Modern processors predict the targets of an indirect branch regardless of the size of any jump table used to glean its target address. Moreover, branch predictors typically use resources limited by the number of actual targets that occur at run time.
This patch changes the semantics of the option -max-jump-table-size to limit the number of different targets instead of the number of entries in a jump table. Thus, it is now renamed to -max-jump-table-targets.
Before, when -max-jump-table-size was specified, it could happen that cluster jump tables could have targets used repeatedly, but each one was counted and typically resulted in tables with the same number of entries. With this patch, when specifying -max-jump-table-targets, tables may have different lengths, since the number of unique targets is counted towards the limit, but the number of unique targets in tables is the same, but for the last one containing the balance of targets.