[compiler-rt] ASan Linux MIPS32 support

[jyyou.tw]

Summary

This patch is for compiler-rt

[kcc]

LGTM

[kcc]

LGTM

lib/Transforms/Instrumentation/AddressSanitizer.cpp

 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Module.h"
 #include "llvm/IR/Type.h"
 #include "llvm/InstVisitor.h"
 #include "llvm/Support/CallSite.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/DataTypes.h"
 #include "llvm/Support/Debug.h"
+#include "llvm/Support/Endian.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Support/system_error.h"
 #include "llvm/Transforms/Utils/BasicBlockUtils.h"
 #include "llvm/Transforms/Utils/BlackList.h"
 #include "llvm/Transforms/Utils/Local.h"
 #include "llvm/Transforms/Utils/ModuleUtils.h"
 #include <algorithm>
 #include <string>
 
 using namespace llvm;
 
 static const uint64_t kDefaultShadowScale = 3;
 static const uint64_t kDefaultShadowOffset32 = 1ULL << 29;
 static const uint64_t kDefaultShadowOffset64 = 1ULL << 44;
 static const uint64_t kDefaultShort64bitShadowOffset = 0x7FFF8000;  // < 2G.
 static const uint64_t kPPC64_ShadowOffset64 = 1ULL << 41;
+static const uint64_t kMIPS32_ShadowOffset32 = 0x0aaa8000;
 
 static const size_t kMaxStackMallocSize = 1 << 16;  // 64K
 static const uintptr_t kCurrentStackFrameMagic = 0x41B58AB3;
 static const uintptr_t kRetiredStackFrameMagic = 0x45E0360E;
 
 static const char *kAsanModuleCtorName = "asan.module_ctor";
 static const char *kAsanModuleDtorName = "asan.module_dtor";
 static const int   kAsanCtorAndCtorPriority = 1;

 
 static ShadowMapping getShadowMapping(const Module &M, int LongSize,
                                       bool ZeroBaseShadow) {
   llvm::Triple TargetTriple(M.getTargetTriple());
   bool IsAndroid = TargetTriple.getEnvironment() == llvm::Triple::Android;
   bool IsMacOSX = TargetTriple.getOS() == llvm::Triple::MacOSX;
   bool IsPPC64 = TargetTriple.getArch() == llvm::Triple::ppc64;
   bool IsX86_64 = TargetTriple.getArch() == llvm::Triple::x86_64;
+  bool IsMIPS32 = TargetTriple.getArch() == llvm::Triple::mips ||
+                  TargetTriple.getArch() == llvm::Triple::mipsel;
 
   ShadowMapping Mapping;
 
   // OR-ing shadow offset if more efficient (at least on x86),
   // but on ppc64 we have to use add since the shadow offset is not neccesary
   // 1/8-th of the address space.
   Mapping.OrShadowOffset = !IsPPC64 && !ClShort64BitOffset;
 
   Mapping.Offset = (IsAndroid || ZeroBaseShadow) ? 0 :
-      (LongSize == 32 ? kDefaultShadowOffset32 :
+      (LongSize == 32 ?
+       (IsMIPS32 ? kMIPS32_ShadowOffset32 : kDefaultShadowOffset32) :
        IsPPC64 ? kPPC64_ShadowOffset64 : kDefaultShadowOffset64);
   if (!ZeroBaseShadow && ClShort64BitOffset && IsX86_64 && !IsMacOSX) {
     assert(LongSize == 64);
     Mapping.Offset = kDefaultShort64bitShadowOffset;
   }
   if (!ZeroBaseShadow && ClMappingOffsetLog >= 0) {
     // Zero offset log is the special case.
     Mapping.Offset = (ClMappingOffsetLog == 0) ? 0 : 1ULL << ClMappingOffsetLog;
if (SizeInBytes < AlignedSize) {
                                        (Pos >> Mapping.Scale) - ShadowRZSize));
       size_t AddressableBytes = RedzoneSize() - (AlignedSize - SizeInBytes);
       uint32_t Poison = 0;
       if (DoPoison) {
         PoisonShadowPartialRightRedzone((uint8_t*)&Poison, AddressableBytes,
                                         RedzoneSize(),
                                         1ULL << Mapping.Scale,
                                         kAsanStackPartialRedzoneMagic);
+        if (ASan.TD->isLittleEndian()) {
+          Poison = support::endian::byte_swap<uint32_t, support::little>(Poison);
+        } else {
+          Poison = support::endian::byte_swap<uint32_t, support::big>(Poison);
+        }
       }
       Value *PartialPoison = ConstantInt::get(RZTy, Poison);
       IRB.CreateStore(PartialPoison, IRB.CreateIntToPtr(Ptr, RZPtrTy));
     }
 
     // Poison the full redzone at right.
     Ptr = IRB.CreateAdd(ShadowBase,
                         ConstantInt::get(IntptrTy, Pos >> Mapping.Scale));