Enums.td

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//===-- Enums.td -------------------------------------------*- tablegen -*-===//
//
// Part of the LLZK Project, under the Apache License v2.0.
// See LICENSE.txt for license information.
// Copyright 2026 Project LLZK
// SPDX-License-Identifier: Apache-2.0
//
//===----------------------------------------------------------------------===//
 
#ifndef LLZK_CAST_ENUMS
#define LLZK_CAST_ENUMS
 
include "mlir/IR/EnumAttr.td"
 
def OverflowSemanticsDescription {
  string r =
      "Specifies how a cast handles a source value outside the target's safe "
      "range. For a felt target with prime `p`, the safe range is `[0, p-1]`. "
      "For an index target with bitwidth `N`, it is `[0, 2^(N-1)-1]`.";
}
 
def LLZK_OverflowSemantics
    : I32EnumAttr<"OverflowSemantics", OverflowSemanticsDescription.r,
                  [
                      // Assert (default): Fail when the source value is outside
                      // the safe range.
                      I32EnumAttrCase<"ASSERT", 0, "assert">,
                      // Saturate: Clamp to the safe range.
                      I32EnumAttrCase<"SATURATE", 1, "sat">,
                      // Wrap: Reduce modulo `p` for `tofelt` or modulo
                      // `2^(N-1)` for `toindex`, keeping the result in the
                      // index safe range.
                      I32EnumAttrCase<"WRAP", 2, "wrap">,
                      // Truncate: Keep the low bits. For `tofelt`, keep
                      // `bitwidth(p)` bits, then reduce modulo `p` to stay in
                      // the safe range. For `toindex`, keep `N-1` bits so the
                      // sign bit is zero.
                      I32EnumAttrCase<"TRUNCATE", 3, "trunc">,
]> {
  let genSpecializedAttr = 0;
  let cppNamespace = "::llzk::cast";
}
 
#endif // LLZK_CAST_ENUMS