re PR rtl-optimization/91173 (ICE: in int_mode_for_mode, at stor-layout.c:403)

PR rtl-optimization/91173

	Backported from mainline
	2019-07-16  Jeff Law  <law@redhat.com>

	PR rtl-optimization/91173
	* tree-ssa-address.c (addr_for_mem_ref): If the base is an
	SSA_NAME with a constant value, fold its value into the offset
	and clear the base before calling gen_addr_rtx.
	* g++.dg/pr91173.C: New test.

From-SVN: r273741

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index b480c19dba478d122e93a3df6c6b5709384f5571..cf38fd1f5128dba9b79f7c8ee759f58cfa97236e 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,14 @@
+2019-07-23  Matthew Beliveau  <mbelivea@redhat.com>
+       
+       Backported from mainline
+       2019-07-16  Jeff Law  <law@redhat.com>
+       
+       PR rtl-optimization/91173
+       * tree-ssa-address.c (addr_for_mem_ref): If the base is an
+       SSA_NAME with a constant value, fold its value into the offset
+       and clear the base before calling gen_addr_rtx.
+       * g++.dg/pr91173.C: New test.
+
 2019-07-23  Richard Biener  <rguenther@suse.de>
 
        PR debug/91231

diff --git a/gcc/testsuite/g++.dg/pr91173.C b/gcc/testsuite/g++.dg/pr91173.C
new file mode 100644 (file)
index 0000000..b8fb41b
--- /dev/null
+++ b/gcc/testsuite/g++.dg/pr91173.C
@@ -0,0 +1,45 @@
+class a {
+  int b;
+  void *c;
+
+public:
+  bool aa();
+  int &ab() {
+    if (aa()) {
+      void *d(c);
+      return static_cast<int *>(d)[b];
+    }
+    return *(int *)0;
+  }
+};
+typedef enum {E} e;
+class f : public a {
+  int g;
+
+public:
+  int ac() {
+    if (g)
+      return 1;
+    return ac();
+  }
+};
+int *ad;
+struct h {
+  static int ae(e, int *m) {
+    f ag;
+    int *ah;
+    while (!0) {
+      ad = &ag.ab();
+      ah = ad + ag.ac();
+      while (ad < ah)
+        *m = *ad++;
+    }
+  }
+};
+template <class, class>
+void i(int *, int *, int, int *, e n, int *o) {
+  h::ae(n, o);
+}
+int aq, ar, as, at, au;
+void aw() { i<int, bool>(&aq, &ar, as, &at, (e)0, &au); }
+

diff --git a/gcc/tree-ssa-address.c b/gcc/tree-ssa-address.c
index 1c17e935914d6b4af092cf8ea10ff76ce796e3fc..2e5d87734d657bb1ed0b6c3c8807fb57f97971a7 100644 (file)
--- a/gcc/tree-ssa-address.c
+++ b/gcc/tree-ssa-address.c
@@ -259,6 +259,20 @@ addr_for_mem_ref (struct mem_address *addr, addr_space_t as,
         ? expand_expr (addr->index, NULL_RTX, pointer_mode, EXPAND_NORMAL)
         : NULL_RTX);
 
+  /* addr->base could be an SSA_NAME that was set to a constant value.  The
+     call to expand_expr may expose that constant.  If so, fold the value
+     into OFF and clear BSE.  Otherwise we may later try to pull a mode from
+     BSE to generate a REG, which won't work with constants because they
+     are modeless.  */
+  if (bse && GET_CODE (bse) == CONST_INT)
+    {
+      if (off)
+       off = simplify_gen_binary (PLUS, pointer_mode, bse, off);
+      else
+       off = bse;
+      gcc_assert (GET_CODE (off) == CONST_INT);
+      bse = NULL_RTX;
+    }
   gen_addr_rtx (pointer_mode, sym, bse, idx, st, off, &address, NULL, NULL);
   if (pointer_mode != address_mode)
     address = convert_memory_address (address_mode, address);