[gcc r12-10455] tree-optimization/112495 - alias versioning and address spaces

[Richard Biener via Gcc-cvs]

https://gcc.gnu.org/g:dbb5273996259b04350a1e3d35e633c51fc9310f

commit r12-10455-gdbb5273996259b04350a1e3d35e633c51fc9310f
Author: Richard Biener <rguent...@suse.de>
Date:   Mon Nov 13 10:20:37 2023 +0100

    tree-optimization/112495 - alias versioning and address spaces
    
    We are not correctly handling differing address spaces in dependence
    analysis runtime alias check generation so refuse to do that.
    
            PR tree-optimization/112495
            * tree-data-ref.cc (runtime_alias_check_p): Reject checks
            between different address spaces.
    
            * gcc.target/i386/pr112495.c: New testcase.
    
    (cherry picked from commit 0f593c0521caab8cfac53514b1a5e7d0d0dd1932)

Diff:
---
 gcc/testsuite/gcc.target/i386/pr112495.c | 12 ++++++++++++
 gcc/tree-data-ref.cc                     |  7 +++++++
 2 files changed, 19 insertions(+)

diff --git a/gcc/testsuite/gcc.target/i386/pr112495.c 
b/gcc/testsuite/gcc.target/i386/pr112495.c
new file mode 100644
index 000000000000..21afbaa6945d
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr112495.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-O3" } */
+
+typedef struct { int v; } T1;
+typedef struct { T1 v[32]; } T2;
+
+T1 s;
+T1 f1() { return s; }
+
+void f2(__seg_gs T2 *p, int n) {
+  for (int i = 0; i < n; ++i) p->v[i] = f1();
+}
diff --git a/gcc/tree-data-ref.cc b/gcc/tree-data-ref.cc
index 397792c3584c..0df4a3525f4c 100644
--- a/gcc/tree-data-ref.cc
+++ b/gcc/tree-data-ref.cc
@@ -1632,6 +1632,13 @@ runtime_alias_check_p (ddr_p ddr, class loop *loop, bool 
speed_p)
                                   "runtime alias check not supported for"
                                   " outer loop.\n");
 
+  /* FORNOW: We don't support handling different address spaces.  */
+  if (TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (DR_BASE_ADDRESS (DDR_A (ddr)))))
+      != TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (DR_BASE_ADDRESS (DDR_B 
(ddr))))))
+    return opt_result::failure_at (DR_STMT (DDR_A (ddr)),
+                                  "runtime alias check between different "
+                                  "address spaces not supported.\n");
+
   return opt_result::success ();
 }