Work around alloca(3) in fun_bc_call().#13
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ltratt merged 1 commit intoykjit:masterfrom Mar 31, 2026
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alloca(3) causes the frame to have dynamic size, which in-turn breaks stackmaps. For this reason, functions which use alloca(3) are `yk_outline`d by ykllvm. micropython avoids lots of heap allocation by storing small code states on the stack with alloca(3). This means we can't trace. This change nullifies the optimisation, so we always allocate code states on te GC heap. If you were to add `yk_unroll_safe` and `yk_indirect_inline` to `fun_bc_call()`, then it would not be `yk_outline` and we'd have a full definition in the AOR IR.
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alloca(3) causes the frame to have dynamic size, which in-turn breaks stackmaps. For this reason, functions which use alloca(3) are
yk_outlined by ykllvm.micropython avoids lots of heap allocation by storing small code states on the stack with alloca(3). This means we can't trace.
This change nullifies the optimisation, so we always allocate code states on te GC heap.
If you were to add
yk_unroll_safeandyk_indirect_inlinetofun_bc_call(), then it would not beyk_outlineand we'd have a full definition in the AOR IR.