| Message ID | ri6y1p0gv37.fsf@suse.cz |
|---|---|
| State | New |
| Headers | show |
| Series | ipa: Avoid IPA confusing scalar values and single-field aggregates (PR 108679) | expand |
On Tue, Feb 14, 2023 at 3:50 PM Martin Jambor <mjambor@suse.cz> wrote: > > Hi, > > PR 108679 testcase shows a situation when IPA-CP is able to track a > scalar constant in a single-field structure that is part of a bigger > structure. This smaller struture is however also passed in a few calls > to other functions, but the two same-but-different entities, originally > places at the same offset and with the same size, and this confuses the > mechanism that takes care of handling call statements after IPA-SRA. > > I think that in stage 4 it is best to revert to GCC 12 behavior in this > particular case (when IPA-CP detects a constant in a single-field > structure or a single element array that is part of a bigger aggregate) > and the patch below does that. If accepted, I plan to file a > missed-optimization bug to track that we could use the IPA-CP propagated > value to re-construct the small aggregate arguments. > > Bootstrapped and tested and LTO bootstrapped on x86_64-linux. OK for > master? OK. Richard. > Thanks, > > Martin > > > > > gcc/ChangeLog: > > 2023-02-13 Martin Jambor <mjambor@suse.cz> > > PR ipa/108679 > * ipa-sra.cc (push_param_adjustments_for_index): Do not omit > creation of non-scalar replacements even if IPA-CP knows their > contents. > > gcc/testsuite/ChangeLog: > > 2023-02-13 Martin Jambor <mjambor@suse.cz> > > PR ipa/108679 > * gcc.dg/ipa/pr108679.c: New test. > --- > gcc/ipa-sra.cc | 2 +- > gcc/testsuite/gcc.dg/ipa/pr108679.c | 25 +++++++++++++++++++++++++ > 2 files changed, 26 insertions(+), 1 deletion(-) > create mode 100644 gcc/testsuite/gcc.dg/ipa/pr108679.c > > diff --git a/gcc/ipa-sra.cc b/gcc/ipa-sra.cc > index 0495f446bf4..3de7d426b7e 100644 > --- a/gcc/ipa-sra.cc > +++ b/gcc/ipa-sra.cc > @@ -3989,7 +3989,7 @@ push_param_adjustments_for_index (isra_func_summary *ifs, unsigned base_index, > { > ipa_argagg_value_list avl (ipcp_ts); > tree value = avl.get_value (base_index, pa->unit_offset); > - if (value) > + if (value && !AGGREGATE_TYPE_P (pa->type)) > { > if (dump_file) > fprintf (dump_file, " - omitting component at byte " > diff --git a/gcc/testsuite/gcc.dg/ipa/pr108679.c b/gcc/testsuite/gcc.dg/ipa/pr108679.c > new file mode 100644 > index 00000000000..b1ed50bb831 > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/ipa/pr108679.c > @@ -0,0 +1,25 @@ > +/* { dg-do compile } */ > +/* { dg-options "-O2" } */ > + > +struct S1 { > + signed f0; > +}; > +struct S2 { > + struct S1 f2; > + short f8; > +} g_18; > +void safe_lshift_func_int16_t_s_u(); > +void safe_unary_minus_func_uint64_t_u(); > +int safe_mul_func_uint8_t_u_u(int, struct S1 p_14); > +int g_732, func_6_l_17; > +static int *func_12(); > +static int func_6(struct S2 p_7) { func_12(func_6_l_17, p_7.f2, g_18, 0); } > +static int *func_12(int, struct S1 p_14) { > + safe_lshift_func_int16_t_s_u(); > + safe_unary_minus_func_uint64_t_u(); > + g_732 = safe_mul_func_uint8_t_u_u(0, p_14); > +} > +int main() { > + struct S2 l_10 = {3}; > + func_6(l_10); > +} > -- > 2.39.1 >
diff --git a/gcc/ipa-sra.cc b/gcc/ipa-sra.cc index 0495f446bf4..3de7d426b7e 100644 --- a/gcc/ipa-sra.cc +++ b/gcc/ipa-sra.cc @@ -3989,7 +3989,7 @@ push_param_adjustments_for_index (isra_func_summary *ifs, unsigned base_index, { ipa_argagg_value_list avl (ipcp_ts); tree value = avl.get_value (base_index, pa->unit_offset); - if (value) + if (value && !AGGREGATE_TYPE_P (pa->type)) { if (dump_file) fprintf (dump_file, " - omitting component at byte " diff --git a/gcc/testsuite/gcc.dg/ipa/pr108679.c b/gcc/testsuite/gcc.dg/ipa/pr108679.c new file mode 100644 index 00000000000..b1ed50bb831 --- /dev/null +++ b/gcc/testsuite/gcc.dg/ipa/pr108679.c @@ -0,0 +1,25 @@ +/* { dg-do compile } */ +/* { dg-options "-O2" } */ + +struct S1 { + signed f0; +}; +struct S2 { + struct S1 f2; + short f8; +} g_18; +void safe_lshift_func_int16_t_s_u(); +void safe_unary_minus_func_uint64_t_u(); +int safe_mul_func_uint8_t_u_u(int, struct S1 p_14); +int g_732, func_6_l_17; +static int *func_12(); +static int func_6(struct S2 p_7) { func_12(func_6_l_17, p_7.f2, g_18, 0); } +static int *func_12(int, struct S1 p_14) { + safe_lshift_func_int16_t_s_u(); + safe_unary_minus_func_uint64_t_u(); + g_732 = safe_mul_func_uint8_t_u_u(0, p_14); +} +int main() { + struct S2 l_10 = {3}; + func_6(l_10); +}