Eagerly allocate stack map spill slots when processing a block#13498
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In the safepoint spiller, eagerly allocate stack map spill slots when processing a block. This ensures that values that are live-out in the same block can never share a single stack map spill slot, which could otherwise happen with loop-invariant values that need inclusion in stack maps but which "don't" have an overlapping live range with a value defined inside the loop body if you only consider a single iteration (which is effectively what ignoring the live-out set accidentally did). Co-Authored-By: Jérôme Vouillon <jerome.vouillon@gmail.com>
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…odealliance#13498) * Eagerly allocate stack map spill slots when processing a block In the safepoint spiller, eagerly allocate stack map spill slots when processing a block. This ensures that values that are live-out in the same block can never share a single stack map spill slot, which could otherwise happen with loop-invariant values that need inclusion in stack maps but which "don't" have an overlapping live range with a value defined inside the loop body if you only consider a single iteration (which is effectively what ignoring the live-out set accidentally did). Co-Authored-By: Jérôme Vouillon <jerome.vouillon@gmail.com> * update disas test expectations * Only pre-allocate stack slots for values that are live across a safepoint --------- Co-authored-by: Jérôme Vouillon <jerome.vouillon@gmail.com>
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In the safepoint spiller, eagerly allocate stack map spill slots when processing a block. This ensures that values that are live-out in the same block can never share a single stack map spill slot, which could otherwise happen with loop-invariant values that need inclusion in stack maps but which "don't" have an overlapping live range with a value defined inside the loop body if you only consider a single iteration (which is effectively what ignoring the live-out set accidentally did).
Supersedes #13480
Fixes #13461