[CIR] Add cir.std.find operation

This is going to be used to raise `cir.call`s to `std::find(...)` into
`cir.std.find`.

Author: bcardosolopes

clang/include/clang/CIR/Dialect/IR/CIRDialect.h

@@ -41,6 +41,7 @@ namespace impl {
 // corresponding trait classes.  This avoids them being template
 // instantiated/duplicated.
 LogicalResult verifySameFirstOperandAndResultType(Operation *op);
+LogicalResult verifySameFirstSecondOperandAndResultType(Operation *op);
 } // namespace impl
 
 /// This class provides verification for ops that are known to have the same
@@ -55,6 +56,18 @@ class SameFirstOperandAndResultType
   }
 };
 
+/// This class provides verification for ops that are known to have the same
+/// first operand and result type.
+///
+template <typename ConcreteType>
+class SameFirstSecondOperandAndResultType
+    : public TraitBase<ConcreteType, SameFirstSecondOperandAndResultType> {
+public:
+  static LogicalResult verifyTrait(Operation *op) {
+    return impl::verifySameFirstSecondOperandAndResultType(op);
+  }
+};
+
 } // namespace OpTrait
 
 namespace cir {

clang/include/clang/CIR/Dialect/IR/CIROps.td

@@ -2238,6 +2238,46 @@ def MemChrOp : CIR_Op<"libc.memchr"> {
   let hasVerifier = 0;
 }
 
+//===----------------------------------------------------------------------===//
+// StdFindOp
+//===----------------------------------------------------------------------===//
+
+def SameFirstSecondOperandAndResultType :
+  NativeOpTrait<"SameFirstSecondOperandAndResultType">;
+
+def StdFindOp : CIR_Op<"std.find", [SameFirstSecondOperandAndResultType]> {
+  let arguments = (ins FlatSymbolRefAttr:$original_fn,
+                       AnyType:$first,
+                       AnyType:$last,
+                       AnyType:$pattern);
+  let summary = "std:find()";
+  let results = (outs AnyType:$result);
+
+  let description = [{
+    Search for `pattern` in data range from `first` to `last`. This currently
+    maps to only one form of `std::find`. The `original_fn` operand tracks the
+    mangled named that can be used when lowering to a `cir.call`.
+
+    Example:
+
+    ```mlir
+    ...
+    %result = cir.std.find(@original_fn,
+                           %first : !T, %last : !T, %pattern : !P) -> !T
+    ```
+  }];
+
+  let assemblyFormat = [{
+    `(`
+      $original_fn
+      `,` $first `:` type($first)
+      `,` $last `:` type($last)
+      `,` $pattern `:` type($pattern)
+    `)` `->` type($result) attr-dict
+  }];
+  let hasVerifier = 0;
+}
+
 //===----------------------------------------------------------------------===//
 // FAbsOp
 //===----------------------------------------------------------------------===//

clang/lib/CIR/Dialect/IR/CIRDialect.cpp

@@ -2163,6 +2163,20 @@ mlir::OpTrait::impl::verifySameFirstOperandAndResultType(Operation *op) {
   return success();
 }
 
+LogicalResult
+mlir::OpTrait::impl::verifySameFirstSecondOperandAndResultType(Operation *op) {
+  if (failed(verifyAtLeastNOperands(op, 3)) || failed(verifyOneResult(op)))
+    return failure();
+
+  auto checkType = op->getResult(0).getType();
+  if (checkType != op->getOperand(0).getType() &&
+      checkType != op->getOperand(1).getType())
+    return op->emitOpError()
+           << "requires the same type for first operand and result";
+
+  return success();
+}
+
 //===----------------------------------------------------------------------===//
 // CIR attributes
 // FIXME: move all of these to CIRAttrs.cpp