https://gcc.gnu.org/g:dba5d112691a3e10b722468d94fffeda0fdbb818
commit r16-365-gdba5d112691a3e10b722468d94fffeda0fdbb818
Author: Andrew Pinski <quic_apin...@quicinc.com>
Date: Fri May 2 09:46:24 2025 -0700
simplify-rtl: Fix crash due to simplify_with_subreg_not [PR120059]
r16-286-gd84fbc516ea57d added a call to simplify_gen_subreg but didn't
check if the result of simplify_gen_subreg was non-null. simplify_gen_subreg
can return NULL if the subreg would be not valid. In the case below we had
a hard register for the SSE register xmm0 of mode SI and doing a subreg to
QI mode but QImode is not a valid mode for the SSE register so
simplify_gen_subreg
would return NULL.
This adds the obvious check.
Pushed as obvious after bootstrap/test on x86_64-linux-gnu.
PR rtl-optimization/120059
gcc/ChangeLog:
* simplify-rtx.cc (simplify_with_subreg_not): Check the result
of simplify_gen_subreg.
gcc/testsuite/ChangeLog:
* gcc.dg/torture/pr120059-1.c: New test.
Signed-off-by: Andrew Pinski <quic_apin...@quicinc.com>
Diff:
---
gcc/simplify-rtx.cc | 4 ++++
gcc/testsuite/gcc.dg/torture/pr120059-1.c | 17 +++++++++++++++++
2 files changed, 21 insertions(+)
diff --git a/gcc/simplify-rtx.cc b/gcc/simplify-rtx.cc
index 7c4d8e6cfdbb..7bcbe11370fa 100644
--- a/gcc/simplify-rtx.cc
+++ b/gcc/simplify-rtx.cc
@@ -3063,6 +3063,10 @@ simplify_with_subreg_not (rtx_code binop, machine_mode
mode, rtx op0, rtx op1)
XEXP (SUBREG_REG (opn), 0),
GET_MODE (SUBREG_REG (opn)),
SUBREG_BYTE (opn));
+
+ if (!new_subreg)
+ return NULL_RTX;
+
rtx new_not = simplify_gen_unary (NOT, mode, new_subreg, mode);
if (opn == op0)
return simplify_gen_binary (binop, mode, new_not, op1);
diff --git a/gcc/testsuite/gcc.dg/torture/pr120059-1.c
b/gcc/testsuite/gcc.dg/torture/pr120059-1.c
new file mode 100644
index 000000000000..36d0c5b00690
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr120059-1.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-options "-g" } */
+
+/* PR rtl-optimization/120059 */
+
+int a[4];
+int c, d;
+void f(void) {
+ for (int e = 0; e < 4; e++)
+ a[e] = e | c;
+ int b = 0;
+ if ((a[0] & 1) && (a[0] & 4))
+ b = 2;
+ if (a[0] & 16)
+ b |= 1;
+ d = ~b;
+}
