[libc++] Refactor vector constructors to eliminate code duplication

[winner245]

This PR refactors the std::vector's initializer_list constructors to reduce code duplication.
The constructors now call __init_with_size directly, reducing code duplication and improving
readability and maintainability.

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[llvmbot]

@llvm/pr-subscribers-libcxx

Author: None (winner245)

Changes

This PR refactors the std::vector's initializer_list constructors vector(initializer_list<value_type> __il, const allocator_type& __a) and vector(initializer_list<value_type> __il) to reduce code duplication. The constructors now call __init_with_size directly, reducing code duplication and improving readability and maintainability.

---

Full diff: https://github.com/llvm/llvm-project/pull/113193.diff

1 Files Affected:

• (modified) libcxx/include/vector (+2-12)

diff --git a/libcxx/include/vector b/libcxx/include/vector
index dc31f31838264c..5ee2ca52752e23 100644
--- a/libcxx/include/vector
+++ b/libcxx/include/vector
@@ -1292,24 +1292,14 @@ vector<_Tp, _Allocator>::vector(vector&& __x, const __type_identity_t<allocator_
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI
 vector<_Tp, _Allocator>::vector(initializer_list<value_type> __il) {
-  auto __guard = std::__make_exception_guard(__destroy_vector(*this));
-  if (__il.size() > 0) {
-    __vallocate(__il.size());
-    __construct_at_end(__il.begin(), __il.end(), __il.size());
-  }
-  __guard.__complete();
+  __init_with_size(__il.begin(), __il.end(), __il.size());
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20 inline _LIBCPP_HIDE_FROM_ABI
 vector<_Tp, _Allocator>::vector(initializer_list<value_type> __il, const allocator_type& __a)
     : __alloc_(__a) {
-  auto __guard = std::__make_exception_guard(__destroy_vector(*this));
-  if (__il.size() > 0) {
-    __vallocate(__il.size());
-    __construct_at_end(__il.begin(), __il.end(), __il.size());
-  }
-  __guard.__complete();
+  __init_with_size(__il.begin(), __il.end(), __il.size());;
 }
 
 #endif // _LIBCPP_CXX03_LANG

[ldionne]

LGTM with green CI. The code previously in vector(initializer_list) was an exact duplicate of __init_with_size().

[github-actions]

✅ With the latest revision this PR passed the C/C++ code formatter.

[winner245]

Hi team,

It looks like the checks were cancelled due to my recent push to fix clang-format issues. I apologize for the inconvenience. This is my very first contribution to the LLVM project. Could someone please help me to re-trigger the checks? I appreciate all your help.

Thanks in advance,
Peng

[ldionne]

@winner245 LLVM has a requirement that each commit is associated to a valid e-mail address. Can you please uncheck the "hide my email" option from your Github preferences?

[winner245]

Hi @ldionne and team,

I have unckecked "hide my email" in my settings. Please let me know if there is anything else from my side. I would also like to take this opportunity to express my sincere gratitude for all your invaluable guidance and help throughout this entire process. Though it’s a small step, it truly means a lot to me. I’m eager to continue contributing on this great journey and look forward to learning more from you in the future.

Thank you so much for your help!

Best regards,
Peng

[ldionne]

Thanks for your contribution!

[github-actions]

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