1 files changed, 182 insertions, 0 deletions
diff --git a/lib/CodeGen/CodeGenFunction.cpp b/lib/CodeGen/CodeGenFunction.cpp
new file mode 100644
index 0000000000..49f23f27c3
--- /dev/null
+++ b/lib/CodeGen/CodeGenFunction.cpp
@@ -0,0 +1,182 @@
+//===--- CodeGenFunction.cpp - Emit LLVM Code from ASTs for a Function ----===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This coordinates the per-function state used while generating code.
+//
+//===----------------------------------------------------------------------===//
+
+#include "CodeGenFunction.h"
+#include "CodeGenModule.h"
+#include "clang/Basic/TargetInfo.h"
+#include "clang/AST/AST.h"
+#include "llvm/CallingConv.h"
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Function.h"
+#include "llvm/Analysis/Verifier.h"
+#include "llvm/Support/CFG.h"
+using namespace clang;
+using namespace CodeGen;
+
+CodeGenFunction::CodeGenFunction(CodeGenModule &cgm) 
+  : CGM(cgm), Target(CGM.getContext().Target), SwitchInsn(NULL), 
+    CaseRangeBlock(NULL) {}
+
+ASTContext &CodeGenFunction::getContext() const {
+  return CGM.getContext();
+}
+
+
+llvm::BasicBlock *CodeGenFunction::getBasicBlockForLabel(const LabelStmt *S) {
+  llvm::BasicBlock *&BB = LabelMap[S];
+  if (BB) return BB;
+  
+  // Create, but don't insert, the new block.
+  return BB = new llvm::BasicBlock(S->getName());
+}
+
+llvm::Constant *
+CodeGenFunction::GetAddrOfStaticLocalVar(const BlockVarDecl *BVD) {
+  return cast<llvm::Constant>(LocalDeclMap[BVD]);
+}
+
+const llvm::Type *CodeGenFunction::ConvertType(QualType T) {
+  return CGM.getTypes().ConvertType(T);
+}
+
+bool CodeGenFunction::hasAggregateLLVMType(QualType T) {
+  return !T->isRealType() && !T->isPointerType() && !T->isReferenceType() &&
+         !T->isVoidType() && !T->isVectorType() && !T->isFunctionType();
+}
+
+
+void CodeGenFunction::GenerateCode(const FunctionDecl *FD) {
+  LLVMIntTy = ConvertType(getContext().IntTy);
+  LLVMPointerWidth = static_cast<unsigned>(
+    getContext().getTypeSize(getContext().getPointerType(getContext().VoidTy)));
+  
+  CurFuncDecl = FD;
+  CurFn = cast<llvm::Function>(CGM.GetAddrOfFunctionDecl(FD, true));
+  assert(CurFn->isDeclaration() && "Function already has body?");
+  
+  // TODO: Set up linkage and many other things.  Note, this is a simple 
+  // approximation of what we really want.
+  if (FD->getAttr<DLLImportAttr>())
+    CurFn->setLinkage(llvm::Function::DLLImportLinkage);
+  else if (FD->getAttr<DLLExportAttr>())
+    CurFn->setLinkage(llvm::Function::DLLExportLinkage);
+  else if (FD->getAttr<WeakAttr>() || FD->isInline())
+    CurFn->setLinkage(llvm::Function::WeakLinkage);
+  else if (FD->getStorageClass() == FunctionDecl::Static)
+    CurFn->setLinkage(llvm::Function::InternalLinkage);
+
+  if (FD->getAttr<FastCallAttr>())
+    CurFn->setCallingConv(llvm::CallingConv::Fast);
+
+  if (const VisibilityAttr *attr = FD->getAttr<VisibilityAttr>())
+    CurFn->setVisibility(attr->getVisibility());
+  // FIXME: else handle -fvisibility
+
+
+  unsigned FuncAttrs = 0;
+  if (FD->getAttr<NoThrowAttr>())
+    FuncAttrs |= llvm::ParamAttr::NoUnwind;
+  if (FD->getAttr<NoReturnAttr>())
+    FuncAttrs |= llvm::ParamAttr::NoReturn;
+  
+  if (FuncAttrs) {
+    llvm::ParamAttrsWithIndex PAWI = 
+      llvm::ParamAttrsWithIndex::get(0, FuncAttrs);
+    CurFn->setParamAttrs(llvm::PAListPtr::get(&PAWI, 1));
+  }
+
+  llvm::BasicBlock *EntryBB = new llvm::BasicBlock("entry", CurFn);
+  
+  // Create a marker to make it easy to insert allocas into the entryblock
+  // later.  Don't create this with the builder, because we don't want it
+  // folded.
+  llvm::Value *Undef = llvm::UndefValue::get(llvm::Type::Int32Ty);
+  AllocaInsertPt = new llvm::BitCastInst(Undef, llvm::Type::Int32Ty, "allocapt",
+                                         EntryBB);
+  
+  Builder.SetInsertPoint(EntryBB);
+  
+  // Emit allocs for param decls.  Give the LLVM Argument nodes names.
+  llvm::Function::arg_iterator AI = CurFn->arg_begin();
+  
+  // Name the struct return argument.
+  if (hasAggregateLLVMType(FD->getResultType())) {
+    AI->setName("agg.result");
+    ++AI;
+  }
+  
+  for (unsigned i = 0, e = FD->getNumParams(); i != e; ++i, ++AI) {
+    assert(AI != CurFn->arg_end() && "Argument mismatch!");
+    EmitParmDecl(*FD->getParamDecl(i), AI);
+  }
+  
+  // Emit the function body.
+  EmitStmt(FD->getBody());
+  
+  // Emit a return for code that falls off the end. If insert point
+  // is a dummy block with no predecessors then remove the block itself.
+  llvm::BasicBlock *BB = Builder.GetInsertBlock();
+  if (isDummyBlock(BB))
+    BB->eraseFromParent();
+  else {
+    // FIXME: if this is C++ main, this should return 0.
+    if (CurFn->getReturnType() == llvm::Type::VoidTy)
+      Builder.CreateRetVoid();
+    else
+      Builder.CreateRet(llvm::UndefValue::get(CurFn->getReturnType()));
+  }
+  assert(BreakContinueStack.empty() &&
+         "mismatched push/pop in break/continue stack!");
+  
+  // Remove the AllocaInsertPt instruction, which is just a convenience for us.
+  AllocaInsertPt->eraseFromParent();
+  AllocaInsertPt = 0;
+  
+  // Verify that the function is well formed.
+  assert(!verifyFunction(*CurFn));
+}
+
+/// isDummyBlock - Return true if BB is an empty basic block
+/// with no predecessors.
+bool CodeGenFunction::isDummyBlock(const llvm::BasicBlock *BB) {
+  if (BB->empty() && pred_begin(BB) == pred_end(BB)) 
+    return true;
+  return false;
+}
+
+/// StartBlock - Start new block named N. If insert block is a dummy block
+/// then reuse it.
+void CodeGenFunction::StartBlock(const char *N) {
+  llvm::BasicBlock *BB = Builder.GetInsertBlock();
+  if (!isDummyBlock(BB))
+    EmitBlock(new llvm::BasicBlock(N));
+  else
+    BB->setName(N);
+}
+
+/// getCGRecordLayout - Return record layout info.
+const CGRecordLayout *CodeGenFunction::getCGRecordLayout(CodeGenTypes &CGT,
+                                                         QualType Ty) {
+  const RecordType *RTy = Ty->getAsRecordType();
+  assert (RTy && "Unexpected type. RecordType expected here.");
+
+  return CGT.getCGRecordLayout(RTy->getDecl());
+}
+
+/// WarnUnsupported - Print out a warning that codegen doesn't support the
+/// specified stmt yet.
+void CodeGenFunction::WarnUnsupported(const Stmt *S, const char *Type) {
+  CGM.WarnUnsupported(S, Type);
+}
+