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-rw-r--r--deps/v8/src/compiler/frame-elider.cc35
1 files changed, 29 insertions, 6 deletions
diff --git a/deps/v8/src/compiler/frame-elider.cc b/deps/v8/src/compiler/frame-elider.cc
index bb17d1215f..dd8db83dd5 100644
--- a/deps/v8/src/compiler/frame-elider.cc
+++ b/deps/v8/src/compiler/frame-elider.cc
@@ -114,13 +114,36 @@ bool FrameElider::PropagateIntoBlock(InstructionBlock* block) {
}
}
- // Propagate towards start ("upwards") if there are successors and all of
- // them need a frame.
- for (RpoNumber& succ : block->successors()) {
- if (!InstructionBlockAt(succ)->needs_frame()) return false;
+ // Propagate towards start ("upwards")
+ bool need_frame_successors = false;
+ if (block->SuccessorCount() == 1) {
+ // For single successors, propagate the needs_frame information.
+ need_frame_successors =
+ InstructionBlockAt(block->successors()[0])->needs_frame();
+ } else {
+ // For multiple successors, each successor must only have a single
+ // predecessor (because the graph is in edge-split form), so each successor
+ // can independently create/dismantle a frame if needed. Given this
+ // independent control, only propagate needs_frame if all non-deferred
+ // blocks need a frame.
+ for (RpoNumber& succ : block->successors()) {
+ InstructionBlock* successor_block = InstructionBlockAt(succ);
+ DCHECK_EQ(1, successor_block->PredecessorCount());
+ if (!successor_block->IsDeferred()) {
+ if (successor_block->needs_frame()) {
+ need_frame_successors = true;
+ } else {
+ return false;
+ }
+ }
+ }
+ }
+ if (need_frame_successors) {
+ block->mark_needs_frame();
+ return true;
+ } else {
+ return false;
}
- block->mark_needs_frame();
- return true;
}