Disallow pointer operands for |, ^ and partly & [PR106878]

My change to match.pd (that added the two simplifications this patch
touches) results in more |/^/& assignments with pointer arguments,
but since r12-1608 we reject pointer operands for BIT_NOT_EXPR.

Disallowing them for BIT_NOT_EXPR and allowing for BIT_{IOR,XOR,AND}_EXPR
leads to a match.pd maintainance nightmare (see one of the patches in the
PR), so either we want to allow pointer operand on BIT_NOT_EXPR (but then
we run into issues e.g. with the ranger which expects it can emulate
BIT_NOT_EXPR ~X as - 1 - X which doesn't work for pointers which don't
support MINUS_EXPR), or the following patch disallows pointer arguments
for all of BIT_{IOR,XOR,AND}_EXPR with the exception of BIT_AND_EXPR
with INTEGER_CST last operand (for simpler pointer realignment).
I had to tweak one reassoc optimization and the two match.pd
simplifications.

2022-09-14  Jakub Jelinek  <jakub@redhat.com>

	PR tree-optimization/106878
	* tree-cfg.cc (verify_gimple_assign_binary): Disallow pointer,
	reference or OFFSET_TYPE BIT_IOR_EXPR, BIT_XOR_EXPR or, unless
	the second argument is INTEGER_CST, BIT_AND_EXPR.
	* match.pd ((type) X op CST -> (type) (X op ((type-x) CST)),
	(type) (((type2) X) op Y) -> (X op (type) Y)): Punt for
	POINTER_TYPE_P or OFFSET_TYPE.
	* tree-ssa-reassoc.cc (optimize_range_tests_cmp_bitwise): For
	pointers cast them to pointer sized integers first.

	* gcc.c-torture/compile/pr106878.c: New test.

diff --git a/gcc/match.pd b/gcc/match.pd
index 17318f523fb6dfd59fb91e18532246f4b8f1c858..345bcb701a5b8dcf8dbfa66f1126aed63b65ae04 100644 (file)
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -1763,6 +1763,8 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
         && (int_fits_type_p (@1, TREE_TYPE (@0))
             || tree_nop_conversion_p (TREE_TYPE (@0), type)))
        || types_match (@0, @1))
+       && !POINTER_TYPE_P (TREE_TYPE (@0))
+       && TREE_CODE (TREE_TYPE (@0)) != OFFSET_TYPE
        /* ???  This transform conflicts with fold-const.cc doing
          Convert (T)(x & c) into (T)x & (T)c, if c is an integer
          constants (if x has signed type, the sign bit cannot be set
@@ -1799,7 +1801,9 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
   (if (GIMPLE
        && TREE_CODE (@1) != INTEGER_CST
        && tree_nop_conversion_p (type, TREE_TYPE (@2))
-       && types_match (type, @0))
+       && types_match (type, @0)
+       && !POINTER_TYPE_P (TREE_TYPE (@0))
+       && TREE_CODE (TREE_TYPE (@0)) != OFFSET_TYPE)
    (bitop @0 (convert @1)))))
 
 (for bitop (bit_and bit_ior)

diff --git a/gcc/testsuite/gcc.c-torture/compile/pr106878.c b/gcc/testsuite/gcc.c-torture/compile/pr106878.c
new file mode 100644 (file)
index 0000000..c845718
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr106878.c
@@ -0,0 +1,15 @@
+/* PR tree-optimization/106878 */
+
+typedef __INTPTR_TYPE__ intptr_t;
+typedef __UINTPTR_TYPE__ uintptr_t;
+int a;
+
+int
+foo (const int *c)
+{
+  uintptr_t d = ((intptr_t) c | (intptr_t) &a) & 65535 << 16;
+  intptr_t e = (intptr_t) c;
+  if (d != (e & 65535 << 16))
+    return 1;
+  return 0;
+}

diff --git a/gcc/tree-cfg.cc b/gcc/tree-cfg.cc
index e39d9471220d220adad961cedda346b5d6d51c10..41ce1b29d177639783a751ae96d3624aa3496a98 100644 (file)
--- a/gcc/tree-cfg.cc
+++ b/gcc/tree-cfg.cc
@@ -4167,6 +4167,8 @@ verify_gimple_assign_binary (gassign *stmt)
     case ROUND_MOD_EXPR:
     case RDIV_EXPR:
     case EXACT_DIV_EXPR:
+    case BIT_IOR_EXPR:
+    case BIT_XOR_EXPR:
       /* Disallow pointer and offset types for many of the binary gimple. */
       if (POINTER_TYPE_P (lhs_type)
          || TREE_CODE (lhs_type) == OFFSET_TYPE)
@@ -4182,9 +4184,23 @@ verify_gimple_assign_binary (gassign *stmt)
 
     case MIN_EXPR:
     case MAX_EXPR:
-    case BIT_IOR_EXPR:
-    case BIT_XOR_EXPR:
+      /* Continue with generic binary expression handling.  */
+      break;
+
     case BIT_AND_EXPR:
+      if (POINTER_TYPE_P (lhs_type)
+         && TREE_CODE (rhs2) == INTEGER_CST)
+       break;
+      /* Disallow pointer and offset types for many of the binary gimple. */
+      if (POINTER_TYPE_P (lhs_type)
+         || TREE_CODE (lhs_type) == OFFSET_TYPE)
+       {
+         error ("invalid types for %qs", code_name);
+         debug_generic_expr (lhs_type);
+         debug_generic_expr (rhs1_type);
+         debug_generic_expr (rhs2_type);
+         return true;
+       }
       /* Continue with generic binary expression handling.  */
       break;
 

diff --git a/gcc/tree-ssa-reassoc.cc b/gcc/tree-ssa-reassoc.cc
index e13e2cb308d4b23e8a65a9c2dcc368d47f102749..f45e552a8ccb1bd5483af02acca3ae1b10507503 100644 (file)
--- a/gcc/tree-ssa-reassoc.cc
+++ b/gcc/tree-ssa-reassoc.cc
@@ -3608,10 +3608,14 @@ optimize_range_tests_cmp_bitwise (enum tree_code opcode, int first, int length,
        tree type2 = NULL_TREE;
        bool strict_overflow_p = false;
        candidates.truncate (0);
+       if (POINTER_TYPE_P (type1))
+         type1 = pointer_sized_int_node;
        for (j = i; j; j = chains[j - 1])
          {
            tree type = TREE_TYPE (ranges[j - 1].exp);
            strict_overflow_p |= ranges[j - 1].strict_overflow_p;
+           if (POINTER_TYPE_P (type))
+             type = pointer_sized_int_node;
            if ((b % 4) == 3)
              {
                /* For the signed < 0 cases, the types should be
@@ -3642,6 +3646,8 @@ optimize_range_tests_cmp_bitwise (enum tree_code opcode, int first, int length,
            tree type = TREE_TYPE (ranges[j - 1].exp);
            if (j == k)
              continue;
+           if (POINTER_TYPE_P (type))
+             type = pointer_sized_int_node;
            if ((b % 4) == 3)
              {
                if (!useless_type_conversion_p (type1, type))
@@ -3671,7 +3677,7 @@ optimize_range_tests_cmp_bitwise (enum tree_code opcode, int first, int length,
                op = r->exp;
                continue;
              }
-           if (id == l)
+           if (id == l || POINTER_TYPE_P (TREE_TYPE (op)))
              {
                code = (b % 4) == 3 ? BIT_NOT_EXPR : NOP_EXPR;
                g = gimple_build_assign (make_ssa_name (type1), code, op);
@@ -3695,6 +3701,14 @@ optimize_range_tests_cmp_bitwise (enum tree_code opcode, int first, int length,
            gimple_seq_add_stmt_without_update (&seq, g);
            op = gimple_assign_lhs (g);
          }
+       type1 = TREE_TYPE (ranges[k - 1].exp);
+       if (POINTER_TYPE_P (type1))
+         {
+           gimple *g
+             = gimple_build_assign (make_ssa_name (type1), NOP_EXPR, op);
+           gimple_seq_add_stmt_without_update (&seq, g);
+           op = gimple_assign_lhs (g);
+         }
        candidates.pop ();
        if (update_range_test (&ranges[k - 1], NULL, candidates.address (),
                               candidates.length (), opcode, ops, op,