Optimize appends in CFX_XMLNode::InsertChildNode().
Skip to the end of the linked list instead of traversing it.
BUG=chromium:895234
Change-Id: I56d6bee3cd099a1a7343eb2b067d522ec69c261a
Reviewed-on: https://pdfium-review.googlesource.com/c/44172
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
diff --git a/core/fxcrt/xml/cfx_xmlnode.cpp b/core/fxcrt/xml/cfx_xmlnode.cpp
index 59eb3f7..4fbc8bc 100644
--- a/core/fxcrt/xml/cfx_xmlnode.cpp
+++ b/core/fxcrt/xml/cfx_xmlnode.cpp
@@ -58,12 +58,18 @@
return;
}
- int32_t iCount = 0;
- CFX_XMLNode* pFind = first_child_;
+ CFX_XMLNode* pFind;
// Note, negative indexes, and indexes after the end of the list will result
// in appending to the list.
- while (++iCount != index && pFind->next_sibling_)
- pFind = pFind->next_sibling_;
+ if (index < 0) {
+ // Optimize the negative index case.
+ pFind = last_child_;
+ } else {
+ pFind = first_child_;
+ int32_t iCount = 0;
+ while (++iCount != index && pFind->next_sibling_)
+ pFind = pFind->next_sibling_;
+ }
pNode->prev_sibling_ = pFind;
if (pFind->next_sibling_)
