The bare quotative falaa is best construed as a conjunctive participle (see Feature 72 "Nominal and verbal conjunction"), which, though expressed by the bare verb in Sri Lanka Portuguese, is a distinct form in Tamil and Sinhala.
The complementizer falaa-tu is the perfective participle of 'say'.
Source: Smith 1974-5: 5337
Source: Smith 1974-5: 5272
Source: Smith 1974-5: 5273
Source: Smith 1974-5: 5345
Source: Smith 1977: 162
Source: Smith 1974-5: 3261
Source: Smith 1974-5: 5243
Source: Smith 1974-5: 5188