Avoids generating a legalization assert for the case where a vector type is legal but when legalizing the operation, we split the vector type and generate a library call whose type needs to be promoted. For example, X86 with SSE on but MMX off,  a divide v2i64 will be scalarized to 2 calls to a library using i64.
Avoids generating a legalization assert for the case where a vector type is legal
but when legalizing the operation, we split the vector type and generate a library
call whose type needs to be promoted. For example, X86 with SSE on but MMX off, 
a divide v2i64 will be scalarized to 2 calls to a library using i64.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@63760 91177308-0d34-0410-b5e6-96231b3b80d8

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