[clang][CodeGen] Remove ptr-to-ptr bitcasts (NFC) (llvm#73020)

Opaque ptr cleanup effort

Author: JOE1994

clang/lib/CodeGen/CGBuiltin.cpp

@@ -5745,12 +5745,8 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
     Address DestAddr = EmitMSVAListRef(E->getArg(0));
     Address SrcAddr = EmitMSVAListRef(E->getArg(1));
 
-    llvm::Type *BPP = Int8PtrPtrTy;
-
-    DestAddr = Address(Builder.CreateBitCast(DestAddr.getPointer(), BPP, "cp"),
-                       Int8PtrTy, DestAddr.getAlignment());
-    SrcAddr = Address(Builder.CreateBitCast(SrcAddr.getPointer(), BPP, "ap"),
-                      Int8PtrTy, SrcAddr.getAlignment());
+    DestAddr = DestAddr.withElementType(Int8PtrTy);
+    SrcAddr = SrcAddr.withElementType(Int8PtrTy);
 
     Value *ArgPtr = Builder.CreateLoad(SrcAddr, "ap.val");
     return RValue::get(Builder.CreateStore(ArgPtr, DestAddr));
@@ -8424,8 +8420,7 @@ Value *CodeGenFunction::EmitARMBuiltinExpr(unsigned BuiltinID,
     }
 
     Value *LdPtr = EmitScalarExpr(E->getArg(0));
-    Value *Val = Builder.CreateCall(F, Builder.CreateBitCast(LdPtr, Int8PtrTy),
-                                    "ldrexd");
+    Value *Val = Builder.CreateCall(F, LdPtr, "ldrexd");
 
     Value *Val0 = Builder.CreateExtractValue(Val, 1);
     Value *Val1 = Builder.CreateExtractValue(Val, 0);
@@ -8483,7 +8478,7 @@ Value *CodeGenFunction::EmitARMBuiltinExpr(unsigned BuiltinID,
 
     Value *Arg0 = Builder.CreateExtractValue(Val, 0);
     Value *Arg1 = Builder.CreateExtractValue(Val, 1);
-    Value *StPtr = Builder.CreateBitCast(EmitScalarExpr(E->getArg(1)), Int8PtrTy);
+    Value *StPtr = EmitScalarExpr(E->getArg(1));
     return Builder.CreateCall(F, {Arg0, Arg1, StPtr}, "strexd");
   }
 

clang/lib/CodeGen/CGStmt.cpp

@@ -1299,8 +1299,7 @@ void CodeGenFunction::EmitReturnStmt(const ReturnStmt &S) {
     SLocPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
     CGM.getSanitizerMetadata()->disableSanitizerForGlobal(SLocPtr);
     assert(ReturnLocation.isValid() && "No valid return location");
-    Builder.CreateStore(Builder.CreateBitCast(SLocPtr, Int8PtrTy),
-                        ReturnLocation);
+    Builder.CreateStore(SLocPtr, ReturnLocation);
   }
 
   // Returning from an outlined SEH helper is UB, and we already warn on it.