[InstCombine] Don't drop operand bundles

[sanjoy]

lib/Transforms/InstCombine/InstCombineCalls.cpp

2272

This loop is repeated at one other place (InlineFunction, I think). In a separate change, I'll extract this loop out into a helper function.

[majnemer]

LGTM

include/llvm/IR/IRBuilder.h

public:
   }
   /// \brief Create an invoke instruction.
   InvokeInst *CreateInvoke(Value *Callee, BasicBlock *NormalDest,
                            BasicBlock *UnwindDest, ArrayRef<Value *> Args,
                            const Twine &Name = "") {
     return Insert(InvokeInst::Create(Callee, NormalDest, UnwindDest, Args),
                   Name);
   }
+  InvokeInst *CreateInvoke(Value *Callee, BasicBlock *NormalDest,
+                           BasicBlock *UnwindDest, ArrayRef<Value *> Args,
+                           ArrayRef<OperandBundleDef> OpBundles,
+                           const Twine &Name = "") {
+    return Insert(InvokeInst::Create(Callee, NormalDest, UnwindDest, Args,
+                                     OpBundles), Name);
+  }
 
   ResumeInst *CreateResume(Value *Exn) {
     return Insert(ResumeInst::Create(Exn));
   }
 
   CleanupReturnInst *CreateCleanupRet(CleanupPadInst *CleanupPad,
                                       BasicBlock *UnwindBB = nullptr) {
     return Insert(CleanupReturnInst::Create(CleanupPad, UnwindBB));
public:
   //===--------------------------------------------------------------------===//
 
   PHINode *CreatePHI(Type *Ty, unsigned NumReservedValues,
                      const Twine &Name = "") {
     return Insert(PHINode::Create(Ty, NumReservedValues), Name);
   }
 
   CallInst *CreateCall(Value *Callee, ArrayRef<Value *> Args = None,
+                       ArrayRef<OperandBundleDef> OpBundles = None,
                        const Twine &Name = "") {
+    return Insert(CallInst::Create(Callee, Args, OpBundles), Name);
+  }
+  CallInst *CreateCall(Value *Callee, ArrayRef<Value *> Args,
+                       const Twine &Name) {
     return Insert(CallInst::Create(Callee, Args), Name);
   }
 
   CallInst *CreateCall(llvm::FunctionType *FTy, Value *Callee,
                        ArrayRef<Value *> Args, const Twine &Name = "") {
     return Insert(CallInst::Create(FTy, Callee, Args), Name);
   }
 

lib/Transforms/InstCombine/InstCombineCalls.cpp

if (CallerPAL.hasAttributes(AttributeSet::FunctionIndex))
     attrVec.push_back(AttributeSet::get(Callee->getContext(), FnAttrs));
 
   if (NewRetTy->isVoidTy())
     Caller->setName("");   // Void type should not have a name.
 
   const AttributeSet &NewCallerPAL = AttributeSet::get(Callee->getContext(),
                                                        attrVec);
 
+  SmallVector<OperandBundleDef, 1> OpBundles;
+
+  // Convert the operand bundle uses to operand bundle defs.  See InstrTypes.h
+  // for details on how these differ.
+  for (unsigned i = 0, e = CS.getNumOperandBundles(); i != e; ++i)
+    OpBundles.emplace_back(CS.getOperandBundleAt(i));
+
   Instruction *NC;
   if (InvokeInst *II = dyn_cast<InvokeInst>(Caller)) {
-    NC = Builder->CreateInvoke(Callee, II->getNormalDest(),
-                               II->getUnwindDest(), Args);
+    NC = Builder->CreateInvoke(Callee, II->getNormalDest(), II->getUnwindDest(),
+                               Args, OpBundles);
     NC->takeName(II);
     cast<InvokeInst>(NC)->setCallingConv(II->getCallingConv());
     cast<InvokeInst>(NC)->setAttributes(NewCallerPAL);
   } else {
     CallInst *CI = cast<CallInst>(Caller);
-    NC = Builder->CreateCall(Callee, Args);
+    NC = Builder->CreateCall(Callee, Args, OpBundles);
     NC->takeName(CI);
     if (CI->isTailCall())
       cast<CallInst>(NC)->setTailCall();
     cast<CallInst>(NC)->setCallingConv(CI->getCallingConv());
     cast<CallInst>(NC)->setAttributes(NewCallerPAL);
   }
 
   // Insert a cast of the return type as necessary.

test/Transforms/InstCombine/cast-callee-deopt-bundles.ll

+; RUN: opt -instcombine -S < %s | FileCheck %s
+
+declare void @foo(i32)
+
+define void @g() {
+; CHECK-LABEL: @g(
+ entry:
+; CHECK: call void @foo(i32 0) [ "deopt"() ]
+  call void bitcast (void (i32)* @foo to void ()*) ()  [ "deopt"() ]
+  ret void
+}