Regarding Pascal for the IBM PC. In its day, Borland Turbo Pascal was particularly fast.

But C existed as well. 

In 1982 I was building an ethernet telephone at PARC and used the 8088, mostly because
they were cheap (due to the PC) and because we had an internal C compiler for it.
I felt C was the necessary language, because that’s what we used on V7 at Stanford.

-L