зеркало из https://github.com/mozilla/gecko-dev.git
142 строки
3.7 KiB
C++
142 строки
3.7 KiB
C++
// Test01.cpp
|
|
|
|
#include "nsIDOMNode.h"
|
|
#include "nsCOMPtr.h"
|
|
#include "nsIPtr.h"
|
|
|
|
|
|
|
|
NS_DEF_PTR(nsIDOMNode);
|
|
|
|
/*
|
|
This test file compares the generated code size of similar functions between raw
|
|
COM interface pointers (|AddRef|ing and |Release|ing by hand), |nsCOMPtr|s, and
|
|
the smart-pointer macro defined in "nsIPtr.h".
|
|
|
|
Function size results were determined by examining dissassembly of the generated code.
|
|
mXXX is the size of the generated code on the Macintosh. wXXX is the size on Windows.
|
|
For these tests, all reasonable optimizations were enabled and exceptions were
|
|
disabled (just as we build for release).
|
|
|
|
The tests in this file explore only the simplest functionality: assigning a pointer
|
|
to be reference counted into a [raw, nsCOMPtr, nsIPtr] object; ensuring that it is
|
|
|AddRef|ed and |Release|d appropriately; calling through the pointer to a function
|
|
supplied by the underlying COM interface.
|
|
|
|
Windows:
|
|
raw_optimized 31 bytes
|
|
raw, nsCOMPtr* 34
|
|
nsCOMPtr_optimized* 38
|
|
nsCOMPtr_optimized 42
|
|
nsCOMPtr 46
|
|
nsIPtr, nsIPtr_optimized 34 + 196
|
|
|
|
|
|
Macintosh:
|
|
raw_optimized, nsCOMPtr_optimized 112 bytes (1.0000)
|
|
nsCOMPtr 120 (1.0714) i.e., 7.14% bigger than raw_optimized et al
|
|
nsIPtr_optimized 124 (1.1071)
|
|
nsIPtr 136 (1.2143)
|
|
raw 140 (1.2500)
|
|
|
|
The overall difference in size between Windows and Macintosh is caused by the
|
|
the PowerPC RISC architecture where every instruction is 4 bytes.
|
|
|
|
Also note that on Windows, nsIPtr generates a out-of-line destructors
|
|
which _are_ used, totalling an additional 196 bytes of code space per class used,
|
|
per file it is used in.
|
|
|
|
On Macintosh, both nsCOMPtr and nsIPtr generate out-of-line destructors which are
|
|
not referenced, and which can be stripped by the linker.
|
|
*/
|
|
|
|
void
|
|
Test01_raw( nsIDOMNode* aDOMNode, nsString* aResult )
|
|
// m140, w34
|
|
{
|
|
/*
|
|
This test is designed to be more like a typical large function where,
|
|
because you are working with several resources, you don't just return when
|
|
one of them is |NULL|. Similarly: |Test01_nsCOMPtr00|, and |Test01_nsIPtr00|.
|
|
*/
|
|
|
|
nsIDOMNode* node = aDOMNode;
|
|
NS_IF_ADDREF(node);
|
|
|
|
if ( node )
|
|
node->GetNodeName(*aResult);
|
|
|
|
NS_IF_RELEASE(node);
|
|
}
|
|
|
|
void
|
|
Test01_raw_optimized( nsIDOMNode* aDOMNode, nsString* aResult )
|
|
// m112, w31
|
|
{
|
|
/*
|
|
This test simulates smaller functions where you _do_ just return
|
|
|NULL| at the first sign of trouble. Similarly: |Test01_nsCOMPtr01|,
|
|
and |Test01_nsIPtr01|.
|
|
*/
|
|
|
|
/*
|
|
This test produces smaller code that |Test01_raw| because it avoids
|
|
the three tests: |NS_IF_...|, and |if ( node )|.
|
|
*/
|
|
|
|
// -- the following code is assumed, but is commented out so we compare only
|
|
// the relevent generated code
|
|
|
|
// if ( !aDOMNode )
|
|
// return;
|
|
|
|
nsIDOMNode* node = aDOMNode;
|
|
NS_ADDREF(node);
|
|
node->GetNodeName(*aResult);
|
|
NS_RELEASE(node);
|
|
}
|
|
|
|
void
|
|
Test01_nsCOMPtr( nsIDOMNode* aDOMNode, nsString* aResult )
|
|
// m120, w46/34
|
|
{
|
|
nsCOMPtr<nsIDOMNode> node = aDOMNode;
|
|
|
|
if ( node )
|
|
node->GetNodeName(*aResult);
|
|
}
|
|
|
|
void
|
|
Test01_nsCOMPtr_optimized( nsIDOMNode* aDOMNode, nsString* aResult )
|
|
// m112, w42/38
|
|
{
|
|
// if ( !aDOMNode )
|
|
// return;
|
|
|
|
nsCOMPtr<nsIDOMNode> node = aDOMNode;
|
|
node->GetNodeName(*aResult);
|
|
}
|
|
|
|
void
|
|
Test01_nsIPtr( nsIDOMNode* aDOMNode, nsString* aResult )
|
|
// m136, w34
|
|
{
|
|
nsIDOMNodePtr node = aDOMNode;
|
|
node.AddRef();
|
|
|
|
if ( node.IsNotNull() )
|
|
node->GetNodeName(*aResult);
|
|
}
|
|
|
|
void
|
|
Test01_nsIPtr_optimized( nsIDOMNode* aDOMNode, nsString* aResult )
|
|
// m124, w34
|
|
{
|
|
// if ( !aDOMNode )
|
|
// return;
|
|
|
|
nsIDOMNodePtr node = aDOMNode;
|
|
node.AddRef();
|
|
node->GetNodeName(*aResult);
|
|
}
|