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Jakob Gruber authored
This is a reland of 1e472c42 No change, this was a speculative revert to unblock the roll. TBR=jgruber Original change's description: > [compiler] Track the maximal unoptimized frame size > > This is another step towards considering the unoptimized frame size in > stack checks within optimized code. > > With the changes in this CL, we now keep track of the maximal > unoptimized frame size of the function that is currently being > compiled. An optimized function may inline multiple unoptimized > functions, so a single optimized frame can deopt to multiple > frames. The real frame size thus differs in different parts of the > optimized function. > > We only care about the maximal frame size, which we calculate > conservatively as an over-approximation, and track in > InstructionSelector::max_unoptimized_frame_height_ for now. In future > work, this value will be passed on to codegen, where it will be > applied as an offset to the stack pointer during the stack check. > > (The motivation behind this is to avoid stack overflows through deopts, > caused by size differences between optimized and unoptimized frames.) > > Note that this offset only ensure that the topmost optimized frame can > deopt without overflowing the stack limit. That's fine, because we only > deopt optimized frames one at a time. Other (non-topmost) frames are > only deoptimized once they are returned to. > > Drive-by: Print variable and total frame height in --trace-deopt. > > Bug: v8:9534 > Change-Id: I821684a9da93bff59c20c8ab226105e7e12d93eb > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1762024 > Commit-Queue: Jakob Gruber <jgruber@chromium.org> > Auto-Submit: Jakob Gruber <jgruber@chromium.org> > Reviewed-by: Sigurd Schneider <sigurds@chromium.org> > Reviewed-by: Georg Neis <neis@chromium.org> > Cr-Commit-Position: refs/heads/master@{#63330} Bug: v8:9534 Change-Id: I686f200e7be1f419e23e50789e11607a0b2886d9 Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1766645 Commit-Queue: Bill Budge <bbudge@chromium.org> Reviewed-by: Bill Budge <bbudge@chromium.org> Cr-Commit-Position: refs/heads/master@{#63356}
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