[mlir][ArmSVE] Add convert.from/to.svbool intrinsics (#68418)

These will be used in future pass to ensure that loads/stores of masks
are legal (as the LLVM backend does not support this for any type
smaller
than an svbool, which is vector<[16]xi1>).

Depends on #68399

Author: MacDue

mlir/include/mlir/Dialect/ArmSVE/IR/ArmSVE.td

@@ -30,6 +30,16 @@ def ArmSVE_Dialect : Dialect {
   }];
 }
 
+//===----------------------------------------------------------------------===//
+// ArmSVE type definitions
+//===----------------------------------------------------------------------===//
+
+def SVBool : ScalableVectorOfRankAndLengthAndType<
+  [1], [16], [I1]>;
+
+def SVEPredicate : ScalableVectorOfRankAndLengthAndType<
+  [1], [16, 8, 4, 2, 1], [I1]>;
+
 //===----------------------------------------------------------------------===//
 // ArmSVE op definitions
 //===----------------------------------------------------------------------===//
@@ -302,4 +312,18 @@ def ScalableMaskedDivFIntrOp :
   ArmSVE_IntrBinaryOverloadedOp<"fdiv">,
   Arguments<(ins AnyScalableVector, AnyScalableVector, AnyScalableVector)>;
 
+def ConvertFromSvboolIntrOp :
+  ArmSVE_IntrOp<"convert.from.svbool",
+    [TypeIs<"res", SVEPredicate>],
+    /*overloadedOperands=*/[],
+    /*overloadedResults=*/[0]>,
+  Arguments<(ins SVBool:$svbool)>;
+
+def ConvertToSvboolIntrOp :
+  ArmSVE_IntrOp<"convert.to.svbool",
+    [TypeIs<"res", SVBool>],
+    /*overloadedOperands=*/[0],
+    /*overloadedResults=*/[]>,
+    Arguments<(ins SVEPredicate:$mask)>;
+
 #endif // ARMSVE_OPS

mlir/test/Target/LLVMIR/arm-sve.mlir

@@ -272,3 +272,47 @@ llvm.func @get_vector_scale() -> i64 {
   %0 = "llvm.intr.vscale"() : () -> i64
   llvm.return %0 : i64
 }
+
+// CHECK-LABEL: @arm_sve_convert_from_svbool(
+// CHECK-SAME:                               <vscale x 16 x i1> %[[SVBOOL:[0-9]+]])
+llvm.func @arm_sve_convert_from_svbool(%nxv16i1 : vector<[16]xi1>) {
+  // CHECK: %[[RES0:.*]] = call <vscale x 8 x i1> @llvm.aarch64.sve.convert.from.svbool.nxv8i1(<vscale x 16 x i1> %[[SVBOOL]])
+  %res0 = "arm_sve.intr.convert.from.svbool"(%nxv16i1)
+    : (vector<[16]xi1>) -> vector<[8]xi1>
+  // CHECK: %[[RES1:.*]] = call <vscale x 4 x i1> @llvm.aarch64.sve.convert.from.svbool.nxv4i1(<vscale x 16 x i1> %[[SVBOOL]])
+  %res1 = "arm_sve.intr.convert.from.svbool"(%nxv16i1)
+    : (vector<[16]xi1>) -> vector<[4]xi1>
+  // CHECK: %[[RES2:.*]] = call <vscale x 2 x i1> @llvm.aarch64.sve.convert.from.svbool.nxv2i1(<vscale x 16 x i1> %[[SVBOOL]])
+  %res2 = "arm_sve.intr.convert.from.svbool"(%nxv16i1)
+    : (vector<[16]xi1>) -> vector<[2]xi1>
+  // CHECK: %[[RES3:.*]] = call <vscale x 1 x i1> @llvm.aarch64.sve.convert.from.svbool.nxv1i1(<vscale x 16 x i1> %[[SVBOOL]])
+  %res3 = "arm_sve.intr.convert.from.svbool"(%nxv16i1)
+    : (vector<[16]xi1>) -> vector<[1]xi1>
+  llvm.return
+}
+
+// CHECK-LABEL: arm_sve_convert_to_svbool(
+// CHECK-SAME:                            <vscale x 8 x i1> %[[P8:[0-9]+]],
+// CHECK-SAME:                            <vscale x 4 x i1> %[[P4:[0-9]+]],
+// CHECK-SAME:                            <vscale x 2 x i1> %[[P2:[0-9]+]],
+// CHECK-SAME:                            <vscale x 1 x i1> %[[P1:[0-9]+]])
+llvm.func @arm_sve_convert_to_svbool(
+                                       %nxv8i1  : vector<[8]xi1>,
+                                       %nxv4i1  : vector<[4]xi1>,
+                                       %nxv2i1  : vector<[2]xi1>,
+                                       %nxv1i1  : vector<[1]xi1>
+) {
+  // CHECK-NEXT: %[[RES0:.*]] = call <vscale x 16 x i1> @llvm.aarch64.sve.convert.to.svbool.nxv8i1(<vscale x 8 x i1> %[[P8]])
+  %res0 = "arm_sve.intr.convert.to.svbool"(%nxv8i1)
+    : (vector<[8]xi1>) -> vector<[16]xi1>
+  // CHECK-NEXT: %[[RES1:.*]] = call <vscale x 16 x i1> @llvm.aarch64.sve.convert.to.svbool.nxv4i1(<vscale x 4 x i1> %[[P4]])
+  %res1 = "arm_sve.intr.convert.to.svbool"(%nxv4i1)
+    : (vector<[4]xi1>) -> vector<[16]xi1>
+  // CHECK-NEXT: %[[RES2:.*]] = call <vscale x 16 x i1> @llvm.aarch64.sve.convert.to.svbool.nxv2i1(<vscale x 2 x i1> %[[P2]])
+  %res2 = "arm_sve.intr.convert.to.svbool"(%nxv2i1)
+    : (vector<[2]xi1>) -> vector<[16]xi1>
+  // CHECK-NEXT: %[[RES3:.*]] = call <vscale x 16 x i1> @llvm.aarch64.sve.convert.to.svbool.nxv1i1(<vscale x 1 x i1> %[[P1]])
+  %res3 = "arm_sve.intr.convert.to.svbool"(%nxv1i1)
+    : (vector<[1]xi1>) -> vector<[16]xi1>
+  llvm.return
+}