Chandler Carruth 25b7d54e7f [x86,SDAG] Sink the logic for folding shuffles of splats more ... aggressively from the x86 shuffle lowering to the generic SDAG vector shuffle formation code. This code already tried to fold away shuffles of splats! It just had lots of bugs and couldn't handle the case my new x86 shuffle lowering needed. First, it failed to correctly compute whether N2 was undef because it pre-computed this, then did transformations which could *make* N2 undef, then failed to ever re-consider the precomputed state. Second, it didn't look through bitcasts at all, even in the safe cases where they are just element-type bitcasts with no change to the number of elements. Third, it didn't handle all-zero bit casts nicely the way my code in the x86 side of things did, which is essential to getting good zext-shuffle lowerings. But all of these are generic. I just ported the code down to this layer and fixed the surrounding bugs. Tests exercising this in the x86 backend still pass and some silly code in widen_cast-6.ll gets better. I updated that test to be a bit more precise but it's still pretty unclear what the value of the test is in this day and age. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212517 91177308-0d34-0410-b5e6-96231b3b80d8		2014-07-08 08:45:38 +00:00
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AArch64	Allow AArch64FastISel to degrade graceully in the presence of an MVT::i128	2014-07-07 21:37:51 +00:00
ARM	ARM: properly lower dllimport'ed global values	2014-07-07 05:18:35 +00:00
CPP
Generic
Hexagon
Inputs
Mips	[mips] Add tests for the 'ret', 'call', and 'indirectbr' LLVM IR instruction.	2014-07-04 15:16:14 +00:00
MSP430
NVPTX
PowerPC	[PowerPC] Fix testcase regression	2014-07-07 19:41:54 +00:00
R600	R600: Fix mishandling of load / store chains.	2014-07-07 18:34:45 +00:00
SPARC
SystemZ
Thumb
Thumb2
X86	[x86,SDAG] Sink the logic for folding shuffles of splats more	2014-07-08 08:45:38 +00:00
XCore	llvm/test/CodeGen/XCore/dwarf_debug.ll: Fix not to be affected by *-win32.	2014-07-04 11:58:03 +00:00