[debugger] infrastructure for side-effect-free debug-evaluate.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index b76d3357a32e9f4c2fc3750895f75471d3fd5909..322d7a081fe35ff477ee6fa57ce6b4c3d6eacd62 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -7375,6 +7375,9 @@ class SharedFunctionInfo: public HeapObject {
   // The function's name if it is non-empty, otherwise the inferred name.
   String* DebugName();
 
+  // The function cannot cause any side effects.
+  bool HasNoSideEffect();
+
   // Used for flags such as --hydrogen-filter.
   bool PassesFilter(const char* raw_filter);
 
@@ -7484,6 +7487,12 @@ class SharedFunctionInfo: public HeapObject {
   // Indicates that asm->wasm conversion failed and should not be re-attempted.
   DECL_BOOLEAN_ACCESSORS(is_asm_wasm_broken)
 
+  // Indicates that the function cannot cause side-effects.
+  DECL_BOOLEAN_ACCESSORS(has_no_side_effect)
+
+  // Indicates that |has_no_side_effect| has been computed and set.
+  DECL_BOOLEAN_ACCESSORS(computed_has_no_side_effect)
+
   inline FunctionKind kind() const;
   inline void set_kind(FunctionKind kind);
 
@@ -7770,6 +7779,8 @@ class SharedFunctionInfo: public HeapObject {
     // byte 3
     kDeserialized = kFunctionKind + 10,
     kIsAsmWasmBroken,
+    kHasNoSideEffect,
+    kComputedHasNoSideEffect,
     kCompilerHintsCount,  // Pseudo entry
   };
   // kFunctionKind has to be byte-aligned