diff --git a/include/jemalloc/internal/rtree_inlines.h b/include/jemalloc/internal/rtree_inlines.h
index 4b848541..0d96948b 100644
--- a/include/jemalloc/internal/rtree_inlines.h
+++ b/include/jemalloc/internal/rtree_inlines.h
@@ -79,43 +79,41 @@ rtree_elm_write(rtree_elm_t *elm, const extent_t *extent) {
 JEMALLOC_ALWAYS_INLINE rtree_elm_t *
 rtree_elm_lookup(tsdn_t *tsdn, rtree_t *rtree, rtree_ctx_t *rtree_ctx,
     uintptr_t key, bool dependent, bool init_missing) {
+	assert(key != 0);
 	assert(!dependent || !init_missing);
 
-	if (likely(key != 0)) {
-		uintptr_t leafkey = rtree_leafkey(key);
+	uintptr_t leafkey = rtree_leafkey(key);
 #define RTREE_CACHE_CHECK(i) do {					\
-		if (likely(rtree_ctx->cache[i].leafkey == leafkey)) {	\
-			rtree_elm_t *leaf = rtree_ctx->cache[i].leaf;	\
-			if (likely(leaf != NULL)) {			\
-				/* Reorder. */				\
-				memmove(&rtree_ctx->cache[1],		\
-				    &rtree_ctx->cache[0],		\
-				    sizeof(rtree_ctx_cache_elm_t) * i);	\
-				rtree_ctx->cache[0].leafkey = leafkey;	\
-				rtree_ctx->cache[0].leaf = leaf;	\
+	if (likely(rtree_ctx->cache[i].leafkey == leafkey)) {		\
+		rtree_elm_t *leaf = rtree_ctx->cache[i].leaf;		\
+		if (likely(leaf != NULL)) {				\
+			/* Reorder. */					\
+			memmove(&rtree_ctx->cache[1],			\
+			    &rtree_ctx->cache[0],			\
+			    sizeof(rtree_ctx_cache_elm_t) * i);		\
+			rtree_ctx->cache[0].leafkey = leafkey;		\
+			rtree_ctx->cache[0].leaf = leaf;		\
 									\
-				uintptr_t subkey = rtree_subkey(key,	\
-				    RTREE_HEIGHT-1);			\
-				return &leaf[subkey];			\
-			}						\
+			uintptr_t subkey = rtree_subkey(key,		\
+			    RTREE_HEIGHT-1);				\
+			return &leaf[subkey];				\
 		}							\
+	}								\
 } while (0)
-		/* Check the MRU cache entry. */
-		RTREE_CACHE_CHECK(0);
-		/*
-		 * Search the remaining cache elements, and on success move the
-		 * matching element to the front.  Unroll the first iteration to
-		 * avoid calling memmove() (the compiler typically optimizes it
-		 * into raw moves).
-		 */
-		if (RTREE_CTX_NCACHE > 1) {
-			RTREE_CACHE_CHECK(1);
-		}
-		for (unsigned i = 2; i < RTREE_CTX_NCACHE; i++) {
-			RTREE_CACHE_CHECK(i);
-		}
-#undef RTREE_CACHE_CHECK
+	/* Check the MRU cache entry. */
+	RTREE_CACHE_CHECK(0);
+	/*
+	 * Search the remaining cache elements, and on success move the matching
+	 * element to the front.  Unroll the first iteration to avoid calling
+	 * memmove() (the compiler typically optimizes it into raw moves).
+	 */
+	if (RTREE_CTX_NCACHE > 1) {
+		RTREE_CACHE_CHECK(1);
 	}
+	for (unsigned i = 2; i < RTREE_CTX_NCACHE; i++) {
+		RTREE_CACHE_CHECK(i);
+	}
+#undef RTREE_CACHE_CHECK
 
 	return rtree_elm_lookup_hard(tsdn, rtree, rtree_ctx, key, dependent,
 	    init_missing);
diff --git a/src/rtree.c b/src/rtree.c
index 83929ba6..a86fa45d 100644
--- a/src/rtree.c
+++ b/src/rtree.c
@@ -170,17 +170,15 @@ rtree_elm_lookup_hard(tsdn_t *tsdn, rtree_t *rtree, rtree_ctx_t *rtree_ctx,
 		 * node is a leaf, so it contains values rather than	\
 		 * child pointers.					\
 		 */							\
-		if (likely(key != 0)) {					\
-			if (RTREE_CTX_NCACHE > 1) {			\
-				memmove(&rtree_ctx->cache[1],		\
-				    &rtree_ctx->cache[0],		\
-				    sizeof(rtree_ctx_cache_elm_t) *	\
-				    (RTREE_CTX_NCACHE-1));		\
-			}						\
-			uintptr_t leafkey = rtree_leafkey(key);		\
-			rtree_ctx->cache[0].leafkey = leafkey;		\
-			rtree_ctx->cache[0].leaf = node;		\
+		if (RTREE_CTX_NCACHE > 1) {				\
+			memmove(&rtree_ctx->cache[1],			\
+			    &rtree_ctx->cache[0],			\
+			    sizeof(rtree_ctx_cache_elm_t) *		\
+			    (RTREE_CTX_NCACHE-1));			\
 		}							\
+		uintptr_t leafkey = rtree_leafkey(key);			\
+		rtree_ctx->cache[0].leafkey = leafkey;			\
+		rtree_ctx->cache[0].leaf = node;			\
 		uintptr_t subkey = rtree_subkey(key, level);		\
 		return &node[subkey];					\
 	}
diff --git a/test/unit/rtree.c b/test/unit/rtree.c
index 2088595b..488fd54b 100644
--- a/test/unit/rtree.c
+++ b/test/unit/rtree.c
@@ -40,7 +40,7 @@ TEST_BEGIN(test_rtree_read_empty) {
 	rtree_ctx_t rtree_ctx = RTREE_CTX_INITIALIZER;
 	test_rtree = &rtree;
 	assert_false(rtree_new(&rtree), "Unexpected rtree_new() failure");
-	assert_ptr_null(rtree_read(tsdn, &rtree, &rtree_ctx, 0, false),
+	assert_ptr_null(rtree_read(tsdn, &rtree, &rtree_ctx, PAGE, false),
 	    "rtree_read() should return NULL for empty tree");
 	rtree_delete(tsdn, &rtree);
 	test_rtree = NULL;
@@ -139,9 +139,10 @@ TEST_BEGIN(test_rtree_extrema) {
 	test_rtree = &rtree;
 	assert_false(rtree_new(&rtree), "Unexpected rtree_new() failure");
 
-	assert_false(rtree_write(tsdn, &rtree, &rtree_ctx, 0, &extent_a),
+	assert_false(rtree_write(tsdn, &rtree, &rtree_ctx, PAGE, &extent_a),
 	    "Unexpected rtree_write() failure");
-	assert_ptr_eq(rtree_read(tsdn, &rtree, &rtree_ctx, 0, true), &extent_a,
+	assert_ptr_eq(rtree_read(tsdn, &rtree, &rtree_ctx, PAGE, true),
+	    &extent_a,
 	    "rtree_read() should return previously set value");
 
 	assert_false(rtree_write(tsdn, &rtree, &rtree_ctx, ~((uintptr_t)0),
@@ -158,7 +159,8 @@ TEST_END
 TEST_BEGIN(test_rtree_bits) {
 	tsdn_t *tsdn = tsdn_fetch();
 
-	uintptr_t keys[] = {0, 1, (((uintptr_t)1) << LG_PAGE) - 1};
+	uintptr_t keys[] = {PAGE, PAGE + 1,
+	    PAGE + (((uintptr_t)1) << LG_PAGE) - 1};
 
 	extent_t extent;
 	rtree_t rtree;
@@ -180,7 +182,7 @@ TEST_BEGIN(test_rtree_bits) {
 			    "key=%#"FMTxPTR, i, j, keys[i], keys[j]);
 		}
 		assert_ptr_null(rtree_read(tsdn, &rtree, &rtree_ctx,
-		    (((uintptr_t)1) << LG_PAGE), false),
+		    (((uintptr_t)2) << LG_PAGE), false),
 		    "Only leftmost rtree leaf should be set; i=%u", i);
 		rtree_clear(tsdn, &rtree, &rtree_ctx, keys[i]);
 	}