[mlir][llvm] Add `llvm.intr.is.fpclass`

[Mogball]

Summary

This intrinsic allows testing for inf, nan, etc. on floating point
values.

[Mogball]

review comment

[Mogball]

fix diff

[rriddle]

Test?

[Mogball]

add test

mlir/include/mlir/Dialect/LLVMIR/LLVMIntrinsicOps.td

LLVM_OneResultIntrOp<func, [], [0],
            !listconcat([NoSideEffect], traits)> {
   let arguments = (ins LLVM_Type:$in, I1:$zero_undefined);
 }
 
 def LLVM_AbsOp : LLVM_OneResultIntrOp<"abs", [], [0], [NoSideEffect]> {
   let arguments = (ins LLVM_Type:$in, I1:$is_int_min_poison);
 }
 
+def LLVM_IsFPClass : LLVM_OneResultIntrOp<"is.fpclass", [], [0],
+                                          [NoSideEffect]> {
+  let arguments = (ins LLVM_Type:$in, I32:$bit);
+}
+
 def LLVM_CopySignOp : LLVM_BinarySameArgsIntrinsicOp<"copysign">;
 def LLVM_CosOp : LLVM_UnaryIntrinsicOp<"cos">;
 def LLVM_ExpOp : LLVM_UnaryIntrinsicOp<"exp">;
 def LLVM_Exp2Op : LLVM_UnaryIntrinsicOp<"exp2">;
 def LLVM_FAbsOp : LLVM_UnaryIntrinsicOp<"fabs">;
 def LLVM_FCeilOp : LLVM_UnaryIntrinsicOp<"ceil">;
 def LLVM_FFloorOp : LLVM_UnaryIntrinsicOp<"floor">;
 def LLVM_FMAOp : LLVM_TernarySameArgsIntrinsicOp<"fma">;

mlir/test/Target/LLVMIR/llvmir-intrinsics.mlir

llvm.func @intrinsics(%arg0: f32, %arg1: f32, %arg2: vector<8xf32>, %arg3: !llvm.ptr<i8>) {
   "llvm.intr.fma"(%arg0, %arg1, %arg0) : (f32, f32, f32) -> f32
   // CHECK: call <8 x float> @llvm.fma.v8f32
   "llvm.intr.fma"(%arg2, %arg2, %arg2) : (vector<8xf32>, vector<8xf32>, vector<8xf32>) -> vector<8xf32>
   // CHECK: call void @llvm.prefetch.p0(ptr %3, i32 0, i32 3, i32 1)
   "llvm.intr.prefetch"(%arg3, %c0, %c3, %c1) : (!llvm.ptr<i8>, i32, i32, i32) -> ()
   llvm.return
 }
 
+// CHECK-LABEL: @fpclass_test
+llvm.func @fpclass_test(%arg0: f32) -> i1 {
+  %checkNan = llvm.mlir.constant(0 : i32) : i32
+  // CHECK: call i1 @llvm.is.fpclass
+  %0 = "llvm.intr.is.fpclass"(%arg0, %checkNan) : (f32, i32) -> i1
+  llvm.return %0 : i1
+}
+
 // CHECK-LABEL: @exp_test
 llvm.func @exp_test(%arg0: f32, %arg1: vector<8xf32>) {
   // CHECK: call float @llvm.exp.f32
   "llvm.intr.exp"(%arg0) : (f32) -> f32
   // CHECK: call <8 x float> @llvm.exp.v8f32
   "llvm.intr.exp"(%arg1) : (vector<8xf32>) -> vector<8xf32>
   llvm.return
 }