[llvm-commits] llvm-gcc: Codegen VIEW_CONVERT_EXPR into bitcast where possible.

[Chris Lattner]

I applied this:

===================================================================
--- llvm-convert.cpp    (revision 121164)
+++ llvm-convert.cpp    (working copy)
@@ -2209,18 +2209,26 @@
      return 0;
    }
-  // Otherwise, this is a scalar to scalar conversion.  FIXME: this  
should use
-  // a bitcast or int_to_ptr/ptr_to_int when cast changes land.  For  
now, go
-  // through memory. :P
+  // Otherwise, this is a scalar to scalar conversion.
    Value *OpVal = Emit(Op, 0);
    assert(OpVal && "Expected a scalar result!");
+  const Type *DestTy = ConvertType(TREE_TYPE(exp));
+
+  // If the source is a pointer, use ptrtoint to get it to something
+  // bitcast'able.  This supports things like v_c_e(foo*, float).
+  if (isa<PointerType>(OpVal->getType())) {
+    if (isa<PointerType>(DestTy))   // ptr->ptr is a simple bitcast.
+      return new BitCastInst(OpVal, DestTy, "tmp", CurBB);
+    // Otherwise, ptrtoint to intptr_t first.
+    OpVal = new PtrToIntInst(OpVal, TD.getIntPtrType(), "tmp", CurBB);
+  }
+
+  // If the destination type is a pointer, use inttoptr.
+  if (isa<PointerType>(DestTy))
+    return new IntToPtrInst(OpVal, DestTy, "tmp", CurBB);
-  Value *TmpLoc = CreateTemporary(OpVal->getType());
-  new StoreInst(OpVal, TmpLoc, CurBB);
-
-  // Cast the memory to the right type.
-  TmpLoc = CastToType(TmpLoc, PointerType::get(ConvertType(TREE_TYPE 
(exp))));
-  return new LoadInst(TmpLoc, "tmp", CurBB);
+  // Otherwise, use a bitcast.
+  return new BitCastInst(OpVal, DestTy, "tmp", CurBB);
}
Value *TreeToLLVM::EmitNEGATE_EXPR(tree exp, Value *DestLoc) {

-Chris