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Paolo Severini authored
This is a reland of 3cda21de Original change's description: > V8 x64 backend doesn't emit ABI compliant stack frames > > On 64 bit Windows, the OS stack walking does not work because the V8 x64 > backend doesn't emit unwinding info and also because it doesn't emit ABI > compliant stack frames. See > https://docs.google.com/document/d/1-wf50jFlii0c_Pr52lm2ZU-49m220nhYMrHDi3vXnh0/edit > for more details. > > This problem can be fixed by observing that V8 frames usually all have the same > prolog and epilog: > > push rbp, > mov rbp, rsp > ... > pop rbp > ret N > > and that it is possible to define XDATA (UNWIND_CODEs) that specify how Windows > should walk through V8 frames. Furthermore, since V8 Code objects are all > allocated in the same code-range for an Isolate, it is possible to register a > single PDATA/XDATA entry to cover stack walking for all the code generated > inside that code-range. > > This PR contains changes required to enable stack walking on Win64: > > EmbeddedFileWriter now adds assembler directives to the builtins > snapshot source file (embedded.cc) to emit additional entries in the .pdata and > in the .xdata section of the V8 executable. This takes care of stack walking > for embedded builtins. (The case of non-embedded builtins is not supported). > The x64 Assembler has been modified to collect the information required to emit > this unwind info for builtins. > > Stack walking for jitted code is handled is Isolate.cpp, by registering > dynamically PDATA/XDATA for the whole code-range address space every time a new > Isolate is initialized, and by unregistering them when the Isolate is > destroyed. > > Stack walking for WASM jitted code is handled is the same way in > wasm::NativeModule (wasm/wasm-code-manager.cpp). > > It is important to note that Crashpad and Breakpad are already registering > PDATA/XDATA to manage and report unhandled exceptions (but not for embedded > builtins). Since it is not possible to register multiple PDATA entries for the > same address range, a new function is added to the V8 API: > SetUnhandledExceptionCallback() can be used by an embedder to register its own > unhandled exception handler for exceptions that arise in v8-generated code. > V8 embedders should be modified accordingly (code for this is in a separate PR > in the Chromium repository: > https://chromium-review.googlesource.com/c/chromium/src/+/1474703). > > All these changes are experimental, behind: > > the 'v8_win64_unwinding_info' build flag, and > the '--win64-unwinding-info' runtime flag. > > Bug: v8:3598 > Change-Id: Iea455ab6d0e2bf1c556aa1cf870841d44ab6e4b1 > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1469329 > Reviewed-by: Michael Starzinger <mstarzinger@chromium.org> > Reviewed-by: Jakob Gruber <jgruber@chromium.org> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org> > Commit-Queue: Paolo Severini <paolosev@microsoft.com> > Cr-Commit-Position: refs/heads/master@{#60330} Bug: v8:3598 Change-Id: If988baf7d3e4af165b919d6e54c1ad985f8e25e3 Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1534618Reviewed-by: Jakob Gruber <jgruber@chromium.org> Reviewed-by: Ulan Degenbaev <ulan@chromium.org> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org> Commit-Queue: Paolo Severini <paolosev@microsoft.com> Cr-Commit-Position: refs/heads/master@{#60581}
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