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When `consume_fuel` is enabled, `FuncEnvironment` caches the in-flight fuel counter in a function-local Cranelift SSA `Variable` (`self.fuel_var`) and synchronizes it with `VMStoreContext::fuel_consumed` across calls, returns, and exception handlers. Previously, stack-switching instructions (`resume`, `resume_throw`, `resume_throw_ref`, `suspend`, and `switch`) did not flush/save `self.fuel_var` before switching stacks or reload `self.fuel_var` upon returning or resuming, and `translate_resume_impl` did not reload `self.fuel_var` at the entry of `suspend_block` before dispatching to `(on $tag $label)` handler blocks. As a result, fuel consumed inside a continuation was overwritten whenever control switched back to the parent or target stack. Save `self.fuel_var` in `fuel_before_op` prior to `resume*`, `suspend`, and `switch`, reload `self.fuel_var` in `fuel_after_op` on normal return/wake-up, and call `env.on_catch_block_entry(builder)` at the start of `suspend_block`. Assisted-by: Gemini
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When
consume_fuelis enabled,FuncEnvironmentcaches the in-flight fuel counter in a function-local Cranelift SSAVariable(self.fuel_var) and synchronizes it withVMStoreContext::fuel_consumedacross calls, returns, and exception handlers.Previously, stack-switching instructions (
resume,resume_throw,resume_throw_ref,suspend, andswitch) did not flush/saveself.fuel_varbefore switching stacks or reloadself.fuel_varupon returning or resuming, andtranslate_resume_impldid not reloadself.fuel_varat the entry ofsuspend_blockbefore dispatching to(on $tag $label)handler blocks. As a result, fuel consumed inside a continuation was overwritten whenever control switched back to the parent or target stack.Save
self.fuel_varinfuel_before_opprior toresume*,suspend, andswitch, reloadself.fuel_varinfuel_after_opon normal return/wake-up, and callenv.on_catch_block_entry(builder)at the start ofsuspend_block.Assisted-by: Gemini