Simon Tatham 92a8f6251f [ARM,MVE] Add intrinsics and isel for MVE fused multiply-add. ... Summary: This adds the ACLE intrinsic family for the VFMA and VFMS instructions, which perform fused multiply-add on vectors of floats. I've represented the unpredicated versions in IR using the cross- platform `@llvm.fma` IR intrinsic. We already had isel rules to convert one of those into a vector VFMA in the simplest possible way; but we didn't have rules to detect a negated argument and turn it into VFMS, or rules to detect a splat argument and turn it into one of the two vector/scalar forms of the instruction. Now we have all of those. The predicated form uses a target-specific intrinsic as usual, but I've stuck to just one, for a predicated FMA. The subtraction and splat versions are code-generated by passing an fneg or a splat as one of its operands, the same way as the unpredicated version. In arm_mve_defs.h, I've had to introduce a tiny extra piece of infrastructure: a record `id` for use in codegen dags which implements the identity function. (Just because you can't declare a Tablegen value of type dag which is //only// a `$varname`: you have to wrap it in something. Now I can write `(id $varname)` to get the same effect.) Reviewers: dmgreen, MarkMurrayARM, miyuki, ostannard Reviewed By: dmgreen Subscribers: kristof.beyls, hiraditya, danielkiss, cfe-commits, llvm-commits Tags: #clang, #llvm Differential Revision: https://reviews.llvm.org/D75998		2020-03-12 11:13:50 +00:00
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llvm	[ARM,MVE] Add intrinsics and isel for MVE fused multiply-add.	2020-03-12 11:13:50 +00:00
llvm-c	Add debug info support for Swift/Clang APINotes.	2020-03-11 18:47:30 -07:00