Nicolai Haehnle 3557fd1bae [SelectionDAG] Add expansion and promotion of [US]MUL_LOHI ... Summary: Most targets set the action for these nodes to Expand even though there isn't actually any code for them in ExpandNode. Instead, targets simply relied on the fact that no code generates these nodes as long as the nodes aren't legal or custom. However, generating these nodes can be useful e.g. for divide-by-constant in wider integer types. Expand of [US]MUL_LOHI will use MULH[US] when legal or custom, and a sequence of half-width multiplications otherwise. Promote uses a wider multiply. This patch intends to not change the generated code, but indirect effects are possible since expansions/promotions that were previously done in DAGCombine may now be done in LegalizeDAG. See D24822 for a change that actually uses the new expansion. Reviewers: spatel, bkramer, venkatra, efriedma, hfinkel, ast, nadav, tstellarAMD Subscribers: arsenm, jyknight, nemanjai, wdng, nhaehnle, llvm-commits Differential Revision: https://reviews.llvm.org/D24956 llvm-svn: 289050		2016-12-08 14:08:14 +00:00
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llvm	[SelectionDAG] Add expansion and promotion of [US]MUL_LOHI	2016-12-08 14:08:14 +00:00
llvm-c	Kill deprecated attribute API	2016-11-06 07:48:46 +00:00