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
..
Analysis	Add @llvm.assume, lowering, and some basic properties	2014-07-25 21:13:35 +00:00
Assembler	verify-uselistorder: Change the default -num-shuffles=5	2014-07-31 18:46:24 +00:00
Bindings	[OCaml] Add Llvm.{string_of_const,const_element}.	2014-08-03 23:54:22 +00:00
Bitcode	Don't upgrade global constructors when reading bitcode	2014-08-12 16:46:37 +00:00
BugPoint	llvm/test/BugPoint/compile-custom.ll: Use explicit %python to invoke a test script, compile-custom.ll.py, for shebang-incapable hosts.	2014-07-11 14:44:10 +00:00
CodeGen	[DAGCombiner] Improve the folding of target independet shuffles to Undef.	2014-08-16 00:29:44 +00:00
DebugInfo	Revert several FastISel commits to track down a buildbot error.	2014-08-14 19:56:28 +00:00
ExecutionEngine	Add missing Interpreter intrinsic lowering for sin, cos and ceil	2014-08-08 15:00:12 +00:00
Feature	Use "weak alias" instead of "alias weak"	2014-07-30 22:51:54 +00:00
FileCheck	FileCheck: Add a flag to allow checking empty input	2014-08-07 18:40:37 +00:00
Instrumentation	Revert r215415 which causse MSan to crash on a great deal of C++ code.	2014-08-13 09:19:39 +00:00
Integer
JitListener
Linker	Set comdats when lazily linking functions.	2014-08-15 20:17:08 +00:00
LTO
MC	Remove HasLEB128.	2014-08-15 14:01:07 +00:00
Object	pr20589: Fix duplicated arch flag.	2014-08-08 16:18:29 +00:00
Other	Don't internalize all but main by default.	2014-08-05 20:10:38 +00:00
TableGen	llvm/test/TableGen/*Foreach*.td: Remove XFAIL:vg_leak. They have not been failing since r215176.	2014-08-12 14:06:21 +00:00
tools	Make the test a bit more strict.	2014-08-12 15:55:27 +00:00
Transforms	Copy noalias metadata from call sites to inlined instructions	2014-08-14 21:09:37 +00:00
Unit	Let test/Unit/lit.cfg add config.shlibdir to $PATH on DLL platforms like cygming.	2014-07-04 05:11:55 +00:00
Verifier	Use "weak alias" instead of "alias weak"	2014-07-30 22:51:54 +00:00
YAMLParser
.clang-format
CMakeLists.txt	Rename llvm-uselistorder => verify-uselistorder	2014-07-30 17:11:27 +00:00
lit.cfg	Temporarily Revert "Nuke the old JIT." as it's not quite ready to	2014-08-07 22:02:54 +00:00
lit.site.cfg.in	Add missing Interpreter intrinsic lowering for sin, cos and ceil	2014-08-08 15:00:12 +00:00
Makefile	Delete support for AuroraUX.	2014-08-14 15:15:09 +00:00
Makefile.tests
TestRunner.sh