path: root/lib/CodeGen/CGStmt.cpp

//===--- CGStmt.cpp - Emit LLVM Code from Statements ----------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This contains code to emit Stmt nodes as LLVM code.
//
//===----------------------------------------------------------------------===//

#include "CGDebugInfo.h"
#include "CodeGenModule.h"
#include "CodeGenFunction.h"
#include "clang/AST/StmtVisitor.h"
#include "clang/Basic/TargetInfo.h"
#include "llvm/InlineAsm.h"
#include "llvm/ADT/StringExtras.h"
using namespace clang;
using namespace CodeGen;

//===----------------------------------------------------------------------===//
//                              Statement Emission
//===----------------------------------------------------------------------===//

void CodeGenFunction::EmitStmt(const Stmt *S) {
  assert(S && "Null statement?");
  
  // Generate stoppoints if we are emitting debug info.
  // Beginning of a Compound Statement (e.g. an opening '{') does not produce 
  // executable code. So do not generate a stoppoint for that.
  CGDebugInfo *DI = CGM.getDebugInfo();
  if (DI && S->getStmtClass() != Stmt::CompoundStmtClass) {
    DI->setLocation(S->getLocStart());
    DI->EmitStopPoint(CurFn, Builder);
  }

  switch (S->getStmtClass()) {
  default:
    // Must be an expression in a stmt context.  Emit the value (to get
    // side-effects) and ignore the result.
    if (const Expr *E = dyn_cast<Expr>(S)) {
      if (!hasAggregateLLVMType(E->getType()))
        EmitScalarExpr(E);
      else if (E->getType()->isAnyComplexType())
        EmitComplexExpr(E);
      else
        EmitAggExpr(E, 0, false);
    } else {
      ErrorUnsupported(S, "statement");
    }
    break;
  case Stmt::NullStmtClass: break;
  case Stmt::CompoundStmtClass: EmitCompoundStmt(cast<CompoundStmt>(*S)); break;
  case Stmt::LabelStmtClass:    EmitLabelStmt(cast<LabelStmt>(*S));       break;
  case Stmt::GotoStmtClass:     EmitGotoStmt(cast<GotoStmt>(*S));         break;
  case Stmt::IndirectGotoStmtClass:  
    EmitIndirectGotoStmt(cast<IndirectGotoStmt>(*S)); break;

  case Stmt::IfStmtClass:       EmitIfStmt(cast<IfStmt>(*S));             break;
  case Stmt::WhileStmtClass:    EmitWhileStmt(cast<WhileStmt>(*S));       break;
  case Stmt::DoStmtClass:       EmitDoStmt(cast<DoStmt>(*S));             break;
  case Stmt::ForStmtClass:      EmitForStmt(cast<ForStmt>(*S));           break;
    
  case Stmt::ReturnStmtClass:   EmitReturnStmt(cast<ReturnStmt>(*S));     break;
  case Stmt::DeclStmtClass:     EmitDeclStmt(cast<DeclStmt>(*S));         break;
      
  case Stmt::BreakStmtClass:    
    // FIXME: Implement break in @try or @catch blocks.
    if (!ObjCEHStack.empty()) {
      CGM.ErrorUnsupported(S, "continue inside an Obj-C exception block");
      return;
    }
    EmitBreakStmt();                          
    break;

  case Stmt::ContinueStmtClass: 
    // FIXME: Implement continue in @try or @catch blocks.
    if (!ObjCEHStack.empty()) {
      CGM.ErrorUnsupported(S, "continue inside an Obj-C exception block");
      return;
    }
    EmitContinueStmt();                       
    break;

  case Stmt::SwitchStmtClass:   EmitSwitchStmt(cast<SwitchStmt>(*S));     break;
  case Stmt::DefaultStmtClass:  EmitDefaultStmt(cast<DefaultStmt>(*S));   break;
  case Stmt::CaseStmtClass:     EmitCaseStmt(cast<CaseStmt>(*S));         break;
  case Stmt::AsmStmtClass:      EmitAsmStmt(cast<AsmStmt>(*S));           break;

  case Stmt::ObjCAtTryStmtClass:
    EmitObjCAtTryStmt(cast<ObjCAtTryStmt>(*S));
    break;    
  case Stmt::ObjCAtCatchStmtClass:
    assert(0 && "@catch statements should be handled by EmitObjCAtTryStmt");
    break;
  case Stmt::ObjCAtFinallyStmtClass:
    assert(0 && "@finally statements should be handled by EmitObjCAtTryStmt");
    break;
  case Stmt::ObjCAtThrowStmtClass:
    EmitObjCAtThrowStmt(cast<ObjCAtThrowStmt>(*S));
    break;
  case Stmt::ObjCAtSynchronizedStmtClass:
    ErrorUnsupported(S, "@synchronized statement");
    break;
  case Stmt::ObjCForCollectionStmtClass: 
    EmitObjCForCollectionStmt(cast<ObjCForCollectionStmt>(*S));
    break;
  }
}

/// EmitCompoundStmt - Emit a compound statement {..} node.  If GetLast is true,
/// this captures the expression result of the last sub-statement and returns it
/// (for use by the statement expression extension).
RValue CodeGenFunction::EmitCompoundStmt(const CompoundStmt &S, bool GetLast,
                                         llvm::Value *AggLoc, bool isAggVol) {
  // FIXME: handle vla's etc.
  CGDebugInfo *DI = CGM.getDebugInfo();
  if (DI) {
    DI->setLocation(S.getLBracLoc());
    DI->EmitRegionStart(CurFn, Builder);
  }

  for (CompoundStmt::const_body_iterator I =<