https://gcc.gnu.org/g:b4cf69503bcb32491dbd7ab63fe7f0f9fcdcca38
commit r15-9486-gb4cf69503bcb32491dbd7ab63fe7f0f9fcdcca38
Author: Martin Jambor <mjam...@suse.cz>
Date: Tue Apr 15 15:55:34 2025 +0200
ipa-bit-cp: Fix adjusting value according to mask (PR119803)
In my fix for PR 119318 I put mask calculation in
ipcp_bits_lattice::meet_with_1 above a final fix to value so that all
the bits in the value which are meaningless according to mask have
value zero, which has tripped a validator in PR 119803. This patch
fixes that by moving the adjustment down.
Even thought the fix for PR 119318 did a similar thing in
ipcp_bits_lattice::meet_with, the same is not necessary because that
code path then feeds the new value and mask to
ipcp_bits_lattice::set_to_constant which does the final adjustment
correctly.
In both places, however, Jakup proposed a better way of calculating
cap_mask and so I have changed it accordingly.
gcc/ChangeLog:
2025-04-15 Martin Jambor <mjam...@suse.cz>
PR ipa/119803
* ipa-cp.cc (ipcp_bits_lattice::meet_with_1): Move m_value adjustmed
according to m_mask below the adjustment of the latter according to
cap_mask. Optimize the calculation of cap_mask a bit.
(ipcp_bits_lattice::meet_with): Optimize the calculation of
cap_mask a
bit.
gcc/testsuite/ChangeLog:
2025-04-15 Martin Jambor <mjam...@suse.cz>
PR ipa/119803
* gcc.dg/ipa/pr119803.c: New test.
Co-authored-by: Jakub Jelinek <ja...@redhat.com>
Diff:
---
gcc/ipa-cp.cc | 6 +++---
gcc/testsuite/gcc.dg/ipa/pr119803.c | 16 ++++++++++++++++
2 files changed, 19 insertions(+), 3 deletions(-)
diff --git a/gcc/ipa-cp.cc b/gcc/ipa-cp.cc
index 379fbc5dd637..806c2bdc97f2 100644
--- a/gcc/ipa-cp.cc
+++ b/gcc/ipa-cp.cc
@@ -933,13 +933,13 @@ ipcp_bits_lattice::meet_with_1 (widest_int value,
widest_int mask,
m_mask = (m_mask | mask) | (m_value ^ value);
if (drop_all_ones)
m_mask |= m_value;
- m_value &= ~m_mask;
- widest_int cap_mask = wi::bit_not (wi::sub (wi::lshift (1, precision), 1));
+ widest_int cap_mask = wi::shifted_mask <widest_int> (0, precision, true);
m_mask |= cap_mask;
if (wi::sext (m_mask, precision) == -1)
return set_to_bottom ();
+ m_value &= ~m_mask;
return m_mask != old_mask;
}
@@ -1015,7 +1015,7 @@ 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));
+ widest_int cap_mask = wi::shifted_mask <widest_int> (0, precision, true);
adjusted_mask |= cap_mask;
if (wi::sext (adjusted_mask, precision) == -1)
return set_to_bottom ();
diff --git a/gcc/testsuite/gcc.dg/ipa/pr119803.c
b/gcc/testsuite/gcc.dg/ipa/pr119803.c
new file mode 100644
index 000000000000..1a7bfd25018a
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ipa/pr119803.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+extern void f(int p);
+int a, b;
+char c;
+static int d(int e) { return !e || a == 1 ? 0 : a / e; }
+static void h(short e) {
+ int g = d(e);
+ f(g);
+}
+void i() {
+ c = 128;
+ h(c);
+ b = d(65536);
+}
