[llvm] 1e77b3a - [MSAN] Allow inserting array checks
Gui Andrade via llvm-commits
llvm-commits at lists.llvm.org
Fri Jul 24 13:13:20 PDT 2020
Author: Gui Andrade
Date: 2020-07-24T20:12:58Z
New Revision: 1e77b3af125e4d1ba79e5d502b959d49f3addef9
URL: https://github.com/llvm/llvm-project/commit/1e77b3af125e4d1ba79e5d502b959d49f3addef9
DIFF: https://github.com/llvm/llvm-project/commit/1e77b3af125e4d1ba79e5d502b959d49f3addef9.diff
LOG: [MSAN] Allow inserting array checks
Flattens arrays by ORing together all their elements.
Differential Revision: https://reviews.llvm.org/D84446
Added:
llvm/test/Instrumentation/MemorySanitizer/check-array.ll
Modified:
llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
Removed:
################################################################################
diff --git a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
index f4f62a31d89e..427abde4277d 100644
--- a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
@@ -1149,36 +1149,30 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
const DataLayout &DL = F.getParent()->getDataLayout();
const Align OriginAlignment = std::max(kMinOriginAlignment, Alignment);
unsigned StoreSize = DL.getTypeStoreSize(Shadow->getType());
- if (Shadow->getType()->isArrayTy()) {
- paintOrigin(IRB, updateOrigin(Origin, IRB), OriginPtr, StoreSize,
- OriginAlignment);
- } else {
- Value *ConvertedShadow = convertShadowToScalar(Shadow, IRB);
- if (auto *ConstantShadow = dyn_cast<Constant>(ConvertedShadow)) {
- if (ClCheckConstantShadow && !ConstantShadow->isZeroValue())
- paintOrigin(IRB, updateOrigin(Origin, IRB), OriginPtr, StoreSize,
- OriginAlignment);
- return;
- }
-
- unsigned TypeSizeInBits =
- DL.getTypeSizeInBits(ConvertedShadow->getType());
- unsigned SizeIndex = TypeSizeToSizeIndex(TypeSizeInBits);
- if (AsCall && SizeIndex < kNumberOfAccessSizes && !MS.CompileKernel) {
- FunctionCallee Fn = MS.MaybeStoreOriginFn[SizeIndex];
- Value *ConvertedShadow2 = IRB.CreateZExt(
- ConvertedShadow, IRB.getIntNTy(8 * (1 << SizeIndex)));
- IRB.CreateCall(Fn, {ConvertedShadow2,
- IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy()),
- Origin});
- } else {
- Value *Cmp = convertToBool(ConvertedShadow, IRB, "_mscmp");
- Instruction *CheckTerm = SplitBlockAndInsertIfThen(
- Cmp, &*IRB.GetInsertPoint(), false, MS.OriginStoreWeights);
- IRBuilder<> IRBNew(CheckTerm);
- paintOrigin(IRBNew, updateOrigin(Origin, IRBNew), OriginPtr, StoreSize,
+ Value *ConvertedShadow = convertShadowToScalar(Shadow, IRB);
+ if (auto *ConstantShadow = dyn_cast<Constant>(ConvertedShadow)) {
+ if (ClCheckConstantShadow && !ConstantShadow->isZeroValue())
+ paintOrigin(IRB, updateOrigin(Origin, IRB), OriginPtr, StoreSize,
OriginAlignment);
- }
+ return;
+ }
+
+ unsigned TypeSizeInBits = DL.getTypeSizeInBits(ConvertedShadow->getType());
+ unsigned SizeIndex = TypeSizeToSizeIndex(TypeSizeInBits);
+ if (AsCall && SizeIndex < kNumberOfAccessSizes && !MS.CompileKernel) {
+ FunctionCallee Fn = MS.MaybeStoreOriginFn[SizeIndex];
+ Value *ConvertedShadow2 =
+ IRB.CreateZExt(ConvertedShadow, IRB.getIntNTy(8 * (1 << SizeIndex)));
+ IRB.CreateCall(Fn,
+ {ConvertedShadow2,
+ IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy()), Origin});
+ } else {
+ Value *Cmp = convertToBool(ConvertedShadow, IRB, "_mscmp");
+ Instruction *CheckTerm = SplitBlockAndInsertIfThen(
+ Cmp, &*IRB.GetInsertPoint(), false, MS.OriginStoreWeights);
+ IRBuilder<> IRBNew(CheckTerm);
+ paintOrigin(IRBNew, updateOrigin(Origin, IRBNew), OriginPtr, StoreSize,
+ OriginAlignment);
}
}
@@ -1410,12 +1404,31 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
return Aggregator;
}
+ // Extract combined shadow of array elements
+ Value *collapseArrayShadow(ArrayType *Array, Value *Shadow,
+ IRBuilder<> &IRB) {
+ if (!Array->getNumElements())
+ return IRB.getIntN(/* width */ 1, /* value */ 0);
+
+ Value *FirstItem = IRB.CreateExtractValue(Shadow, 0);
+ Value *Aggregator = convertShadowToScalar(FirstItem, IRB);
+
+ for (unsigned Idx = 1; Idx < Array->getNumElements(); Idx++) {
+ Value *ShadowItem = IRB.CreateExtractValue(Shadow, Idx);
+ Value *ShadowInner = convertShadowToScalar(ShadowItem, IRB);
+ Aggregator = IRB.CreateOr(Aggregator, ShadowInner);
+ }
+ return Aggregator;
+ }
+
/// Convert a shadow value to it's flattened variant. The resulting
/// shadow may not necessarily have the same bit width as the input
/// value, but it will always be comparable to zero.
Value *convertShadowToScalar(Value *V, IRBuilder<> &IRB) {
if (StructType *Struct = dyn_cast<StructType>(V->getType()))
return collapseStructShadow(Struct, V, IRB);
+ if (ArrayType *Array = dyn_cast<ArrayType>(V->getType()))
+ return collapseArrayShadow(Array, V, IRB);
Type *Ty = V->getType();
Type *NoVecTy = getShadowTyNoVec(Ty);
if (Ty == NoVecTy) return V;
@@ -1765,10 +1778,10 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
if (!InsertChecks) return;
#ifndef NDEBUG
Type *ShadowTy = Shadow->getType();
- assert(
- (isa<IntegerType>(ShadowTy) || isa<VectorType>(ShadowTy) ||
- isa<StructType>(ShadowTy)) &&
- "Can only insert checks for integer, vector, and struct shadow types");
+ assert((isa<IntegerType>(ShadowTy) || isa<VectorType>(ShadowTy) ||
+ isa<StructType>(ShadowTy) || isa<ArrayType>(ShadowTy)) &&
+ "Can only insert checks for integer, vector, and aggregate shadow "
+ "types");
#endif
InstrumentationList.push_back(
ShadowOriginAndInsertPoint(Shadow, Origin, OrigIns));
diff --git a/llvm/test/Instrumentation/MemorySanitizer/check-array.ll b/llvm/test/Instrumentation/MemorySanitizer/check-array.ll
new file mode 100644
index 000000000000..6d1e517a186d
--- /dev/null
+++ b/llvm/test/Instrumentation/MemorySanitizer/check-array.ll
@@ -0,0 +1,19 @@
+; RUN: opt < %s -msan-eager-checks -msan-check-access-address=0 -msan-track-origins=1 -S -passes='module(msan-module),function(msan)' 2>&1 | \
+; RUN: FileCheck -allow-deprecated-dag-overlap -check-prefixes=CHECK,CHECK-ORIGINS %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-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define noundef [2 x i24] @check_array([2 x i24]* %p) sanitize_memory {
+; CHECK: @check_array([2 x i24]* [[P:%.*]])
+; CHECK: [[O:%.*]] = load [2 x i24], [2 x i24]* [[P]]
+ %o = load [2 x i24], [2 x i24]* %p
+; CHECK: [[FIELD0:%.+]] = extractvalue [2 x i24] %_msld, 0
+; CHECK: [[FIELD1:%.+]] = extractvalue [2 x i24] %_msld, 1
+; CHECK: [[F1_OR:%.+]] = or i24 [[FIELD0]], [[FIELD1]]
+; CHECK: %_mscmp = icmp ne i24 [[F1_OR]], 0
+; CHECK: br i1 %_mscmp
+; CHECK: call void @__msan_warning
+; CHECK: ret [2 x i24] [[O]]
+ ret [2 x i24] %o
+}
More information about the llvm-commits
mailing list