When PTA gets support for special-handling more builtins in
find_func_aliases the corresponding code in find_func_clobbers
needs updating as well since for unhandled cases it assumes
the former will populate ESCAPED accordingly. The following
fixes a few omissions, the testcase runs into the missing strdup
handling. I believe the more advanced handling using modref
results and fnspecs opened a larger gap, the proper fix is to
merge both functions, gating the clobber/use part on a parameter
to avoid diverging.
Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed to trunk.
PR ipa/120006
* tree-ssa-structalias.cc (find_func_clobbers): Handle
strdup, strndup, realloc, index, strchr, strrchr, memchr,
strstr, strpbrk builtins like find_func_aliases does.
* gcc.dg/torture/pr120006.c: New testcase.
---
gcc/testsuite/gcc.dg/torture/pr120006.c | 31 +++++++++++++++++++++
gcc/tree-ssa-structalias.cc | 36 +++++++++++++++++++++++++
2 files changed, 67 insertions(+)
create mode 100644 gcc/testsuite/gcc.dg/torture/pr120006.c
diff --git a/gcc/testsuite/gcc.dg/torture/pr120006.c
b/gcc/testsuite/gcc.dg/torture/pr120006.c
new file mode 100644
index 00000000000..c067f0ef9ca
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr120006.c
@@ -0,0 +1,31 @@
+/* { dg-do run } */
+/* { dg-additional-options "-fipa-pta" } */
+
+char *b;
+int f = 1;
+
+char *xstrdup(char *i) {
+ char *c = __builtin_strdup(i);
+ if (!c)
+ __builtin_exit(1);
+ return c;
+}
+
+int main() {
+ char g;
+ char h[8];
+
+ for (int i = 0; i < 2; i++) {
+ char c = *__builtin_strdup("");
+ b = &g;
+
+ if (f) {
+ h[0] = '-';
+ h[1] = 'a';
+ h[2] = '\0';
+ b = xstrdup(h);
+ }
+ }
+ if (__builtin_strcmp(b, "-a") != 0)
+ __builtin_abort();
+}
diff --git a/gcc/tree-ssa-structalias.cc b/gcc/tree-ssa-structalias.cc
index f79b54284c6..3ad0c69930c 100644
--- a/gcc/tree-ssa-structalias.cc
+++ b/gcc/tree-ssa-structalias.cc
@@ -5583,6 +5583,42 @@ find_func_clobbers (struct function *fn, gimple *origt)
process_ipa_clobber (fi, gimple_call_arg (t, 2));
return;
}
+ /* The following functions use what their first argument
+ points to. */
+ case BUILT_IN_STRDUP:
+ case BUILT_IN_STRNDUP:
+ case BUILT_IN_REALLOC:
+ case BUILT_IN_INDEX:
+ case BUILT_IN_STRCHR:
+ case BUILT_IN_STRRCHR:
+ case BUILT_IN_MEMCHR:
+ {
+ tree src = gimple_call_arg (t, 0);
+ get_constraint_for_ptr_offset (src, NULL_TREE, &rhsc);
+ lhs = get_function_part_constraint (fi, fi_uses);
+ struct constraint_expr *rhsp;
+ FOR_EACH_VEC_ELT (rhsc, i, rhsp)
+ process_constraint (new_constraint (lhs, *rhsp));
+ return;
+ }
+ /* The following functions use what their first and second argument
+ point to. */
+ case BUILT_IN_STRSTR:
+ case BUILT_IN_STRPBRK:
+ {
+ tree src = gimple_call_arg (t, 0);
+ get_constraint_for_ptr_offset (src, NULL_TREE, &rhsc);
+ lhs = get_function_part_constraint (fi, fi_uses);
+ struct constraint_expr *rhsp;
+ FOR_EACH_VEC_ELT (rhsc, i, rhsp)
+ process_constraint (new_constraint (lhs, *rhsp));
+ rhsc.truncate (0);
+ src = gimple_call_arg (t, 1);
+ get_constraint_for_ptr_offset (src, NULL_TREE, &rhsc);
+ FOR_EACH_VEC_ELT (rhsc, i, rhsp)
+ process_constraint (new_constraint (lhs, *rhsp));
+ return;
+ }
/* The following functions neither read nor clobber memory. */
case BUILT_IN_ASSUME_ALIGNED:
case BUILT_IN_FREE:
--
2.43.0
