From ce81282261c6c77883b17d0ebfbbe337bed76457 Mon Sep 17 00:00:00 2001 From: Aldy Hernandez Date: Thu, 13 May 2021 16:09:58 -0400 Subject: [PATCH] Bail in bounds_of_var_in_loop if scev returns NULL. Both initial_condition_in_loop_num and evolution_part_in_loop_num can return NULL. This patch exits if either one is NULL. Presumably this didn't happen before, because adjust_range_with_scev was called far less frequently than in ranger, which can call it for every PHI. gcc/ChangeLog: PR tree-optimization/100349 * vr-values.c (bounds_of_var_in_loop): Bail if scev returns NULL. gcc/testsuite/ChangeLog: * gcc.dg/pr100349.c: New test. --- gcc/testsuite/gcc.dg/pr100349.c | 16 ++++++++++++++++ gcc/vr-values.c | 3 +++ 2 files changed, 19 insertions(+) create mode 100644 gcc/testsuite/gcc.dg/pr100349.c diff --git a/gcc/testsuite/gcc.dg/pr100349.c b/gcc/testsuite/gcc.dg/pr100349.c new file mode 100644 index 0000000..dd7977a --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr100349.c @@ -0,0 +1,16 @@ +// { dg-do compile } +// { dg-options "-O2 -w" } + +#include +uint8_t a; +b(int8_t c) { + int d; +e: + uint32_t f; + for (;;) + for (c = 10; c; c++) + if (0 > (a = c) ?: d) { + f = a; + goto e; + } +} diff --git a/gcc/vr-values.c b/gcc/vr-values.c index 08b237b..b1bf53a 100644 --- a/gcc/vr-values.c +++ b/gcc/vr-values.c @@ -1650,6 +1650,9 @@ bounds_of_var_in_loop (tree *min, tree *max, range_query *query, init = initial_condition_in_loop_num (chrec, loop->num); step = evolution_part_in_loop_num (chrec, loop->num); + if (!init || !step) + return false; + /* If INIT is an SSA with a singleton range, set INIT to said singleton, otherwise leave INIT alone. */ if (TREE_CODE (init) == SSA_NAME) -- 2.7.4