assembler/MaxFrameExtentForSlowPathCall.h

   1 /*
   2  * Copyright (C) 2013 Apple Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #ifndef MaxFrameExtentForSlowPathCall_h
  27 #define MaxFrameExtentForSlowPathCall_h
  28
  29 #include "JSStack.h"
  30 #include "Register.h"
  31 #include "StackAlignment.h"
  32 #include <wtf/Assertions.h>
  33
  34 namespace JSC {
  35
  36 // The maxFrameExtentForSlowPathCall is the max amount of stack space (in bytes)
  37 // that can be used for outgoing args when calling a slow path C function
  38 // from JS code.
  39
  40 #if !ENABLE(JIT)
  41 static const size_t maxFrameExtentForSlowPathCall = 0;
  42
  43 #elif CPU(X86_64) && OS(WINDOWS)
  44 // 4 args in registers, but stack space needs to be allocated for all args.
  45 static const size_t maxFrameExtentForSlowPathCall = 64;
  46
  47 #elif CPU(X86_64)
  48 // All args in registers.
  49 static const size_t maxFrameExtentForSlowPathCall = 0;
  50
  51 #elif CPU(X86)
  52 // 7 args on stack (28 bytes).
  53 static const size_t maxFrameExtentForSlowPathCall = 40;
  54
  55 #elif CPU(ARM64)
  56 // All args in registers.
  57 static const size_t maxFrameExtentForSlowPathCall = 0;
  58
  59 #elif CPU(ARM)
  60 // First four args in registers, remaining 4 args on stack.
  61 static const size_t maxFrameExtentForSlowPathCall = 24;
  62
  63 #elif CPU(SH4)
  64 // First four args in registers, remaining 4 args on stack.
  65 static const size_t maxFrameExtentForSlowPathCall = 24;
  66
  67 #elif CPU(MIPS)
  68 // Though args are in registers, there need to be space on the stack for all args.
  69 static const size_t maxFrameExtentForSlowPathCall = 40;
  70
  71 #else
  72 #error "Unsupported CPU: need value for maxFrameExtentForSlowPathCall"
  73
  74 #endif
  75
  76 COMPILE_ASSERT(!(maxFrameExtentForSlowPathCall % sizeof(Register)), extent_must_be_in_multiples_of_registers);
  77
  78 #if ENABLE(JIT)
  79 // Make sure that cfr - maxFrameExtentForSlowPathCall bytes will make the stack pointer aligned
  80 COMPILE_ASSERT((maxFrameExtentForSlowPathCall % 16) == 16 - sizeof(CallerFrameAndPC), extent_must_align_stack_from_callframe_pointer);
  81 #endif
  82
  83 static const size_t maxFrameExtentForSlowPathCallInRegisters = maxFrameExtentForSlowPathCall / sizeof(Register);
  84
  85 } // namespace JSC
  86
  87 #endif // MaxFrameExtentForSlowPathCall_h
  88