From 017460ab6c6550395e17763bd62d449586f79ab9 Mon Sep 17 00:00:00 2001
From: Mike Stump <mrs@apple.com>
Date: Thu, 1 Oct 2009 22:29:41 +0000
Subject: [PATCH] Implement a FIXME.  This improves codegen just a tad.

llvm-svn: 83221
---
 clang/lib/CodeGen/CGBlocks.cpp    | 21 +++++++++++----------
 clang/lib/CodeGen/CGDebugInfo.cpp |  4 ++--
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/clang/lib/CodeGen/CGBlocks.cpp b/clang/lib/CodeGen/CGBlocks.cpp
index ba14fea36e05..79950e8c6beb 100644
--- a/clang/lib/CodeGen/CGBlocks.cpp
+++ b/clang/lib/CodeGen/CGBlocks.cpp
@@ -663,20 +663,23 @@ CodeGenFunction::GenerateBlockFunction(const BlockExpr *BExpr,
   StartFunction(BD, ResultType, Fn, Args,
                 BExpr->getBody()->getLocEnd());
 
-  // Save a spot to insert the debug information for all the BlockDeclRefDecls.
-  llvm::BasicBlock *entry = Builder.GetInsertBlock();
-
   CurFuncDecl = OuterFuncDecl;
   CurCodeDecl = BD;
-  // FIXME: Can we straighten this out not using multiple basic blocks?
-  // Set body aside for now.
-  llvm::BasicBlock *body = createBasicBlock("body");
-  Builder.SetInsertPoint(body);
+
+  // Save a spot to insert the debug information for all the BlockDeclRefDecls.
+  llvm::BasicBlock *entry = Builder.GetInsertBlock();
+  llvm::BasicBlock::iterator entry_ptr = Builder.GetInsertPoint();
+  --entry_ptr;
+
   EmitStmt(BExpr->getBody());
+
   // Remember where we were...
   llvm::BasicBlock *resume = Builder.GetInsertBlock();
+
   // Go back to the entry.
-  Builder.SetInsertPoint(entry);
+  ++entry_ptr;
+  Builder.SetInsertPoint(entry, entry_ptr);
+
   if (CGDebugInfo *DI = getDebugInfo()) {
     // Emit debug information for all the BlockDeclRefDecls.
     for (unsigned i=0; i < BlockDeclRefDecls.size(); ++i) {
@@ -691,8 +694,6 @@ CodeGenFunction::GenerateBlockFunction(const BlockExpr *BExpr,
       }
     }
   }
-  // And now go back to the body
-  EmitBlock(body);
   // And resume where we left off.
   if (resume == 0)
     Builder.ClearInsertionPoint();
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 645125667c9a..0b386841f19d 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -1088,7 +1088,7 @@ void CGDebugInfo::EmitDeclare(const BlockDeclRefExpr *BDRE, unsigned Tag,
   // The llvm optimizer and code generator are not yet ready to support
   // optimized code debugging.
   const CompileOptions &CO = M->getCompileOpts();
-  if (CO.OptimizationLevel)
+  if (CO.OptimizationLevel || Builder.GetInsertBlock() == 0)
     return;
 
   uint64_t XOffset = 0;
@@ -1269,7 +1269,7 @@ void CGDebugInfo::EmitDeclare(const BlockDeclRefExpr *BDRE, unsigned Tag,
                                        Decl->getNameAsString(), Unit, Line, Ty,
                                        addr);
   // Insert an llvm.dbg.declare into the current block.
-  DebugFactory.InsertDeclare(Storage, D, Builder.GetInsertBlock());
+  DebugFactory.InsertDeclare(Storage, D, Builder.GetInsertPoint());
 }
 
 void CGDebugInfo::EmitDeclareOfAutoVariable(const VarDecl *Decl,