[llvm] r324861 - [X86] Add KADD X86ISD opcode instead of reusing ISD::ADD.

[Craig Topper via llvm-commits]

Author: ctopper
Date: Sun Feb 11 17:33:38 2018
New Revision: 324861

URL: http://llvm.org/viewvc/llvm-project?rev=324861&view=rev
Log:
[X86] Add KADD X86ISD opcode instead of reusing ISD::ADD.

ISD::ADD implies individual vector element addition with no carries between elements. But for a vXi1 type that would be the same as XOR. And we already turn ISD::ADD into ISD::XOR for all vXi1 types during lowering. So the ISD::ADD pattern would never be able to match anyway.

KADD is different, it adds the elements but also propagates a carry between them. This just a way of doing an add in k-register without bitcasting to the scalar domain. There's still no way to match the pattern, but at least its not obviously wrong.

Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
    llvm/trunk/lib/Target/X86/X86ISelLowering.h
    llvm/trunk/lib/Target/X86/X86InstrAVX512.td
    llvm/trunk/lib/Target/X86/X86InstrFragmentsSIMD.td

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=324861&r1=324860&r2=324861&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Sun Feb 11 17:33:38 2018
@@ -25336,6 +25336,7 @@ const char *X86TargetLowering::getTarget
   case X86ISD::TESTP:              return "X86ISD::TESTP";
   case X86ISD::KORTEST:            return "X86ISD::KORTEST";
   case X86ISD::KTEST:              return "X86ISD::KTEST";
+  case X86ISD::KADD:               return "X86ISD::KADD";
   case X86ISD::KSHIFTL:            return "X86ISD::KSHIFTL";
   case X86ISD::KSHIFTR:            return "X86ISD::KSHIFTR";
   case X86ISD::PACKSS:             return "X86ISD::PACKSS";

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.h?rev=324861&r1=324860&r2=324861&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.h (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.h Sun Feb 11 17:33:38 2018
@@ -372,6 +372,9 @@ namespace llvm {
       KORTEST,
       KTEST,
 
+      // ADD for masks.
+      KADD,
+
       // Several flavors of instructions with vector shuffle behaviors.
       // Saturated signed/unnsigned packing.
       PACKSS,

Modified: llvm/trunk/lib/Target/X86/X86InstrAVX512.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86InstrAVX512.td?rev=324861&r1=324860&r2=324861&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86InstrAVX512.td (original)
+++ llvm/trunk/lib/Target/X86/X86InstrAVX512.td Sun Feb 11 17:33:38 2018
@@ -2956,7 +2956,7 @@ defm KOR   : avx512_mask_binop_all<0x45,
 defm KXNOR : avx512_mask_binop_all<0x46, "kxnor", vxnor, SSE_BIT_ITINS_P, 1>;
 defm KXOR  : avx512_mask_binop_all<0x47, "kxor",  xor,   SSE_BIT_ITINS_P, 1>;
 defm KANDN : avx512_mask_binop_all<0x42, "kandn", vandn, SSE_BIT_ITINS_P, 0>;
-defm KADD  : avx512_mask_binop_all<0x4A, "kadd",  add,   SSE_BIT_ITINS_P, 1, HasDQI>;
+defm KADD  : avx512_mask_binop_all<0x4A, "kadd",  X86kadd, SSE_BIT_ITINS_P, 1, HasDQI>;
 
 multiclass avx512_binop_pat<SDPatternOperator VOpNode, SDPatternOperator OpNode,
                             Instruction Inst> {

Modified: llvm/trunk/lib/Target/X86/X86InstrFragmentsSIMD.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86InstrFragmentsSIMD.td?rev=324861&r1=324860&r2=324861&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86InstrFragmentsSIMD.td (original)
+++ llvm/trunk/lib/Target/X86/X86InstrFragmentsSIMD.td Sun Feb 11 17:33:38 2018
@@ -205,6 +205,8 @@ def X86kshiftr : SDNode<"X86ISD::KSHIFTR
                                              SDTCisSameAs<0, 1>,
                                              SDTCisVT<2, i8>]>>;
 
+def X86kadd : SDNode<"X86ISD::KADD", SDTIntBinOp, [SDNPCommutative]>;
+
 def X86vrotli  : SDNode<"X86ISD::VROTLI", X86vshiftimm>;
 def X86vrotri  : SDNode<"X86ISD::VROTRI", X86vshiftimm>;