Partially merging r221686:

Only the testcase minus the MIPS-II and MIPS-IV cases have been merged.
They are required to cleanly apply a subsequent patch.
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r221686 | vkalintiris | 2014-11-11 11:43:55 +0000 (Tue, 11 Nov 2014) | 16 lines

[mips] Add preliminary support for the MIPS II target.

Summary:
This patch enables code generation for the MIPS II target. Pre-Mips32
targets don't have the MUL instruction, so we add the correspondent
pattern that uses the MULT/MFLO combination in order to retrieve the
product.

This is WIP as we don't support code generation for select nodes due to
the lack of conditional-move instructions.

Reviewers: dsanders

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D6150
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llvm-svn: 231468