[mlir] Add BoolArrayAttr in Tablegen + Builder support

[mehdi_amini]

Note though that all these "array attributes" are much less efficient than DenseAttribute I believe.

[rriddle]

In D80090#2040848, @mehdi_amini wrote:

Note though that all these "array attributes" are much less efficient than DenseAttribute I believe.

Extremely inefficient.

[rriddle]

In D80090#2058237, @rriddle wrote:

In D80090#2040848, @mehdi_amini wrote:

Note though that all these "array attributes" are much less efficient than DenseAttribute I believe.

Extremely inefficient.

It isn't as bad for BoolAttr because we already cache the true/false attribute values on context construction so lookup for those is "free". BoolArrayAttr is still worse in memory(because it needs to store 1 word per element as opposed to 1 bit) and execution time(needs to do more pointer chasing when checking elements. In general though ArrayAttr is much much worse than DenseElementsAttr when storing integer/float/complex/string data and should be discouraged.

mlir/include/mlir/IR/Builders.h

public:
 
   /// Tensor-typed DenseIntElementsAttr getters. `values` can be empty.
   /// These are generally preferable for representing general lists of integers
   /// as attributes.
   DenseIntElementsAttr getI32TensorAttr(ArrayRef<int32_t> values);
   DenseIntElementsAttr getI64TensorAttr(ArrayRef<int64_t> values);
 
   ArrayAttr getAffineMapArrayAttr(ArrayRef<AffineMap> values);
+  ArrayAttr getBoolArrayAttr(ArrayRef<bool> values);
   ArrayAttr getI32ArrayAttr(ArrayRef<int32_t> values);
   ArrayAttr getI64ArrayAttr(ArrayRef<int64_t> values);
   ArrayAttr getIndexArrayAttr(ArrayRef<int64_t> values);
   ArrayAttr getF32ArrayAttr(ArrayRef<float> values);
   ArrayAttr getF64ArrayAttr(ArrayRef<double> values);
   ArrayAttr getStrArrayAttr(ArrayRef<StringRef> values);
 
   // Affine expressions and affine maps.

mlir/include/mlir/IR/OpBase.td

And<[
                              SubstLeaves<"$_self", "attr", element.predicate>,
                           "; })">]>,
     description> {
   let constBuilderCall = "$_builder.getArrayAttr($0)";
 
   Attr elementAttr = element;
 }
 
+def BoolArrayAttr : TypedArrayAttrBase<BoolAttr,
+                                      "1-bit boolean array attribute"> {
+  let constBuilderCall = "$_builder.getBoolArrayAttr($0)";
+}
 def I32ArrayAttr : TypedArrayAttrBase<I32Attr,
                                       "32-bit integer array attribute"> {
   let constBuilderCall = "$_builder.getI32ArrayAttr($0)";
 }
 def I64ArrayAttr : TypedArrayAttrBase<I64Attr,
                                       "64-bit integer array attribute"> {
   let constBuilderCall = "$_builder.getI64ArrayAttr($0)";
 }

mlir/lib/IR/Builders.cpp

FlatSymbolRefAttr Builder::getSymbolRefAttr(StringRef value) {
   return SymbolRefAttr::get(value, getContext());
 }
 SymbolRefAttr
 Builder::getSymbolRefAttr(StringRef value,
                           ArrayRef<FlatSymbolRefAttr> nestedReferences) {
   return SymbolRefAttr::get(value, nestedReferences, getContext());
 }
 
+ArrayAttr Builder::getBoolArrayAttr(ArrayRef<bool> values) {
+  auto attrs = llvm::to_vector<8>(llvm::map_range(
+      values, [this](bool v) -> Attribute { return getBoolAttr(v); }));
+  return getArrayAttr(attrs);
+}
+
 ArrayAttr Builder::getI32ArrayAttr(ArrayRef<int32_t> values) {
   auto attrs = llvm::to_vector<8>(llvm::map_range(
       values, [this](int32_t v) -> Attribute { return getI32IntegerAttr(v); }));
   return getArrayAttr(attrs);
 }
-
 ArrayAttr Builder::getI64ArrayAttr(ArrayRef<int64_t> values) {
   auto attrs = llvm::to_vector<8>(llvm::map_range(
       values, [this](int64_t v) -> Attribute { return getI64IntegerAttr(v); }));
   return getArrayAttr(attrs);
 }
 
 ArrayAttr Builder::getIndexArrayAttr(ArrayRef<int64_t> values) {
   auto attrs = llvm::to_vector<8>(