Dan Gohman e3d920699c Re-enable elimination of unnecessary SUBREG_TO_REG instructions in ... LowerSubregs, and fix an x86-64 isel bug that this exposed. SUBREG_TO_REG for x86-64 implicit zero extension is only safe for isel to generate when the source is known to always have zeros in the high 32 bits. The EXTRACT_SUBREG instruction does not clear the high 32 bits. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54444 91177308-0d34-0410-b5e6-96231b3b80d8		2008-08-07 02:54:50 +00:00
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Alpha
ARM	This check is unnecessary, and getting rid of it removes a use of -disable-correct-folding.	2008-08-05 17:52:54 +00:00
CBackend
CellSPU
CPP
Generic	Fix SDISel lowering of zeroinitializer and undef to use ComputeValueVTs.	2008-08-04 23:30:41 +00:00
IA64
PowerPC
SPARC
X86	Re-enable elimination of unnecessary SUBREG_TO_REG instructions in	2008-08-07 02:54:50 +00:00