Stack corruption

[celerizer]

The Stride graphics demo does not work correctly due to the y_pos iterator used by st_gfx_image not being placed in the correct place on the stack. Investigate behavior of opcodes 6E and 6F.

[FreeSanubis]

The Stride graphics demo does not work correctly due to the y_pos iterator used by st_gfx_image not being placed in the correct place on the stack. Investigate behavior of opcodes 6E and 6F.

Looks like opcodes 6E and 6F woke up this morning and collectively decided, "Nah, stack discipline is for other CPUs." Apparently y_pos took an unscheduled vacation to the wrong part of the stack, and now the graphics demo is expressing its artistic interpretation of correctness. Time to go spelunking through the emulator and find out which opcode is gaslighting us.