MIPS: [turbofan] Make sure binop results do not overwrite deoptimization inputs on arm.

src/compiler/mips/instruction-selector-mips.cc

Index: src/compiler/mips/instruction-selector-mips.cc
diff --git a/src/compiler/mips/instruction-selector-mips.cc b/src/compiler/mips/instruction-selector-mips.cc
index c95613eba8b058b14aef800575db748cbe8528e5..615d9d9018a99466326c289a188e7c7630750e3f 100644
--- a/src/compiler/mips/instruction-selector-mips.cc
+++ b/src/compiler/mips/instruction-selector-mips.cc
@@ -104,7 +104,14 @@ static void VisitBinop(InstructionSelector* selector, Node* node,
     inputs[input_count++] = g.Label(cont->false_block());
   }
 
-  outputs[output_count++] = g.DefineAsRegister(node);
+  if (cont->IsDeoptimize()) {
+    // If we can deoptimize as a result of the binop, we need to make sure that
+    // the deopt inputs are not overwritten by the binop result. One way
+    // to achieve that is to declare the output register as same-as-first.
+    outputs[output_count++] = g.DefineSameAsFirst(node);
+  } else {
+    outputs[output_count++] = g.DefineAsRegister(node);
+  }
   if (cont->IsSet()) {
     outputs[output_count++] = g.DefineAsRegister(cont->result());
   }