Revert r307342, r307343.

Revert "Copy arguments passed by value into explicit allocas for ASan."
Revert "[asan] Add end-to-end tests for overflows of byval arguments."

Build failure on lldb-x86_64-ubuntu-14.04-buildserver.
Test failure on clang-cmake-aarch64-42vma and sanitizer-x86_64-linux-android.

llvm-svn: 307345

1 files changed, 0 insertions, 37 deletions

diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 5f98cd566f3..184940b7ea5 100644
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -22,11 +22,9 @@
 #include "llvm/ADT/Statistic.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/Triple.h"
-#include "llvm/ADT/Twine.h"
 #include "llvm/Analysis/MemoryBuiltins.h"
 #include "llvm/Analysis/TargetLibraryInfo.h"
 #include "llvm/Analysis/ValueTracking.h"
-#include "llvm/IR/Argument.h"
 #include "llvm/IR/CallSite.h"
 #include "llvm/IR/DIBuilder.h"
 #include "llvm/IR/DataLayout.h"
@@ -194,11 +192,6 @@ static cl::opt<uint32_t> ClMaxInlinePoisoningSize(
 static cl::opt<bool> ClUseAfterReturn("asan-use-after-return",
                                       cl::desc("Check stack-use-after-return"),
                                       cl::Hidden, cl::init(true));
-static cl::opt<bool> ClRedzoneByvalArgs("asan-redzone-byval-args",
-                                        cl::desc("Create redzones for byval "
-                                                 "arguments (extra copy "
-                                                 "required)"), cl::Hidden,
-                                        cl::init(true));
 static cl::opt<bool> ClUseAfterScope("asan-use-after-scope",
                                      cl::desc("Check stack-use-after-scope"),
                                      cl::Hidden, cl::init(false));
@@ -754,9 +747,6 @@ struct FunctionStackPoisoner : public InstVisitor<FunctionStackPoisoner> {
 
   bool runOnFunction() {
     if (!ClStack) return false;
-
-    if (ClRedzoneByvalArgs) copyArgsPassedByValToAllocas();
-
     // Collect alloca, ret, lifetime instructions etc.
     for (BasicBlock *BB : depth_first(&F.getEntryBlock())) visit(*BB);
 
@@ -773,11 +763,6 @@ struct FunctionStackPoisoner : public InstVisitor<FunctionStackPoisoner> {
     return true;
   }
 
-  // Arguments marked with the "byval" attribute are implicitly copied without
-  // using an alloca instruction.  To produce redzones for those arguments, we
-  // copy them a second time into memory allocated with an alloca instruction.
-  void copyArgsPassedByValToAllocas();
-
   // Finds all Alloca instructions and puts
   // poisoned red zones around all of them.
   // Then unpoison everything back before the function returns.
@@ -2543,28 +2528,6 @@ static int StackMallocSizeClass(uint64_t LocalStackSize) {
   llvm_unreachable("impossible LocalStackSize");
 }
 
-void FunctionStackPoisoner::copyArgsPassedByValToAllocas() {
-  BasicBlock &FirstBB = *F.begin();
-  IRBuilder<> IRB(&FirstBB, FirstBB.getFirstInsertionPt());
-  const DataLayout &DL = F.getParent()->getDataLayout();
-  for (Argument &Arg : F.args()) {
-    if (Arg.hasByValAttr()) {
-      Type *Ty = Arg.getType()->getPointerElementType();
-      unsigned Align = Arg.getParamAlignment();
-      if (Align == 0) Align = DL.getABITypeAlignment(Ty);
-
-      const std::string &Name = Arg.hasName() ? Arg.getName().str() :
-          "Arg" + std::to_string(Arg.getArgNo());
-      AllocaInst *AI = IRB.CreateAlloca(Ty, nullptr, Twine(Name) + ".byval");
-      AI->setAlignment(Align);
-      Arg.replaceAllUsesWith(AI);
-
-      uint64_t AllocSize = DL.getTypeAllocSize(Ty);
-      IRB.CreateMemCpy(AI, &Arg, AllocSize, Align);
-    }
-  }
-}
-
 PHINode *FunctionStackPoisoner::createPHI(IRBuilder<> &IRB, Value *Cond,
                                           Value *ValueIfTrue,
                                           Instruction *ThenTerm,