Fixed some bugs in stack unwinding metadata of runtime routines
Fixed some bugs in stack unwinding metadata of runtime routines

It's easy to forget that the assembler ignores the program's
control flow when computing the resulting CFA offset of the
various CFI_ADJUST directives. Note that unbalanced
CFI_ADJUST directives in one assembly routine cause all offsets
in all subsequent routines to be shifted by the corresponding
amount.

eliberis/ocaml,yunxing/ocaml,gerdstolpmann/ocaml,eliberis/ocaml,yunxing/ocaml,gerdstolpmann/ocaml,msprotz/ocaml,yunxing/ocaml,gerdstolpmann/ocaml,eliberis/ocaml,eliberis/ocaml,msprotz/ocaml,yunxing/ocaml,msprotz/ocaml,gerdstolpmann/ocaml,msprotz/ocaml,eliberis/ocaml,gerdstolpmann/ocaml,msprotz/ocaml,yunxing/ocaml