6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-07-23 01:30:19 +00:00
Code Issues Projects Releases Wiki Activity
LLVM backend for 6502
106,934 Commits 39 Branches 0 Tags 277 MiB
C++ 48.7%
LLVM 38.5%
Assembly 10.2%
C 0.9%
Python 0.4%
Other 1.2%
89cea3c36b
Go to file
Andrea Di Biagio 89cea3c36b [DAGCombiner] Improve the folding of target independet shuffles to Undef. 
When combining a pair of shuffle nodes, check if the combined shuffle mask is
trivially Undef. In case, immediately fold that pair of shuffles to Undef.

The lack of checks for undef masks was the root-cause of a poor-codegen bug
in the dag combiner.

Example:
  %1 = shufflevector <4 x i32> %A, <4 x i32> %B, <4 x i32> <i32 4, i32 1, i32 1, i32 6>
  %2 = shufflevector <4 x i32> %1, <4 x i32> undef, <4 x i32> <i32 0, i32 4, i32 1, i32 6>
  %3 = shufflevector <4 x i32> %2, <4 x i32> undef, <4 x i32> <i32 1, i32 5, i32 3, i32 3>

Before this patch, on x86 (with -mcpu=corei7) we failed to fold the entire
sequence to Undef value and therefore we generated:
  shufps $-123, %xmm1, $xmm0
  pshufd $-46, %xmm0, %xmm0

With this patch, the entire shuffle sequence is folded to Undef and no
shuffles are generated in the output assembly.

Added new test cases to test 'combine-vec-shuffle-5.ll'.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215797 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-16 00:29:44 +00:00
autoconf Delete support for AuroraUX. 2014-08-14 15:15:09 +00:00
bindings [OCaml] Expose Llvm.get_operand_use. 2014-08-12 02:55:45 +00:00
cmake Make message about building sphinx documentation with CMake more 2014-08-14 11:57:16 +00:00
docs [LIT]Correct name of global lit configuration object to be lit_config (not lit). 2014-08-15 05:54:19 +00:00
examples Temporarily Revert "Nuke the old JIT." as it's not quite ready to 2014-08-07 22:02:54 +00:00
include Make isAliased property for fixed-offset stack objects adjustable 2014-08-16 00:17:02 +00:00
lib [DAGCombiner] Improve the folding of target independet shuffles to Undef. 2014-08-16 00:29:44 +00:00
projects [cmake] Use the external project machinery for libcxxabi so that it can 2014-07-25 10:27:40 +00:00
test [DAGCombiner] Improve the folding of target independet shuffles to Undef. 2014-08-16 00:29:44 +00:00
tools Silencing some -Wcast-qual warnings and removing some C-style casts at the same time. NFC. 2014-08-14 13:53:19 +00:00
unittests Revert "[Support] Promote cl::StringSaver to a separate utility" 2014-08-15 23:39:01 +00:00
utils Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
.arcconfig Updated phabricator server. 2014-04-07 03:57:04 +00:00
.clang-format
.gitignore Add Polly to the ignored trees. 2014-06-25 13:13:36 +00:00
CMakeLists.txt Fix building with in-tree libc++abi on FreeBSD 2014-08-01 19:23:15 +00:00
CODE_OWNERS.TXT Add a sentence that all entries should include an email address. 2014-08-04 19:33:25 +00:00
configure Delete support for AuroraUX. 2014-08-14 15:15:09 +00:00
CREDITS.TXT Test commit access 2014-08-09 16:05:23 +00:00
LICENSE.TXT
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 Delete support for AuroraUX. 2014-08-14 15:15:09 +00:00
README.txt Trivial test commit. 2014-04-26 19:05:45 +00:00

README.txt 

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.