Flattens case structures as nyacc is giving consecutive cases as a
nested block like:
(case testA
(case testB
(case testC BODY)))
We convert to:
((case testA (expr-stmt))
(case testB (expr-stmt))
(case testC BODY))
And then treat them as independent cases. For the fallthrough we just
add a jump to each case's body right before its clause (each of the case
blocks is responsible of adding its own jump to its body):
// This doesn't have it because it's the first
CASE1:
testA
CASE1_BODY:
goto CASE2_BODY
CASE2:
testB
CASE2_BODY:
goto CASE3_BODY
CASE3:
testB
CASE3_BODY:
This enables complex fallthrough schemes comparing to what was done
before.
* module/mescc/compile.scm (ast->info)[switch]{flatten-cases}: New
variable.
(ast->info)[switch]{statements}: Use flatten-cases on it.
(switch->expr): Remove unneeded matchers and add jumps to body.
* build-aux/check-mescc.sh(xfail-tests): Remove
lib/tests/scaffold/66-local-char-array.c.