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Diffstat (limited to 'lib/compiler/doc/src/notes.xml')
| -rw-r--r-- | lib/compiler/doc/src/notes.xml | 232 |
1 files changed, 212 insertions, 20 deletions
diff --git a/lib/compiler/doc/src/notes.xml b/lib/compiler/doc/src/notes.xml index 84ebd2f210..daf3bd3af9 100644 --- a/lib/compiler/doc/src/notes.xml +++ b/lib/compiler/doc/src/notes.xml @@ -8,16 +8,17 @@ <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> - The contents of this file are subject to the Erlang Public License, - Version 1.1, (the "License"); you may not use this file except in - compliance with the License. You should have received a copy of the - Erlang Public License along with this software. If not, it can be - retrieved online at http://www.erlang.org/. - - Software distributed under the License is distributed on an "AS IS" - basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See - the License for the specific language governing rights and limitations - under the License. + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. </legalnotice> @@ -31,6 +32,191 @@ <p>This document describes the changes made to the Compiler application.</p> +<section><title>Compiler 6.0.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Fix <c>get_map_elements</c> register corruption</p> + <p> + Instruction <c>get_map_elements</c> might destroy target + registers when the fail-label is taken. Only seen for + patterns with two, and only two, target registers. + Specifically if we copy one register and then jump.</p> + <p> + Own Id: OTP-12967</p> + </item> + </list> + </section> + +</section> + +<section><title>Compiler 6.0</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + The compiler optimizes away building of terms that are + never actually used. As a result, the compiler in OTP 18 + may produce more warnings for terms that are built but + not used than the compiler in OTP 17.</p> + <p> + Own Id: OTP-12453</p> + </item> + <item> + <p> + Using a map could incorrectly suppress warnings for + unused variables.</p> + <p> + Own Id: OTP-12515</p> + </item> + <item> + <p> + The compiler now properly reports unknown parse + transforms. That is, <c>undef</c> exceptions coming from + the parse transform itself is reported differently from + the absence of the parse transform.</p> + <p> + Own Id: OTP-12723</p> + </item> + <item> + <p> + Allow for 'creation of sub binary delayed' optimization + if maps instructions are in a clause.</p> + <p> + Own Id: OTP-12758</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + The <c>cerl</c> and <c>cerl_trees</c> modules in the + <c>compiler</c> application are now documented.</p> + <p> + Own Id: OTP-11978</p> + </item> + <item> + <p> + The deprecated '<c>asm</c>' option has been removed.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-12100</p> + </item> + <item> + <p> + Support variables as Map keys in expressions and patterns</p> + <p>Erlang will accept any expression as keys in Map + expressions and it will accept literals or bound + variables as keys in Map patterns.</p> + <p> + Own Id: OTP-12218</p> + </item> + <item> + <p> + Infer Map type information in beam_type compiler + optimization pass.</p> + <p> + Own Id: OTP-12253</p> + </item> + <item> + <p> + Compiler optimizations have been improved.</p> + <p> + Own Id: OTP-12393</p> + </item> + <item> + <p> + Five undocumented functions in the module <c>core_lib</c> + have been deprecated and will be removed in the next + major release. The functions are: <c>get_anno/{1,2}</c>, + <c>is_literal/1</c>, <c>is_literal_list/1</c>, and + <c>literal_value</c>. Use the appropriate functions in + the <c>cerl</c> module instead.</p> + <p> + Own Id: OTP-12497</p> + </item> + <item> + <p> + Change some internal data structures to Maps in order to + speed up compilation time. Measured speed up is around + 10%-15%.</p> + <p> + Own Id: OTP-12774</p> + </item> + <item> + <p> + Fix beam_bool pass for Maps instruction get_map_elements</p> + <p> + Before beam_split the get_map_elements instruction is + still in blocks and the helper function in beam_jump did + not reflect this.</p> + <p> + Own Id: OTP-12844 Aux Id: 17 </p> + </item> + </list> + </section> + +</section> + +<section><title>Compiler 5.0.4</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Matching out a map from a record and then updating the + record could cause a 'badarg' exception at run-time. + (Thanks to Dmitry Aleksandrov for reporting this bug.)</p> + <p> + Own Id: OTP-12402</p> + </item> + <item> + <p>The compiler would crash when compiling some complex, + nonsensical guards such as:</p> + <p> ... <c>when {{X}}, -X</c>...</p> + <p> + Own Id: OTP-12410</p> + </item> + <item> + <p> + In rare circumstances, using binary pattern in the value + part of a map pattern would cause the compiler to crash.</p> + <p> + Own Id: OTP-12414</p> + </item> + <item> + <p>Case expressions where a map was wrapped in a tuple or + list such as:</p> + <p><c>case {a,Map} of</c><br/> <c>{a,#{k:=_}}=Tuple -> + Tuple</c><br/> <c>end.</c></p> + <p>would be unsafely "optimized" to either cause an + exception at run-time or would return an empty map.</p> + <p> + Own Id: OTP-12451</p> + </item> + <item> + <p>When a variable was compared to a literal map using + the '<c>==</c>' operator, the compiler would change the + operator to '<c>=:=</c>' since it is more efficient. + However, this optimization is not safe if the map literal + has numeric keys or values. The compiler will now only do + the optimization if all keys and values are + non-numeric.</p> + <p> + Own Id: OTP-12456</p> + </item> + </list> + </section> + +</section> + <section><title>Compiler 5.0.3</title> <section><title>Fixed Bugs and Malfunctions</title> @@ -272,22 +458,28 @@ <p> EEP43: New data type - Maps</p> <p> - With Maps you may for instance: <taglist> <item><c>M0 = - #{ a => 1, b => 2}, % create - associations</c></item> <item><c>M1 = M0#{ a := 10 }, % - update values</c></item> <item><c>M2 = M1#{ "hi" => - "hello"}, % add new associations</c></item> <item><c>#{ - "hi" := V1, a := V2, b := V3} = M2. % match keys with - values</c></item> </taglist></p> + With Maps you may for instance:</p> + <taglist> + <tag/> <item><c>M0 = #{ a => 1, b => 2}, % create + associations</c></item> + <tag/><item><c>M1 = M0#{ a := 10 }, % update values</c></item> + <tag/><item><c>M2 = M1#{ "hi" => + "hello"}, % add new associations</c></item> + <tag/><item><c>#{ "hi" := V1, a := V2, b := V3} = M2. + % match keys with values</c></item> + </taglist> <p> For information on how to use Maps please see Map Expressions in the <seealso marker="doc/reference_manual:expressions#map_expressions"> Reference Manual</seealso>.</p> <p> The current implementation is without the following - features: <taglist> <item>No variable keys</item> - <item>No single value access</item> <item>No map - comprehensions</item> </taglist></p> + features:</p> + <taglist> + <tag/><item>No variable keys</item> + <tag/><item>No single value access</item> + <tag/><item>No map comprehensions</item> + </taglist> <p> Note that Maps is <em>experimental</em> during OTP 17.0.</p> <p> |