Add constant + GetStructFieldRelocatable + start hint

pkg/hints/hint_codes/keccak_hint_codes.go

@@ -1,3 +1,5 @@
 package hint_codes
 
 const UNSAFE_KECCAK = "from eth_hash.auto import keccak\n\ndata, length = ids.data, ids.length\n\nif '__keccak_max_size' in globals():\n    assert length <= __keccak_max_size, \\\n        f'unsafe_keccak() can only be used with length<={__keccak_max_size}. ' \\\n        f'Got: length={length}.'\n\nkeccak_input = bytearray()\nfor word_i, byte_i in enumerate(range(0, length, 16)):\n    word = memory[data + word_i]\n    n_bytes = min(16, length - byte_i)\n    assert 0 <= word < 2 ** (8 * n_bytes)\n    keccak_input += word.to_bytes(n_bytes, 'big')\n\nhashed = keccak(keccak_input)\nids.high = int.from_bytes(hashed[:16], 'big')\nids.low = int.from_bytes(hashed[16:32], 'big')"
+
+const UNSAFE_KECCAK_FINALIZE = "from eth_hash.auto import keccak\nkeccak_input = bytearray()\nn_elms = ids.keccak_state.end_ptr - ids.keccak_state.start_ptr\nfor word in memory.get_range(ids.keccak_state.start_ptr, n_elms):\n    keccak_input += word.to_bytes(16, 'big')\nhashed = keccak(keccak_input)\nids.high = int.from_bytes(hashed[:16], 'big')\nids.low = int.from_bytes(hashed[16:32], 'big')"

pkg/hints/hint_utils/ids_manager.go

@@ -162,6 +162,35 @@ func (ids *IdsManager) GetStructFieldFelt(name string, field_off uint, vm *Virtu
 	return lambdaworks.Felt{}, ErrUnknownIdentifier(name)
 }
 
+/*
+	 Returns the value of an ids' field (given that the identifier is a sruct) as a Relocatable
+		For example:
+
+		struct shelter {
+			cats cat*
+			dogs dog*
+		}
+
+		to access each struct field, cats will be field 0 and dogs will be field 1, so to access them we can use:
+		ids_cats := ids.GetStructFieldFelt("shelter", 0, vm) or ids_cats := ids.Get("shelter", vm)
+		ids_dogs := ids.GetStructFieldFelt("shelter", 1, vm)
+*/
+func (ids *IdsManager) GetStructFieldRelocatable(name string, field_off uint, vm *VirtualMachine) (Relocatable, error) {
+	reference, ok := ids.References[name]
+	if ok {
+		val, ok := getStructFieldFromReference(&reference, field_off, ids.HintApTracking, vm)
+		if ok {
+			rel, is_rel := val.GetRelocatable()
+			if !is_rel {
+				return Relocatable{}, errors.Errorf("Identifier %s is not a Relocatable", name)
+			}
+			return rel, nil
+		}
+	}
+
+	return Relocatable{}, ErrUnknownIdentifier(name)
+}
+
 /*
 	 Inserts value into an ids' field (given that the identifier is a sruct)
 		For example:

pkg/hints/keccak_hints.go

@@ -71,3 +71,19 @@ func unsafeKeccak(ids IdsManager, vm *VirtualMachine, scopes ExecutionScopes) er
 	}
 	return ids.Insert("low", NewMaybeRelocatableFelt(low), vm)
 }
+
+func unsafeKeccakFinalize(ids IdsManager, vm *VirtualMachine, scopes ExecutionScopes) error {
+	// Fetch ids variables
+	startPtr, err := ids.GetStructFieldRelocatable("keccak_state", 0, vm)
+	if err != nil {
+		return err
+	}
+	endPtr, err := ids.GetStructFieldRelocatable("keccak_state", 1, vm)
+	if err != nil {
+		return err
+	}
+	n_elems, err := endPtr.Sub(startPtr)
+	if err != nil {
+		return err
+	}
+}