Daniel Sanders ea28aafa83 Fix illegal DAG produced by SelectionDAG::getConstant() for v2i64 type ... Summary: When getConstant() is called for an expanded vector type, it is split into multiple scalar constants which are then combined using appropriate build_vector and bitcast operations. In addition to the usual big/little endian differences, the case where the element-order of the vector does not have the same endianness as the elements themselves is also accounted for. For example, for v4i32 on big-endian MIPS, the byte-order of the vector is <3210,7654,BA98,FEDC>. For little-endian, it is <0123,4567,89AB,CDEF>. Handling this case turns out to be a nop since getConstant() returns a splatted vector (so reversing the element order doesn't change the value) This fixes a number of cases in MIPS MSA where calling getConstant() during operation legalization introduces illegal types (e.g. to legalize v2i64 UNDEF into a v2i64 BUILD_VECTOR of illegal i64 zeros). It should also handle bigger differences between illegal and legal types such as legalizing v2i64 into v8i16. lowerMSASplatImm() in the MIPS backend no longer needs to avoid calling getConstant() so this function has been updated in the same patch. For the sake of transparency, the steps I've taken since the review are: * Added 'virtual' to isVectorEltOrderLittleEndian() as requested. This revealed that the MIPS tests were falsely passing because a polymorphic function was not actually polymorphic in the reviewed patch. * Fixed the tests that were now failing. This involved deleting the code to handle the MIPS MSA element-order (which was previously doing an byte-order swap instead of an element-order swap). This left isVectorEltOrderLittleEndian() unused and it was deleted. * Fixed build failures caused by rebasing beyond r194467-r194472. These build failures involved the bset, bneg, and bclr instructions added in these commits using lowerMSASplatImm() in a way that was no longer valid after this patch. Some of these were fixed by calling SelectionDAG::getConstant() instead, others were fixed by a new function getBuildVectorSplat() that provided the removed functionality of lowerMSASplatImm() in a more sensible way. Reviewers: bkramer Reviewed By: bkramer CC: llvm-commits Differential Revision: http://llvm-reviews.chandlerc.com/D1973 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194811 91177308-0d34-0410-b5e6-96231b3b80d8		2013-11-15 12:56:49 +00:00
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llvm	Fix illegal DAG produced by SelectionDAG::getConstant() for v2i64 type	2013-11-15 12:56:49 +00:00
llvm-c	[llvm-c] Add missing const qualifiers to LLVMCreateTargetMachine	2013-11-15 02:51:12 +00:00