[GlobalISel] Add a G_FNEARBYINT opcode

For eventually selecting llvm.nearbyint. Equivalent to the SelectionDAG
nearbyint node.

Update legalizer-info-validation.mir.

Differential Revision: https://reviews.llvm.org/D60921

llvm-svn: 359201

Author: Jessica Paquette

llvm/include/llvm/Support/TargetOpcodes.def

@@ -539,6 +539,9 @@ HANDLE_TARGET_OPCODE(G_FFLOOR)
 /// Floating point round to next integer.
 HANDLE_TARGET_OPCODE(G_FRINT)
 
+/// Floating point round to nearest integer.
+HANDLE_TARGET_OPCODE(G_FNEARBYINT)
+
 /// Generic AddressSpaceCast.
 HANDLE_TARGET_OPCODE(G_ADDRSPACE_CAST)
 

llvm/include/llvm/Target/GenericOpcodes.td

@@ -599,6 +599,13 @@ def G_FRINT : GenericInstruction {
   let hasSideEffects = 0;
 }
 
+// Floating point round to the nearest integer.
+def G_FNEARBYINT : GenericInstruction {
+  let OutOperandList = (outs type0:$dst);
+  let InOperandList = (ins type0:$src1);
+  let hasSideEffects = 0;
+}
+
 //------------------------------------------------------------------------------
 // Opcodes for LLVM Intrinsics
 //------------------------------------------------------------------------------

llvm/include/llvm/Target/GlobalISel/SelectionDAGCompat.td

@@ -96,6 +96,7 @@ def : GINodeEquiv<G_FABS, fabs>;
 def : GINodeEquiv<G_FSQRT, fsqrt>;
 def : GINodeEquiv<G_FFLOOR, ffloor>;
 def : GINodeEquiv<G_FRINT, frint>;
+def : GINodeEquiv<G_FNEARBYINT, fnearbyint>;
 
 // Broadly speaking G_LOAD is equivalent to ISD::LOAD but there are some
 // complications that tablegen must take care of. For example, Predicates such

llvm/test/CodeGen/AArch64/GlobalISel/legalizer-info-validation.mir

@@ -350,6 +350,9 @@
 #
 # DEBUG-NEXT: G_FRINT (opcode {{[0-9]+}}): 1 type index
 # DEBUG: .. type index coverage check SKIPPED: user-defined predicate detected
+#
+# DEBUG-NEXT: G_FNEARBYINT (opcode {{[0-9]+}}): 1 type index
+# DEBUG: .. type index coverage check SKIPPED: no rules defined
 
 # CHECK-NOT: ill-defined