Sanjay Patel 3e05b40fd0 Refactor reciprocal square root estimate into target-independent function; NFC. ... This is purely a plumbing patch. No functional changes intended. The ultimate goal is to allow targets other than PowerPC (certainly X86 and Aarch64) to turn this: z = y / sqrt(x) into: z = y * rsqrte(x) using whatever HW magic they can use. See http://llvm.org/bugs/show_bug.cgi?id=20900 . The first step is to add a target hook for RSQRTE, take the already target-independent code selfishly hoarded by PPC, and put it into DAGCombiner. Next steps: The code in DAGCombiner::BuildRSQRTE() should be refactored further; tests that exercise that logic need to be added. Logic in PPCTargetLowering::BuildRSQRTE() should be hoisted into DAGCombiner. X86 and AArch64 overrides for TargetLowering.BuildRSQRTE() should be added. Differential Revision: http://reviews.llvm.org/D5425 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218219 91177308-0d34-0410-b5e6-96231b3b80d8		2014-09-21 15:19:15 +00:00
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llvm	Refactor reciprocal square root estimate into target-independent function; NFC.	2014-09-21 15:19:15 +00:00
llvm-c	[C API] Make the 'lower switch' pass available via the C API.	2014-09-11 21:32:32 +00:00