webkitgtk-2.16.5HEADwebkitgtk-2.16.5master

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diff --git a/Source/JavaScriptCore/assembler/MaxFrameExtentForSlowPathCall.h b/Source/JavaScriptCore/assembler/MaxFrameExtentForSlowPathCall.h
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+/*
+ * Copyright (C) 2013, 2016 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. 
+ */
+
+#pragma once
+
+#include "Register.h"
+#include "StackAlignment.h"
+#include <wtf/Assertions.h>
+
+namespace JSC {
+
+// The maxFrameExtentForSlowPathCall is the max amount of stack space (in bytes)
+// that can be used for outgoing args when calling a slow path C function
+// from JS code.
+
+#if !ENABLE(JIT)
+static const size_t maxFrameExtentForSlowPathCall = 0;
+
+#elif CPU(X86_64) && OS(WINDOWS)
+// 4 args in registers, but stack space needs to be allocated for all args.
+static const size_t maxFrameExtentForSlowPathCall = 64;
+
+#elif CPU(X86_64)
+// All args in registers.
+static const size_t maxFrameExtentForSlowPathCall = 0;
+
+#elif CPU(X86)
+// 7 args on stack (28 bytes).
+static const size_t maxFrameExtentForSlowPathCall = 40;
+
+#elif CPU(ARM64)
+// All args in registers.
+static const size_t maxFrameExtentForSlowPathCall = 0;
+
+#elif CPU(ARM)
+// First four args in registers, remaining 4 args on stack.
+static const size_t maxFrameExtentForSlowPathCall = 24;
+
+#elif CPU(MIPS)
+// Though args are in registers, there need to be space on the stack for all args.
+static const size_t maxFrameExtentForSlowPathCall = 40;
+
+#else
+#error "Unsupported CPU: need value for maxFrameExtentForSlowPathCall"
+
+#endif
+
+COMPILE_ASSERT(!(maxFrameExtentForSlowPathCall % sizeof(Register)), extent_must_be_in_multiples_of_registers);
+
+#if ENABLE(JIT)
+// Make sure that cfr - maxFrameExtentForSlowPathCall bytes will make the stack pointer aligned
+COMPILE_ASSERT((maxFrameExtentForSlowPathCall % 16) == 16 - sizeof(CallerFrameAndPC), extent_must_align_stack_from_callframe_pointer);
+#endif
+
+static const size_t maxFrameExtentForSlowPathCallInRegisters = maxFrameExtentForSlowPathCall / sizeof(Register);
+
+} // namespace JSC