInfo::regT4, GPRInfo::regT2);
+        jit.lshift32(AssemblyHelpers::TrustedImm32(3), GPRInfo::regT2);
+        jit.addPtr(AssemblyHelpers::stackPointerRegister, GPRInfo::regT2);
+        jit.loadPtr(GPRInfo::regT2, GPRInfo::regT2);
+        
+        jit.addPtr(
+            AssemblyHelpers::TrustedImm32(size * sizeof(Register)),
+            AssemblyHelpers::stackPointerRegister);
+        
+        // Thunks like ours want to use the return PC to figure out where things
+        // were saved. So, we pay it forward.
+        jit.store32(
+            GPRInfo::regT4,
+            AssemblyHelpers::Address(
+                AssemblyHelpers::stackPointerRegister,
+                (JSStack::ArgumentCount - JSStack::CallerFrameAndPCSize) * sizeof(Register) +
+                PayloadOffset));
+        
+        jit.jump(GPRInfo::regT2);
+    }
+    
+    LinkBuffer linkBuffer(vm, jit, GLOBAL_THUNK_ID);
+    
+    unsigned returnPCsSize = numExpectedArgumentsIncludingThis / stackAlignmentRegisters() + 1;
+    std::unique_ptr<CodeLocationLabel[]> returnPCs =
+        std::make_unique<CodeLocationLabel[]>(returnPCsSize);
+    for (unsigned size = 0; size <= numExpectedArgumentsIncludingThis; size += stackAlignmentRegisters()) {
+        unsigned index = size / stackAlignmentRegisters();
+        RELEASE_ASSERT(index < returnPCsSize);
+        if (size < m_nextSize)
+            returnPCs[index] = m_returnPCArrays.last()[index];
+        else
+            returnPCs[index] = linkBuffer.locationOf(labels[(size - m_nextSize) / stackAlignmentRegisters()]);
+    }
+
+    CodeLocationLabel* result = returnPCs.get();
+
+    {
+        ConcurrentJITLocker locker(m_lock);
+        m_returnPCArrays.append(WTF::move(returnPCs));
+        m_refs.append(FINALIZE_CODE(linkBuffer, ("Arity check fail return thunks for up to numArgs = %u", numExpectedArgumentsIncludingThis)));
+        m_nextSize = numExpectedArgumentsIncludingThis + stackAlignmentRegisters();
+    }
+    
+    return result;
+}
+
+CodeLocationLabel ArityCheckFailReturnThunks::returnPCFor(VM& vm, unsigned slotsToAdd)
+{
+    return returnPCsFor(vm, slotsToAdd)[slotsToAdd / stackAlignmentRegisters()];
+}
+
+} // namespace JSC
+
+#endif // ENABLE(JIT)
+