This new logic tracks when an unconditional jump/raise occurs in the
emitted code stream (bytecode or native machine code) and suppresses all
subsequent code, until a label is assigned. This eliminates a lot of
cases of dead code, with relatively simple logic.
This commit combined with the previous one (that removed the existing
dead-code finding logic) has the following code size change:
bare-arm: -16 -0.028%
minimal x86: -60 -0.036%
unix x64: -368 -0.070%
unix nanbox: -80 -0.017%
stm32: -204 -0.052% PYBV10
cc3200: +0 +0.000%
esp8266: -232 -0.033% GENERIC
esp32: -224 -0.015% GENERIC[incl -40(data)]
mimxrt: -192 -0.054% TEENSY40
renesas-ra: -200 -0.032% RA6M2_EK
nrf: +28 +0.015% pca10040
rp2: -256 -0.050% PICO
samd: -12 -0.009% ADAFRUIT_ITSYBITSY_M4_EXPRESS
Signed-off-by: Damien George <damien@micropython.org>
