Build enough support for aggregates to be able to compile this:

void test(int A, _Complex float Y) {
  _Complex float X;
  X = X;

}

llvm-svn: 39669

clang/CodeGen/CGExpr.cpp

@@ -231,7 +231,16 @@ RValue CodeGenFunction::EmitLoadOfLValue(const Expr *E) {
   
   // FIXME: this is silly and obviously wrong for non-scalars.
   assert(!LV.isBitfield());
-  return RValue::get(Builder.CreateLoad(LV.getAddress(), "tmp"));
+  llvm::Value *Ptr = LV.getAddress();
+  const llvm::Type *EltTy =
+    cast<llvm::PointerType>(Ptr->getType())->getElementType();
+  
+  // Simple scalar l-value.
+  if (EltTy->isFirstClassType())
+    return RValue::get(Builder.CreateLoad(Ptr, "tmp"));
+  
+  // Otherwise, we have an aggregate lvalue.
+  return RValue::getAggregate(Ptr);
 }
 
 /// EmitStoreThroughLValue - Store the specified rvalue into the specified
@@ -239,20 +248,43 @@ RValue CodeGenFunction::EmitLoadOfLValue(const Expr *E) {
 /// is 'Ty'.
 void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst, 
                                              QualType Ty) {
-  // FIXME: This is obviously bogus.
   assert(!Dst.isBitfield() && "FIXME: Don't support store to bitfield yet");
-  assert(Src.isScalar() && "FIXME: Don't support store of aggregate yet");
   
-  // TODO: Handle volatility etc.
-  llvm::Value *Addr = Dst.getAddress();
-  const llvm::Type *SrcTy = Src.getVal()->getType();
-  const llvm::Type *AddrTy = 
-    cast<llvm::PointerType>(Addr->getType())->getElementType();
+  llvm::Value *DstAddr = Dst.getAddress();
+  if (Src.isScalar()) {
+    // FIXME: Handle volatility etc.
+    const llvm::Type *SrcTy = Src.getVal()->getType();
+    const llvm::Type *AddrTy = 
+      cast<llvm::PointerType>(DstAddr->getType())->getElementType();
     
-  if (AddrTy != SrcTy)
-    Addr = Builder.CreateBitCast(Addr, llvm::PointerType::get(SrcTy),
-                                 "storetmp");
-  Builder.CreateStore(Src.getVal(), Addr);
+    if (AddrTy != SrcTy)
+      DstAddr = Builder.CreateBitCast(DstAddr, llvm::PointerType::get(SrcTy),
+                                      "storetmp");
+    Builder.CreateStore(Src.getVal(), DstAddr);
+    return;
+  }
+  
+  // Aggregate assignment turns into llvm.memcpy.
+  const llvm::Type *SBP = llvm::PointerType::get(llvm::Type::Int8Ty);
+  llvm::Value *SrcAddr = Src.getAggregateAddr();
+  
+  if (DstAddr->getType() != SBP)
+    DstAddr = Builder.CreateBitCast(DstAddr, SBP, "tmp");
+  if (SrcAddr->getType() != SBP)
+    SrcAddr = Builder.CreateBitCast(SrcAddr, SBP, "tmp");
+
+  unsigned Align = 1;   // FIXME: Compute type alignments.
+  unsigned Size = 1234; // FIXME: Compute type sizes.
+  
+  // FIXME: Handle variable sized types.
+  const llvm::Type *IntPtr = llvm::IntegerType::get(LLVMPointerWidth);
+  llvm::Value *SizeVal = llvm::ConstantInt::get(IntPtr, Size);
+  
+  llvm::Value *MemCpyOps[4] = {
+    DstAddr, SrcAddr, SizeVal,llvm::ConstantInt::get(llvm::Type::Int32Ty, Align)
+  };
+  
+  Builder.CreateCall(CGM.getMemCpyFn(), MemCpyOps, 4);
 }
 
 
@@ -402,7 +434,7 @@ RValue CodeGenFunction::EmitCallExpr(const CallExpr *E) {
     if (ArgVal.isScalar())
       Args.push_back(ArgVal.getVal());
     else  // Pass by-address.  FIXME: Set attribute bit on call.
-      Args.push_back(ArgVal.getAggregateVal());
+      Args.push_back(ArgVal.getAggregateAddr());
   }
   
   llvm::Value *V = Builder.CreateCall(Callee, &Args[0], Args.size());

clang/CodeGen/CodeGenFunction.h

@@ -68,6 +68,9 @@ class RValue {
   // TODO: Encode this into the low bit of pointer for more efficient
   // return-by-value.
   bool IsAggregate;
+  
+  // FIXME: Aggregate rvalues need to retain information about whether they are
+  // volatile or not.
 public:
   
   bool isAggregate() const { return IsAggregate; }
@@ -79,8 +82,8 @@ public:
     return V;
   }
 
-  /// getAggregateVal() - Return the Value* of the address of the aggregate.
-  llvm::Value *getAggregateVal() const {
+  /// getAggregateAddr() - Return the Value* of the address of the aggregate.
+  llvm::Value *getAggregateAddr() const {
     assert(isAggregate() && "Not an aggregate!");
     return V;
   }

clang/CodeGen/CodeGenModule.cpp

@@ -15,9 +15,11 @@
 #include "CodeGenFunction.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/Decl.h"
+#include "clang/Basic/TargetInfo.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Function.h"
 #include "llvm/GlobalVariable.h"
+#include "llvm/Intrinsics.h"
 using namespace clang;
 using namespace CodeGen;
 
@@ -51,3 +53,16 @@ void CodeGenModule::EmitFunction(FunctionDecl *FD) {
   if (FD->getBody())
     CodeGenFunction(*this).GenerateCode(FD);
 }
+
+
+
+llvm::Function *CodeGenModule::getMemCpyFn() {
+  if (MemCpyFn) return MemCpyFn;
+  llvm::Intrinsic::ID IID;
+  switch (Context.Target.getPointerWidth(SourceLocation())) {
+  default: assert(0 && "Unknown ptr width");
+  case 32: IID = llvm::Intrinsic::memcpy_i32; break;
+  case 64: IID = llvm::Intrinsic::memcpy_i64; break;
+  }
+  return MemCpyFn = llvm::Intrinsic::getDeclaration(&TheModule, IID);
+}

clang/CodeGen/CodeGenModule.h

@@ -20,6 +20,7 @@
 namespace llvm {
   class Module;
   class Constant;
+  class Function;
 }
 
 namespace clang {
@@ -36,6 +37,7 @@ class CodeGenModule {
   llvm::Module &TheModule;
   CodeGenTypes Types;
 
+  llvm::Function *MemCpyFn;
   llvm::DenseMap<const Decl*, llvm::Constant*> GlobalDeclMap;
 public:
   CodeGenModule(ASTContext &C, llvm::Module &M);
@@ -46,6 +48,8 @@ public:
   
   llvm::Constant *GetAddrOfGlobalDecl(const Decl *D);
   
+  llvm::Function *getMemCpyFn();
+  
   void EmitFunction(FunctionDecl *FD);
   
   void PrintStats() {}