2 Commits

Author	SHA1	Message	Date
Tim Northover	fef8e383eb	ARM64: use 32-bit moves for constants where possible. ... If we know that a particular 64-bit constant has all high bits zero, then we can rely on the fact that 32-bit ARM64 instructions automatically zero out the high bits of an x-register. This gives the expansion logic less constraints to satisfy and so sometimes allows it to pick better sequences. Came up while porting test/CodeGen/AArch64/movw-consts.ll: this will allow a 32-bit MOVN to be used in @test8 soon. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206379 91177308-0d34-0410-b5e6-96231b3b80d8	2014-04-16 11:52:51 +00:00
Tim Northover	7b837d8c75	ARM64: initial backend import ... This adds a second implementation of the AArch64 architecture to LLVM, accessible in parallel via the "arm64" triple. The plan over the coming weeks & months is to merge the two into a single backend, during which time thorough code review should naturally occur. Everything will be easier with the target in-tree though, hence this commit. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205090 91177308-0d34-0410-b5e6-96231b3b80d8	2014-03-29 10:18:08 +00:00