Refactor code to use new attribute getters on CallSite for NoCapture and ByVal.

Suggested in code review by Eli.

That code in InstCombine looks kinda suspicious.

llvm-svn: 145013

include/llvm/Analysis/CaptureTracking.h

@@ -104,7 +104,7 @@ void llvm::PointerMayBeCaptured(const llvm::Value *V, CaptureTracker &Tracker) {
       // (think of self-referential objects).
       CallSite::arg_iterator B = CS.arg_begin(), E = CS.arg_end();
       for (CallSite::arg_iterator A = B; A != E; ++A)
-        if (A->get() == V && !CS.paramHasAttr(A - B + 1, Attribute::NoCapture))
+        if (A->get() == V && !CS.doesNotCapture(A - B))
           // The parameter is not marked 'nocapture' - captured.
           if (Tracker.captured(I))
             return;

include/llvm/Support/CallSite.h

@@ -237,6 +237,16 @@ public:
 #undef CALLSITE_DELEGATE_GETTER
 #undef CALLSITE_DELEGATE_SETTER
 
+  /// @brief Determine whether this argument is not captured.
+  bool doesNotCapture(unsigned ArgNo) const {
+    return paramHasAttr(ArgNo + 1, Attribute::NoCapture);
+  }
+
+  /// @brief Determine whether this argument is passed by value.
+  bool isByValArgument(unsigned ArgNo) const {
+    return paramHasAttr(ArgNo + 1, Attribute::ByVal);
+  }
+
   /// hasArgument - Returns true if this CallSite passes the given Value* as an
   /// argument to the called function.
   bool hasArgument(const Value *Arg) const {

lib/Analysis/BasicAliasAnalysis.cpp

@@ -706,8 +706,7 @@ BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
       // pointer were passed to arguments that were neither of these, then it
       // couldn't be no-capture.
       if (!(*CI)->getType()->isPointerTy() ||
-          (!CS.paramHasAttr(ArgNo+1, Attribute::NoCapture) &&
-           !CS.paramHasAttr(ArgNo+1, Attribute::ByVal)))
+          (!CS.doesNotCapture(ArgNo) && !CS.isByValArgument(ArgNo)))
         continue;
       
       // If this is a no-capture pointer argument, see if we can tell that it

lib/Analysis/MemoryDependenceAnalysis.cpp

@@ -393,8 +393,7 @@ MemoryDependenceAnalysis::getModRefInfo(const Instruction *Inst,
     // pointer were passed to arguments that were neither of these, then it
     // couldn't be no-capture.
     if (!(*CI)->getType()->isPointerTy() ||
-        (!CS.paramHasAttr(ArgNo+1, Attribute::NoCapture) &&
-         !CS.paramHasAttr(ArgNo+1, Attribute::ByVal)))
+        (!CS.doesNotCapture(ArgNo) && !CS.isByValArgument(ArgNo)))
       continue;
 
     // If this is a no-capture pointer argument, see if we can tell that it

lib/Transforms/InstCombine/InstCombineCalls.cpp

@@ -760,7 +760,7 @@ static bool isSafeToEliminateVarargsCast(const CallSite CS,
   // The size of ByVal arguments is derived from the type, so we
   // can't change to a type with a different size.  If the size were
   // passed explicitly we could avoid this check.
-  if (!CS.paramHasAttr(ix, Attribute::ByVal))
+  if (!CS.isByValArgument(ix))
     return true;
 
   Type* SrcTy = 
@@ -960,7 +960,7 @@ Instruction *InstCombiner::visitCallSite(CallSite CS) {
   PointerType *PTy = cast<PointerType>(Callee->getType());
   FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
   if (FTy->isVarArg()) {
-    int ix = FTy->getNumParams() + (isa<InvokeInst>(Callee) ? 3 : 1);
+    int ix = FTy->getNumParams() + (isa<InvokeInst>(Callee) ? 2 : 0);
     // See if we can optimize any arguments passed through the varargs area of
     // the call.
     for (CallSite::arg_iterator I = CS.arg_begin()+FTy->getNumParams(),

lib/Transforms/Scalar/MemCpyOptimizer.cpp

@@ -950,7 +950,7 @@ bool MemCpyOpt::iterateOnFunction(Function &F) {
         RepeatInstruction = processMemMove(M);
       else if (CallSite CS = (Value*)I) {
         for (unsigned i = 0, e = CS.arg_size(); i != e; ++i)
-          if (CS.paramHasAttr(i+1, Attribute::ByVal))
+          if (CS.isByValArgument(i))
             MadeChange |= processByValArgument(CS, i);
       }
 

lib/Transforms/Scalar/ScalarReplAggregates.cpp

@@ -2534,13 +2534,12 @@ isOnlyCopiedFromConstantGlobal(Value *V, MemTransferInst *&TheCopy,
       // ignore it if we know that the value isn't captured.
       unsigned ArgNo = CS.getArgumentNo(UI);
       if (CS.onlyReadsMemory() &&
-          (CS.getInstruction()->use_empty() ||
-           CS.paramHasAttr(ArgNo+1, Attribute::NoCapture)))
+          (CS.getInstruction()->use_empty() || CS.doesNotCapture(ArgNo)))
         continue;
 
       // If this is being passed as a byval argument, the caller is making a
       // copy, so it is only a read of the alloca.
-      if (CS.paramHasAttr(ArgNo+1, Attribute::ByVal))
+      if (CS.isByValArgument(ArgNo))
         continue;
     }
 

lib/Transforms/Utils/InlineFunction.cpp

@@ -987,7 +987,7 @@ bool llvm::InlineFunction(CallSite CS, InlineFunctionInfo &IFI) {
       // by them explicit.  However, we don't do this if the callee is readonly
       // or readnone, because the copy would be unneeded: the callee doesn't
       // modify the struct.
-      if (CalledFunc->paramHasAttr(ArgNo+1, Attribute::ByVal)) {
+      if (CS.isByValArgument(ArgNo)) {
         ActualArg = HandleByValArgument(ActualArg, TheCall, CalledFunc, IFI,
                                         CalledFunc->getParamAlignment(ArgNo+1));