[LLDB] Allow expression evaluators to set arbitrary timeouts

llvm@59237bb changed the behavior of the `SetTimeout` and `GetTimeout` methods of `EvaluateExpressionOptions`, which broke the Mojo REPL and related services (https://docs.modular.com/mojo/) because it relies on having infinite timeouts. That's a necessity because developers often use the REPL for executing extremely long-running numeric jobs. Having said that, `EvaluateExpressionOptions` shouldn't be that opinionated on this matter anyway. Instead, it should be the responsibility of the evaluator to define which timeout to use for each specific case.

Differential Revision: https://reviews.llvm.org/D157764

Author: walter erquinigo

lldb/include/lldb/Target/Target.h

@@ -346,16 +346,9 @@ class EvaluateExpressionOptions {
     m_use_dynamic = dynamic;
   }
 
-  const Timeout<std::micro> &GetTimeout() const {
-    assert(m_timeout && m_timeout->count() > 0);
-    return m_timeout;
-  }
+  const Timeout<std::micro> &GetTimeout() const { return m_timeout; }
 
-  void SetTimeout(const Timeout<std::micro> &timeout) {
-    // Disallow setting a non-zero timeout.
-    if (timeout && timeout->count() > 0)
-      m_timeout = timeout;
-  }
+  void SetTimeout(const Timeout<std::micro> &timeout) { m_timeout = timeout; }
 
   const Timeout<std::micro> &GetOneThreadTimeout() const {
     return m_one_thread_timeout;

lldb/test/API/commands/expression/ir-interpreter/TestIRInterpreter.py

@@ -31,8 +31,8 @@ def test_interpreter_timeout(self):
         # This is an IRInterpreter specific test, so disable the JIT.
         options.SetAllowJIT(False)
 
-        # No timeout means a 500ms.
-        options.SetTimeoutInMicroSeconds(0)
+        # We use a 500ms timeout.
+        options.SetTimeoutInMicroSeconds(500000)
         res, duration_sec = self.time_expression(inf_loop, options)
         self.assertIn(timeout_error, str(res.GetError()))