From 008b2fa47db4d04941a2bd6d512a204d76cbfea8 Mon Sep 17 00:00:00 2001
From: Julian Blake Kongslie
Date: Sun, 22 Jan 2023 12:33:01 -0800
Subject: Add deadman timer (only ten cycles!) based on time between
 interruptable points.

---
 Plan           | 1 -
 uarch/core.cpp | 3 +++
 uarch/core.h   | 2 ++
 3 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/Plan b/Plan
index 9e102f2..13f50b4 100644
--- a/Plan
+++ b/Plan
@@ -1,6 +1,5 @@
 vim: set sw=8 noet :
 
-	* Deadman timer
 	* D-side cache
 		* Store forwarding
 		* Cache consistency between I and D side
diff --git a/uarch/core.cpp b/uarch/core.cpp
index 503e286..ce58df2 100644
--- a/uarch/core.cpp
+++ b/uarch/core.cpp
@@ -364,6 +364,9 @@ bail_out:
         if (interrupt || oldctlregs != ctlregs)
             if (!restarttr.has_value())
                 restarttr = infra::pt::toplevel();
+        cycles_since_progress = 0;
+    } else {
+        assert(++cycles_since_progress < 10);
     }
 
     if (restarttr.has_value()) {
diff --git a/uarch/core.h b/uarch/core.h
index b8473e6..ebfd388 100644
--- a/uarch/core.h
+++ b/uarch/core.h
@@ -78,6 +78,8 @@ struct indir_stage : public infra::sim {
 struct exec_stage : public infra::sim {
     core &c;
 
+    unsigned int cycles_since_progress = 0;
+
     unsigned int gen = 0;
 
     unsigned int stores_sent = 0;
-- 
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