[WebAssembly] Use IRBuilder in FixFunctionBitcasts (NFC) (#164268)

Simplifies the code a bit.

Author: kleisauke

llvm/lib/Target/WebAssembly/WebAssemblyFixFunctionBitcasts.cpp

@@ -24,6 +24,7 @@
 
 #include "WebAssembly.h"
 #include "llvm/IR/Constants.h"
+#include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/Module.h"
 #include "llvm/IR/Operator.h"
@@ -114,6 +115,7 @@ static Function *createWrapper(Function *F, FunctionType *Ty) {
   Wrapper->setAttributes(F->getAttributes());
   BasicBlock *BB = BasicBlock::Create(M->getContext(), "body", Wrapper);
   const DataLayout &DL = BB->getDataLayout();
+  IRBuilder<> Builder(BB);
 
   // Determine what arguments to pass.
   SmallVector<Value *, 4> Args;
@@ -140,10 +142,7 @@ static Function *createWrapper(Function *F, FunctionType *Ty) {
       Args.push_back(&*AI);
     } else {
       if (CastInst::isBitOrNoopPointerCastable(ArgType, ParamType, DL)) {
-        Instruction *PtrCast =
-            CastInst::CreateBitOrPointerCast(AI, ParamType, "cast");
-        PtrCast->insertInto(BB, BB->end());
-        Args.push_back(PtrCast);
+        Args.push_back(Builder.CreateBitOrPointerCast(AI, ParamType, "cast"));
       } else if (ArgType->isStructTy() || ParamType->isStructTy()) {
         LLVM_DEBUG(dbgs() << "createWrapper: struct param type in bitcast: "
                           << F->getName() << "\n");
@@ -166,24 +165,19 @@ static Function *createWrapper(Function *F, FunctionType *Ty) {
       for (; AI != AE; ++AI)
         Args.push_back(&*AI);
 
-    CallInst *Call = CallInst::Create(F, Args, "", BB);
+    CallInst *Call = Builder.CreateCall(F, Args);
 
-    Type *ExpectedRtnType = F->getFunctionType()->getReturnType();
-    Type *RtnType = Ty->getReturnType();
     // Determine what value to return.
     if (RtnType->isVoidTy()) {
-      ReturnInst::Create(M->getContext(), BB);
+      Builder.CreateRetVoid();
     } else if (ExpectedRtnType->isVoidTy()) {
       LLVM_DEBUG(dbgs() << "Creating dummy return: " << *RtnType << "\n");
-      ReturnInst::Create(M->getContext(), PoisonValue::get(RtnType), BB);
+      Builder.CreateRet(PoisonValue::get(RtnType));
     } else if (RtnType == ExpectedRtnType) {
-      ReturnInst::Create(M->getContext(), Call, BB);
+      Builder.CreateRet(Call);
     } else if (CastInst::isBitOrNoopPointerCastable(ExpectedRtnType, RtnType,
                                                     DL)) {
-      Instruction *Cast =
-          CastInst::CreateBitOrPointerCast(Call, RtnType, "cast");
-      Cast->insertInto(BB, BB->end());
-      ReturnInst::Create(M->getContext(), Cast, BB);
+      Builder.CreateRet(Builder.CreateBitOrPointerCast(Call, RtnType, "cast"));
     } else if (RtnType->isStructTy() || ExpectedRtnType->isStructTy()) {
       LLVM_DEBUG(dbgs() << "createWrapper: struct return type in bitcast: "
                         << F->getName() << "\n");
@@ -203,9 +197,8 @@ static Function *createWrapper(Function *F, FunctionType *Ty) {
     Wrapper = Function::Create(Ty, Function::PrivateLinkage,
                                F->getName() + "_bitcast_invalid", M);
     Wrapper->setAttributes(F->getAttributes());
-    BasicBlock *BB = BasicBlock::Create(M->getContext(), "body", Wrapper);
-    new UnreachableInst(M->getContext(), BB);
-    Wrapper->setName(F->getName() + "_bitcast_invalid");
+    IRBuilder<> Builder(BasicBlock::Create(M->getContext(), "body", Wrapper));
+    Builder.CreateUnreachable();
   } else if (!WrapperNeeded) {
     LLVM_DEBUG(dbgs() << "createWrapper: no wrapper needed: " << F->getName()
                       << "\n");

llvm/test/CodeGen/WebAssembly/unsupported-function-bitcasts.ll

@@ -10,7 +10,7 @@ declare i32 @has_ptr_arg(ptr)
 
 ; CHECK-LABEL: test_invalid_rtn:
 ; CHECK:      i32.const   $push[[L0:[0-9]+]]=, 0{{$}}
-; CHECK-NEXT: call $push[[L1:[0-9]+]]=, .Lhas_i64_arg_bitcast_invalid.2, $pop[[L0]]{{$}}
+; CHECK-NEXT: call $push[[L1:[0-9]+]]=, .Lhas_i64_arg_bitcast_invalid.1, $pop[[L0]]{{$}}
 ; CHECK-NEXT: drop $pop[[L1]]{{$}}
 ; CHECK-NEXT: i64.const   $push[[L0:[0-9]+]]=, 0{{$}}
 ; CHECK-NEXT: call $push[[L1:[0-9]+]]=, .Lhas_i64_arg_bitcast_invalid, $pop[[L0]]{{$}}
@@ -32,7 +32,7 @@ define void @test_struct_rtn() {
 
 ; CHECK-LABEL: test_invalid_arg:
 ; CHECK:      	i32.const	$push[[L0:[0-9]+]]=, 2{{$}}
-; CHECK-NEXT: 	call	$push[[L1:[0-9]+]]=, .Lhas_ptr_arg_bitcast_invalid.4, $pop[[L0]]{{$}}
+; CHECK-NEXT: 	call	$push[[L1:[0-9]+]]=, .Lhas_ptr_arg_bitcast_invalid.2, $pop[[L0]]{{$}}
 ; CHECK-NEXT: 	drop	$pop[[L1]]{{$}}
 ; CHECK-NEXT: 	i32.const	$push[[L0:[0-9]+]]=, 2{{$}}
 ; CHECK-NEXT: 	call	$push[[L1:[0-9]+]]=, has_ptr_arg, $pop[[L0]]{{$}}
@@ -54,8 +54,8 @@ entry:
 ; CHECK-NEXT:  unreachable
 ; CHECK-NEXT:  end_function
 
-; CHECK-LABEL: .Lhas_i64_arg_bitcast_invalid.2:
-; CHECK-NEXT:  .functype .Lhas_i64_arg_bitcast_invalid.2 (i32) -> (i32)
+; CHECK-LABEL: .Lhas_i64_arg_bitcast_invalid.1:
+; CHECK-NEXT:  .functype .Lhas_i64_arg_bitcast_invalid.1 (i32) -> (i32)
 ; CHECK-NEXT:  unreachable
 ; CHECK-NEXT:  end_function
 
@@ -64,7 +64,7 @@ entry:
 ; CHECK-NEXT: 	unreachable
 ; CHECK-NEXT: 	end_function
 
-; CHECK-LABEL: .Lhas_ptr_arg_bitcast_invalid.4:
-; CHECK-NEXT: 	.functype .Lhas_ptr_arg_bitcast_invalid.4 (i32) -> (i32)
+; CHECK-LABEL: .Lhas_ptr_arg_bitcast_invalid.2:
+; CHECK-NEXT: 	.functype .Lhas_ptr_arg_bitcast_invalid.2 (i32) -> (i32)
 ; CHECK-NEXT: 	unreachable
 ; CHECK-NEXT: 	end_function