Keep track of stack usage, report line that used the most

This won't keep track of everything, but was useful in tracking down
some recursive variables in the android build that shouldn't have been
recursive (they were using 1MB+ of stack).

Change-Id: I5e6b70480cffbebb09dfd72276017559480da948

1 files changed, 7 insertions, 1 deletions

diff --git a/expr.cc b/expr.cc
index f0afb7b..5419900 100644
--- a/expr.cc
+++ b/expr.cc
@@ -52,7 +52,8 @@ class Literal : public Value {
 
   StringPiece val() const { return s_; }
 
-  virtual void Eval(Evaluator*, string* s) const override {
+  virtual void Eval(Evaluator* ev, string* s) const override {
+    ev->CheckStack();
     s->append(s_.begin(), s_.end());
   }
 
@@ -79,6 +80,7 @@ class Expr : public Value {
   void AddValue(Value* v) { vals_.push_back(v); }
 
   virtual void Eval(Evaluator* ev, string* s) const override {
+    ev->CheckStack();
     for (Value* v : vals_) {
       v->Eval(ev, s);
     }
@@ -119,6 +121,7 @@ class SymRef : public Value {
   virtual ~SymRef() {}
 
   virtual void Eval(Evaluator* ev, string* s) const override {
+    ev->CheckStack();
     Var* v = ev->LookupVar(name_);
     v->Used(ev, name_);
     v->Eval(ev, s);
@@ -138,6 +141,7 @@ class VarRef : public Value {
   virtual ~VarRef() { delete name_; }
 
   virtual void Eval(Evaluator* ev, string* s) const override {
+    ev->CheckStack();
     ev->IncrementEvalDepth();
     const string&& name = name_->Eval(ev);
     ev->DecrementEvalDepth();
@@ -166,6 +170,7 @@ class VarSubst : public Value {
   }
 
   virtual void Eval(Evaluator* ev, string* s) const override {
+    ev->CheckStack();
     ev->IncrementEvalDepth();
     const string&& name = name_->Eval(ev);
     Symbol sym = Intern(name);
@@ -205,6 +210,7 @@ class Func : public Value {
   }
 
   virtual void Eval(Evaluator* ev, string* s) const override {
+    ev->CheckStack();
     LOG("Invoke func %s(%s)", name(), JoinValues(args_, ",").c_str());
     ev->IncrementEvalDepth();
     fi_->func(args_, ev, s);