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Ayke van Laethem
0565b7c0e0
On ARM, the stack has to be aligned to 8 bytes on function calls, but not necessarily within a function. Leaf functions can take advantage of this by not keeping the stack aligned so they can avoid pushing one register. However, because regular functions might expect an aligned stack, the interrupt controller will forcibly re-align the stack when an interrupt happens in such a leaf function (controlled by the STKALIGN flag, defaults to on). This means that stack size calculation (as used in TinyGo) needs to make sure this extra space for stack re-alignment is available. This commit fixes this by aligning the stack size that will be used for new goroutines. Additionally, it increases the stack canary size from 4 to 8 bytes, to keep the stack aligned. This is not strictly necessary but is required by the AAPCS so let's do it anyway just to be sure.