[llvm] r194780 - Revert "[asan] Poor man's coverage that works with ASan"
Bob Wilson
bob.wilson at apple.com
Thu Nov 14 19:28:22 PST 2013
Author: bwilson
Date: Thu Nov 14 21:28:22 2013
New Revision: 194780
URL: http://llvm.org/viewvc/llvm-project?rev=194780&view=rev
Log:
Revert "[asan] Poor man's coverage that works with ASan"
This reverts commit 194701. Apple's bootstrapped LTO builds have been failing,
and this change (along with compiler-rt 194702-194704) is the only thing on
the blamelist. I will either reappy these changes or help debug the problem,
depending on whether this fixes the buildbots.
Removed:
llvm/trunk/test/Instrumentation/AddressSanitizer/coverage.ll
Modified:
llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp
Modified: llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp?rev=194780&r1=194779&r2=194780&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp (original)
+++ llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp Thu Nov 14 21:28:22 2013
@@ -77,7 +77,6 @@ static const char *const kAsanUnregister
static const char *const kAsanPoisonGlobalsName = "__asan_before_dynamic_init";
static const char *const kAsanUnpoisonGlobalsName = "__asan_after_dynamic_init";
static const char *const kAsanInitName = "__asan_init_v3";
-static const char *const kAsanCovName = "__sanitizer_cov";
static const char *const kAsanHandleNoReturnName = "__asan_handle_no_return";
static const char *const kAsanMappingOffsetName = "__asan_mapping_offset";
static const char *const kAsanMappingScaleName = "__asan_mapping_scale";
@@ -135,8 +134,6 @@ static cl::opt<bool> ClUseAfterReturn("a
// This flag may need to be replaced with -f[no]asan-globals.
static cl::opt<bool> ClGlobals("asan-globals",
cl::desc("Handle global objects"), cl::Hidden, cl::init(true));
-static cl::opt<bool> ClCoverage("asan-coverage",
- cl::desc("ASan coverage"), cl::Hidden, cl::init(false));
static cl::opt<bool> ClInitializers("asan-initialization-order",
cl::desc("Handle C++ initializer order"), cl::Hidden, cl::init(false));
static cl::opt<bool> ClMemIntrin("asan-memintrin",
@@ -327,7 +324,6 @@ struct AddressSanitizer : public Functio
bool LooksLikeCodeInBug11395(Instruction *I);
void FindDynamicInitializers(Module &M);
bool GlobalIsLinkerInitialized(GlobalVariable *G);
- bool InjectCoverage(Function &F);
bool CheckInitOrder;
bool CheckUseAfterReturn;
@@ -343,7 +339,6 @@ struct AddressSanitizer : public Functio
Function *AsanCtorFunction;
Function *AsanInitFunction;
Function *AsanHandleNoReturnFunc;
- Function *AsanCovFunction;
OwningPtr<SpecialCaseList> BL;
// This array is indexed by AccessIsWrite and log2(AccessSize).
Function *AsanErrorCallback[2][kNumberOfAccessSizes];
@@ -1090,8 +1085,6 @@ void AddressSanitizer::initializeCallbac
AsanHandleNoReturnFunc = checkInterfaceFunction(M.getOrInsertFunction(
kAsanHandleNoReturnName, IRB.getVoidTy(), NULL));
- AsanCovFunction = checkInterfaceFunction(M.getOrInsertFunction(
- kAsanCovName, IRB.getVoidTy(), IntptrTy, NULL));
// We insert an empty inline asm after __asan_report* to avoid callback merge.
EmptyAsm = InlineAsm::get(FunctionType::get(IRB.getVoidTy(), false),
StringRef(""), StringRef(""),
@@ -1163,47 +1156,6 @@ bool AddressSanitizer::maybeInsertAsanIn
return false;
}
-// Poor man's coverage that works with ASan.
-// We create a Guard boolean variable with the same linkage
-// as the function and inject this code into the entry block:
-// if (*Guard) {
-// __sanitizer_cov(&F);
-// *Guard = 1;
-// }
-// The accesses to Guard are atomic. The rest of the logic is
-// in __sanitizer_cov (it's fine to call it more than once).
-//
-// This coverage implementation provides very limited data:
-// it only tells if a given function was ever executed.
-// No counters, no per-basic-block or per-edge data.
-// But for many use cases this is what we need and the added slowdown
-// is negligible. This simple implementation will probably be obsoleted
-// by the upcoming Clang-based coverage implementation.
-// By having it here and now we hope to
-// a) get the functionality to users earlier and
-// b) collect usage statistics to help improve Clang coverage design.
-bool AddressSanitizer::InjectCoverage(Function &F) {
- if (!ClCoverage) return false;
- IRBuilder<> IRB(F.getEntryBlock().getFirstInsertionPt());
- Type *Int8Ty = IRB.getInt8Ty();
- GlobalVariable *Guard = new GlobalVariable(
- *F.getParent(), Int8Ty, false, F.getLinkage(),
- Constant::getNullValue(Int8Ty), "__asan_gen_cov_" + F.getName());
- LoadInst *Load = IRB.CreateLoad(Guard);
- Load->setAtomic(Monotonic);
- Load->setAlignment(1);
- Value *Cmp = IRB.CreateICmpEQ(Constant::getNullValue(Int8Ty), Load);
- Instruction *Ins = SplitBlockAndInsertIfThen(cast<Instruction>(Cmp), false);
- IRB.SetInsertPoint(Ins);
- // We pass &F to __sanitizer_cov. We could avoid this and rely on
- // GET_CALLER_PC, but having the PC of the first instruction is just nice.
- IRB.CreateCall(AsanCovFunction, IRB.CreatePointerCast(&F, IntptrTy));
- StoreInst *Store = IRB.CreateStore(ConstantInt::get(Int8Ty, 1), Guard);
- Store->setAtomic(Monotonic);
- Store->setAlignment(1);
- return true;
-}
-
bool AddressSanitizer::runOnFunction(Function &F) {
if (BL->isIn(F)) return false;
if (&F == AsanCtorFunction) return false;
@@ -1299,10 +1251,6 @@ bool AddressSanitizer::runOnFunction(Fun
}
bool res = NumInstrumented > 0 || ChangedStack || !NoReturnCalls.empty();
-
- if (InjectCoverage(F))
- res = true;
-
DEBUG(dbgs() << "ASAN done instrumenting: " << res << " " << F << "\n");
if (ClKeepUninstrumented) {
Removed: llvm/trunk/test/Instrumentation/AddressSanitizer/coverage.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Instrumentation/AddressSanitizer/coverage.ll?rev=194779&view=auto
==============================================================================
--- llvm/trunk/test/Instrumentation/AddressSanitizer/coverage.ll (original)
+++ llvm/trunk/test/Instrumentation/AddressSanitizer/coverage.ll (removed)
@@ -1,13 +0,0 @@
-; RUN: opt < %s -asan -asan-coverage=1 -S | FileCheck %s
-target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
-target triple = "x86_64-unknown-linux-gnu"
-define i32 @foo(i32* %a) sanitize_address {
-entry:
- ret i32 0
-}
-; CHECK: define i32 @foo(i32* %a) #0 {
-; CHECK: %0 = load atomic i8* @__asan_gen_cov_foo monotonic, align 1
-; CHECK: %1 = icmp eq i8 0, %0
-; CHECK: br i1 %1, label %2, label %3
-; CHECK: call void @__sanitizer_cov(i64 ptrtoint (i32 (i32*)* @foo to i64))
-; CHECK: store atomic i8 1, i8* @__asan_gen_cov_foo monotonic, align 1
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