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ishell@chromium.org authored
... - a code range size agnostic version of InterpreterEntryTrampoline builtin. The new builtin is fully compatible with the default version and used as a template for creating interpreter entry trampoline Code objects when --interpreted-frames-native-stack is enabled. This CL introduces a new assembler option "position_independent_code" which affects the way builtin calls are generated. This mode is enabled only for InterpreterEntryTrampolineForProfiling. Motivation: * InterpreterEntryTrampoline uses RelocInfo::CODE_TARGET for calling other builtins which requires the code range to be small enough to allow PC-relative jumps/calls between Code objects. This is the reason why --interpreted-frames-native-stack was not supported on arm and might not work on arm64 because the code range is bigger than the max PC-relative distance for call/jump instructions. The new builtin calls other builtins via builtins entry table which makes the code fully relocatable and usable for any code range size. * RelocInfo::CODE_TARGET requires a target code to be materialized as a Code object which contradicts the Code-less builtins goal. * The --interpreted-frames-native-stack is rarely used in the wild but we have to pay the price of deserializing InterpreterEntryTrampoline builtin as a Code object which consumes address space in the code range and thus limits the number of V8 isolates that can be created because of code range exhaustion. Now the pointer compression cage becomes the limiting factor instead of the code range. * We can remove complicated logic of Factory::CopyCode() and respective support on GC side. Bug: v8:11880, v8:8713, v8:12592 Change-Id: Ib72e28c03496c43db42f6fe46622def12e102f31 Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3811287Reviewed-by: Jakob Linke <jgruber@chromium.org> Commit-Queue: Igor Sheludko <ishell@chromium.org> Reviewed-by: Dominik Inführ <dinfuehr@chromium.org> Cr-Commit-Position: refs/heads/main@{#82263}
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