From: Nuno Lopes Date: Wed, 25 Jul 2012 17:29:22 +0000 (+0000) Subject: MemoryBuiltins: add support to determine the size of strdup'ed non-constant strings X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=e3094283e38d9e6f6a4a7a14a3a5d0f2af67d5d5;p=oota-llvm.git MemoryBuiltins: add support to determine the size of strdup'ed non-constant strings git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160742 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/include/llvm/Analysis/MemoryBuiltins.h b/include/llvm/Analysis/MemoryBuiltins.h index e674e74520d..76840829ad2 100644 --- a/include/llvm/Analysis/MemoryBuiltins.h +++ b/include/llvm/Analysis/MemoryBuiltins.h @@ -201,6 +201,7 @@ class ObjectSizeOffsetEvaluator typedef SmallPtrSet PtrSetTy; const TargetData *TD; + const TargetLibraryInfo *TLI; LLVMContext &Context; BuilderTy Builder; ObjectSizeOffsetVisitor Visitor; @@ -215,7 +216,8 @@ class ObjectSizeOffsetEvaluator SizeOffsetEvalType compute_(Value *V); public: - ObjectSizeOffsetEvaluator(const TargetData *TD, LLVMContext &Context); + ObjectSizeOffsetEvaluator(const TargetData *TD, const TargetLibraryInfo *TLI, + LLVMContext &Context); SizeOffsetEvalType compute(Value *V); bool knownSize(SizeOffsetEvalType SizeOffset) { diff --git a/lib/Analysis/MemoryBuiltins.cpp b/lib/Analysis/MemoryBuiltins.cpp index 4833b5212be..21417781bd6 100644 --- a/lib/Analysis/MemoryBuiltins.cpp +++ b/lib/Analysis/MemoryBuiltins.cpp @@ -26,6 +26,7 @@ #include "llvm/Support/MathExtras.h" #include "llvm/Support/raw_ostream.h" #include "llvm/Target/TargetData.h" +#include "llvm/Transforms/Utils/BuildLibCalls.h" #include "llvm/Transforms/Utils/Local.h" using namespace llvm; @@ -448,11 +449,9 @@ SizeOffsetType ObjectSizeOffsetVisitor::visitCallSite(CallSite CS) { return std::make_pair(Size, Zero); // TODO: handle more standard functions (+ wchar cousins): - // - strdup / strndup // - strcpy / strncpy // - strcat / strncat // - memcpy / memmove - // - strcat / strncat // - memset } @@ -524,8 +523,9 @@ SizeOffsetType ObjectSizeOffsetVisitor::visitInstruction(Instruction &I) { ObjectSizeOffsetEvaluator::ObjectSizeOffsetEvaluator(const TargetData *TD, + const TargetLibraryInfo *TLI, LLVMContext &Context) -: TD(TD), Context(Context), Builder(Context, TargetFolder(TD)), +: TD(TD), TLI(TLI), Context(Context), Builder(Context, TargetFolder(TD)), Visitor(TD, Context) { IntTy = TD->getIntPtrType(Context); Zero = ConstantInt::get(IntTy, 0); @@ -619,8 +619,21 @@ SizeOffsetEvalType ObjectSizeOffsetEvaluator::visitCallSite(CallSite CS) { // handle strdup-like functions separately if (FnData->AllocTy == StrDupLike) { - // TODO - return unknown(); + IRBuilder<> StdBuilder(Builder.GetInsertPoint()); + Value *Size; + + // strdup(str): size = strlen(str)+1 + if (FnData->FstParam < 0) + Size = EmitStrLen(CS.getArgument(0), StdBuilder, TD, TLI); + else + // strndup(str, maxlen): size = strnlen(str, maxlen)+1 + Size = EmitStrNLen(CS.getArgument(0), CS.getArgument(FnData->FstParam), + StdBuilder, TD, TLI); + if (!Size) + return unknown(); + Builder.SetInsertPoint(StdBuilder.GetInsertPoint()); + Size = Builder.CreateNUWAdd(Size, ConstantInt::get(IntTy, 1)); + return std::make_pair(Size, Zero); } Value *FirstArg = CS.getArgument(FnData->FstParam); @@ -634,11 +647,9 @@ SizeOffsetEvalType ObjectSizeOffsetEvaluator::visitCallSite(CallSite CS) { return std::make_pair(Size, Zero); // TODO: handle more standard functions (+ wchar cousins): - // - strdup / strndup // - strcpy / strncpy // - strcat / strncat // - memcpy / memmove - // - strcat / strncat // - memset } diff --git a/lib/Transforms/Instrumentation/BoundsChecking.cpp b/lib/Transforms/Instrumentation/BoundsChecking.cpp index 09e0f144512..b209fff61da 100644 --- a/lib/Transforms/Instrumentation/BoundsChecking.cpp +++ b/lib/Transforms/Instrumentation/BoundsChecking.cpp @@ -24,6 +24,7 @@ #include "llvm/Support/TargetFolder.h" #include "llvm/Support/raw_ostream.h" #include "llvm/Target/TargetData.h" +#include "llvm/Target/TargetLibraryInfo.h" #include "llvm/Transforms/Instrumentation.h" using namespace llvm; @@ -48,6 +49,7 @@ namespace { virtual void getAnalysisUsage(AnalysisUsage &AU) const { AU.addRequired(); + AU.addRequired(); } private: @@ -166,11 +168,12 @@ bool BoundsChecking::instrument(Value *Ptr, Value *InstVal) { bool BoundsChecking::runOnFunction(Function &F) { TD = &getAnalysis(); + const TargetLibraryInfo *TLI = &getAnalysis(); TrapBB = 0; BuilderTy TheBuilder(F.getContext(), TargetFolder(TD)); Builder = &TheBuilder; - ObjectSizeOffsetEvaluator TheObjSizeEval(TD, F.getContext()); + ObjectSizeOffsetEvaluator TheObjSizeEval(TD, TLI, F.getContext()); ObjSizeEval = &TheObjSizeEval; // check HANDLE_MEMORY_INST in include/llvm/Instruction.def for memory diff --git a/test/Instrumentation/BoundsChecking/strings.ll b/test/Instrumentation/BoundsChecking/strings.ll new file mode 100644 index 00000000000..1942d1407b2 --- /dev/null +++ b/test/Instrumentation/BoundsChecking/strings.ll @@ -0,0 +1,31 @@ +; RUN: opt < %s -bounds-checking -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-S128" + +declare noalias i8* @strdup(i8* nocapture) nounwind +declare noalias i8* @strndup(i8* nocapture, i64) nounwind + +; CHECK: @f1 +define i8 @f1(i8* nocapture %str, i8** nocapture %esc) nounwind uwtable ssp { +; CHECK: call i64 @strlen(i8* %str) +; CHECK-NEXT: %1 = add nuw i64 {{.*}}, 1 + %call = tail call i8* @strdup(i8* %str) nounwind + store i8* %call, i8** %esc, align 8 + %arrayidx = getelementptr inbounds i8* %call, i64 3 +; CHECK: sub i64 %1, 3 + %1 = load i8* %arrayidx, align 1 + ret i8 %1 +; CHECK: call void @llvm.trap +} + +; CHECK: @f2 +define i8 @f2(i8* nocapture %str, i8** nocapture %esc, i64 %limit) nounwind uwtable ssp { +; CHECK: call i64 @strnlen(i8* %str, i64 %limit) +; CHECK-NEXT: %1 = add nuw i64 {{.*}}, 1 + %call = tail call i8* @strndup(i8* %str, i64 %limit) nounwind + store i8* %call, i8** %esc, align 8 + %arrayidx = getelementptr inbounds i8* %call, i64 3 +; CHECK: sub i64 %1, 3 + %1 = load i8* %arrayidx, align 1 + ret i8 %1 +; CHECK: call void @llvm.trap +}