Modify the Unix signal handler to redirect execution to a Go sigpanic
function instead of printing an error and re-raising the signal.
The C signal handler modifies the ucontext to make the faulting
instruction appear to have called tinygo_sigpanic, which then calls
runtimePanic with the appropriate message.
Supported on all architectures TinyGo targets on Linux and Darwin:
x86_64, i386, aarch64, ARM, and MIPS. Also registers SIGFPE, which
was previously not handled at all.
Change hashmap set operations and channel send/close from
createRuntimeCall to createRuntimeInvoke. This places a setjmp
checkpoint before each call, allowing runtimePanicAt to safely
longjmp when these operations panic.
Emit fault checkpoints around compiler-generated runtime assertions so
runtimePanicAt can unwind through the existing defer/recover machinery
instead of aborting. This lets panics from bounds checks, type checks,
and other compiler-inserted runtime checks be recovered by deferred
functions.
Mark functions that call recover as noinline. Inlining such a function
into a deferred closure can make recover observe the wrong call context
and report success when it should return nil.
Addresses tinygo-org/tinygo issues 2759 and 3510.