2019-01-17  Jakub Jelinek  <jakub@redhat.com>

	PR bootstrap/88714
	* config/arm/ldrdstrd.md: If alias sets on the SImode MEMs are
	different, clear alias set on the DImode MEM.  Clear MEM_EXPR.

	* gcc.c-torture/execute/pr88714.c: New test.

--- gcc/config/arm/ldrdstrd.md.jj	2019-01-16 09:35:03.851334889 +0100
+++ gcc/config/arm/ldrdstrd.md	2019-01-17 17:37:40.860791779 +0100
@@ -39,6 +39,10 @@ (define_peephole2 ; ldrd
     /* In ARM state, the destination registers of LDRD/STRD must be
        consecutive. We emit DImode access.  */
     operands[0] = gen_rtx_REG (DImode, REGNO (operands[0]));
+    if (MEM_ALIAS_SET (operands[2])
+	&& MEM_ALIAS_SET (operands[2]) != MEM_ALIAS_SET (operands[3]))
+      set_mem_alias_set (operands[2], 0);
+    set_mem_expr (operands[2], NULL_TREE);
     operands[2] = adjust_address (operands[2], DImode, 0);
     /* Emit [(set (match_dup 0) (match_dup 2))] */
     emit_insn (gen_rtx_SET (operands[0], operands[2]));
@@ -71,6 +75,10 @@ (define_peephole2 ; strd
     /* In ARM state, the destination registers of LDRD/STRD must be
        consecutive. We emit DImode access.  */
     operands[0] = gen_rtx_REG (DImode, REGNO (operands[0]));
+    if (MEM_ALIAS_SET (operands[2])
+	&& MEM_ALIAS_SET (operands[2]) != MEM_ALIAS_SET (operands[3]))
+      set_mem_alias_set (operands[2], 0);
+    set_mem_expr (operands[2], NULL_TREE);
     operands[2] = adjust_address (operands[2], DImode, 0);
     /* Emit [(set (match_dup 2) (match_dup 0))]  */
     emit_insn (gen_rtx_SET (operands[2], operands[0]));
@@ -106,6 +114,10 @@ (define_peephole2 ; strd of constants
   else if (TARGET_ARM)
   {
    rtx tmp = gen_rtx_REG (DImode, REGNO (operands[0]));
+    if (MEM_ALIAS_SET (operands[2])
+	&& MEM_ALIAS_SET (operands[2]) != MEM_ALIAS_SET (operands[3]))
+      set_mem_alias_set (operands[2], 0);
+    set_mem_expr (operands[2], NULL_TREE);
    operands[2] = adjust_address (operands[2], DImode, 0);
    /* Emit the pattern:
       [(set (match_dup 0) (match_dup 4))
@@ -149,6 +161,10 @@ (define_peephole2 ; strd of constants
   else if (TARGET_ARM)
   {
    rtx tmp = gen_rtx_REG (DImode, REGNO (operands[0]));
+    if (MEM_ALIAS_SET (operands[2])
+	&& MEM_ALIAS_SET (operands[2]) != MEM_ALIAS_SET (operands[3]))
+      set_mem_alias_set (operands[2], 0);
+    set_mem_expr (operands[2], NULL_TREE);
    operands[2] = adjust_address (operands[2], DImode, 0);
    /* Emit the pattern
       [(set (match_dup 0) (match_dup 4))
@@ -203,6 +219,10 @@ (define_peephole2 ; swap the destination
     else
      {
         operands[0] = gen_rtx_REG (DImode, REGNO (operands[0]));
+	if (MEM_ALIAS_SET (operands[2])
+	    && MEM_ALIAS_SET (operands[2]) != MEM_ALIAS_SET (operands[3]))
+	  set_mem_alias_set (operands[2], 0);
+	set_mem_expr (operands[2], NULL_TREE);
         operands[2] = adjust_address (operands[2], DImode, 0);
      }
    }
@@ -238,6 +258,10 @@ (define_peephole2 ; swap the destination
     else
      {
         operands[0] = gen_rtx_REG (DImode, REGNO (operands[0]));
+	if (MEM_ALIAS_SET (operands[2])
+	    && MEM_ALIAS_SET (operands[2]) != MEM_ALIAS_SET (operands[3]))
+	  set_mem_alias_set (operands[2], 0);
+	set_mem_expr (operands[2], NULL_TREE);
         operands[2] = adjust_address (operands[2], DImode, 0);
      }
    }
--- gcc/testsuite/gcc.c-torture/execute/pr88714.c.jj	2019-01-17 17:39:42.074828164 +0100
+++ gcc/testsuite/gcc.c-torture/execute/pr88714.c	2019-01-17 17:21:26.810575783 +0100
@@ -0,0 +1,43 @@
+/* PR bootstrap/88714 */
+
+struct S { int a, b, c; int *d; };
+struct T { int *e, *f, *g; } *t = 0;
+int *o = 0;
+
+__attribute__((noipa))
+void bar (int *x, int y, int z, int w)
+{
+  if (w == -1)
+    {
+      if (x != 0 || y != 0 || z != 0)
+	__builtin_abort ();
+    }
+  else if (w != 0 || x != t->g || y != 0 || z != 12)
+    __builtin_abort ();
+}
+
+__attribute__((noipa)) void
+foo (struct S *x, struct S *y, int *z, int w)
+{
+  *o = w;
+  if (w)
+    bar (0, 0, 0, -1);
+  x->d = z;
+  if (y->d)
+    y->c = y->c + y->d[0];
+  bar (t->g, 0, y->c, 0);
+}
+
+int
+main ()
+{
+  int a[4] = { 8, 9, 10, 11 };
+  struct S s = { 1, 2, 3, &a[0] };
+  struct T u = { 0, 0, &a[3] };
+  o = &a[2];
+  t = &u;
+  foo (&s, &s, &a[1], 5);
+  if (s.c != 12 || s.d != &a[1])
+    __builtin_abort ();
+  return 0;
+}