Reland "Propagating values from if clauses to its successors"

This reverts commit fa1034c563b44c4f557814c50e2678e14dcd1d13.

Reason for revert: Relanding after float/double fix. In short,
don't deal with floats/doubles since they bring a lot of edge cases e.g.

  if (f == 0.0f) {
    // f is not guaranteed to be 0.0f, e.g. it could be -0.0f.
  }

Bug: 240543764
Change-Id: I400bdab71dba0934e6f1740538fe6e6c0a7bf5fc

1 files changed, 9 insertions, 4 deletions

diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index 39cb9275fb..103d318710 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -2444,9 +2444,12 @@ class HInstruction : public ArenaObject<kArenaAllocInstruction> {
     return IsRemovable() && !HasUses();
   }
 
-  // Does this instruction strictly dominate `other_instruction`?
-  // Returns false if this instruction and `other_instruction` are the same.
-  // Aborts if this instruction and `other_instruction` are both phis.
+  // Does this instruction dominate `other_instruction`?
+  // Aborts if this instruction and `other_instruction` are different phis.
+  bool Dominates(HInstruction* other_instruction) const;
+
+  // Same but with `strictly dominates` i.e. returns false if this instruction and
+  // `other_instruction` are the same.
   bool StrictlyDominates(HInstruction* other_instruction) const;
 
   int GetId() const { return id_; }
@@ -2511,7 +2514,9 @@ class HInstruction : public ArenaObject<kArenaAllocInstruction> {
   void SetLocations(LocationSummary* locations) { locations_ = locations; }
 
   void ReplaceWith(HInstruction* instruction);
-  void ReplaceUsesDominatedBy(HInstruction* dominator, HInstruction* replacement);
+  void ReplaceUsesDominatedBy(HInstruction* dominator,
+                              HInstruction* replacement,
+                              bool strictly_dominated = true);
   void ReplaceEnvUsesDominatedBy(HInstruction* dominator, HInstruction* replacement);
   void ReplaceInput(HInstruction* replacement, size_t index);