1=========================
2LLVM 12.0.0 Release Notes
3=========================
4
5.. contents::
6    :local:
7
8.. warning::
9   These are in-progress notes for the upcoming LLVM 12 release.
10   Release notes for previous releases can be found on
11   `the Download Page <https://releases.llvm.org/download.html>`_.
12
13
14Introduction
15============
16
17This document contains the release notes for the LLVM Compiler Infrastructure,
18release 12.0.0.  Here we describe the status of LLVM, including major improvements
19from the previous release, improvements in various subprojects of LLVM, and
20some of the current users of the code.  All LLVM releases may be downloaded
21from the `LLVM releases web site <https://llvm.org/releases/>`_.
22
23For more information about LLVM, including information about the latest
24release, please check out the `main LLVM web site <https://llvm.org/>`_.  If you
25have questions or comments, the `LLVM Developer's Mailing List
26<https://lists.llvm.org/mailman/listinfo/llvm-dev>`_ is a good place to send
27them.
28
29Note that if you are reading this file from a Git checkout or the main
30LLVM web page, this document applies to the *next* release, not the current
31one.  To see the release notes for a specific release, please see the `releases
32page <https://llvm.org/releases/>`_.
33
34Non-comprehensive list of changes in this release
35=================================================
36.. NOTE
37   For small 1-3 sentence descriptions, just add an entry at the end of
38   this list. If your description won't fit comfortably in one bullet
39   point (e.g. maybe you would like to give an example of the
40   functionality, or simply have a lot to talk about), see the `NOTE` below
41   for adding a new subsection.
42
43* ...
44
45
46.. NOTE
47   If you would like to document a larger change, then you can add a
48   subsection about it right here. You can copy the following boilerplate
49   and un-indent it (the indentation causes it to be inside this comment).
50
51   Special New Feature
52   -------------------
53
54   Makes programs 10x faster by doing Special New Thing.
55
56
57Changes to the LLVM IR
58----------------------
59
60* ...
61
62* Added the ``byref`` attribute to better represent argument passing
63  for the `amdgpu_kernel` calling convention.
64
65Changes to building LLVM
66------------------------
67
68Changes to TableGen
69-------------------
70
71* The syntax for specifying an integer range in a range list has changed.
72  The old syntax used a hyphen in the range (e.g., ``{0-9}``). The new syntax
73  uses the "`...`" range punctuator (e.g., ``{0...9}``). The hyphen syntax
74  is deprecated. The "TableGen Language Reference" document has been updated.
75
76Changes to the ARM Backend
77--------------------------
78
79During this release ...
80
81Changes to the MIPS Target
82--------------------------
83
84During this release ...
85
86
87Changes to the PowerPC Target
88-----------------------------
89
90During this release ...
91
92Changes to the X86 Target
93-------------------------
94
95During this release ...
96
97* The 'mpx' feature was removed from the backend. It had been removed from clang
98  frontend in 10.0. Mention of the 'mpx' feature in an IR file will print a
99  message to stderr, but IR should still compile.
100
101Changes to the AMDGPU Target
102-----------------------------
103
104During this release ...
105
106* The new ``byref`` attribute is now the preferred method for
107  representing aggregate kernel arguments.
108
109Changes to the AVR Target
110-----------------------------
111
112During this release ...
113
114Changes to the WebAssembly Target
115---------------------------------
116
117During this release ...
118
119Changes to the OCaml bindings
120-----------------------------
121
122
123
124Changes to the C API
125--------------------
126
127
128Changes to the Go bindings
129--------------------------
130
131
132Changes to the DAG infrastructure
133---------------------------------
134
135
136Changes to the Debug Info
137---------------------------------
138
139During this release ...
140
141Changes to the LLVM tools
142---------------------------------
143
144* llvm-readobj and llvm-readelf behavior has changed to report an error when
145  executed with no input files instead of reading an input from stdin.
146  Reading from stdin can still be achieved by specifying `-` as an input file.
147
148Changes to LLDB
149---------------------------------
150
151External Open Source Projects Using LLVM 12
152===========================================
153
154* A project...
155
156
157Additional Information
158======================
159
160A wide variety of additional information is available on the `LLVM web page
161<https://llvm.org/>`_, in particular in the `documentation
162<https://llvm.org/docs/>`_ section.  The web page also contains versions of the
163API documentation which is up-to-date with the Git version of the source
164code.  You can access versions of these documents specific to this release by
165going into the ``llvm/docs/`` directory in the LLVM tree.
166
167If you have any questions or comments about LLVM, please feel free to contact
168us via the `mailing lists <https://llvm.org/docs/#mailing-lists>`_.
169