[mlir][ODS] Omit printing default-valued attributes in oilists (#68880)

This makes these match the behaviour of optional attributes (which are
omitted when they are their default value of none). This allows for
concise assembly formats without a custom printer.

An extra print of " " is also removed, this does change any existing
uses of oilists, but if the parameter before the oilist is optional,
that would previously add an extra space.

This #68694 + some fixes for the MLIR Python tests, unfortunately GitHub
does not allow re-opening PRs 😕

Author: MacDue

flang/test/Lower/OpenMP/FIR/atomic-read.f90

@@ -14,7 +14,7 @@
 !CHECK: %[[VAR_X:.*]] = fir.alloca i32 {bindc_name = "x", uniq_name = "_QFEx"}
 !CHECK: %[[VAR_Y:.*]] = fir.alloca i32 {bindc_name = "y", uniq_name = "_QFEy"}
 !CHECK: omp.atomic.read %[[VAR_X]] = %[[VAR_Y]] memory_order(acquire)  hint(uncontended) : !fir.ref<i32>, i32
-!CHECK: omp.atomic.read %[[VAR_A]] = %[[VAR_B]] memory_order(relaxed) hint(none)  : !fir.ref<!fir.char<1>>, !fir.char<1>
+!CHECK: omp.atomic.read %[[VAR_A]] = %[[VAR_B]] memory_order(relaxed) : !fir.ref<!fir.char<1>>, !fir.char<1>
 !CHECK: omp.atomic.read %[[VAR_C]] = %[[VAR_D]] memory_order(seq_cst)  hint(contended) : !fir.ref<!fir.logical<4>>, !fir.logical<4>
 !CHECK: omp.atomic.read %[[VAR_E]] = %[[VAR_F]] hint(speculative) : !fir.ref<!fir.char<1,8>>, !fir.char<1,8>
 !CHECK: omp.atomic.read %[[VAR_G]] = %[[VAR_H]] hint(nonspeculative) : !fir.ref<f32>, f32

flang/test/Lower/OpenMP/FIR/critical.f90

@@ -2,7 +2,7 @@
 !RUN: %flang_fc1 -emit-fir -fopenmp %s -o - | fir-opt --fir-to-llvm-ir | FileCheck %s --check-prefix="OMPDialect"
 !RUN: %flang_fc1 -emit-fir -fopenmp %s -o - | fir-opt --fir-to-llvm-ir | tco | FileCheck %s --check-prefix="LLVMIR"
 
-!OMPDialect: omp.critical.declare @help2 hint(none)
+!OMPDialect: omp.critical.declare @help2
 !OMPDialect: omp.critical.declare @help1 hint(contended)
 
 subroutine omp_critical()

flang/test/Lower/OpenMP/critical.f90

@@ -1,6 +1,6 @@
 !RUN: %flang_fc1 -emit-hlfir -fopenmp %s -o - | FileCheck %s
 
-!CHECK: omp.critical.declare @help2 hint(none)
+!CHECK: omp.critical.declare @help2
 !CHECK: omp.critical.declare @help1 hint(contended)
 
 subroutine omp_critical()

mlir/test/Conversion/OpenMPToLLVM/convert-to-llvmir.mlir

@@ -90,7 +90,7 @@ func.func @wsloop(%arg0: index, %arg1: index, %arg2: index, %arg3: index, %arg4:
 // CHECK-LABEL: @atomic_write
 // CHECK: (%[[ARG0:.*]]: !llvm.ptr<i32>)
 // CHECK: %[[VAL0:.*]] = llvm.mlir.constant(1 : i32) : i32
-// CHECK: omp.atomic.write %[[ARG0]] = %[[VAL0]] hint(none) memory_order(relaxed) : !llvm.ptr<i32>, i32
+// CHECK: omp.atomic.write %[[ARG0]] = %[[VAL0]] memory_order(relaxed) : !llvm.ptr<i32>, i32
 func.func @atomic_write(%a: !llvm.ptr<i32>) -> () {
   %1 = arith.constant 1 : i32
   omp.atomic.write %a = %1 hint(none) memory_order(relaxed) : !llvm.ptr<i32>, i32
@@ -474,4 +474,4 @@ llvm.func @_QPtarget_map_with_bounds(%arg0: !llvm.ptr<i32>, %arg1: !llvm.ptr<arr
     omp.terminator
   }
   llvm.return
-}
+}

mlir/test/Dialect/OpenMP/ops.mlir

@@ -831,7 +831,7 @@ omp.critical.declare @mutex6 hint(contended, nonspeculative)
 omp.critical.declare @mutex7 hint(uncontended, speculative)
 // CHECK: omp.critical.declare @mutex8 hint(contended, speculative)
 omp.critical.declare @mutex8 hint(contended, speculative)
-// CHECK: omp.critical.declare @mutex9 hint(none)
+// CHECK: omp.critical.declare @mutex9
 omp.critical.declare @mutex9 hint(none)
 // CHECK: omp.critical.declare @mutex10
 omp.critical.declare @mutex10
@@ -909,7 +909,7 @@ func.func @omp_atomic_read(%v: memref<i32>, %x: memref<i32>) {
   omp.atomic.read %v = %x hint(nonspeculative, contended) : memref<i32>, i32
   // CHECK: omp.atomic.read %[[v]] = %[[x]] memory_order(seq_cst) hint(contended, speculative) : memref<i32>, i32
   omp.atomic.read %v = %x hint(speculative, contended) memory_order(seq_cst) : memref<i32>, i32
-  // CHECK: omp.atomic.read %[[v]] = %[[x]] memory_order(seq_cst) hint(none) : memref<i32>, i32
+  // CHECK: omp.atomic.read %[[v]] = %[[x]] memory_order(seq_cst) : memref<i32>, i32
   omp.atomic.read %v = %x hint(none) memory_order(seq_cst) : memref<i32>, i32
   return
 }
@@ -927,7 +927,7 @@ func.func @omp_atomic_write(%addr : memref<i32>, %val : i32) {
   omp.atomic.write %addr = %val memory_order(relaxed) : memref<i32>, i32
   // CHECK: omp.atomic.write %[[ADDR]] = %[[VAL]] hint(uncontended, speculative) : memref<i32>, i32
   omp.atomic.write %addr = %val hint(speculative, uncontended) : memref<i32>, i32
-  // CHECK: omp.atomic.write %[[ADDR]] = %[[VAL]] hint(none) : memref<i32>, i32
+  // CHECK: omp.atomic.write %[[ADDR]] = %[[VAL]] : memref<i32>, i32
   omp.atomic.write %addr = %val hint(none) : memref<i32>, i32
   return
 }
@@ -1004,7 +1004,7 @@ func.func @omp_atomic_update(%x : memref<i32>, %expr : i32, %xBool : memref<i1>,
     omp.yield(%const:i32)
   }
 
-  // CHECK: omp.atomic.update hint(none) %[[X]] : memref<i32>
+  // CHECK: omp.atomic.update %[[X]] : memref<i32>
   // CHECK-NEXT: (%[[XVAL:.*]]: i32):
   // CHECK-NEXT:   %[[NEWVAL:.*]] = llvm.add %[[XVAL]], %[[EXPR]] : i32
   // CHECK-NEXT:   omp.yield(%[[NEWVAL]] : i32)
@@ -1181,7 +1181,7 @@ func.func @omp_atomic_capture(%v: memref<i32>, %x: memref<i32>, %expr: i32) {
     omp.atomic.write %x = %expr : memref<i32>, i32
   }
 
-  // CHECK: omp.atomic.capture hint(none) {
+  // CHECK: omp.atomic.capture {
   // CHECK-NEXT: omp.atomic.update %[[x]] : memref<i32>
   // CHECK-NEXT: (%[[xval:.*]]: i32):
   // CHECK-NEXT:   %[[newval:.*]] = llvm.add %[[xval]], %[[expr]] : i32

mlir/test/python/dialects/transform_structured_ext.py

@@ -439,7 +439,7 @@ def testTileToForallCompact(target):
     structured.TileUsingForallOp(matmul, num_threads=[2, 3, 4])
     # CHECK-LABEL: TEST: testTileToForallCompact
     # CHECK: = transform.structured.tile_using_forall
-    # CHECK-SAME: num_threads [2, 3, 4] tile_sizes []
+    # CHECK-SAME: num_threads [2, 3, 4]
     # CHECK-SAME: (!transform.op<"linalg.matmul">) -> (!transform.any_op, !transform.any_op)
 
 
@@ -454,7 +454,7 @@ def testTileToForallLoopsAndTileOpTypes(target):
     )
     # CHECK-LABEL: TEST: testTileToForallLoopsAndTileOpTypes
     # CHECK: = transform.structured.tile_using_forall
-    # CHECK-SAME: num_threads [2, 3, 4] tile_sizes []
+    # CHECK-SAME: num_threads [2, 3, 4]
     # CHECK-SAME: (!transform.any_op) -> (!transform.op<"scf.forall">, !transform.op<"linalg.matmul">)
 
 
@@ -464,7 +464,7 @@ def testTileToForallTileSizes(target):
     structured.TileUsingForallOp(target, tile_sizes=[2, 3, 4])
     # CHECK-LABEL: TEST: testTileToForallTileSizes
     # CHECK: = transform.structured.tile_using_forall
-    # CHECK-SAME: num_threads [] tile_sizes [2, 3, 4]
+    # CHECK-SAME: tile_sizes [2, 3, 4]
 
 
 @run

mlir/test/python/dialects/transform_vector_ext.py

@@ -94,30 +94,24 @@ def enum_configurable_patterns():
     )
 
     # CHECK: transform.apply_patterns.vector.lower_transpose
-    # CHECK-SAME: lowering_strategy = eltwise
-    # CHECK-SAME: avx2_lowering_strategy = false
     vector.ApplyLowerTransposePatternsOp()
     # CHECK: transform.apply_patterns.vector.lower_transpose
-    # CHECK-SAME: lowering_strategy = eltwise
-    # CHECK-SAME: avx2_lowering_strategy = false
+    # This is the default strategy, not printed.
     vector.ApplyLowerTransposePatternsOp(
         lowering_strategy=vector.VectorTransposeLowering.EltWise
     )
     # CHECK: transform.apply_patterns.vector.lower_transpose
     # CHECK-SAME: lowering_strategy = flat_transpose
-    # CHECK-SAME: avx2_lowering_strategy = false
     vector.ApplyLowerTransposePatternsOp(
         lowering_strategy=vector.VectorTransposeLowering.Flat
     )
     # CHECK: transform.apply_patterns.vector.lower_transpose
     # CHECK-SAME: lowering_strategy = shuffle_1d
-    # CHECK-SAME: avx2_lowering_strategy = false
     vector.ApplyLowerTransposePatternsOp(
         lowering_strategy=vector.VectorTransposeLowering.Shuffle1D
     )
     # CHECK: transform.apply_patterns.vector.lower_transpose
     # CHECK-SAME: lowering_strategy = shuffle_16x16
-    # CHECK-SAME: avx2_lowering_strategy = false
     vector.ApplyLowerTransposePatternsOp(
         lowering_strategy=vector.VectorTransposeLowering.Shuffle16x16
     )

mlir/tools/mlir-tblgen/OpFormatGen.cpp

@@ -2009,6 +2009,16 @@ static void genEnumAttrPrinter(const NamedAttribute *var, const Operator &op,
           "  }\n";
 }
 
+/// Generate a check that a DefaultValuedAttr has a value that is non-default.
+static void genNonDefaultValueCheck(MethodBody &body, const Operator &op,
+                                    AttributeVariable &attrElement) {
+  FmtContext fctx;
+  Attribute attr = attrElement.getVar()->attr;
+  fctx.withBuilder("::mlir::OpBuilder((*this)->getContext())");
+  body << " && " << op.getGetterName(attrElement.getVar()->name) << "Attr() != "
+       << tgfmt(attr.getConstBuilderTemplate(), &fctx, attr.getDefaultValue());
+}
+
 /// Generate the check for the anchor of an optional group.
 static void genOptionalGroupPrinterAnchor(FormatElement *anchor,
                                           const Operator &op,
@@ -2042,12 +2052,7 @@ static void genOptionalGroupPrinterAnchor(FormatElement *anchor,
         if (attr.hasDefaultValue()) {
           // Consider a default-valued attribute as present if it's not the
           // default value.
-          FmtContext fctx;
-          fctx.withBuilder("::mlir::OpBuilder((*this)->getContext())");
-          body << " && " << op.getGetterName(element->getVar()->name)
-               << "Attr() != "
-               << tgfmt(attr.getConstBuilderTemplate(), &fctx,
-                        attr.getDefaultValue());
+          genNonDefaultValueCheck(body, op, *element);
           return;
         }
         llvm_unreachable("attribute must be optional or default-valued");
@@ -2158,7 +2163,6 @@ void OperationFormat::genElementPrinter(FormatElement *element,
 
   // Emit the OIList
   if (auto *oilist = dyn_cast<OIListElement>(element)) {
-    genLiteralPrinter(" ", body, shouldEmitSpace, lastWasPunctuation);
     for (auto clause : oilist->getClauses()) {
       LiteralElement *lelement = std::get<0>(clause);
       ArrayRef<FormatElement *> pelement = std::get<1>(clause);
@@ -2170,8 +2174,14 @@ void OperationFormat::genElementPrinter(FormatElement *element,
       for (VariableElement *var : vars) {
         TypeSwitch<FormatElement *>(var)
             .Case([&](AttributeVariable *attrEle) {
-              body << " || " << op.getGetterName(attrEle->getVar()->name)
+              body << " || (" << op.getGetterName(attrEle->getVar()->name)
                    << "Attr()";
+              Attribute attr = attrEle->getVar()->attr;
+              if (attr.hasDefaultValue()) {
+                // Don't print default-valued attributes.
+                genNonDefaultValueCheck(body, op, *attrEle);
+              }
+              body << ")";
             })
             .Case([&](OperandVariable *ele) {
               if (ele->getVar()->isVariadic()) {