Chandler Carruth fb1293fd4c [x86] Teach the target shuffle mask extraction to recognize unary forms ... of normally binary shuffle instructions like PUNPCKL and MOVLHPS. This detects cases where a single register is used for both operands making the shuffle behave in a unary way. We detect this and adjust the mask to use the unary form which allows the existing DAG combine for shuffle instructions to actually work at all. As a consequence, this uncovered a number of obvious bugs in the existing DAG combine which are fixed. It also now canonicalizes several shuffles even with the existing lowering. These typically are trying to match the shuffle to the domain of the input where before we only really modeled them with the floating point variants. All of the cases which change to an integer shuffle here have something in the integer domain, so there are no more or fewer domain crosses here AFAICT. Technically, it might be better to go from a GPR directly to the floating point domain, but detecting floating point *outputs* despite integer inputs is a lot more code and seems unlikely to be worthwhile in practice. If folks are seeing domain-crossing regressions here though, let me know and I can hack something up to fix it. Also as a consequence, a bunch of missed opportunities to form pshufb now can be formed. Notably, splats of i8s now form pshufb. Interestingly, this improves the existing splat lowering too. We go from 3 instructions to 1. Yes, we may tie up a register, but it seems very likely to be worth it, especially if splatting the 0th byte (the common case) as then we can use a zeroed register as the mask. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214625 91177308-0d34-0410-b5e6-96231b3b80d8		2014-08-02 10:27:38 +00:00
..
Analysis	Fix ScalarEvolutionExpander when creating a PHI in a block with duplicate predecessors	2014-07-31 19:13:38 +00:00
AsmParser	Use "weak alias" instead of "alias weak"	2014-07-30 22:51:54 +00:00
Bitcode	UseListOrder: Fix blockaddress use-list order	2014-08-01 22:27:19 +00:00
CodeGen	[SDAG] Refactor the code which deletes nodes in the DAG combiner to do	2014-08-02 10:02:07 +00:00
DebugInfo	DWOHolder takes ownership of the argument constructor, use std::unique_ptr.	2014-07-31 20:26:42 +00:00
ExecutionEngine	[MCJIT] Fix an overly-aggressive check in RuntimeDyldMachOARM.	2014-08-02 03:00:49 +00:00
IR	IR: Add Value::reverseUseList()	2014-08-01 23:28:49 +00:00
IRReader	Update the MemoryBuffer API to use ErrorOr.	2014-07-06 17:43:13 +00:00
LineEditor
Linker	Include <tuple> to make buildbots happy	2014-06-27 18:38:12 +00:00
LTO	Attempt at fixing the windows dll build.	2014-07-30 23:39:30 +00:00
MC	Add support for StackMap section for ELF/Linux systems	2014-08-01 18:47:09 +00:00
Object	A std::unique_ptr case I missed in the previous patch.	2014-07-31 03:36:00 +00:00
Option	Generic: add range-adapter for option parsing.	2014-07-09 13:03:37 +00:00
ProfileData	InstrProf: Allow multiple functions with the same name	2014-08-01 22:50:07 +00:00
Support	Remove some calls to std::move.	2014-08-01 14:31:55 +00:00
TableGen	Don't fail tablegen immediately after failing to set a value.	2014-07-31 01:44:00 +00:00
Target	[x86] Teach the target shuffle mask extraction to recognize unary forms	2014-08-02 10:27:38 +00:00
Transforms	[ASan] Use metadata to pass source-level information from Clang to ASan.	2014-08-02 00:35:50 +00:00
CMakeLists.txt
LLVMBuild.txt
Makefile