Artyom Skrobov 190815e2ea Adding support for TargetLoweringBase::LibCall ... Summary: TargetLoweringBase::Expand is defined as "Try to expand this to other ops, otherwise use a libcall." For ISD::UDIV and ISD::SDIV, the choice between the two possibilities was defined in a rather convoluted way: - if DIVREM is legal, expand to DIVREM - if DIVREM has a custom lowering, expand to DIVREM - if DIVREM libcall is defined and a remainder from the same division is computed elsewhere, expand to a DIVREM libcall - else, expand to a DIV libcall This had the undesirable effect that if both DIV and DIVREM are implemented as libcalls, then ISD::UDIV and ISD::SDIV are expanded to the heavier DIVREM libcall, even when the remainder isn't used. The new code adds a new LegalizeAction, TargetLoweringBase::LibCall, so that backends can directly control whether they prefer an expansion or a conversion to a libcall. This makes the generic lowering code even more generic, allowing its reuse in a wider range of target-specific configurations. The useful effect is that ARM backend will now generate a call to __aeabi_{i,u}div rather than __aeabi_{i,u}divmod in cases where it doesn't need the remainder. There's no functional change outside the ARM backend. Reviewers: t.p.northover, rengolin Subscribers: t.p.northover, llvm-commits, aemerson Differential Revision: http://reviews.llvm.org/D13862 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250826 91177308-0d34-0410-b5e6-96231b3b80d8		2015-10-20 13:14:52 +00:00
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llvm	Adding support for TargetLoweringBase::LibCall	2015-10-20 13:14:52 +00:00
llvm-c	[WinEH] Add cleanupendpad instruction	2015-09-03 09:09:43 +00:00