From 4a46a48ebc7b7b3976af49f6f8dabd65c6ddf64b Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Sat, 23 Mar 2024 11:20:00 +0100 Subject: bitint: Fix bitfield loads in handle_cast [PR114433] We ICE on the following testcase, because handle_cast was incorrectly testing !m_first to see whether it should use m_data[m_bitfld_load + 1] or fresh SSA_NAME for a PHI result. Now, m_first is in the routine sometimes temporarily cleared in between doing prepare_data_in_out and the !m_first check and only before returning restored from the save_first copy. Without this patch, we try to use the same SSA_NAME (_12 here) in 2 different PHI results which is obviously invalid IL and ICEs very quickly. 2024-03-23 Jakub Jelinek PR tree-optimization/114433 * gimple-lower-bitint.cc (bitint_large_huge::handle_cast): For m_bitfld_load check save_first rather than m_first. * gcc.dg/torture/bitint-68.c: New test. --- gcc/gimple-lower-bitint.cc | 2 +- gcc/testsuite/gcc.dg/torture/bitint-68.c | 28 ++++++++++++++++++++++++++++ 2 files changed, 29 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.dg/torture/bitint-68.c (limited to 'gcc') diff --git a/gcc/gimple-lower-bitint.cc b/gcc/gimple-lower-bitint.cc index 6f13c65..40a1084 100644 --- a/gcc/gimple-lower-bitint.cc +++ b/gcc/gimple-lower-bitint.cc @@ -1506,7 +1506,7 @@ bitint_large_huge::handle_cast (tree lhs_type, tree rhs1, tree idx) if (m_bitfld_load) { tree t4; - if (!m_first) + if (!save_first) t4 = m_data[m_bitfld_load + 1]; else t4 = make_ssa_name (m_limb_type); diff --git a/gcc/testsuite/gcc.dg/torture/bitint-68.c b/gcc/testsuite/gcc.dg/torture/bitint-68.c new file mode 100644 index 0000000..8320e8e --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/bitint-68.c @@ -0,0 +1,28 @@ +/* PR tree-optimization/114433 */ +/* { dg-do run { target bitint } } */ +/* { dg-options "-std=c23" } */ +/* { dg-skip-if "" { ! run_expensive_tests } { "*" } { "-O0" "-O2" } } */ +/* { dg-skip-if "" { ! run_expensive_tests } { "-flto" } { "" } } */ + +#if __BITINT_MAXWIDTH__ >= 511 +struct S { int : 31; _BitInt(511) b : 300; } s; + +__attribute__((noipa)) _BitInt(511) +foo (void) +{ + return s.b << 1; +} +#endif + +int +main () +{ +#if __BITINT_MAXWIDTH__ >= 511 + s.b = 642460398785925402356009598661384732715767737595497615767135001949421105426024498988100867wb; + if (foo () != ((_BitInt(511)) 642460398785925402356009598661384732715767737595497615767135001949421105426024498988100867wb) << 1) + __builtin_abort (); + s.b = 2655156766298562299560755420298083843774074962786295887660222690220887wb; + if (foo () != ((_BitInt(511)) 2655156766298562299560755420298083843774074962786295887660222690220887wb) << 1) + __builtin_abort (); +#endif +} -- cgit v1.1