lib/System/Memory.cpp

   1 //===- Memory.cpp - Memory Handling Support ---------------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file defines some helpful functions for allocating memory and dealing
  11 // with memory mapped files
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "llvm/System/Memory.h"
  16 #include "llvm/Config/config.h"
  17
  18 namespace llvm {
  19 using namespace sys;
  20 }
  21
  22 // Include the platform-specific parts of this class.
  23 #ifdef LLVM_ON_UNIX
  24 #include "Unix/Memory.inc"
  25 #endif
  26 #ifdef LLVM_ON_WIN32
  27 #include "Win32/Memory.inc"
  28 #endif
  29
  30 extern "C" void sys_icache_invalidate(const void *Addr, size_t len);
  31
  32 /// InvalidateInstructionCache - Before the JIT can run a block of code
  33 /// that has been emitted it must invalidate the instruction cache on some
  34 /// platforms.
  35 void llvm::sys::Memory::InvalidateInstructionCache(const void *Addr,
  36                                                    size_t Len) {
  37
  38 // icache invalidation for PPC and ARM.
  39 #if defined(__APPLE__)
  40
  41 #  if (defined(__POWERPC__) || defined (__ppc__) || \
  42      defined(_POWER) || defined(_ARCH_PPC)) || defined(__arm__)
  43   sys_icache_invalidate(Addr, Len);
  44 #  endif
  45
  46 #else
  47
  48 #  if (defined(__POWERPC__) || defined (__ppc__) || \
  49        defined(_POWER) || defined(_ARCH_PPC)) && defined(__GNUC__)
  50   const size_t LineSize = 32;
  51
  52   const intptr_t Mask = ~(LineSize - 1);
  53   const intptr_t StartLine = ((intptr_t) Addr) & Mask;
  54   const intptr_t EndLine = ((intptr_t) Addr + Len + LineSize - 1) & Mask;
  55
  56   for (intptr_t Line = StartLine; Line < EndLine; Line += LineSize)
  57     asm volatile("dcbf 0, %0" : : "r"(Line));
  58   asm volatile("sync");
  59
  60   for (intptr_t Line = StartLine; Line < EndLine; Line += LineSize)
  61     asm volatile("icbi 0, %0" : : "r"(Line));
  62   asm volatile("isync");
  63 #  elif defined(__arm__) && defined(__GNUC__)
  64   // FIXME: Can we safely always call this for __GNUC__ everywhere?
  65   char *Start = (char*) Addr;
  66   char *End = Start + Len;
  67   __clear_cache(Start, End);
  68 #  endif
  69
  70 #endif  // end apple
  71 }