Chandler Carruth a341a8070a [x86] Fix two independent miscompiles in the process of getting the same ... test case to actually generate correct code. The primary miscompile fixed here is that we weren't correctly handling in-place elements in one half of a single-input v8i16 shuffle when moving a dword of elements from that half to the other half. Some times, we would clobber the in-place elements in forming the dword to move across halves. The fix to this involves forcibly marking the in-place inputs even when there is no need to gather them into a dword, and to much more carefully re-arrange the elements when grouping them into a dword to move across halves. With these two changes we would generate correct shuffles for the test case, but found another miscompile. There are also some random perturbations of the generated shuffle pattern in SSE2. It looks like a wash; more instructions in some cases fewer in others. The second miscompile would corrupt the results into nonsense. This is a buggy pattern in one of the added DAG combines. Mapping elements through a PSHUFD when pairing redundant half-shuffles is *much* harder than this code makes it out to be -- it requires reasoning about *all* of where the input is used in the PSHUFD, not just one part of where it is used. Plus, we can't combine a half shuffle *into* a PSHUFD but the code didn't guard against it. I think this was just a bad idea and I've just removed that aspect of the combine. No tests regress as a consequence so seems OK. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214954 91177308-0d34-0410-b5e6-96231b3b80d8		2014-08-06 10:16:36 +00:00
..
Analysis	Teach the SLP Vectorizer that keeping some values live over a callsite can have a cost.	2014-08-05 12:30:34 +00:00
AsmParser	Remove dead code in condition	2014-08-05 18:22:58 +00:00
Bitcode	BitcodeReader: Fix non-determinism in use-list order	2014-08-05 17:49:48 +00:00
CodeGen	DebugInfo: Assert that any CU for which debug_loc lists are emitted, has at least one range.	2014-08-06 00:21:25 +00:00
DebugInfo	DWOHolder takes ownership of the argument constructor, use std::unique_ptr.	2014-07-31 20:26:42 +00:00
ExecutionEngine	Remove the TargetMachine forwards for TargetSubtargetInfo based	2014-08-04 21:25:23 +00:00
IR	Provide convenient access to the zext/sext attributes of function arguments. NFC.	2014-08-05 05:43:41 +00:00
IRReader
LineEditor
Linker
LTO	Don't internalize all but main by default.	2014-08-05 20:10:38 +00:00
MC	Enable Darwin vararg parameters support in assembler macros.	2014-08-04 23:14:37 +00:00
Object	A std::unique_ptr case I missed in the previous patch.	2014-07-31 03:36:00 +00:00
Option
ProfileData	Coverage: add HasCodeBefore flag to a mapping region.	2014-08-04 18:00:51 +00:00
Support	Path: Stop claiming path::const_iterator is bidirectional	2014-08-04 17:36:41 +00:00
TableGen	Allow binary and for tblgen math.	2014-08-05 09:43:25 +00:00
Target	[x86] Fix two independent miscompiles in the process of getting the same	2014-08-06 10:16:36 +00:00
Transforms	[dfsan] Try not to create too many additional basic blocks in functions which	2014-08-06 00:33:40 +00:00
CMakeLists.txt
LLVMBuild.txt
Makefile