diff --git a/src/compiler/iroptimizer.js b/src/compiler/iroptimizer.js
index ae7d98e495..2693613425 100644
--- a/src/compiler/iroptimizer.js
+++ b/src/compiler/iroptimizer.js
@@ -559,9 +559,12 @@ class IROptimizer {
             break;
         case StackOpcode.CONTROL_WHILE:
         case StackOpcode.CONTROL_FOR:
+            modified = this.analyzeInputs(inputs, state) || modified;
+            modified = this.analyzeLoopedStack(inputs.do, state, stackBlock, true) || modified;
+            break;
         case StackOpcode.CONTROL_REPEAT:
             modified = this.analyzeInputs(inputs, state) || modified;
-            modified = this.analyzeLoopedStack(inputs.do, state, stackBlock) || modified;
+            modified = this.analyzeLoopedStack(inputs.do, state, stackBlock, false) || modified;
             break;
         case StackOpcode.CONTROL_IF_ELSE: {
             modified = this.analyzeInputs(inputs, state) || modified;
@@ -642,20 +645,24 @@ class IROptimizer {
      * @param {IntermediateStack} stack
      * @param {TypeState} state
      * @param {IntermediateStackBlock} block
+     * @param {boolean} willReevaluateInputs
      * @returns {boolean}
      * @private
      */
-    analyzeLoopedStack (stack, state, block) {
+    analyzeLoopedStack (stack, state, block, willReevaluateInputs) {
+        let modified = false;
+
         if (block.yields && !this.ignoreYields) {
-            let modified = state.clear();
+            modified = state.clear();
+            if (willReevaluateInputs) {
+                modified = this.analyzeInputs(block.inputs, state) || modified;
+            }
             block.entryState = state.clone();
             block.exitState = state.clone();
-            modified = this.analyzeInputs(block.inputs, state) || modified;
             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.
@@ -672,7 +679,10 @@ class IROptimizer {
             const newState = state.clone();
             modified = this.analyzeStack(stack, newState) || modified;
             modified = (keepLooping = state.or(newState)) || modified;
-            modified = this.analyzeInputs(block.inputs, state) || modified;
+
+            if (willReevaluateInputs) {
+                modified = this.analyzeInputs(block.inputs, state) || modified;
+            }
         } while (keepLooping);
         block.entryState = state.clone();
         return modified;
diff --git a/test/fixtures/execute/tw-repeat-analysis-doesnt-reanalyze.sb3 b/test/fixtures/execute/tw-repeat-analysis-doesnt-reanalyze.sb3
new file mode 100644
index 0000000000..12d51fb79b
Binary files /dev/null and b/test/fixtures/execute/tw-repeat-analysis-doesnt-reanalyze.sb3 differ
diff --git a/test/snapshot/__snapshots__/tw-repeat-analysis-doesnt-reanalyze.sb3.tw-snapshot b/test/snapshot/__snapshots__/tw-repeat-analysis-doesnt-reanalyze.sb3.tw-snapshot
new file mode 100644
index 0000000000..020097c50f
--- /dev/null
+++ b/test/snapshot/__snapshots__/tw-repeat-analysis-doesnt-reanalyze.sb3.tw-snapshot
@@ -0,0 +1,28 @@
+// TW Snapshot
+// Input SHA-256: 38075839898d1ba3d2556f350ff18438a205c5b6b3cb809d07d3f738bd37dad9
+
+// Sprite1 script
+(function factoryXYZ(thread) { const target = thread.target; const runtime = target.runtime; const stage = runtime.getTargetForStage();
+const b0 = runtime.getOpcodeFunction("looks_say");
+const b1 = stage.variables["`jEk@4|i[#Fk?(8x)AV.-my variable"];
+return function* genXYZ () {
+yield* executeInCompatibilityLayer({"MESSAGE":"plan 1",}, b0, false, false, "d", null);
+thread.procedures["Wa"]();
+if ((("" + b1.value).toLowerCase() === "bwah".toLowerCase())) {
+yield* executeInCompatibilityLayer({"MESSAGE":"pass",}, b0, false, false, "l", null);
+}
+yield* executeInCompatibilityLayer({"MESSAGE":"end",}, b0, false, false, "k", null);
+retire(); return;
+}; })
+
+// Sprite1 Wa
+(function factoryXYZ(thread) { const target = thread.target; const runtime = target.runtime; const stage = runtime.getTargetForStage();
+const b0 = stage.variables["`jEk@4|i[#Fk?(8x)AV.-my variable"];
+const b1 = stage.variables["6h7bpiz0`;;x^G1B3(%["];
+return function funXYZ_a () {
+b0.value = b1.value.length;
+for (var a0 = b0.value; a0 > 0; a0--) {
+b0.value = "bwah";
+}
+return "";
+}; })
diff --git a/test/snapshot/__snapshots__/warp-timer/tw-repeat-analysis-doesnt-reanalyze.sb3.tw-snapshot b/test/snapshot/__snapshots__/warp-timer/tw-repeat-analysis-doesnt-reanalyze.sb3.tw-snapshot
new file mode 100644
index 0000000000..35a0f59d7b
--- /dev/null
+++ b/test/snapshot/__snapshots__/warp-timer/tw-repeat-analysis-doesnt-reanalyze.sb3.tw-snapshot
@@ -0,0 +1,29 @@
+// TW Snapshot
+// Input SHA-256: 38075839898d1ba3d2556f350ff18438a205c5b6b3cb809d07d3f738bd37dad9
+
+// Sprite1 script
+(function factoryXYZ(thread) { const target = thread.target; const runtime = target.runtime; const stage = runtime.getTargetForStage();
+const b0 = runtime.getOpcodeFunction("looks_say");
+const b1 = stage.variables["`jEk@4|i[#Fk?(8x)AV.-my variable"];
+return function* genXYZ () {
+yield* executeInCompatibilityLayer({"MESSAGE":"plan 1",}, b0, false, false, "d", null);
+yield* thread.procedures["Wa"]();
+if ((("" + b1.value).toLowerCase() === "bwah".toLowerCase())) {
+yield* executeInCompatibilityLayer({"MESSAGE":"pass",}, b0, false, false, "l", null);
+}
+yield* executeInCompatibilityLayer({"MESSAGE":"end",}, b0, false, false, "k", null);
+retire(); return;
+}; })
+
+// Sprite1 Wa
+(function factoryXYZ(thread) { const target = thread.target; const runtime = target.runtime; const stage = runtime.getTargetForStage();
+const b0 = stage.variables["`jEk@4|i[#Fk?(8x)AV.-my variable"];
+const b1 = stage.variables["6h7bpiz0`;;x^G1B3(%["];
+return function* genXYZ_a () {
+b0.value = b1.value.length;
+for (var a0 = b0.value; a0 > 0; a0--) {
+b0.value = "bwah";
+if (isStuck()) yield;
+}
+return "";
+}; })