Instructions

Call this from anywhere to get the function call stack and see where the current function you are in was called from

Mage::helper('stack/callstack')->toFirePhp();  
Mage::helper('stack/callstack')->toLog(); 

Example output

.../app/code/community/Timbroder/Stack/Helper/Callstack.php line 16 calls get_callstack()
.../app/design/frontend/mongoose/default/template/catalog/cms/bikes_bmx.phtml line 12 calls toLog()
.../app/design/frontend/mongoose/default/template/catalog/cms/bikes.phtml line 21 calls require_once()
.../app/code/core/Mage/Core/Block/Template.php line 212 calls include()
.../app/code/core/Mage/Core/Block/Template.php line 239 calls fetchView()
.../app/code/core/Mage/Core/Block/Template.php line 253 calls renderView()
.../app/code/core/Mage/Core/Block/Abstract.php line 668 calls _toHtml()
.../app/code/core/Mage/Core/Model/Email/Template/Filter.php line 190 calls toHtml()
.../lib/Varien/Filter/Template.php line 134 calls call_user_func()
.../app/code/core/Mage/Core/Model/Email/Template/Filter.php line 501 calls filter()
.../app/code/core/Mage/Cms/Block/Page.php line 100 calls filter()
.../app/code/core/Mage/Core/Block/Abstract.php line 668 calls _toHtml()
.../app/code/core/Mage/Core/Block/Abstract.php line 513 calls toHtml()
.../app/code/core/Mage/Core/Block/Abstract.php line 460 calls _getChildHtml()
.../app/code/local/Mage/Page/Block/Html/Wrapper.php line 52 calls getChildHtml()
.../app/code/core/Mage/Core/Block/Abstract.php line 668 calls _toHtml()
.../app/code/core/Mage/Core/Block/Text/List.php line 43 calls toHtml()
.../app/code/core/Mage/Core/Block/Abstract.php line 668 calls _toHtml()
.../app/code/core/Mage/Core/Block/Abstract.php line 513 calls toHtml()
.../app/code/core/Mage/Core/Block/Abstract.php line 464 calls _getChildHtml()
.../app/design/frontend/mongoose/default/template/page/1column.phtml line 55 calls getChildHtml()
.../app/code/core/Mage/Core/Block/Template.php line 212 calls include()
.../app/code/core/Mage/Core/Block/Template.php line 239 calls fetchView()
.../app/code/core/Mage/Core/Block/Template.php line 253 calls renderView()
.../app/code/core/Mage/Core/Block/Abstract.php line 668 calls _toHtml()
.../app/code/core/Mage/Core/Model/Layout.php line 529 calls toHtml()
.../app/code/local/Mage/Core/Controller/Varien/Action.php line 389 calls getOutput()
.../app/code/core/Mage/Cms/Helper/Page.php line 130 calls renderLayout()
.../app/code/core/Mage/Cms/Helper/Page.php line 52 calls _renderPage()
.../app/code/core/Mage/Cms/controllers/PageController.php line 45 calls renderPage()
.../app/code/local/Mage/Core/Controller/Varien/Action.php line 418 calls viewAction()
.../app/code/core/Mage/Core/Controller/Varien/Router/Standard.php line 254 calls dispatch()
.../app/code/core/Mage/Core/Controller/Varien/Front.php line 177 calls match()
.../app/code/core/Mage/Core/Model/App.php line 304 calls dispatch()
.../app/Mage.php line 598 calls run()
.../index.php line 155 calls run()