[gcc r15-7790] ipa/119067 - bogus TYPE_PRECISION check on VECTOR_TYPE

[Richard Biener]

https://gcc.gnu.org/g:f22e89167b3abfbf6d67f42fc4d689d8ffdc1810

commit r15-7790-gf22e89167b3abfbf6d67f42fc4d689d8ffdc1810
Author: Richard Biener <rguenther@suse.de>
Date:   Mon Mar 3 09:54:15 2025 +0100

    ipa/119067 - bogus TYPE_PRECISION check on VECTOR_TYPE
    
    odr_types_equivalent_p can end up using TYPE_PRECISION on vector
    types which is a no-go.  The following instead uses TYPE_VECTOR_SUBPARTS
    for vector types so we also end up comparing the number of vector elements.
    
            PR ipa/119067
            * ipa-devirt.cc (odr_types_equivalent_p): Check
            TYPE_VECTOR_SUBPARTS for vectors.
    
            * g++.dg/lto/pr119067_0.C: New testcase.
            * g++.dg/lto/pr119067_1.C: Likewise.

Diff:
---
 gcc/ipa-devirt.cc                     | 10 +++++++++-
 gcc/testsuite/g++.dg/lto/pr119067_0.C | 22 ++++++++++++++++++++++
 gcc/testsuite/g++.dg/lto/pr119067_1.C | 10 ++++++++++
 3 files changed, 41 insertions(+), 1 deletion(-)

diff --git a/gcc/ipa-devirt.cc b/gcc/ipa-devirt.cc
index c31658f57ef2..532e25e87c60 100644
--- a/gcc/ipa-devirt.cc
+++ b/gcc/ipa-devirt.cc
@@ -1259,13 +1259,21 @@ odr_types_equivalent_p (tree t1, tree t2, bool warn, bool *warned,
       || TREE_CODE (t1) == OFFSET_TYPE
       || POINTER_TYPE_P (t1))
     {
-      if (TYPE_PRECISION (t1) != TYPE_PRECISION (t2))
+      if (!VECTOR_TYPE_P (t1) && TYPE_PRECISION (t1) != TYPE_PRECISION (t2))
 	{
 	  warn_odr (t1, t2, NULL, NULL, warn, warned,
 		    G_("a type with different precision is defined "
 		       "in another translation unit"));
 	  return false;
 	}
+      if (VECTOR_TYPE_P (t1)
+	  && maybe_ne (TYPE_VECTOR_SUBPARTS (t1), TYPE_VECTOR_SUBPARTS (t2)))
+	{
+	  warn_odr (t1, t2, NULL, NULL, warn, warned,
+		    G_("a vector type with different number of elements "
+		       "is defined in another translation unit"));
+	  return false;
+	}
       if (TYPE_UNSIGNED (t1) != TYPE_UNSIGNED (t2))
 	{
 	  warn_odr (t1, t2, NULL, NULL, warn, warned,
diff --git a/gcc/testsuite/g++.dg/lto/pr119067_0.C b/gcc/testsuite/g++.dg/lto/pr119067_0.C
new file mode 100644
index 000000000000..e0f813ceffed
--- /dev/null
+++ b/gcc/testsuite/g++.dg/lto/pr119067_0.C
@@ -0,0 +1,22 @@
+/* { dg-lto-do link } */
+/* { dg-skip-if "" { ! { x86_64-*-* i?86-*-* } } } */
+/* { dg-require-effective-target avx2 } */
+/* { dg-require-effective-target shared } */
+/* { dg-lto-options { { -O2 -fPIC -flto } } } */
+/* { dg-extra-ld-options { -shared } } */
+
+#pragma GCC push_options
+#pragma GCC target("avx2")
+typedef char __v32qi __attribute__ ((__vector_size__ (32)));
+struct ff
+{
+  __v32qi t;
+};
+__v32qi g(struct ff a);
+
+__v32qi h(__v32qi a)
+{
+  struct ff t = {a};
+  return g(t);
+}
+#pragma GCC pop_options
diff --git a/gcc/testsuite/g++.dg/lto/pr119067_1.C b/gcc/testsuite/g++.dg/lto/pr119067_1.C
new file mode 100644
index 000000000000..d8e2935fa24d
--- /dev/null
+++ b/gcc/testsuite/g++.dg/lto/pr119067_1.C
@@ -0,0 +1,10 @@
+/* { dg-options "-mavx2" } */
+
+typedef char __v32qi __attribute__ ((__vector_size__ (32)));
+struct ff
+{
+  __v32qi t;
+};
+__v32qi g(struct ff a) {
+ return a.t;
+}