Rename doesNotReadMemory to onlyWritesMemory globally [NFC]

The naming has come up as a source of confusion in several recent reviews.  onlyWritesMemory is consist with onlyReadsMemory which we use for the corresponding readonly case as well.

llvm/include/llvm/Analysis/AliasAnalysis.h

@@ -678,7 +678,7 @@ public:
 
   /// Checks if functions with the specified behavior are known to only write
   /// memory (or not access memory at all).
-  static bool doesNotReadMemory(FunctionModRefBehavior MRB) {
+  static bool onlyWritesMemory(FunctionModRefBehavior MRB) {
     return !isRefSet(createModRefInfo(MRB));
   }
 

llvm/include/llvm/IR/Function.h

@@ -509,10 +509,10 @@ public:
   }
 
   /// Determine if the function does not access or only writes memory.
-  bool doesNotReadMemory() const {
+  bool onlyWritesMemory() const {
     return doesNotAccessMemory() || hasFnAttribute(Attribute::WriteOnly);
   }
-  void setDoesNotReadMemory() {
+  void setOnlyWritesMemory() {
     addFnAttr(Attribute::WriteOnly);
   }
 

llvm/include/llvm/IR/InstrTypes.h

@@ -1717,7 +1717,7 @@ public:
 
   // FIXME: Once this API is no longer duplicated in `CallSite`, rename this to
   // better indicate that this may return a conservative answer.
-  bool doesNotReadMemory(unsigned OpNo) const {
+  bool onlyWritesMemory(unsigned OpNo) const {
     return dataOperandHasImpliedAttr(OpNo, Attribute::WriteOnly) ||
            dataOperandHasImpliedAttr(OpNo, Attribute::ReadNone);
   }
@@ -1824,10 +1824,10 @@ public:
   void setOnlyReadsMemory() { addFnAttr(Attribute::ReadOnly); }
 
   /// Determine if the call does not access or only writes memory.
-  bool doesNotReadMemory() const {
+  bool onlyWritesMemory() const {
     return doesNotAccessMemory() || hasFnAttr(Attribute::WriteOnly);
   }
-  void setDoesNotReadMemory() { addFnAttr(Attribute::WriteOnly); }
+  void setOnlyWritesMemory() { addFnAttr(Attribute::WriteOnly); }
 
   /// Determine if the call can access memmory only using pointers based
   /// on its arguments.

llvm/lib/Analysis/AliasAnalysis.cpp

@@ -242,7 +242,7 @@ ModRefInfo AAResults::getModRefInfo(const CallBase *Call,
 
   if (onlyReadsMemory(MRB))
     Result = clearMod(Result);
-  else if (doesNotReadMemory(MRB))
+  else if (onlyWritesMemory(MRB))
     Result = clearRef(Result);
 
   if (onlyAccessesArgPointees(MRB) || onlyAccessesInaccessibleOrArgMem(MRB)) {
@@ -320,7 +320,7 @@ ModRefInfo AAResults::getModRefInfo(const CallBase *Call1,
   // from Call1 reading memory written by Call2.
   if (onlyReadsMemory(Call1B))
     Result = clearMod(Result);
-  else if (doesNotReadMemory(Call1B))
+  else if (onlyWritesMemory(Call1B))
     Result = clearRef(Result);
 
   // If Call2 only access memory through arguments, accumulate the mod/ref

llvm/lib/Analysis/BasicAliasAnalysis.cpp

@@ -779,7 +779,7 @@ FunctionModRefBehavior BasicAAResult::getModRefBehavior(const CallBase *Call) {
   // than that.
   if (Call->onlyReadsMemory())
     Min = FMRB_OnlyReadsMemory;
-  else if (Call->doesNotReadMemory())
+  else if (Call->onlyWritesMemory())
     Min = FMRB_OnlyWritesMemory;
 
   if (Call->onlyAccessesArgMemory())
@@ -812,7 +812,7 @@ FunctionModRefBehavior BasicAAResult::getModRefBehavior(const Function *F) {
   // If the function declares it only reads memory, go with that.
   if (F->onlyReadsMemory())
     Min = FMRB_OnlyReadsMemory;
-  else if (F->doesNotReadMemory())
+  else if (F->onlyWritesMemory())
     Min = FMRB_OnlyWritesMemory;
 
   if (F->onlyAccessesArgMemory())
@@ -972,7 +972,7 @@ ModRefInfo BasicAAResult::getModRefInfo(const CallBase *Call,
         continue;
       }
       // Operand aliases 'Object' but call only writes into it.
-      if (Call->doesNotReadMemory(OperandNo)) {
+      if (Call->onlyWritesMemory(OperandNo)) {
         Result = setMod(Result);
         continue;
       }

llvm/lib/IR/Instruction.cpp

@@ -585,7 +585,7 @@ bool Instruction::mayReadFromMemory() const {
   case Instruction::Call:
   case Instruction::Invoke:
   case Instruction::CallBr:
-    return !cast<CallBase>(this)->doesNotReadMemory();
+    return !cast<CallBase>(this)->onlyWritesMemory();
   case Instruction::Store:
     return !cast<StoreInst>(this)->isUnordered();
   }

llvm/lib/Transforms/IPO/FunctionAttrs.cpp

@@ -133,7 +133,7 @@ static MemoryAccessKind checkFunctionMemoryAccess(Function &F, bool ThisBody,
     if (AliasAnalysis::onlyReadsMemory(MRB))
       return MAK_ReadOnly;
 
-    if (AliasAnalysis::doesNotReadMemory(MRB))
+    if (AliasAnalysis::onlyWritesMemory(MRB))
       return MAK_WriteOnly;
 
     // Conservatively assume it reads and writes to memory.
@@ -295,7 +295,7 @@ static void addReadAttrs(const SCCNodeSet &SCCNodes, AARGetterT &&AARGetter,
       // No change.
       continue;
 
-    if (F->doesNotReadMemory() && WritesMemory)
+    if (F->onlyWritesMemory() && WritesMemory)
       continue;
 
     Changed.insert(F);

llvm/lib/Transforms/Scalar/LoopInterchange.cpp

@@ -1076,7 +1076,7 @@ bool LoopInterchangeLegality::canInterchangeLoops(unsigned InnerLoopId,
     for (Instruction &I : BB->instructionsWithoutDebug())
       if (CallInst *CI = dyn_cast<CallInst>(&I)) {
         // readnone functions do not prevent interchanging.
-        if (CI->doesNotReadMemory())
+        if (CI->onlyWritesMemory())
           continue;
         LLVM_DEBUG(
             dbgs() << "Loops with call instructions cannot be interchanged "

llvm/lib/Transforms/Utils/BuildLibCalls.cpp

@@ -72,8 +72,8 @@ static bool setOnlyReadsMemory(Function &F) {
   return true;
 }
 
-static bool setDoesNotReadMemory(Function &F) {
-  if (F.doesNotReadMemory()) // writeonly or readnone
+static bool setOnlyWritesMemory(Function &F) {
+  if (F.onlyWritesMemory()) // writeonly or readnone
     return false;
   // Turn readonly and writeonly into readnone.
   if (F.hasFnAttribute(Attribute::ReadOnly)) {
@@ -81,7 +81,7 @@ static bool setDoesNotReadMemory(Function &F) {
     return setDoesNotAccessMemory(F);
   }
   ++NumWriteOnly;
-  F.setDoesNotReadMemory();
+  F.setOnlyWritesMemory();
   return true;
 }
 
@@ -1185,7 +1185,7 @@ bool llvm::inferLibFuncAttributes(Function &F, const TargetLibraryInfo &TLI) {
   case LibFunc_truncl:
     Changed |= setDoesNotThrow(F);
     Changed |= setDoesNotFreeMemory(F);
-    Changed |= setDoesNotReadMemory(F);
+    Changed |= setOnlyWritesMemory(F);
     Changed |= setWillReturn(F);
     return Changed;
   default: