[PATCH] [AVX-512] - Add FMA instruction with Rounding mode

[Demikhovsky, Elena]

-  Elena

-----Original Message-----
From: Adam Nemet [mailto:anemet at apple.com] 
Sent: Wednesday, January 07, 2015 03:04
To: Badouh, Asaf; Demikhovsky, Elena; anemet at apple.com
Cc: cameron.mcinally at nyu.edu; llvm-commits at cs.uiuc.edu
Subject: Re: [PATCH] [AVX-512] - Add FMA instruction with Rounding mode

REPOSITORY
  rL LLVM

================
Comment at: lib/Target/X86/X86ISelLowering.h:374
@@ -373,1 +373,3 @@
 
+      ROUNDMODE,
+
----------------
Hmm, has this been completely thought through?  I may have missed the discussion... 

Looks like you're introducing a new node that if it surrounds an FMA op it changes its rounding mode?

What happens if the two nodes get separated by some transformation?
[Demikhovsky, Elena] We surround with VSELECT to set mask for intrinsic. The idea here is the same, even less  risky. The stage is late, all transformations are behind.
We plan to use this node for all FP arithmetic and conversion intrinsics.

================
Comment at: lib/Target/X86/X86InstrAVX512.td:3541-3542
@@ +3540,4 @@
+                              X86VectorVTInfo VTI, SDPatternOperator 
+ OpNode> {  defm v213r : avx512_fma3_round_rrb<opc213, !strconcat(OpcodeStr, "213", VTI.Suffix),
+                              VTI, OpNode>, EVEX_CD8<VTI.EltSize, 
+ CD8VF>;
+
----------------
I think that the EVEX_CD8 thing can be written as VTI.CD8TupleForm.

Same later.

http://reviews.llvm.org/D6835

EMAIL PREFERENCES
  http://reviews.llvm.org/settings/panel/emailpreferences/


---------------------------------------------------------------------
Intel Israel (74) Limited

This e-mail and any attachments may contain confidential material for
the sole use of the intended recipient(s). Any review or distribution
by others is strictly prohibited. If you are not the intended
recipient, please contact the sender and delete all copies.