In HardwareSerial::_rx_complete_irq, don't use int for buffer index #1870
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This was already fixed for HardwareSerial.cpp in arduino#1863, but there was one more case hidden in HardwareSerial_private.h. The index attributes have been uint8_t for a while, so there is no point in using int for local variables. This should allow the compiler to generate slightly more efficient code, but (at least on gcc 4.8.2) it also confuses the register allocator, causing this change to increase code size by 2 bytes instead due to extra push/pop instructions (but this will probably change in the future if the compiler improves).
This was referenced Feb 18, 2014
cmaglie
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Feb 18, 2014
In HardwareSerial::_rx_complete_irq, don't use int for buffer index
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This was already fixed for HardwareSerial.cpp in #1863, but there was
one more case hidden in HardwareSerial_private.h.
The index attributes have been uint8_t for a while, so there is no point
in using int for local variables. This should allow the compiler to
generate slightly more efficient code, but (at least on gcc 4.8.2) it
also confuses the register allocator, causing this change to increase
code size by 2 bytes instead due to extra push/pop instructions (but
this will probably change in the future if the compiler improves).