tree-vn.c (expressions_equal_p): Do not check type equality or compatibility before calling operand_equal_p.

2008-04-17  Richard Guenther  <rguenther@suse.de>

	* tree-vn.c (expressions_equal_p): Do not check type
	equality or compatibility before calling operand_equal_p.
	* fold-const.c (operand_equal_p): Check equivalence of
	integer constants before bailing out due to signedness or
	precision differences.
	* tree-ssa-sccvn.c (copy_reference_ops_from_ref): Ignore
	spurious differences in type qualification.  Ignore types
	for COMPONENT_REFs at all.

	* gcc.dg/tree-ssa/ssa-fre-17.c: New testcase.

From-SVN: r134384

6 files changed, 50 insertions, 7 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 4efd1c0..4a3a4d0 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,14 @@
+2008-04-17  Richard Guenther  <rguenther@suse.de>
+
+	* tree-vn.c (expressions_equal_p): Do not check type
+	equality or compatibility before calling operand_equal_p.
+	* fold-const.c (operand_equal_p): Check equivalence of
+	integer constants before bailing out due to signedness or
+	precision differences.
+	* tree-ssa-sccvn.c (copy_reference_ops_from_ref): Ignore
+	spurious differences in type qualification.  Ignore types
+	for COMPONENT_REFs at all.
+
 2008-04-17  Christian Bruel  <christian.bruel@st.com>
 
 	* config/sh/sh.c (expand_cbranchdi4): Use original operands for
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index c145178..4e46761 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -3026,6 +3026,11 @@ operand_equal_p (const_tree arg0, const_tree arg1, unsigned int flags)
   if (TREE_CODE (arg0) == ERROR_MARK || TREE_CODE (arg1) == ERROR_MARK)
     return 0;
 
+  /* Check equality of integer constants before bailing out due to
+     precision differences.  */
+  if (TREE_CODE (arg0) == INTEGER_CST && TREE_CODE (arg1) == INTEGER_CST)
+    return tree_int_cst_equal (arg0, arg1);
+
   /* If both types don't have the same signedness, then we can't consider
      them equal.  We must check this before the STRIP_NOPS calls
      because they may change the signedness of the arguments.  */
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 88c24ec..3723bcf 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2008-04-17  Richard Guenther  <rguenther@suse.de>
+
+	* gcc.dg/tree-ssa/ssa-fre-17.c: New testcase.
+
 2008-04-17  Christian Bruel  <christian.bruel@st.com>
 
 	* gcc.dg/long-long-compare-1.c: New testcase. 
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-17.c b/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-17.c
new file mode 100644
index 0000000..aced649
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-17.c
@@ -0,0 +1,23 @@
+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-fre-details -fno-tree-sra" } */
+
+struct Bar {
+  int dom;
+};
+struct Foo {
+  struct Bar doms[3];
+};
+
+int foo(int i, int j, int k)
+{
+  struct Foo f;
+
+  f.doms[0].dom = i;
+  f.doms[1].dom = j;
+  f.doms[2].dom = k;
+  return f.doms[0LL].dom;
+}
+
+/* { dg-final { scan-tree-dump "Replaced f.doms\\\[0\\\].dom with i_" "fre" } } */
+/* { dg-final { cleanup-tree-dump "fre" } } */
+
diff --git a/gcc/tree-ssa-sccvn.c b/gcc/tree-ssa-sccvn.c
index 849eade..6fc0840 100644
--- a/gcc/tree-ssa-sccvn.c
+++ b/gcc/tree-ssa-sccvn.c
@@ -511,7 +511,8 @@ copy_reference_ops_from_ref (tree ref, VEC(vn_reference_op_s, heap) **result)
       vn_reference_op_s temp;
 
       memset (&temp, 0, sizeof (temp));
-      temp.type = TREE_TYPE (ref);
+      /* We do not care for spurious type qualifications.  */
+      temp.type = TYPE_MAIN_VARIANT (TREE_TYPE (ref));
       temp.opcode = TREE_CODE (ref);
 
       switch (temp.opcode)
@@ -528,6 +529,10 @@ copy_reference_ops_from_ref (tree ref, VEC(vn_reference_op_s, heap) **result)
 	  temp.op1 = TREE_OPERAND (ref, 2);
 	  break;
 	case COMPONENT_REF:
+	  /* The field decl is enough to unambiguously specify the field,
+	     a matching type is not necessary and a mismatching type
+	     is always a spurious difference.  */
+	  temp.type = NULL_TREE;
 	  /* If this is a reference to a union member, record the union
 	     member size as operand.  Do so only if we are doing
 	     expression insertion (during FRE), as PRE currently gets
@@ -536,10 +541,7 @@ copy_reference_ops_from_ref (tree ref, VEC(vn_reference_op_s, heap) **result)
 	      && TREE_CODE (DECL_CONTEXT (TREE_OPERAND (ref, 1))) == UNION_TYPE
 	      && integer_zerop (DECL_FIELD_OFFSET (TREE_OPERAND (ref, 1)))
 	      && integer_zerop (DECL_FIELD_BIT_OFFSET (TREE_OPERAND (ref, 1))))
-	    {
-	      temp.type = NULL_TREE;
-	      temp.op0 = TYPE_SIZE (TREE_TYPE (TREE_OPERAND (ref, 1)));
-	    }
+	    temp.op0 = TYPE_SIZE (TREE_TYPE (TREE_OPERAND (ref, 1)));
 	  else
 	    /* Record field as operand.  */
 	    temp.op0 = TREE_OPERAND (ref, 1);
diff --git a/gcc/tree-vn.c b/gcc/tree-vn.c
index c09dfb7..40efea6 100644
--- a/gcc/tree-vn.c
+++ b/gcc/tree-vn.c
@@ -83,8 +83,6 @@ expressions_equal_p (tree e1, tree e2)
 
     }
   else if (TREE_CODE (e1) == TREE_CODE (e2)
-	   && (te1 == te2
-	       || types_compatible_p (te1, te2))
 	   && operand_equal_p (e1, e2, OEP_PURE_SAME))
     return true;