Improvements to non 32-bit exception handler #7816
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resets. It seems you should not use input registers for scratch registers. Add an extra output register instead. No code size increase. Light refactoring for readability Added "C" reference code for Extended ASM Save two cycles by loading a0 early in exc-c-wrapper-handler.S Use optimization O2 Net change in size, 0 bytes with optimization. Save 4 bytes w/o Optimization. With changes and "O2" save 3 cycles on write and 6 cycles on read.
earlephilhower
approved these changes
Jan 8, 2021
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Extended ASM got fussy when using different optimizations. ie. HWDT resets. It seems you should not use input registers for scratch registers. Fixed by adding an extra output register for temporary values. No code size increase. Now works with different optimizations.
Light refactoring for readability
Added "C" reference code for Extended ASM
Save two cycles by loading
a0early inexc-c-wrapper-handler.SUse optimization
O2Net change in size, 0 bytes with optimization. Save 4 bytes w/o Optimization.
With changes and
O2save 3 cycles on write and 6 cycles on read.