X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FAnalysis%2FLint.cpp;h=971065f8d47d8c423b849b40c4bfb5b3b1f37464;hb=25101bb2a799a36be9f077ee2fc2dcf0df2b6efb;hp=e5e7cd38576fc56f6133c507f3e3b66e989bd006;hpb=d261dc650a01ac5c51ab10f97f1e35aa6a770721;p=oota-llvm.git

diff --git a/lib/Analysis/Lint.cpp b/lib/Analysis/Lint.cpp
index e5e7cd38576..971065f8d47 100644
--- a/lib/Analysis/Lint.cpp
+++ b/lib/Analysis/Lint.cpp
@@ -44,6 +44,7 @@
 #include "llvm/Analysis/ValueTracking.h"
 #include "llvm/Assembly/Writer.h"
 #include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetLibraryInfo.h"
 #include "llvm/Pass.h"
 #include "llvm/PassManager.h"
 #include "llvm/IntrinsicInst.h"
@@ -71,7 +72,7 @@ namespace {
     void visitCallSite(CallSite CS);
     void visitMemoryReference(Instruction &I, Value *Ptr,
                               uint64_t Size, unsigned Align,
-                              const Type *Ty, unsigned Flags);
+                              Type *Ty, unsigned Flags);
 
     void visitCallInst(CallInst &I);
     void visitInvokeInst(InvokeInst &I);
@@ -103,6 +104,7 @@ namespace {
     AliasAnalysis *AA;
     DominatorTree *DT;
     TargetData *TD;
+    TargetLibraryInfo *TLI;
 
     std::string Messages;
     raw_string_ostream MessagesStr;
@@ -117,6 +119,7 @@ namespace {
     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
       AU.setPreservesAll();
       AU.addRequired<AliasAnalysis>();
+      AU.addRequired<TargetLibraryInfo>();
       AU.addRequired<DominatorTree>();
     }
     virtual void print(raw_ostream &O, const Module *M) const {}
@@ -149,6 +152,7 @@ namespace {
 char Lint::ID = 0;
 INITIALIZE_PASS_BEGIN(Lint, "lint", "Statically lint-checks LLVM IR",
                       false, true)
+INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfo)
 INITIALIZE_PASS_DEPENDENCY(DominatorTree)
 INITIALIZE_AG_DEPENDENCY(AliasAnalysis)
 INITIALIZE_PASS_END(Lint, "lint", "Statically lint-checks LLVM IR",
@@ -174,6 +178,7 @@ bool Lint::runOnFunction(Function &F) {
   AA = &getAnalysis<AliasAnalysis>();
   DT = &getAnalysis<DominatorTree>();
   TD = getAnalysisIfAvailable<TargetData>();
+  TLI = &getAnalysis<TargetLibraryInfo>();
   visit(F);
   dbgs() << MessagesStr.str();
   Messages.clear();
@@ -201,7 +206,7 @@ void Lint::visitCallSite(CallSite CS) {
             "Undefined behavior: Caller and callee calling convention differ",
             &I);
 
-    const FunctionType *FT = F->getFunctionType();
+    FunctionType *FT = F->getFunctionType();
     unsigned NumActualArgs = unsigned(CS.arg_end()-CS.arg_begin());
 
     Assert1(FT->isVarArg() ?
@@ -226,20 +231,21 @@ void Lint::visitCallSite(CallSite CS) {
                 "Undefined behavior: Call argument type mismatches "
                 "callee parameter type", &I);
 
-        // Check that noalias arguments don't alias other arguments. The
-        // AliasAnalysis API isn't expressive enough for what we really want
-        // to do. Known partial overlap is not distinguished from the case
-        // where nothing is known.
+        // Check that noalias arguments don't alias other arguments. This is
+        // not fully precise because we don't know the sizes of the dereferenced
+        // memory regions.
         if (Formal->hasNoAliasAttr() && Actual->getType()->isPointerTy())
           for (CallSite::arg_iterator BI = CS.arg_begin(); BI != AE; ++BI)
-            Assert1(AI == BI ||
-                    !(*BI)->getType()->isPointerTy() ||
-                    AA->alias(*AI, *BI) != AliasAnalysis::MustAlias,
-                    "Unusual: noalias argument aliases another argument", &I);
+            if (AI != BI && (*BI)->getType()->isPointerTy()) {
+              AliasAnalysis::AliasResult Result = AA->alias(*AI, *BI);
+              Assert1(Result != AliasAnalysis::MustAlias &&
+                      Result != AliasAnalysis::PartialAlias,
+                      "Unusual: noalias argument aliases another argument", &I);
+            }
 
         // Check that an sret argument points to valid memory.
         if (Formal->hasStructRetAttr() && Actual->getType()->isPointerTy()) {
-          const Type *Ty =
+          Type *Ty =
             cast<PointerType>(Formal->getType())->getElementType();
           visitMemoryReference(I, Actual, AA->getTypeStoreSize(Ty),
                                TD ? TD->getABITypeAlignment(Ty) : 0,
@@ -363,7 +369,7 @@ void Lint::visitReturnInst(ReturnInst &I) {
 // TODO: Check readnone/readonly function attributes.
 void Lint::visitMemoryReference(Instruction &I,
                                 Value *Ptr, uint64_t Size, unsigned Align,
-                                const Type *Ty, unsigned Flags) {
+                                Type *Ty, unsigned Flags) {
   // If no memory is being referenced, it doesn't matter if the pointer
   // is valid.
   if (Size == 0)
@@ -566,7 +572,7 @@ Value *Lint::findValueImpl(Value *V, bool OffsetOk,
   // TODO: Look through eliminable cast pairs.
   // TODO: Look through calls with unique return values.
   // TODO: Look through vector insert/extract/shuffle.
-  V = OffsetOk ? V->getUnderlyingObject() : V->stripPointerCasts();
+  V = OffsetOk ? GetUnderlyingObject(V, TD) : V->stripPointerCasts();
   if (LoadInst *L = dyn_cast<LoadInst>(V)) {
     BasicBlock::iterator BBI = L;
     BasicBlock *BB = L->getParent();
@@ -583,15 +589,15 @@ Value *Lint::findValueImpl(Value *V, bool OffsetOk,
     }
   } else if (PHINode *PN = dyn_cast<PHINode>(V)) {
     if (Value *W = PN->hasConstantValue())
-      return findValueImpl(W, OffsetOk, Visited);
+      if (W != V)
+        return findValueImpl(W, OffsetOk, Visited);
   } else if (CastInst *CI = dyn_cast<CastInst>(V)) {
     if (CI->isNoopCast(TD ? TD->getIntPtrType(V->getContext()) :
                             Type::getInt64Ty(V->getContext())))
       return findValueImpl(CI->getOperand(0), OffsetOk, Visited);
   } else if (ExtractValueInst *Ex = dyn_cast<ExtractValueInst>(V)) {
     if (Value *W = FindInsertedValue(Ex->getAggregateOperand(),
-                                     Ex->idx_begin(),
-                                     Ex->idx_end()))
+                                     Ex->getIndices()))
       if (W != V)
         return findValueImpl(W, OffsetOk, Visited);
   } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
@@ -604,10 +610,8 @@ Value *Lint::findValueImpl(Value *V, bool OffsetOk,
                                     Type::getInt64Ty(V->getContext())))
         return findValueImpl(CE->getOperand(0), OffsetOk, Visited);
     } else if (CE->getOpcode() == Instruction::ExtractValue) {
-      const SmallVector<unsigned, 4> &Indices = CE->getIndices();
-      if (Value *W = FindInsertedValue(CE->getOperand(0),
-                                       Indices.begin(),
-                                       Indices.end()))
+      ArrayRef<unsigned> Indices = CE->getIndices();
+      if (Value *W = FindInsertedValue(CE->getOperand(0), Indices))
         if (W != V)
           return findValueImpl(W, OffsetOk, Visited);
     }
@@ -615,10 +619,10 @@ Value *Lint::findValueImpl(Value *V, bool OffsetOk,
 
   // As a last resort, try SimplifyInstruction or constant folding.
   if (Instruction *Inst = dyn_cast<Instruction>(V)) {
-    if (Value *W = SimplifyInstruction(Inst, TD, DT))
+    if (Value *W = SimplifyInstruction(Inst, TD, TLI, DT))
       return findValueImpl(W, OffsetOk, Visited);
   } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
-    if (Value *W = ConstantFoldConstantExpression(CE, TD))
+    if (Value *W = ConstantFoldConstantExpression(CE, TD, TLI))
       if (W != V)
         return findValueImpl(W, OffsetOk, Visited);
   }