Give up analyzing looped stack after 10000 iterations

Temporary fix for an infinite loop, to be properly fixed later

Author: GarboMuffin

src/compiler/iroptimizer.js

@@ -627,9 +627,21 @@ class IROptimizer {
             return this.analyzeStack(stack, state) || modified;
         }
 
+        let iterations = 0;
         let modified = false;
         let keepLooping;
         do {
+            // If we are stuck in an apparent infinite loop, give up and assume the worst.
+            if (iterations > 10000) {
+                console.error('analyzeLoopedStack stuck in likely infinite loop; quitting', block, state);
+                modified = state.clear();
+                block.entryState = state.clone();
+                block.exitState = state.clone();
+                modified = this.analyzeInputs(block.inputs, state) || modified;
+                return this.analyzeStack(stack, state) || modified;
+            }
+            iterations++;
+
             const newState = state.clone();
             modified = this.analyzeStack(stack, newState) || modified;
             modified = (keepLooping = state.or(newState)) || modified;

test/fixtures/execute/tw-repeat-procedure-reporter-infinite-analyzer-loop.sb3

@@ -0,0 +1,29 @@
+// TW Snapshot
+// Input SHA-256: a12680688ca945364abe1e094b35cf53326f70189cb09b58d5f52b4de0c3b2a9
+
+// Text script
+(function factoryXYZ(thread) { const target = thread.target; const runtime = target.runtime; const stage = runtime.getTargetForStage();
+const b0 = runtime.getOpcodeFunction("looks_say");
+return function* genXYZ () {
+yield* executeInCompatibilityLayer({"MESSAGE":"plan 0",}, b0, false, false, "a~", null);
+thread.procedures["Wtest 1"]();
+yield* executeInCompatibilityLayer({"MESSAGE":"end",}, b0, false, false, "dh", null);
+retire(); return;
+}; })
+
+// Text Wtest 1
+(function factoryXYZ(thread) { const target = thread.target; const runtime = target.runtime; const stage = runtime.getTargetForStage();
+const b0 = target.variables["ts-.PQ{/]mN_9@MbG:m/"];
+return function funXYZ_test_1 () {
+for (var a0 = (+thread.procedures["Wany procedure reporter"]() || 0); a0 >= 0.5; a0--) {
+b0.value = ((+b0.value || 0) + 1);
+}
+return "";
+}; })
+
+// Text Wany procedure reporter
+(function factoryXYZ(thread) { const target = thread.target; const runtime = target.runtime; const stage = runtime.getTargetForStage();
+return function funXYZ_any_procedure_report () {
+return 0;
+return "";
+}; })

test/snapshot/__snapshots__/tw-repeat-procedure-reporter-infinite-analyzer-loop.sb3.tw-snapshot

@@ -0,0 +1,30 @@
+// TW Snapshot
+// Input SHA-256: a12680688ca945364abe1e094b35cf53326f70189cb09b58d5f52b4de0c3b2a9
+
+// Text script
+(function factoryXYZ(thread) { const target = thread.target; const runtime = target.runtime; const stage = runtime.getTargetForStage();
+const b0 = runtime.getOpcodeFunction("looks_say");
+return function* genXYZ () {
+yield* executeInCompatibilityLayer({"MESSAGE":"plan 0",}, b0, false, false, "a~", null);
+yield* thread.procedures["Wtest 1"]();
+yield* executeInCompatibilityLayer({"MESSAGE":"end",}, b0, false, false, "dh", null);
+retire(); return;
+}; })
+
+// Text Wtest 1
+(function factoryXYZ(thread) { const target = thread.target; const runtime = target.runtime; const stage = runtime.getTargetForStage();
+const b0 = target.variables["ts-.PQ{/]mN_9@MbG:m/"];
+return function* genXYZ_test_1 () {
+for (var a0 = (+thread.procedures["Wany procedure reporter"]() || 0); a0 >= 0.5; a0--) {
+b0.value = ((+b0.value || 0) + 1);
+if (isStuck()) yield;
+}
+return "";
+}; })
+
+// Text Wany procedure reporter
+(function factoryXYZ(thread) { const target = thread.target; const runtime = target.runtime; const stage = runtime.getTargetForStage();
+return function funXYZ_any_procedure_report () {
+return 0;
+return "";
+}; })