Given a poiner to array p, tree dumps for expressions like &(*p)[2]
actually show &*p[2]. That's not right -- the parentheses are
important to differentiate indexing into the array the pointer
points to from indexing into the pointer.
The attached patch adjusts the tree pretty printer to add the parens
when the pointer points to an array.
Tested on x86_64-linux.
Martin
PR middle-end/90694 - incorrect representation of ADDR_EXPR involving a pointer to array
gcc/ChangeLog:
PR middle-end/90694
* tree-pretty-print.c (dump_generic_node): Add parentheses.
gcc/testsuite/ChangeLog:
PR middle-end/90694
* gcc.dg/tree-ssa/dump-5.c: New test.
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/dump-5.c b/gcc/testsuite/gcc.dg/tree-ssa/dump-5.c
new file mode 100644
index 00000000000..6807b5e9ef4
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/dump-5.c
@@ -0,0 +1,15 @@
+/* PR middle-end/90694 - incorrect representation of ADDR_EXPR involving
+ a pointer to array
+ { dg-do compile }
+ { dg-options "-fdump-tree-original" } */
+
+typedef char A8[8];
+
+unsigned f (A8 *pa)
+{
+ return __builtin_strlen (&(*pa)[2]);
+}
+
+/* Veriy the expression is correct in the dump:
+ { dg-final { scan-tree-dump-not "\\\&\\\*pa\\\[2\\\]" "original" } }
+ { dg-final { scan-tree-dump "\\\&\\\(\\\*pa\\\)\\\[2\\\]" "original" } } */
diff --git a/gcc/tree-pretty-print.c b/gcc/tree-pretty-print.c
index 6645a646617..30d1d65e6bc 100644
--- a/gcc/tree-pretty-print.c
+++ b/gcc/tree-pretty-print.c
@@ -1676,9 +1676,17 @@ dump_generic_node (pretty_printer *pp, tree node, int spc, dump_flags_t flags,
{
if (TREE_CODE (TREE_OPERAND (node, 0)) != ADDR_EXPR)
{
+ /* Enclose pointers to arrays in parentheses. */
+ tree op0 = TREE_OPERAND (node, 0);
+ tree op0type = TREE_TYPE (op0);
+ if (POINTER_TYPE_P (op0type)
+ && TREE_CODE (TREE_TYPE (op0type)) == ARRAY_TYPE)
+ pp_left_paren (pp);
pp_star (pp);
- dump_generic_node (pp, TREE_OPERAND (node, 0),
- spc, flags, false);
+ dump_generic_node (pp, op0, spc, flags, false);
+ if (POINTER_TYPE_P (op0type)
+ && TREE_CODE (TREE_TYPE (op0type)) == ARRAY_TYPE)
+ pp_right_paren (pp);
}
else
dump_generic_node (pp,
