After the propagation of constants and value ranges, it turns out
that the propagation of known bits also needs to be made aware of any
intermediate types in which any arithmetic operations are made and
must limit its precision there. This implements just that, using the
newly collected and streamed types of the operations involved.
Bootstrapped and tested and LTO bootstrapped on x86_64-linux. OK for
master?
Thanks,
Martin
gcc/ChangeLog:
2025-03-20 Martin Jambor <mjam...@suse.cz>
PR ipa/119318
* ipa-cp.cc (ipcp_bits_lattice::meet_with_1): Set all mask bits
not covered by precision to one.
(ipcp_bits_lattice::meet_with): Likewise.
(propagate_bits_across_jump_function): Use the first operand type
rather than the final parameter one to perform meet with other
lattices. Check the operation conforms with
expr_type_first_operand_type_p.
* tree.cc (expr_type_first_operand_type_p): Add POINTER_PLUS_EXPR.
gcc/testsuite/ChangeLog:
2025-03-18 Martin Jambor <mjam...@suse.cz>
PR ipa/119318
* gcc.dg/ipa/pr119318.c: New test.
---
gcc/ipa-cp.cc | 32 ++++++++++++++++++++----
gcc/testsuite/gcc.dg/ipa/pr119318.c | 38 +++++++++++++++++++++++++++++
2 files changed, 65 insertions(+), 5 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/ipa/pr119318.c
diff --git a/gcc/ipa-cp.cc b/gcc/ipa-cp.cc
index 264568989a9..cdedbaaf859 100644
--- a/gcc/ipa-cp.cc
+++ b/gcc/ipa-cp.cc
@@ -918,6 +918,8 @@ ipcp_bits_lattice::meet_with_1 (widest_int value,
widest_int mask,
m_mask |= m_value;
m_value &= ~m_mask;
+ widest_int cap_mask = wi::bit_not (wi::sub (wi::lshift (1, precision), 1));
+ m_mask |= cap_mask;
if (wi::sext (m_mask, precision) == -1)
return set_to_bottom ();
@@ -996,6 +998,8 @@ ipcp_bits_lattice::meet_with (ipcp_bits_lattice& other,
unsigned precision,
adjusted_mask |= adjusted_value;
adjusted_value &= ~adjusted_mask;
}
+ widest_int cap_mask = wi::bit_not (wi::sub (wi::lshift (1, precision),
1));
+ adjusted_mask |= cap_mask;
if (wi::sext (adjusted_mask, precision) == -1)
return set_to_bottom ();
return set_to_constant (adjusted_value, adjusted_mask);
@@ -2507,14 +2511,12 @@ propagate_bits_across_jump_function (cgraph_edge *cs,
int idx,
return dest_lattice->set_to_bottom ();
}
- unsigned precision = TYPE_PRECISION (parm_type);
- signop sgn = TYPE_SIGN (parm_type);
-
if (jfunc->type == IPA_JF_PASS_THROUGH
|| jfunc->type == IPA_JF_ANCESTOR)
{
ipa_node_params *caller_info = ipa_node_params_sum->get (cs->caller);
tree operand = NULL_TREE;
+ tree op_type = NULL_TREE;
enum tree_code code;
unsigned src_idx;
bool keep_null = false;
@@ -2524,7 +2526,10 @@ propagate_bits_across_jump_function (cgraph_edge *cs,
int idx,
code = ipa_get_jf_pass_through_operation (jfunc);
src_idx = ipa_get_jf_pass_through_formal_id (jfunc);
if (code != NOP_EXPR)
- operand = ipa_get_jf_pass_through_operand (jfunc);
+ {
+ operand = ipa_get_jf_pass_through_operand (jfunc);
+ op_type = ipa_get_jf_pass_through_op_type (jfunc);
+ }
}
else
{
@@ -2551,6 +2556,22 @@ propagate_bits_across_jump_function (cgraph_edge *cs,
int idx,
if (!src_lats->bits_lattice.bottom_p ())
{
+ if (!op_type)
+ {
+ op_type = ipa_get_type (caller_info, src_idx);
+ if (!op_type)
+ {
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, "Setting dest_lattice to bottom, "
+ "because the operation involved in computing "
+ "param %i of %s is in an unknown type.\n",
+ idx, cs->callee->dump_name ());
+ return dest_lattice->set_to_bottom ();
+ }
+ }
+
+ unsigned precision = TYPE_PRECISION (op_type);
+ signop sgn = TYPE_SIGN (op_type);
bool drop_all_ones
= keep_null && !src_lats->bits_lattice.known_nonzero_p ();
@@ -2570,7 +2591,8 @@ propagate_bits_across_jump_function (cgraph_edge *cs, int
idx,
= widest_int::from (bm.mask (), TYPE_SIGN (parm_type));
widest_int value
= widest_int::from (bm.value (), TYPE_SIGN (parm_type));
- return dest_lattice->meet_with (value, mask, precision);
+ return dest_lattice->meet_with (value, mask,
+ TYPE_PRECISION (parm_type));
}
}
return dest_lattice->set_to_bottom ();
diff --git a/gcc/testsuite/gcc.dg/ipa/pr119318.c
b/gcc/testsuite/gcc.dg/ipa/pr119318.c
new file mode 100644
index 00000000000..8e62ec5e350
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ipa/pr119318.c
@@ -0,0 +1,38 @@
+/* { dg-do run } */
+/* { dg-require-effective-target int128 } */
+/* { dg-additional-options "-Wno-psabi -w" } */
+/* { dg-options "-Wno-psabi -O2" } */
+
+typedef unsigned V __attribute__((vector_size (64)));
+typedef unsigned __int128 W __attribute__((vector_size (64)));
+
+W a;
+W b;
+W c = { -0xffff, -0xffff, -0xffff, -0xffff };
+
+static __attribute__((__noinline__, __noclone__)) W
+bar (unsigned __int128 u)
+{
+ return u + c;
+}
+
+static inline W
+foo (unsigned short s, V v)
+{
+ V y = (V) bar ((unsigned short) ~s);
+ v >>= y;
+ b ^= (W) a;
+ v *= v;
+ return (W) v + b;
+}
+
+
+int
+main ()
+{
+ W x = foo (0, (V) { 0, 5 });
+ for (unsigned i = 0; i < sizeof(x)/sizeof(x[0]); i++)
+ if (x[i] != (i ? 0 : 0x1900000000))
+ __builtin_abort();
+ return 0;
+}
--
2.48.1
