re PR tree-optimization/65077 (memcpy generates incorrect code with floating point...

2015-02-16  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/65077
	* tree-ssa-structalias.c (get_constraint_for_1): Handle
	IMAGPART_EXPR, REALPART_EXPR and BIT_FIELD_REF.
	(find_func_aliases): Allow float values to carry pointers again.

	* gcc.dg/torture/pr65077.c: New testcase.

From-SVN: r220741

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index a4994293eb2b9523de1b500a230aff9f2ea927d4..061e0341c5091c8e4e8b790a40c155bca2ff108a 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2015-02-16  Richard Biener  <rguenther@suse.de>
+
+       PR tree-optimization/65077
+       * tree-ssa-structalias.c (get_constraint_for_1): Handle
+       IMAGPART_EXPR, REALPART_EXPR and BIT_FIELD_REF.
+       (find_func_aliases): Allow float values to carry pointers again.
+
 2015-02-16  James Greenhalgh  <james.greenhalgh@arm.com>
 
        * doc/install.texi (Specific): Reorder targets list to put

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index abc735816a2fb65972aebc4de8ee93f0fddabb9a..8af42fa44582893d241e42e4324a1c4ddcb42c61 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2015-02-16  Richard Biener  <rguenther@suse.de>
+
+       PR tree-optimization/65077
+       * gcc.dg/torture/pr65077.c: New testcase.
+
 2015-02-16  Alex Velenko  <Alex.Velenko@arm.com>
 
        * gcc.target/aarch64/atomic-op-consume.c (scan-assember-times):

diff --git a/gcc/testsuite/gcc.dg/torture/pr65077.c b/gcc/testsuite/gcc.dg/torture/pr65077.c
new file mode 100644 (file)
index 0000000..f57356c
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr65077.c
@@ -0,0 +1,70 @@
+/* { dg-do run } */
+
+extern void abort (void);
+extern void *memcpy(void *, const void *, __SIZE_TYPE__);
+
+typedef struct {
+    void *v1;
+    void *v2;
+    void *v3;
+    union {
+       void *f1;
+       void *f2;
+    } u;
+} S;
+
+
+S *getS();
+void verify_p(void *p);
+double *getP(void *p);
+
+void memcpy_bug()
+{
+  S *s;
+  double *p = getP(0);
+
+  if (p) {
+      int intSptr[sizeof(S*)/sizeof(int)];
+      unsigned i = 0;
+      for (i = 0; i < sizeof(intSptr)/sizeof(*intSptr); ++i) {
+         intSptr[i] = (int) p[i];
+      }
+      memcpy(&s, intSptr, sizeof(intSptr));
+      (s)->u.f1 = p;
+      verify_p((s)->u.f1);      
+  } else {
+      s = getS();
+  }
+  verify_p(s->u.f1);
+}
+
+double P[4];
+
+double *getP(void *p) {
+    union u {
+       void *p;
+       int i[2];
+    } u;
+    u.p = P;
+    P[0] = u.i[0];
+    P[1] = u.i[1];
+    return P;
+}
+
+S *getS()
+{
+  return 0;
+}
+
+void verify_p(void *p)
+{
+  if (p != P)
+    abort ();
+}
+
+int main(int argc, char *argv[])
+{
+    memcpy_bug();
+    return 0;
+}
+

diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index 4c43b75730d64c5f9fe9250c7facd79d41c2f70a..fd0f5359dd78a702356d1b0696a708a3c9d0c3e4 100644 (file)
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -3492,6 +3492,9 @@ get_constraint_for_1 (tree t, vec<ce_s> *results, bool address_p,
          case ARRAY_REF:
          case ARRAY_RANGE_REF:
          case COMPONENT_REF:
+         case IMAGPART_EXPR:
+         case REALPART_EXPR:
+         case BIT_FIELD_REF:
            get_constraint_for_component_ref (t, results, address_p, lhs_p);
            return;
          case VIEW_CONVERT_EXPR:
@@ -4712,11 +4715,7 @@ find_func_aliases (struct function *fn, gimple origt)
 
          get_constraint_for (lhsop, &lhsc);
 
-         if (FLOAT_TYPE_P (TREE_TYPE (lhsop)))
-           /* If the operation produces a floating point result then
-              assume the value is not produced to transfer a pointer.  */
-           ;
-         else if (code == POINTER_PLUS_EXPR)
+         if (code == POINTER_PLUS_EXPR)
            get_constraint_for_ptr_offset (gimple_assign_rhs1 (t),
                                           gimple_assign_rhs2 (t), &rhsc);
          else if (code == BIT_AND_EXPR