I'm trying to figure out how to count syllables in medieval Galician-Portuguese cantigas. I've tried to find it in the book A poesía lírica galego-portuguesa by Giuseppe Tavani, which I found in my university library. It's a little difficult book for me to understand because it's written in Galician, a language I don't really know. It's in fact a translation: the original is in Italian and I would understand it much better, but it's impossible to find. In any case, it doesn't seem that such book contains any reference to how to count syllables in verses, but it may also be that I am not able to find it.
In the E-Dicionário de Termos Literários, coord. by Carlos Ceia, I have found an explanation about the Portuguese system:
sistema de versificação da língua portuguesa (que conta as sílabas poéticas até a última sílaba tônica, excluindo a última mais fraca)
That is,
versification system of the Portuguese language (which counts the poetic syllables up to the last stressed syllable, excluding the last weakest one)
I imagine it's the same for Galician-Portuguese medieval lyric, but I'm not completely sure. Can anyone confirm this?