From f3253ce50bcb201c2569fe1fd5ee670aab375205 Mon Sep 17 00:00:00 2001
From: Khouri Giordano <kgiordano@nikon.net>
Date: Wed, 12 Jul 2017 11:26:18 -0400
Subject: [PATCH] fix bound type mismatch for compares and document other
 fallthrough cases

---
 src/Bounds.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/Bounds.cpp b/src/Bounds.cpp
index 18358caa5883..31a63522d3bc 100644
--- a/src/Bounds.cpp
+++ b/src/Bounds.cpp
@@ -435,6 +435,7 @@ class Bounds : public IRVisitor {
 
         op->b.accept(this);
         if (!interval.is_bounded()) {
+            // Uses interval produced by op->b which might be half bound.
             return;
         }
         Interval b = interval;
@@ -503,12 +504,14 @@ class Bounds : public IRVisitor {
     void visit_compare(const Expr &a_expr, const Expr &b_expr) {
         a_expr.accept(this);
         if (!interval.is_bounded()) {
+            bounds_of_type(Bool());
             return;
         }
         Interval a = interval;
 
         b_expr.accept(this);
         if (!interval.is_bounded()) {
+            bounds_of_type(Bool());
             return;
         }
         Interval b = interval;
@@ -520,7 +523,7 @@ class Bounds : public IRVisitor {
         } else if (can_prove(always_false)) {
             interval = Interval::single_point(const_false());
         } else {
-            bounds_of_type(Bool(a_expr.type().lanes()));
+            bounds_of_type(Bool());
         }
     }
 
@@ -563,12 +566,14 @@ class Bounds : public IRVisitor {
     void visit(const Select *op) {
         op->true_value.accept(this);
         if (!interval.is_bounded()) {
+            // Uses interval produced by op->true_value which might be half bound.
             return;
         }
         Interval a = interval;
 
         op->false_value.accept(this);
         if (!interval.is_bounded()) {
+            // Uses interval produced by op->false_value which might be half bound.
             return;
         }
         Interval b = interval;