[MLIR][LLVM][NFC] Use tblgen to automatically generate build functions

[jpienaar]

This moves the builder's C++ code from C++ to tablegen we normally try to keep C++ code in ODS files for minimum. If you want this generated you could implement the infer result type interface on this op and then you'd not need to define any custom builder AFAICS.

[Miss_Grape]

In D139770#3986487, @jpienaar wrote:

This moves the builder's C++ code from C++ to tablegen we normally try to keep C++ code in ODS files for minimum. If you want this generated you could implement the infer result type interface on this op and then you'd not need to define any custom builder AFAICS.

Sorry， i dont understand you, so what do you suggest for this modification?

[gysit]

Sorry， i dont understand you, so what do you suggest for this modification?

I think Jacques suggested two options:

1. either leave the builders in the C++ file rather than importing them into tablegen,

or

2. add an interface on the LLVM_ArithmeticCmpOp to infer the result types and generate the builders automatically without writing C++ in tablegen.

I think the right interface is InferTypeOpInterface which declares the inferReturnTypes method. I am not a 100% sure though.

mlir/include/mlir/Dialect/LLVMIR/LLVMOps.td

 // Other integer operations.
 def LLVM_ICmpOp : LLVM_ArithmeticCmpOp<"icmp", [Pure]> {
   let arguments = (ins ICmpPredicate:$predicate,
                    AnyTypeOf<[LLVM_ScalarOrVectorOf<AnyInteger>,
                               LLVM_ScalarOrVectorOf<LLVM_AnyPointer>]>:$lhs,
                    AnyTypeOf<[LLVM_ScalarOrVectorOf<AnyInteger>,
                               LLVM_ScalarOrVectorOf<LLVM_AnyPointer>]>:$rhs);
   let builders = [
-    OpBuilder<(ins "ICmpPredicate":$predicate, "Value":$lhs, "Value":$rhs)>
+    OpBuilder<(ins "ICmpPredicate":$predicate, "Value":$lhs, "Value":$rhs), [{
+      build($_builder, $_state, ::getI1SameShape(lhs.getType()),
+            predicate, lhs, rhs);
+    }]>
   ];
   let hasCustomAssemblyFormat = 1;
   string llvmInstName = "ICmp";
   string llvmBuilder = [{
     $res = builder.CreateICmp(getLLVMCmpPredicate($predicate), $lhs, $rhs);
   }];
   string mlirBuilder = [{
     auto *iCmpInst = cast<llvm::ICmpInst>(inst);

 def LLVM_FCmpOp : LLVM_ArithmeticCmpOp<"fcmp", [
     Pure, DeclareOpInterfaceMethods<FastmathFlagsInterface>]> {
   let arguments = (ins FCmpPredicate:$predicate,
                    LLVM_ScalarOrVectorOf<LLVM_AnyFloat>:$lhs,
                    LLVM_ScalarOrVectorOf<LLVM_AnyFloat>:$rhs,
                    DefaultValuedAttr<LLVM_FastmathFlagsAttr,
                                      "{}">:$fastmathFlags);
   let builders = [
-    OpBuilder<(ins "FCmpPredicate":$predicate, "Value":$lhs, "Value":$rhs)>
+    OpBuilder<(ins "FCmpPredicate":$predicate, "Value":$lhs, "Value":$rhs), [{
+      build($_builder, $_state, ::getI1SameShape(lhs.getType()),
+            predicate, lhs, rhs);
+    }]>
   ];
   let hasCustomAssemblyFormat = 1;
   string llvmInstName = "FCmp";
   string llvmBuilder = [{
     $res = builder.CreateFCmp(getLLVMCmpPredicate($predicate), $lhs, $rhs);
   }];
   // FIXME: Import fastmath flags.
   string mlirBuilder = [{

mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp

 static Type getI1SameShape(Type type) {
   Type i1Type = IntegerType::get(type.getContext(), 1);
   if (LLVM::isCompatibleVectorType(type))
     return LLVM::getVectorType(i1Type, LLVM::getVectorNumElements(type));
   return i1Type;
 }
 
 //===----------------------------------------------------------------------===//
-// Printing, parsing and builder for LLVM::CmpOp.
+// Printing and parsing for LLVM::CmpOp.
 //===----------------------------------------------------------------------===//
-
-void ICmpOp::build(OpBuilder &builder, OperationState &result,
-                   ICmpPredicate predicate, Value lhs, Value rhs) {
-  build(builder, result, getI1SameShape(lhs.getType()), predicate, lhs, rhs);
-}
-
-void FCmpOp::build(OpBuilder &builder, OperationState &result,
-                   FCmpPredicate predicate, Value lhs, Value rhs) {
-  build(builder, result, getI1SameShape(lhs.getType()), predicate, lhs, rhs);
-}
-
 void ICmpOp::print(OpAsmPrinter &p) {
   p << " \"" << stringifyICmpPredicate(getPredicate()) << "\" " << getOperand(0)
     << ", " << getOperand(1);
   p.printOptionalAttrDict((*this)->getAttrs(), {"predicate"});
   p << " : " << getLhs().getType();
 }
 
 void FCmpOp::print(OpAsmPrinter &p) {