[opaque pointer types] Add a FunctionCallee wrapper type, and use it.

The FunctionCallee type is effectively a {FunctionType*,Value*} pair,
and is a useful convenience to enable code to continue passing the
result of getOrInsertFunction() through to EmitCall, even once pointer
types lose their pointee-type.

Then:
- update the CallInst/InvokeInst instruction creation functions to
  take a Callee,
- modify getOrInsertFunction to return FunctionCallee, and
- update all callers appropriately.

One area of particular note is the change to the sanitizer
code. Previously, they had been casting the result of
`getOrInsertFunction` to a `Function*` via
`checkSanitizerInterfaceFunction`, and storing that. That would report
an error if someone had already inserted a function declaraction with
a mismatching signature.

However, in general, LLVM allows for such mismatches, as
`getOrInsertFunction` will automatically insert a bitcast if
needed. As part of this cleanup, cause the sanitizer code to do the
same. (It will call its functions using the expected signature,
however they may have been declared.)

Finally, in a small number of locations, callers of
`getOrInsertFunction` actually were expecting/requiring that a brand
new function was being created. In such cases, I've switched them to
Function::Create instead.

Differential Revision: https://reviews.llvm.org/D57315

llvm-svn: 352791

1 files changed, 68 insertions, 66 deletions

diff --git a/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
index 4be485c50d2..5be13fa745c 100644
--- a/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
@@ -110,25 +110,26 @@ private:
   Type *IntptrTy;
   IntegerType *OrdTy;
   // Callbacks to run-time library are computed in doInitialization.
-  Function *TsanFuncEntry;
-  Function *TsanFuncExit;
-  Function *TsanIgnoreBegin;
-  Function *TsanIgnoreEnd;
+  FunctionCallee TsanFuncEntry;
+  FunctionCallee TsanFuncExit;
+  FunctionCallee TsanIgnoreBegin;
+  FunctionCallee TsanIgnoreEnd;
   // Accesses sizes are powers of two: 1, 2, 4, 8, 16.
   static const size_t kNumberOfAccessSizes = 5;
-  Function *TsanRead[kNumberOfAccessSizes];
-  Function *TsanWrite[kNumberOfAccessSizes];
-  Function *TsanUnalignedRead[kNumberOfAccessSizes];
-  Function *TsanUnalignedWrite[kNumberOfAccessSizes];
-  Function *TsanAtomicLoad[kNumberOfAccessSizes];
-  Function *TsanAtomicStore[kNumberOfAccessSizes];
-  Function *TsanAtomicRMW[AtomicRMWInst::LAST_BINOP + 1][kNumberOfAccessSizes];
-  Function *TsanAtomicCAS[kNumberOfAccessSizes];
-  Function *TsanAtomicThreadFence;
-  Function *TsanAtomicSignalFence;
-  Function *TsanVptrUpdate;
-  Function *TsanVptrLoad;
-  Function *MemmoveFn, *MemcpyFn, *MemsetFn;
+  FunctionCallee TsanRead[kNumberOfAccessSizes];
+  FunctionCallee TsanWrite[kNumberOfAccessSizes];
+  FunctionCallee TsanUnalignedRead[kNumberOfAccessSizes];
+  FunctionCallee TsanUnalignedWrite[kNumberOfAccessSizes];
+  FunctionCallee TsanAtomicLoad[kNumberOfAccessSizes];
+  FunctionCallee TsanAtomicStore[kNumberOfAccessSizes];
+  FunctionCallee TsanAtomicRMW[AtomicRMWInst::LAST_BINOP + 1]
+                              [kNumberOfAccessSizes];
+  FunctionCallee TsanAtomicCAS[kNumberOfAccessSizes];
+  FunctionCallee TsanAtomicThreadFence;
+  FunctionCallee TsanAtomicSignalFence;
+  FunctionCallee TsanVptrUpdate;
+  FunctionCallee TsanVptrLoad;
+  FunctionCallee MemmoveFn, MemcpyFn, MemsetFn;
   Function *TsanCtorFunction;
 };
 
@@ -188,14 +189,14 @@ void ThreadSanitizer::initializeCallbacks(Module &M) {
   Attr = Attr.addAttribute(M.getContext(), AttributeList::FunctionIndex,
                            Attribute::NoUnwind);
   // Initialize the callbacks.
-  TsanFuncEntry = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
-      "__tsan_func_entry", Attr, IRB.getVoidTy(), IRB.getInt8PtrTy()));
-  TsanFuncExit = checkSanitizerInterfaceFunction(
-      M.getOrInsertFunction("__tsan_func_exit", Attr, IRB.getVoidTy()));
-  TsanIgnoreBegin = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
-      "__tsan_ignore_thread_begin", Attr, IRB.getVoidTy()));
-  TsanIgnoreEnd = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
-      "__tsan_ignore_thread_end", Attr, IRB.getVoidTy()));
+  TsanFuncEntry = M.getOrInsertFunction("__tsan_func_entry", Attr,
+                                        IRB.getVoidTy(), IRB.getInt8PtrTy());
+  TsanFuncExit =
+      M.getOrInsertFunction("__tsan_func_exit", Attr, IRB.getVoidTy());
+  TsanIgnoreBegin = M.getOrInsertFunction("__tsan_ignore_thread_begin", Attr,
+                                          IRB.getVoidTy());
+  TsanIgnoreEnd =
+      M.getOrInsertFunction("__tsan_ignore_thread_end", Attr, IRB.getVoidTy());
   OrdTy = IRB.getInt32Ty();
   for (size_t i = 0; i < kNumberOfAccessSizes; ++i) {
     const unsigned ByteSize = 1U << i;
@@ -203,32 +204,30 @@ void ThreadSanitizer::initializeCallbacks(Module &M) {
     std::string ByteSizeStr = utostr(ByteSize);
     std::string BitSizeStr = utostr(BitSize);
     SmallString<32> ReadName("__tsan_read" + ByteSizeStr);
-    TsanRead[i] = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
-        ReadName, Attr, IRB.getVoidTy(), IRB.getInt8PtrTy()));
+    TsanRead[i] = M.getOrInsertFunction(ReadName, Attr, IRB.getVoidTy(),
+                                        IRB.getInt8PtrTy());
 
     SmallString<32> WriteName("__tsan_write" + ByteSizeStr);
-    TsanWrite[i] = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
-        WriteName, Attr, IRB.getVoidTy(), IRB.getInt8PtrTy()));
+    TsanWrite[i] = M.getOrInsertFunction(WriteName, Attr, IRB.getVoidTy(),
+                                         IRB.getInt8PtrTy());
 
     SmallString<64> UnalignedReadName("__tsan_unaligned_read" + ByteSizeStr);
-    TsanUnalignedRead[i] =
-        checkSanitizerInterfaceFunction(M.getOrInsertFunction(
-            UnalignedReadName, Attr, IRB.getVoidTy(), IRB.getInt8PtrTy()));
+    TsanUnalignedRead[i] = M.getOrInsertFunction(
+        UnalignedReadName, Attr, IRB.getVoidTy(), IRB.getInt8PtrTy());
 
     SmallString<64> UnalignedWriteName("__tsan_unaligned_write" + ByteSizeStr);
-    TsanUnalignedWrite[i] =
-        checkSanitizerInterfaceFunction(M.getOrInsertFunction(
-            UnalignedWriteName, Attr, IRB.getVoidTy(), IRB.getInt8PtrTy()));
+    TsanUnalignedWrite[i] = M.getOrInsertFunction(
+        UnalignedWriteName, Attr, IRB.getVoidTy(), IRB.getInt8PtrTy());
 
     Type *Ty = Type::getIntNTy(M.getContext(), BitSize);
     Type *PtrTy = Ty->getPointerTo();
     SmallString<32> AtomicLoadName("__tsan_atomic" + BitSizeStr + "_load");
-    TsanAtomicLoad[i] = checkSanitizerInterfaceFunction(
-        M.getOrInsertFunction(AtomicLoadName, Attr, Ty, PtrTy, OrdTy));
+    TsanAtomicLoad[i] =
+        M.getOrInsertFunction(AtomicLoadName, Attr, Ty, PtrTy, OrdTy);
 
     SmallString<32> AtomicStoreName("__tsan_atomic" + BitSizeStr + "_store");
-    TsanAtomicStore[i] = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
-        AtomicStoreName, Attr, IRB.getVoidTy(), PtrTy, Ty, OrdTy));
+    TsanAtomicStore[i] = M.getOrInsertFunction(
+        AtomicStoreName, Attr, IRB.getVoidTy(), PtrTy, Ty, OrdTy);
 
     for (int op = AtomicRMWInst::FIRST_BINOP;
         op <= AtomicRMWInst::LAST_BINOP; ++op) {
@@ -251,34 +250,34 @@ void ThreadSanitizer::initializeCallbacks(Module &M) {
       else
         continue;
       SmallString<32> RMWName("__tsan_atomic" + itostr(BitSize) + NamePart);
-      TsanAtomicRMW[op][i] = checkSanitizerInterfaceFunction(
-          M.getOrInsertFunction(RMWName, Attr, Ty, PtrTy, Ty, OrdTy));
+      TsanAtomicRMW[op][i] =
+          M.getOrInsertFunction(RMWName, Attr, Ty, PtrTy, Ty, OrdTy);
     }
 
     SmallString<32> AtomicCASName("__tsan_atomic" + BitSizeStr +
                                   "_compare_exchange_val");
-    TsanAtomicCAS[i] = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
-        AtomicCASName, Attr, Ty, PtrTy, Ty, Ty, OrdTy, OrdTy));
+    TsanAtomicCAS[i] = M.getOrInsertFunction(AtomicCASName, Attr, Ty, PtrTy, Ty,
+                                             Ty, OrdTy, OrdTy);
   }
-  TsanVptrUpdate = checkSanitizerInterfaceFunction(
+  TsanVptrUpdate =
       M.getOrInsertFunction("__tsan_vptr_update", Attr, IRB.getVoidTy(),
-                            IRB.getInt8PtrTy(), IRB.getInt8PtrTy()));
-  TsanVptrLoad = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
-      "__tsan_vptr_read", Attr, IRB.getVoidTy(), IRB.getInt8PtrTy()));
-  TsanAtomicThreadFence = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
-      "__tsan_atomic_thread_fence", Attr, IRB.getVoidTy(), OrdTy));
-  TsanAtomicSignalFence = checkSanitizerInterfaceFunction(M.getOrInsertFunction(
-      "__tsan_atomic_signal_fence", Attr, IRB.getVoidTy(), OrdTy));
-
-  MemmoveFn = checkSanitizerInterfaceFunction(
-      M.getOrInsertFunction("memmove", Attr, IRB.getInt8PtrTy(), IRB.getInt8PtrTy(),
-                            IRB.getInt8PtrTy(), IntptrTy));
-  MemcpyFn = checkSanitizerInterfaceFunction(
-      M.getOrInsertFunction("memcpy", Attr, IRB.getInt8PtrTy(), IRB.getInt8PtrTy(),
-                            IRB.getInt8PtrTy(), IntptrTy));
-  MemsetFn = checkSanitizerInterfaceFunction(
-      M.getOrInsertFunction("memset", Attr, IRB.getInt8PtrTy(), IRB.getInt8PtrTy(),
-                            IRB.getInt32Ty(), IntptrTy));
+                            IRB.getInt8PtrTy(), IRB.getInt8PtrTy());
+  TsanVptrLoad = M.getOrInsertFunction("__tsan_vptr_read", Attr,
+                                       IRB.getVoidTy(), IRB.getInt8PtrTy());
+  TsanAtomicThreadFence = M.getOrInsertFunction("__tsan_atomic_thread_fence",
+                                                Attr, IRB.getVoidTy(), OrdTy);
+  TsanAtomicSignalFence = M.getOrInsertFunction("__tsan_atomic_signal_fence",
+                                                Attr, IRB.getVoidTy(), OrdTy);
+
+  MemmoveFn =
+      M.getOrInsertFunction("memmove", Attr, IRB.getInt8PtrTy(),
+                            IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), IntptrTy);
+  MemcpyFn =
+      M.getOrInsertFunction("memcpy", Attr, IRB.getInt8PtrTy(),
+                            IRB.getInt8PtrTy(), IRB.getInt8PtrTy(), IntptrTy);
+  MemsetFn =
+      M.getOrInsertFunction("memset", Attr, IRB.getInt8PtrTy(),
+                            IRB.getInt8PtrTy(), IRB.getInt32Ty(), IntptrTy);
 }
 
 ThreadSanitizer::ThreadSanitizer(Module &M) {
@@ -290,7 +289,9 @@ ThreadSanitizer::ThreadSanitizer(Module &M) {
           /*InitArgs=*/{},
           // This callback is invoked when the functions are created the first
           // time. Hook them into the global ctors list in that case:
-          [&](Function *Ctor, Function *) { appendToGlobalCtors(M, Ctor, 0); });
+          [&](Function *Ctor, FunctionCallee) {
+            appendToGlobalCtors(M, Ctor, 0);
+          });
 }
 
 static bool isVtableAccess(Instruction *I) {
@@ -558,7 +559,7 @@ bool ThreadSanitizer::instrumentLoadOrStore(Instruction *I,
       : cast<LoadInst>(I)->getAlignment();
   Type *OrigTy = cast<PointerType>(Addr->getType())->getElementType();
   const uint32_t TypeSize = DL.getTypeStoreSizeInBits(OrigTy);
-  Value *OnAccessFunc = nullptr;
+  FunctionCallee OnAccessFunc = nullptr;
   if (Alignment == 0 || Alignment >= 8 || (Alignment % (TypeSize / 8)) == 0)
     OnAccessFunc = IsWrite ? TsanWrite[Idx] : TsanRead[Idx];
   else
@@ -658,7 +659,7 @@ bool ThreadSanitizer::instrumentAtomic(Instruction *I, const DataLayout &DL) {
     int Idx = getMemoryAccessFuncIndex(Addr, DL);
     if (Idx < 0)
       return false;
-    Function *F = TsanAtomicRMW[RMWI->getOperation()][Idx];
+    FunctionCallee F = TsanAtomicRMW[RMWI->getOperation()][Idx];
     if (!F)
       return false;
     const unsigned ByteSize = 1U << Idx;
@@ -705,8 +706,9 @@ bool ThreadSanitizer::instrumentAtomic(Instruction *I, const DataLayout &DL) {
     I->eraseFromParent();
   } else if (FenceInst *FI = dyn_cast<FenceInst>(I)) {
     Value *Args[] = {createOrdering(&IRB, FI->getOrdering())};
-    Function *F = FI->getSyncScopeID() == SyncScope::SingleThread ?
-        TsanAtomicSignalFence : TsanAtomicThreadFence;
+    FunctionCallee F = FI->getSyncScopeID() == SyncScope::SingleThread
+                           ? TsanAtomicSignalFence
+                           : TsanAtomicThreadFence;
     CallInst *C = CallInst::Create(F, Args);
     ReplaceInstWithInst(I, C);
   }