Old fork of llvm-mirror, used on older RPCS3 builds
Go to file
Kevin Qin dbaeb6e7cb Use a loop to simplify the runtime unrolling prologue.
Runtime unrolling will create a prologue to execute the extra
iterations which is can't divided by the unroll factor. It
generates an if-then-else sequence to jump into a factor -1
times unrolled loop body, like

    extraiters = tripcount % loopfactor
    if (extraiters == 0) jump Loop:
    if (extraiters == loopfactor) jump L1
    if (extraiters == loopfactor-1) jump L2
    ...
    L1:  LoopBody;
    L2:  LoopBody;
    ...
    if tripcount < loopfactor jump End
    Loop:
    ...
    End:

It means if the unroll factor is 4, the loop body will be 7
times unrolled, 3 are in loop prologue, and 4 are in the loop.
This commit is to use a loop to execute the extra iterations
in prologue, like

        extraiters = tripcount % loopfactor
        if (extraiters == 0) jump Loop:
        else jump Prol
 Prol:  LoopBody;
        extraiters -= 1                 // Omitted if unroll factor is 2.
        if (extraiters != 0) jump Prol: // Omitted if unroll factor is 2.
        if (tripcount < loopfactor) jump End
 Loop:
 ...
 End:

Then when unroll factor is 4, the loop body will be copied by
only 5 times, 1 in the prologue loop, 4 in the original loop.
And if the unroll factor is 2, new loop won't be created, just
as the original solution.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218604 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-29 11:15:00 +00:00
autoconf Delete support for AuroraUX. 2014-08-14 15:15:09 +00:00
bindings Reinstate "Nuke the old JIT." 2014-09-02 22:28:02 +00:00
cmake Add LLVM_ENABLE_MODULES flag to CMake to enable building with C++ modules. 2014-09-26 22:40:15 +00:00
docs fix a typo in doumentation index. 2014-09-26 06:59:15 +00:00
examples Add doInitialization/doFinalization to DataLayoutPass. 2014-09-10 21:27:43 +00:00
include Remove dead code from DIBuilder 2014-09-29 06:32:54 +00:00
lib Use a loop to simplify the runtime unrolling prologue. 2014-09-29 11:15:00 +00:00
projects [cmake] Use the external project machinery for libcxxabi so that it can 2014-07-25 10:27:40 +00:00
test Use a loop to simplify the runtime unrolling prologue. 2014-09-29 11:15:00 +00:00
tools llvm-vtabledump: Further simplification 2014-09-26 22:32:19 +00:00
unittests [Support] Add type-safe alternative to llvm::format() 2014-09-25 20:30:58 +00:00
utils Reduce code duplication a bit. 2014-09-27 05:26:42 +00:00
.arcconfig Updated phabricator server. 2014-04-07 03:57:04 +00:00
.clang-format
.clang-tidy Add .clang-tidy configuration file to provide LLVM-optimized defaults for 2014-09-08 13:30:00 +00:00
.gitignore Add Polly to the ignored trees. 2014-06-25 13:13:36 +00:00
CMakeLists.txt Add LLVM_ENABLE_MODULES flag to CMake to enable building with C++ modules. 2014-09-26 22:40:15 +00:00
CODE_OWNERS.TXT Add Tom Stellard's role as 3.5 release manager. 2014-09-12 08:07:31 +00:00
configure Delete support for AuroraUX. 2014-08-14 15:15:09 +00:00
CREDITS.TXT Rise from the dead and update personal info 2014-08-25 17:51:04 +00:00
LICENSE.TXT Remove projects/sample. 2014-03-12 22:40:22 +00:00
llvm.spec.in
LLVMBuild.txt
Makefile [configure/make] Propagate names of build host tools when making BuildTools 2014-03-25 21:45:41 +00:00
Makefile.common
Makefile.config.in Track clang r213171 2014-07-16 16:50:34 +00:00
Makefile.rules Revert my earlier change to add "all" as a dependency to check. In 2014-09-19 18:44:27 +00:00
README.txt Trivial test commit. 2014-04-26 19:05:45 +00:00

Low Level Virtual Machine (LLVM)
================================

This directory and its subdirectories contain source code for the Low Level
Virtual Machine, a toolkit for the construction of highly optimized compilers,
optimizers, and runtime environments.

LLVM is open source software. You may freely distribute it under the terms of
the license agreement found in LICENSE.txt.

Please see the documentation provided in docs/ for further
assistance with LLVM, and in particular docs/GettingStarted.rst for getting
started with LLVM and docs/README.txt for an overview of LLVM's
documentation setup.

If you're writing a package for LLVM, see docs/Packaging.rst for our
suggestions.