P. Chaque, . Représente-un-historique, and . Donc-une-trace, La fusion de S 1 et S 2 génère donc un état S merge dont le PC est défini par : PC merge = PC 1 ? PC 2 = (a 1 > 0 ? a 2 > 1) ? (a 1 > 20 ? a 2 > 10) Cette expression mathématique implique que la fusion

E. Effet, ? (a 1 > 20 ? a 2 > 10) représente aussi d'autres historiques d'exécution : ? (a 1 > 0 ? a 2 > 10)

E. Effet, expression (a 1 > 0 ? a 1 > 20) ? (a 2 > 1 ? a 2 > 10) définit un sur-ensemble contenant les traces faisables représentées par

. Ainsi, des comportements infaisables sont susceptibles d'apparaitre (les comportement engendrés par les historiques d'exécution qu'a introduit la disjonction de (a 1 > 0? a 2 > 10) et de (a 1 > 20? a 2 > 1)) Ce qui nuit considérablement à la précision des temps calculés. C'est pourquoi, la disjonction que nous utilisons n'est pas le simple opérateur mathématique, mais plutôt une disjonction entre PCs. Autrement dit, chaque PC est considéré comme une entité indivisible par l'opérateur de disjonction. Ainsi, durant notre analyse le PC merge est sauvegardé comme suit

B. La-figure-5 and C. , Les deux traces à gauche (A,B) sont générées durant l'exécution symbolique de la fonction acquisition La trace (C), en gris, est la trace obtenue après la fusion des deux précédentes traces. Durant l'exécution symbolique plusieurs traces convergent vers un état fortement similaire, Cet état est caractérisé par : ? (1) C'est un point de l'exécution qui rassemble plusieurs traces qui ont des historiques d'exécution différents

. Dans-la-figure-5, ) un fetcher (F) qui contient les instructions de 10 à 15) une unité de Branchement (BPU) qui contient l'instruction 8, (4) une unité de lecture et d'écriture mémoire (LSU) qui exécute l'instruction 6, (5) une unité d'achèvement qui stocke les résultats des exécutions des instructions 4 and 5, ) un dispatcher (D) qui dispatche les instructions 7 et 9) une mémoire cache d'instructions (IC) qui contient les instructions de 1 à 15

. Lorsque, nous identifions des états fortement similaires nous les fusionnons. Cette fusion n'a aucun impact sur les temps d'exécution calculés à posteriori

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