Check non-zero in is_power_of_two()

And assert non-zero in floor_log2(). Fixes DASM_S_RANGE_I in ext/simplexml/tests/021.phpt.
php · Jul 30, 2020 · 3690a80 · 3690a80
1 parent 849c741
commit 3690a80
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/ext/opcache/jit/zend_jit_x86.dasc b/ext/opcache/jit/zend_jit_x86.dasc
@@ -1613,6 +1613,7 @@ static uint32_t ones32(uint32_t x)
 
 static uint32_t floor_log2(uint32_t x)
 {
+	ZEND_ASSERT(x != 0);
 	x |= (x >> 1);
 	x |= (x >> 2);
 	x |= (x >> 4);
@@ -1623,7 +1624,7 @@ static uint32_t floor_log2(uint32_t x)
 
 static zend_bool is_power_of_two(uint32_t x)
 {
-	return !(x & (x - 1));
+	return !(x & (x - 1)) && x != 0;
 }
 
 static zend_bool has_concrete_type(uint32_t value_type)