commit | 8bdae002f165883312a82b7549517930bfa6fe75 | [log] [tgz] |
---|---|---|
author | Vyacheslav Egorov <vegorov@google.com> | Wed Nov 10 17:52:03 2021 +0000 |
committer | commit-bot@chromium.org <commit-bot@chromium.org> | Wed Nov 10 17:52:03 2021 +0000 |
tree | 2ab3022b895be8ed877ede1bcd2ea03ec0ec662e | |
parent | c6fe2b6f6a39ca3865559f6c88dbadeb62410896 [diff] |
[vm] Fix symbolization of future listener frame. For future listener frames async unwinding produces frames with `pc_offset` set to 0, because this frames correspond to closures which will be invoked once the future completes. Such frames are different from most other frames which correspond to real call or yield locations within native code and have non-zero `pc_offset`. Because there is no call-/yield- site at 0 compiler does not emit any source location information into CodeSourceMap and consequently runtime can't produce much beyond file name in the stack trace for these special frames. To make matters worse ordering of code objects in the AOT snapshot could affect symbolization of such frames - sometimes resulting in an arbitrary token position being attached to the symbolized frame. This CL adds more special handling of these frames into StackTrace::ToCString and changes compiler to emit a dummy source position descriptor for the start of every closure function. This descriptor is encoded as ChangePosition function.token_pos() AdvancePC 0 in the CodeSourceMap. This entry is then handled specially when generating DWARF. This is reland of https://dart-review.googlesource.com/c/sdk/+/219781 with fixes for ARM build. TEST=vm/dart{,_2}/causal_stacks/async_throws_stack_lazy{,_lazy_non_symbolic}_test Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-product-x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-dwarf-linux-product-x64-try Change-Id: I06f80c1125422675758917ea12cdf2c70a2f6deb Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/219795 Auto-Submit: Slava Egorov <vegorov@google.com> Commit-Queue: Slava Egorov <vegorov@google.com> Commit-Queue: Alexander Aprelev <aam@google.com> Reviewed-by: Alexander Aprelev <aam@google.com>
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