Note: this list is generated by pattern matching, so it may include some functions that are not actually implementations of this hook.

admin_bar_preprocess_page in core/modules/admin_bar/admin_bar.module
Implements hook_preprocess_page().
bartik_preprocess_layout in core/themes/bartik/template.php
Prepares variables for layout template files.
bartik_preprocess_maintenance_page in core/themes/bartik/template.php
Prepares variables for maintenance page templates.
basis_preprocess_header in core/themes/basis/template.php
Prepares variables for header templates.
basis_preprocess_layout in core/themes/basis/template.php
Prepares variables for layout templates.
basis_preprocess_maintenance_page in core/themes/basis/template.php
Prepares variables for maintenance page templates.
basis_preprocess_node in core/themes/basis/template.php
Prepares variables for node templates.
basis_preprocess_page in core/themes/basis/template.php
Prepares variables for page templates.
book_preprocess_block in core/modules/book/book.module
Implements hook_preprocess_block().
comment_preprocess_block in core/modules/comment/comment.module
Implements hook_preprocess_block().
comment_preprocess_node in core/modules/comment/comment.module
Prepares variables for comment.tpl.php
dashboard_preprocess_block in core/modules/dashboard/dashboard.module
Implements hook_preprocess_block().
dashboard_preprocess_layout in core/modules/dashboard/dashboard.module
Implements hook_preprocess_layout().
date_preprocess_views_view in core/modules/date/date.theme.inc
Implements template_preprocess_views_view().
entityreference_preprocess_file_entity in core/modules/entityreference/entityreference.module
Implements hook_preprocess_file_entity().
entityreference_preprocess_node in core/modules/entityreference/entityreference.module
Implements hook_preprocess_node().
entityreference_preprocess_taxonomy_term in core/modules/entityreference/entityreference.module
Implements hook_preprocess_taxonomy_term().
image_preprocess_image_style in core/modules/image/image.module
Preprocess function for theme_image_style().
layout_preprocess_layout in core/modules/layout/layout.theme.inc
Prepares variables for layout templates.
locale_preprocess_block in core/modules/locale/locale.module
Implements hook_preprocess_block().
locale_preprocess_node in core/modules/locale/locale.module
Implements MODULE_preprocess_HOOK().
menu_preprocess_block in core/modules/menu/menu.module
Implements hook_preprocess_block().
node_row_node_view_preprocess_node in core/modules/node/views/node.views.inc
Implements hook_preprocess_node().
search_embedded_form_preprocess_search_results in core/modules/search/tests/search_embedded_form/search_embedded_form.module
Adds the test form to search results.
search_preprocess_block in core/modules/search/search.module
Implements hook_preprocess_block().
seven_preprocess_layout in core/themes/seven/template.php
Prepares variables for layout templates.
seven_preprocess_maintenance_page in core/themes/seven/template.php
seven_preprocess_page in core/themes/seven/template.php
Implements hook_preprocess_page().
system_preprocess_block in core/modules/system/system.module
Implements hook_preprocess_block().
system_preprocess_page_components in core/modules/system/system.theme.inc
Prepares variables for Page Component block templates.
template_preprocess_block in core/modules/layout/layout.theme.inc
Prepares variables for block templates.
template_preprocess_block_dynamic in core/modules/layout/layout.theme.inc
Prepares variables for block-dynamic templates.
template_preprocess_book_all_books_block in core/modules/book/book.theme.inc
Processes variables for book-all-books-block.tpl.php.
template_preprocess_book_navigation in core/modules/book/book.theme.inc
Processes variables for book-navigation.tpl.php.
template_preprocess_ckeditor5_settings_toolbar in core/modules/ckeditor5/ckeditor5.theme.inc
Preprocess variables for theme_ckeditor5_settings_toolbar().
template_preprocess_ckeditor_settings_toolbar in core/modules/ckeditor/ckeditor.theme.inc
Preprocess variables for theme_ckeditor_settings_toolbar().
template_preprocess_comment in core/modules/comment/comment.theme.inc
Preprocesses variables for comment.tpl.php.
template_preprocess_contextual_links_example_object in modules/examples/contextual_links_example/contextual_links_example.module
Process variables for contextual-links-example-object.tpl.php.
template_preprocess_datetime in core/includes/theme.inc
Preprocess variables for theme_datetime().
template_preprocess_date_views_filter_form in core/modules/date/date.theme.inc
Preprocessor for Date Views filter form.
template_preprocess_date_views_pager in core/modules/date/date.theme.inc
Preprocess function for Date pager template.
template_preprocess_entity in core/modules/entity/entity.theme.inc
Process variables for entity.tpl.php.
template_preprocess_field in core/modules/field/field.theme.inc
Theme preprocess function for theme_field() and field.tpl.php.
template_preprocess_file_entity in core/modules/file/file.module
Process variables for file.tpl.php
template_preprocess_header in core/includes/theme.inc
Preprocess variables for header.tpl.php
template_preprocess_image in core/includes/theme.inc
Preprocess variables for theme_image().
template_preprocess_installer_browser_block in core/modules/installer/installer.theme.inc
Add some variables for the project browse block theme.
template_preprocess_installer_browser_install in core/modules/installer/installer.theme.inc
Add some variables for the projects install theme.
template_preprocess_installer_browser_install_queue in core/modules/installer/installer.theme.inc
Add some variables for the projects install queue theme.
template_preprocess_installer_browser_list in core/modules/installer/installer.theme.inc
Add some variables for the projects list theme.
template_preprocess_installer_browser_project in core/modules/installer/installer.theme.inc
Add some variables for the project theme.
template_preprocess_installer_browser_project_dialog in core/modules/installer/installer.theme.inc
Add some variables for the project details dialog.
template_preprocess_layout__simmons in core/layouts/simmons/simmons.php
Process variables for the simmons layout.
template_preprocess_layout__three_three_four_column in core/layouts/legacy/three_three_four_column/three_three_four_column.php
Process variables for the 3/3/4 column layout.
template_preprocess_maintenance_page in core/includes/theme.inc
Prepares variables for maintenance-page templates.
template_preprocess_menu_tree in core/includes/menu.inc
Implements template_preprocess_HOOK() for theme_menu_tree().
template_preprocess_node in core/modules/node/node.theme.inc
Processes variables for node.tpl.php.
template_preprocess_page in core/includes/theme.inc
Preprocess variables for page.tpl.php
template_preprocess_search_results in core/modules/search/search.theme.inc
Process variables for search-results.tpl.php.
template_preprocess_taxonomy_term in core/modules/taxonomy/taxonomy.theme.inc
Process variables for taxonomy-term.tpl.php.
template_preprocess_theme_test in core/modules/simpletest/tests/theme_test.theme.inc
Preprocesses variables for theme_theme_test().
template_preprocess_theming_example_text_form in modules/examples/theming_example/theming_example.module
Implements template_preprocess().
template_preprocess_username in core/modules/user/user.theme.inc
Preprocesses variables for theme_username().
template_preprocess_user_picture in core/modules/user/user.theme.inc
Process variables for user-picture.tpl.php.
template_preprocess_user_profile in core/modules/user/user.theme.inc
Process variables for user-profile.tpl.php.
template_preprocess_views_exposed_form in core/modules/views/templates/views.theme.inc
Default theme function for all filter forms.
template_preprocess_views_ui_display_tab_bucket in core/modules/views_ui/views_ui.theme.inc
template_preprocess_views_ui_display_tab_column in core/modules/views_ui/views_ui.theme.inc
template_preprocess_views_ui_display_tab_setting in core/modules/views_ui/views_ui.theme.inc
template_preprocess_views_ui_view_preview_section in core/modules/views_ui/views_ui.theme.inc
Theme preprocess for theme_views_ui_view_preview_section().
template_preprocess_views_view in core/modules/views/templates/views.theme.inc
Preprocess the primary theme implementation for a view.
template_preprocess_views_view_field in core/modules/views/templates/views.theme.inc
Process a single field within a view.
template_preprocess_views_view_fields in core/modules/views/templates/views.theme.inc
Preprocess theme function to print a single record from a row, with fields
template_preprocess_views_view_grid in core/modules/views/templates/views.theme.inc
Display a view as a grid style.
template_preprocess_views_view_grouping in core/modules/views/templates/views.theme.inc
Process a single grouping within a view.
template_preprocess_views_view_list in core/modules/views/templates/views.theme.inc
Display the view as an HTML list element
template_preprocess_views_view_mapping_test in core/modules/views/tests/views_test/views_test.module
Implements hook_preprocess_HOOK() for theme_views_view_mapping_test().
template_preprocess_views_view_row_comment in core/modules/comment/views/comment.views.inc
Template helper for theme_views_view_row_comment
template_preprocess_views_view_row_rss in core/modules/views/templates/views.theme.inc
Default theme function for all RSS rows.
template_preprocess_views_view_row_search in core/modules/search/views/search.views.inc
Template helper for theme_views_view_row_search
template_preprocess_views_view_rss in core/modules/views/templates/views.theme.inc
Preprocess an RSS feed
template_preprocess_views_view_summary in core/modules/views/templates/views.theme.inc
Preprocess theme function to print a single record from a row, with fields
template_preprocess_views_view_summary_unformatted in core/modules/views/templates/views.theme.inc
Template preprocess theme function to print summary basically unformatted.
template_preprocess_views_view_table in core/modules/views/templates/views.theme.inc
Display a view as a table style.
template_preprocess_views_view_unformatted in core/modules/views/templates/views.theme.inc
Display the simple view of rows one after another
theme_test_preprocess_page in core/modules/simpletest/tests/theme_test.module
Implements hook_preprocess_page().
user_preprocess_block in core/modules/user/user.module
Implements hook_preprocess_block().
views_preprocess_comment in core/modules/views/views.module
A theme preprocess function to automatically allow view-based node templates if called from a view.
views_preprocess_layout in core/modules/views/views.module
Implements hook_preprocess_layout().
views_preprocess_node in core/modules/views/views.module
A theme preprocess function to automatically allow view-based node templates if called from a view.
views_ui_preprocess_views_view in core/modules/views_ui/views_ui.module
Theme preprocess for views-view.tpl.php.