From 7994e7030976f9fcd321a4d1d5f76f4582e01905 Mon Sep 17 00:00:00 2001
From: Andrew Adams <andrew.b.adams@gmail.com>
Date: Tue, 16 Apr 2024 14:27:43 -0700
Subject: [PATCH] Fix corner case in if_then_else simplification (#8189)

Co-authored-by: Steven Johnson <srj@google.com>
---
 src/Simplify_Call.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/Simplify_Call.cpp b/src/Simplify_Call.cpp
index 33d11ccb8d06..29bc75aa2bb2 100644
--- a/src/Simplify_Call.cpp
+++ b/src/Simplify_Call.cpp
@@ -576,7 +576,11 @@ Expr Simplify::visit(const Call *op, ExprInfo *bounds) {
             }
             in_unreachable = false;
             if (true_unreachable) {
-                return false_value;
+                if (false_value.defined()) {
+                    return false_value;
+                } else {
+                    return make_zero(op->type);
+                }
             } else if (false_unreachable) {
                 return true_value;
             }