[libc++][NFC] Remove a bunch of redundant ASan existence checks (#128504)

There are currently lots of `_LIBCPP_HAS_ASAN` and
`__libcpp_is_constant_evaluated()` checks which aren't needed, since it
is centrally checked inside `__debug_utils/sanitizers.h`.

Author: philnik777

libcxx/include/__vector/vector.h

@@ -716,47 +716,32 @@ class vector {
   }
 
   _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __annotate_new(size_type __current_size) const _NOEXCEPT {
-    (void)__current_size;
-#if _LIBCPP_HAS_ASAN
     __annotate_contiguous_container(data() + capacity(), data() + __current_size);
-#endif
   }
 
   _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __annotate_delete() const _NOEXCEPT {
-#if _LIBCPP_HAS_ASAN
     __annotate_contiguous_container(data() + size(), data() + capacity());
-#endif
   }
 
   _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __annotate_increase(size_type __n) const _NOEXCEPT {
-    (void)__n;
-#if _LIBCPP_HAS_ASAN
     __annotate_contiguous_container(data() + size(), data() + size() + __n);
-#endif
   }
 
   _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __annotate_shrink(size_type __old_size) const _NOEXCEPT {
-    (void)__old_size;
-#if _LIBCPP_HAS_ASAN
     __annotate_contiguous_container(data() + __old_size, data() + size());
-#endif
   }
 
   struct _ConstructTransaction {
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit _ConstructTransaction(vector& __v, size_type __n)
         : __v_(__v), __pos_(__v.__end_), __new_end_(__v.__end_ + __n) {
-#if _LIBCPP_HAS_ASAN
       __v_.__annotate_increase(__n);
-#endif
     }
 
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI ~_ConstructTransaction() {
       __v_.__end_ = __pos_;
-#if _LIBCPP_HAS_ASAN
       if (__pos_ != __new_end_) {
         __v_.__annotate_shrink(__new_end_ - __v_.__begin_);
       }
-#endif
     }
 
     vector& __v_;

libcxx/include/string

@@ -2223,7 +2223,7 @@ private:
   __annotate_contiguous_container(const void* __old_mid, const void* __new_mid) const {
     (void)__old_mid;
     (void)__new_mid;
-#  if _LIBCPP_HAS_ASAN && _LIBCPP_INSTRUMENTED_WITH_ASAN
+#  if _LIBCPP_INSTRUMENTED_WITH_ASAN
 #    if defined(__APPLE__)
     // TODO: remove after addressing issue #96099 (https://github.com/llvm/llvm-project/issues/96099)
     if (!__is_long())
@@ -2234,34 +2234,19 @@ private:
   }
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __annotate_new(size_type __current_size) const _NOEXCEPT {
-    (void)__current_size;
-#  if _LIBCPP_HAS_ASAN && _LIBCPP_INSTRUMENTED_WITH_ASAN
-    if (!__libcpp_is_constant_evaluated())
-      __annotate_contiguous_container(data() + capacity() + 1, data() + __current_size + 1);
-#  endif
+    __annotate_contiguous_container(data() + capacity() + 1, data() + __current_size + 1);
   }
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __annotate_delete() const _NOEXCEPT {
-#  if _LIBCPP_HAS_ASAN && _LIBCPP_INSTRUMENTED_WITH_ASAN
-    if (!__libcpp_is_constant_evaluated())
-      __annotate_contiguous_container(data() + size() + 1, data() + capacity() + 1);
-#  endif
+    __annotate_contiguous_container(data() + size() + 1, data() + capacity() + 1);
   }
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __annotate_increase(size_type __n) const _NOEXCEPT {
-    (void)__n;
-#  if _LIBCPP_HAS_ASAN && _LIBCPP_INSTRUMENTED_WITH_ASAN
-    if (!__libcpp_is_constant_evaluated())
-      __annotate_contiguous_container(data() + size() + 1, data() + size() + 1 + __n);
-#  endif
+    __annotate_contiguous_container(data() + size() + 1, data() + size() + 1 + __n);
   }
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __annotate_shrink(size_type __old_size) const _NOEXCEPT {
-    (void)__old_size;
-#  if _LIBCPP_HAS_ASAN && _LIBCPP_INSTRUMENTED_WITH_ASAN
-    if (!__libcpp_is_constant_evaluated())
-      __annotate_contiguous_container(data() + __old_size + 1, data() + size() + 1);
-#  endif
+    __annotate_contiguous_container(data() + __old_size + 1, data() + size() + 1);
   }
 
   // Disable ASan annotations and enable them again when going out of scope. It is assumed that the string is in a valid

libcxx/test/std/strings/basic.string/string.nonmembers/string_op+/string.string_view.pass.cpp

@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++03, c++11, c++14, c++17, c++20, c++23
+// ADDITIONAL_COMPILE_FLAGS(has-fconstexpr-steps): -fconstexpr-steps=9000000
 
 // <string>