Doc: Describe Compiler Explorer

Fixes: QTCREATORBUG-29720
Change-Id: I1de27d01a684249cd8bd3e5e8c98a551947a4436
Reviewed-by: Marcus Tillmanns <marcus.tillmanns@qt.io>

dist/changelog/changes-12.0.0.md

@@ -36,6 +36,8 @@ Every language, compiler and library that is supported at https://godbolt.org
 is also supported in Qt Creator. You can save your Compiler Explorer session as
 a `.qtce` file (JSON-based).
 
+([Documentation](https://doc-snapshots.qt.io/qtcreator-12.0/creator-how-to-explore-compiler-code.html))
+
 ### CMake Debugging and the Debug Adapter Protocol
 
 Set breakpoints in a CMake file and select `DAP` and `CMake Preset` in `Debug`

doc/qtcreator/src/howto/creator-only/creator-how-tos.qdoc

@@ -58,6 +58,7 @@
             \li \l {Add libraries to projects}
             \li \l {Add subprojects to projects}
             \li \l {Add wizards}
+            \li \l {Create compiler explorer sessions}
             \li \l {Create C++ classes}
             \li \l {Create files}
             \li \l {Create OpenGL fragment and vertex shaders}
@@ -79,6 +80,10 @@
 
     \section1 Build and Run
 
+    \list
+        \li \l {Explore compiler code}
+    \endlist
+
     \section2 Manage Kits
 
         \list

doc/qtcreator/src/projects/creator-only/creator-files-creating.qdoc

@@ -46,6 +46,10 @@
             or list models, \QD forms and a matching classes for Qt Widgets
             projects, Qt resource files, as well as QML and JavaScript files
             for Qt Quick projects.
+    \row
+        \li \uicontrol {Compiler Explorer}
+        \li Example setup for using Compiler Explorer to compile C++ or Python
+            code.
     \row
         \li \uicontrol {GLSL}
         \li OpenGL fragment and vertex shaders.
@@ -68,8 +72,9 @@
         \li Empty Nim source and script files.
     \endtable
 
-    \sa {Create C++ classes}, {Create OpenGL fragment and vertex shaders},
-    {Create resource files}, {Use project wizards}
+    \sa {Create compiler explorer sessions}, {Create C++ classes},
+    {Create OpenGL fragment and vertex shaders}, {Create resource files},
+    {Use project wizards}
 */
 
 /*!

doc/qtcreator/src/projects/creator-only/creator-how-to-create-compiler-explorer-setup.qdoc

@@ -0,0 +1,95 @@
+// Copyright (C) 2023 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
+
+/*!
+    \page creator-how-to-create-compiler-explorer-sessions.html
+    \previouspage creator-how-tos.html
+
+    \ingroup creator-how-to-projects
+
+    \title Create compiler explorer sessions
+
+    To create a compiler explorer session for a C++ or Python project:
+
+    \list 1
+        \li Select \uicontrol File > \uicontrol {New File} >
+            \uicontrol {Compiler Explorer} > \uicontrol C++ or \uicontrol Python
+            > \uicontrol Choose.
+        \li Follow the instructions of the wizard to create an example
+            compiler explorer session as a JSON-based \c .qtce file and to open
+            it.
+    \endlist
+
+    \note Enable the Compiler Explorer plugin to use it.
+
+    \sa {Create files}, {Enable and disable plugins}, {Explore compiler code}
+*/
+
+/*!
+    \page creator-how-to-explore-compiler-code.html
+    \previouspage creator-how-tos.html
+
+    \ingroup creator-how-to-build
+
+    \title Explore compiler code
+
+    With the \l{https://godbolt.org/}{Compiler Explorer}, you can enter code to
+    explore the capabilities of your compilers and interpreters. \QC supports
+    all languages, compilers, and libraries that Compiler Explorer supports. You
+    can save your compiler explorer session as a JSON-based \c .qtce file.
+
+    \image qtcreator-compiler-explorer.webp {Python code in the compiler explorer}
+
+    \note Enable the Compiler Explorer plugin to use it.
+
+    To check how a compiler sees C++ or Python code:
+
+    \list 1
+        \li Select \uicontrol Tools > \uicontrol {Compiler Explorer} >
+            \uicontrol {Open Compiler Explorer}.
+        \li In the \uicontrol Language field, select the language to compile.
+        \li In the \uicontrol Compiler field, select a compiler to see the
+            assembly code.
+        \li Enter code to see the resulting assembly code.
+    \endlist
+
+    You can also see the application status and output.
+
+    To explore several compilers, select \uicontrol {Add Compiler}.
+
+    \section1 Set compiler options
+
+    Select \inlineimage icons/settings.png
+    to set compiler options.
+
+    \table
+    \header
+        \li Setting
+        \li Value
+    \row
+        \li Compiler options
+        \li Arguments passed to the compiler. Add options to enable optimization
+            and to change other aspects of the compilation.
+    \row
+        \li Libraries
+        \li Add the libraries that your code links against.
+    \row
+        \li Execute the code
+        \li Execute the resulting executable.
+    \row
+        \li Compile to binary object
+        \li Convert the source code to a binary executable.
+    \row
+        \li Intel asm syntax
+        \li Use the Intel ASM syntax for writing the assembly code.
+    \row
+        \li Demangle identifiers
+        \li Extract and demangle identifiers from mangled symbols.
+            \e {Name mangling} adds descriptive data to a function's identifier
+            at link time. The data indicates which namespace and object a
+            function belongs to and which arguments it handles in which order.
+    \endtable
+
+    \sa {Create compiler explorer sessions}, {Enable and disable plugins},
+    {Add compilers}, {Add custom compilers}
+*/

doc/qtcreator/src/qtcreator-toc.qdoc

@@ -211,6 +211,7 @@
                     \li \l {Add libraries to projects}
                     \li \l {Add subprojects to projects}
                     \li \l {Add wizards}
+                    \li \l {Create compiler explorer sessions}
                     \li \l {Create C++ classes}
                     \li \l {Create files}
                     \li \l {Create OpenGL fragment and vertex shaders}
@@ -233,6 +234,7 @@
                     \li \l {Add Nim compilers}
                     \li \l {Add Qt versions}
                     \li \l {Edit Qbs profiles}
+                    \li \l {Explore compiler code}
                 \endlist
             \li Read Qt Documentation
                 \list