Hi. In order to fix the PR, I save temporary expression to a SSA_NAME that is then used in the gcall.
Patch can bootstrap on ppc64le-redhat-linux and survives regression tests. Ready to be installed? Martin gcc/ChangeLog: 2017-12-22 Martin Liska <mli...@suse.cz> PR tree-optimization/83552 * tree-ssa-strlen.c (fold_strstr_to_strncmp): Assign result of get_string_lenth to a SSA_NAME. gcc/testsuite/ChangeLog: 2017-12-22 Martin Liska <mli...@suse.cz> PR tree-optimization/83552 * gcc.dg/pr83552.c: New test. --- gcc/testsuite/gcc.dg/pr83552.c | 13 +++++++++++++ gcc/tree-ssa-strlen.c | 7 ++++++- 2 files changed, 19 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.dg/pr83552.c
diff --git a/gcc/testsuite/gcc.dg/pr83552.c b/gcc/testsuite/gcc.dg/pr83552.c new file mode 100644 index 00000000000..993cdd26581 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr83552.c @@ -0,0 +1,13 @@ +/* PR tree-optimization/83364 */ +/* { dg-options "-O2" } */ + +char *b; +char d[100]; +void a (); +void +c (void) +{ + __builtin_strcat (d, "12345"); + if (__builtin_strstr (b, d) == b) + a (); +} diff --git a/gcc/tree-ssa-strlen.c b/gcc/tree-ssa-strlen.c index e812bd1e735..43dc22d5ce0 100644 --- a/gcc/tree-ssa-strlen.c +++ b/gcc/tree-ssa-strlen.c @@ -3005,12 +3005,17 @@ fold_strstr_to_strncmp (tree rhs1, tree rhs2, gimple *stmt) { gimple_stmt_iterator gsi = gsi_for_stmt (call_stmt); tree strncmp_decl = builtin_decl_explicit (BUILT_IN_STRNCMP); + + tree arg1_len_tmp = make_ssa_name (TREE_TYPE (arg1_len)); + gassign *arg1_stmt = gimple_build_assign (arg1_len_tmp, arg1_len); gcall *strncmp_call = gimple_build_call (strncmp_decl, 3, - arg0, arg1, arg1_len); + arg0, arg1, + arg1_len_tmp); tree strncmp_lhs = make_ssa_name (integer_type_node); gimple_set_vuse (strncmp_call, gimple_vuse (call_stmt)); gimple_call_set_lhs (strncmp_call, strncmp_lhs); gsi_remove (&gsi, true); + gsi_insert_before (&gsi, arg1_stmt, GSI_SAME_STMT); gsi_insert_before (&gsi, strncmp_call, GSI_SAME_STMT); tree zero = build_zero_cst (TREE_TYPE (strncmp_lhs));