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<chapter>
  <header>
    <copyright>
      <year>2006</year><year>2010</year>
      <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.

    </legalnotice>

    <title>HiPE Release Notes</title>
    <prepared>otp_appnotes</prepared>
    <docno>nil</docno>
    <date>nil</date>
    <rev>nil</rev>
    <file>notes.xml</file>
  </header>
  <p>This document describes the changes made to HiPE.</p>

<section><title>Hipe 3.7.9</title>

    <section><title>Fixed Bugs and Malfunctions</title>
      <list>
        <item>
          <p>
	    Fix erroneous fail info of a hipe_bs_primop</p>
          <p>
	    Own Id: OTP-9036</p>
        </item>
        <item>
          <p>
	    The change fixes a bug in the translation of 'bs_add'
	    BEAM instruction to HiPE's Icode representation. When
	    these instructions appeared in a guard context the
	    previous translation was obviously buggy.</p>
          <p>
	    Own Id: OTP-9044</p>
        </item>
        <item>
          <p>
	    Sanitize the specs of the code module</p>
          <p>
	    After the addition of unicode_binary() to the
	    file:filename() type, dialyzer started complaining about
	    erroneous or incomplete specs in some functions of the
	    'code' module. The culprit was hard-coded information in
	    erl_bif_types for functions of this module, which were
	    not updated. Since these functions have proper specs
	    these days and code duplication (pun intended) is never a
	    good idea, their type information was removed from
	    erl_bif_types.</p>
          <p>
	    While doing this, some erroneous comments were fixed in
	    the code module and also made sure that the code now runs
	    without dialyzer warnings even when the
	    -Wunmatched_returns option is used.</p>
          <p>
	    Some cleanups were applied to erl_bif_types too.</p>
          <p>
	    Own Id: OTP-9100</p>
        </item>
        <item>
          <p>
	    Fix bug in the simplification of inexact comparisons</p>
          <p>
	    On 31/1/2011 Paul Guyot reported a bug in the native code
	    compilation of inexact equality/inequality tests between
	    floats and integers. The relevant test was:</p>
          <p>
	    f(X) -&gt; Y = X / 2, Y == 0.</p>
          <p>
	    and hipe erroneously evaluated the calls f(0) and f(0.0)
	    to 'false'.</p>
          <p>
	    The culprit was in the simplification code of the Icode
	    range analysis which used an erroneous test (lists:any/1
	    instead of lists:all/1).</p>
          <p>
	    Own Id: OTP-9101</p>
        </item>
        <item>
          <p>
	    Document exiting and garbage_collecting process statuses</p>
          <p>
	    Own Id: OTP-9102</p>
        </item>
        <item>
          <p>
	    Remove hipe constants pool</p>
          <p>
	    Hipe constants used to be allocated within a single,
	    fixed-size pool for interaction with the garbage
	    collector. However, the garbage collector no longer
	    depends on constants being allocated within a single
	    pool, and the fixed size of the pool both meant
	    unnecessary allocations on most deployments and crashes
	    on deployments requiring more constants.</p>
          <p>
	    The code was simplified to directly invoke erts_alloc.
	    Debugging and undocumented function
	    hipe_bifs:show_literals/0 was removed (it returned true
	    and output text to the console), and debugging and
	    undocumented function hipe_bifs:constants_size/0 was
	    rewritten with a global to count the size of allocated
	    constants.</p>
          <p>
	    Own Id: OTP-9128</p>
        </item>
      </list>
    </section>

</section>

<section><title>Hipe 3.7.8.1</title>

    <section><title>Fixed Bugs and Malfunctions</title>
      <list>
        <item>
          <p>
	    Several type specifications for standard libraries were
	    wrong in the R14B01 release. This is now corrected. The
	    corrections concern types in re,io,filename and the
	    module erlang itself.</p>
          <p>
	    Own Id: OTP-9008</p>
        </item>
      </list>
    </section>

</section>

<section><title>Hipe 3.7.8</title>

    <section><title>Improvements and New Features</title>
      <list>
        <item>
          <p>
	    Compiler warnings were eliminated.</p>
          <p>
	    Own Id: OTP-8855</p>
        </item>
      </list>
    </section>

</section>

<section><title>Hipe 3.7.7</title>

    <section><title>Fixed Bugs and Malfunctions</title>
      <list>
        <item>
	    <p>The HiPE compiler could crash when compiling certain
	    modules (the bug has been latent, and been exposed by new
	    optimizations introduced in the BEAM compiler in R14A).
	    (Thanks to Mikael Pettersson.)</p>
          <p>
	    Own Id: OTP-8800</p>
        </item>
        <item>
          <p>
	    hipe:load/1 was broken. (Thanks to Paul Guyot.)</p>
          <p>
	    Own Id: OTP-8802</p>
        </item>
      </list>
    </section>

</section>

<section><title>Hipe 3.7.6</title>

    <section><title>Improvements and New Features</title>
      <list>
        <item>
	    <p><c>receive</c> statements that can only read out a
	    newly created reference are now specially optimized so
	    that it will execute in constant time regardless of the
	    number of messages in the receive queue for the process.
	    That optimization will benefit calls to
	    <c>gen_server:call()</c>. (See <c>gen:do_call/4</c> for
	    an example of a receive statement that will be
	    optimized.)</p>
          <p>
	    Own Id: OTP-8623</p>
        </item>
        <item>
          <p>
	    Various changes to dialyzer-related files for R14.</p>
          <p>
	    - Dialyzer properly supports the new attribute
	    -export_type and checks that remote types only refer to
	    exported types. A warning is produced if some
	    files/applications refer to types defined in modules
	    which are neither in the PLT nor in the analyzed
	    applications.</p>
          <p>
	    - Support for detecting data races involving whereis/1
	    and unregister/1.</p>
          <p>
	    - More precise identification of the reason(s) why a
	    record construction violates the types declared for its
	    fields.</p>
          <p>
	    - Fixed bug in the handling of the 'or' guard.</p>
          <p>
	    - Better handling of the erlang:element/2 BIF.</p>
          <p>
	    - Complete handling of Erlang BIFs.</p>
          <p>
	    Own Id: OTP-8699</p>
        </item>
        <item>
	    <p><c>eprof</c> has been reimplemented with support in
	    the Erlang virtual machine and is now both faster (i.e.
	    slows down the code being measured less) and scales much
	    better. In measurements we saw speed-ups compared to the
	    old eprof ranging from 6 times (for sequential code that
	    only uses one scheduler/core) up to 84 times (for
	    parallel code that uses 8 cores).</p>
	    <p>Note: The API for the <c>eprof</c> has been cleaned up
	    and extended. See the documentation.</p>
          <p>
	    *** POTENTIAL INCOMPATIBILITY ***</p>
          <p>
	    Own Id: OTP-8706</p>
        </item>
      </list>
    </section>

</section>

<section><title>Hipe 3.7.5</title>

    <section><title>Improvements and New Features</title>
      <list>
        <item>
	    <p>The documentation is now possible to build in an open
	    source environment after a number of bugs are fixed and
	    some features are added in the documentation build
	    process. </p>
	    <p>- The arity calculation is updated.</p>
	    <p>- The module prefix used in the function names for
	    bif's are removed in the generated links so the links
	    will look like
	    "http://www.erlang.org/doc/man/erlang.html#append_element-2"
	    instead of
	    "http://www.erlang.org/doc/man/erlang.html#erlang:append_element-2".</p>
	    <p>- Enhanced the menu positioning in the html
	    documentation when a new page is loaded.</p>
	    <p>- A number of corrections in the generation of man
	    pages (thanks to Sergei Golovan)</p>
	    <p>- The legal notice is taken from the xml book file so
	    OTP's build process can be used for non OTP
	    applications.</p>
          <p>
	    Own Id: OTP-8343</p>
        </item>
      </list>
    </section>

</section>

<section><title>Hipe 3.7.4</title>

    <section><title>Improvements and New Features</title>
      <list>
        <item>
          <p>
	    The documentation is now built with open source tools
	    (xsltproc and fop) that exists on most platforms. One
	    visible change is that the frames are removed.</p>
          <p>
	    Own Id: OTP-8201</p>
        </item>
        <item>
          <p>
	    Misc updates.</p>
          <p>
	    Own Id: OTP-8301</p>
        </item>
      </list>
    </section>

</section>

<section><title>Hipe 3.7.3</title>

    <section><title>Improvements and New Features</title>
      <list>
        <item>
          <p>
	    Various small bugs (one involving the handling of large
	    binaries) were corrected and some additions to its
	    functionality and/or code cleanups were done.</p>
          <p>
	    Own Id: OTP-8189</p>
        </item>
      </list>
    </section>

</section>

<section><title>Hipe 3.7.2</title>

    <section><title>Improvements and New Features</title>
      <list>
        <item>
          <p>
	    Miscellanous updates.</p>
          <p>
	    Own Id: OTP-8038</p>
        </item>
      </list>
    </section>

</section>

<section><title>Hipe 3.7.1</title>

    <section><title>Improvements and New Features</title>
      <list>
        <item>
          <p>
	    Minor updates and bug fixes.</p>
          <p>
	    Own Id: OTP-7958</p>
        </item>
      </list>
    </section>

</section>


<section><title>Hipe 3.7</title>

    <section><title>Improvements and New Features</title>
      <list>
        <item>
          <p>
	    Miscellaneous updates.</p>
          <p>
	    Own Id: OTP-7877</p>
        </item>
      </list>
    </section>

</section>

<section><title>Hipe 3.6.9</title>

    <section><title>Improvements and New Features</title>
      <list>
        <item>
	    <p>The <c>--disable-hipe</c> option for the
	    <c>configure</c> will now completely disable the hipe
	    run-time in the emulator, as is the expected
	    behaviour.</p>
          <p>
	    Own Id: OTP-7631</p>
        </item>
      </list>
    </section>

</section>

<section><title>Hipe 3.6.8</title>

    <section><title>Improvements and New Features</title>
      <list>
        <item>
          <p>
	    Minor updates.</p>
          <p>
	    Own Id: OTP-7522</p>
        </item>
      </list>
    </section>

</section>


<section><title>Hipe 3.6.7</title>

    <section><title>Improvements and New Features</title>
      <list>
        <item>
          <p>
	    Minor changes.</p>
          <p>
	    Own Id: OTP-7388</p>
        </item>
      </list>
    </section>

</section>

<section><title>Hipe 3.6.6</title>

    <section><title>Fixed Bugs and Malfunctions</title>
      <list>
        <item>
	    <p>A fix for an #include problem which caused the FP
	    exception test to fail unnecessarily on
	    debian/glibc-2.7/x86 systems.</p>
	    <p>Added SIGFPE loop detection to the FP exception test.
	    This prevents the test from looping indefinitely, which
	    could happen when the CPU is supported (so we can enable
	    FP exceptions on it) but the OS isn't (so we can't write
	    a proper SIGFPE handler). x86 on an unsupported OS is
	    known to have had this problem.</p>
          <p>
	    Own Id: OTP-7254</p>
        </item>
      </list>
    </section>


    <section><title>Improvements and New Features</title>
      <list>
        <item>
          <p>
	    HiPE now also supports little-endian ARM processors.</p>
          <p>
	    Own Id: OTP-7255</p>
        </item>
      </list>
    </section>

</section>

<section><title>Hipe 3.6.5</title>

    <section><title>Fixed Bugs and Malfunctions</title>
      <list>
        <item>
          <p>
	    HIPE: Corrected the choice of interface to the send/3 and
	    setnode/3 BIFs for native-compiled code. Using the
	    incorrect interface could, in unusual circumstances, lead
	    to random runtime errors.</p>
          <p>
	    Own Id: OTP-7067</p>
        </item>
      </list>
    </section>


    <section><title>Improvements and New Features</title>
      <list>
        <item>
          <p>
	    The HiPE compiler's SPARC backend has been rewritten,
	    improving its correctness and long-term maintainability.</p>
          <p>
	    Own Id: OTP-7133</p>
        </item>
      </list>
    </section>

</section>

  <section>
    <title>Hipe 3.6.3</title>

    <section>
      <title>Improvements and New Features</title>
      <list type="bulleted">
        <item>
          <p>Minor Makefile changes.</p>
          <p>Own Id: OTP-6689</p>
        </item>
        <item>
          <p>Miscellanous updates.</p>
          <p>Own Id: OTP-6738</p>
        </item>
      </list>
    </section>
  </section>

  <section>
    <title>Hipe 3.6.2</title>

    <section>
      <title>Improvements and New Features</title>
      <list type="bulleted">
        <item>
          <p>Miscellanous improvements.</p>
          <p>Own Id: OTP-6577</p>
        </item>
      </list>
    </section>
  </section>

  <section>
    <title>Hipe 3.6.1.1</title>

    <section>
      <title>Fixed Bugs and Malfunctions</title>
      <list type="bulleted">
        <item>
          <p>Dialyzer could fail to analyze certain beam files that
            used try/catch.</p>
          <p>Own Id: OTP-6449 Aux Id: seq10563 </p>
        </item>
      </list>
    </section>
  </section>

  <section>
    <title>Hipe 3.6.1</title>

    <section>
      <title>Improvements and New Features</title>
      <list type="bulleted">
        <item>
          <p>HiPE runtime system:</p>
          <p>* added notes about supported systems to README</p>
          <p>* support 32-bit x86 on FreeBSD</p>
          <p>* autoenable HiPE on FreeBSD (32-bit x86) and Solaris
            (64-bit x86)</p>
          <p>* updated x86 runtime system to support glibc-2.5</p>
          <p>* work around probable gcc-4.1.1 bug affecting the x86
            runtime system</p>
          <p>HiPE compiler:</p>
          <p>* improved performance of integer multiplications on
            all platforms</p>
          <p>* corrected a code optimisation error in R11B-2 that
            broke some bsl/bsr operations on all platforms</p>
          <p>* corrected a type error in the ARM backend which
            could cause the compiler to crash</p>
          <p>* corrected an error in the SPARC backend's naive
            register allocator which could throw the compiler into an
            infinite loop</p>
          <p>Own Id: OTP-6423</p>
        </item>
      </list>
    </section>
  </section>

  <section>
    <title>Hipe 3.6.0</title>

    <section>
      <title>Improvements and New Features</title>
      <list type="bulleted">
        <item>
          <p>Support for native code on Solaris 10/AMD64.</p>
          <p>Support for native code on FreeBSD/AMD64.</p>
          <p>Native code now handles external funs (<c><![CDATA[fun M:F/A]]></c>). Native code can now also apply so-called
            tuple-funs (<c><![CDATA[{M,F}]]></c>). (Tuple funs are NOT
            recommended for new code; they are deprecated and will be
            removed in some future release.)</p>
          <p>Own Id: OTP-6305</p>
        </item>
      </list>
    </section>
  </section>

  <section>
    <title>Hipe 3.5.6</title>

    <section>
      <title>Improvements and New Features</title>
      <list type="bulleted">
        <item>
          <p>Improved compilation of receives for the SMP runtime
            system.</p>
          <p>Improved code quality in HiPE compiler on ARM.</p>
          <p>Fix bug in handling of re-raised exceptions in
            try-catch.</p>
          <p>(HiPE loader) When native code is incompatible with
            the current runtime system, fall back to loading the BEAM
            code.</p>
          <p>Own Id: OTP-6127</p>
        </item>
      </list>
    </section>
  </section>
</chapter>

