diff mbox

[07/16] fold-const.c: add selftests

Message ID 1464901625-54547-8-git-send-email-dmalcolm@redhat.com
State New
Headers show

Commit Message

David Malcolm June 2, 2016, 9:06 p.m. UTC 
Jeff approved an older version of this (as a separate
unittests/test-folding.c):
https://gcc.gnu.org/ml/gcc-patches/2015-10/msg03305.html
> OK if/when prereqs are approved. Minor twiddling if we end up
> moving it elsewhere or standardizing/reducing header files
> is pre-approved.

gcc/ChangeLog:
	* fold-const.c: Include "selftest.h".
	(assert_binop_folds_to_const): New function.
	(assert_binop_folds_to_nonlvalue): New function.
	(test_arithmetic_folding): New function.
	(selftest::fold_const_c_tests): New function.
---
 gcc/fold-const.c | 75 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 75 insertions(+)
diff mbox

Patch

diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 8a7c93e..dd8cdab 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -76,6 +76,7 @@  along with GCC; see the file COPYING3.  If not see
 #include "case-cfn-macros.h"
 #include "stringpool.h"
 #include "tree-ssanames.h"
+#include "selftest.h"
 
 #ifndef LOAD_EXTEND_OP
 #define LOAD_EXTEND_OP(M) UNKNOWN
@@ -14455,3 +14456,77 @@  c_getstr (tree src)
 
   return TREE_STRING_POINTER (src) + tree_to_uhwi (offset_node);
 }
+
+#if CHECKING_P
+
+/* Helper functions for writing tests of folding trees.  */
+
+/* Verify that the binary op (LHS CODE RHS) folds to CONSTANT.  */
+
+static void
+assert_binop_folds_to_const (tree lhs, enum tree_code code, tree rhs,
+			     tree constant)
+{
+  ASSERT_EQ (constant, fold_build2 (code, TREE_TYPE (lhs), lhs, rhs));
+}
+
+/* Verify that the binary op (LHS CODE RHS) folds to an NON_LVALUE_EXPR
+   wrapping WRAPPED_EXPR.  */
+
+static void
+assert_binop_folds_to_nonlvalue (tree lhs, enum tree_code code, tree rhs,
+				 tree wrapped_expr)
+{
+  tree result = fold_build2 (code, TREE_TYPE (lhs), lhs, rhs);
+  ASSERT_NE (wrapped_expr, result);
+  ASSERT_EQ (NON_LVALUE_EXPR, TREE_CODE (result));
+  ASSERT_EQ (wrapped_expr, TREE_OPERAND (result, 0));
+}
+
+static void
+test_arithmetic_folding ()
+{
+  tree type = integer_type_node;
+  tree x = create_tmp_var_raw (type, "x");
+  tree zero = build_zero_cst (type);
+  tree one = build_int_cst (type, 1);
+
+  /* Addition.  */
+  /* 1 <-- (0 + 1) */
+  assert_binop_folds_to_const (zero, PLUS_EXPR, one,
+			       one);
+  assert_binop_folds_to_const (one, PLUS_EXPR, zero,
+			       one);
+
+  /* (nonlvalue)x <-- (x + 0) */
+  assert_binop_folds_to_nonlvalue (x, PLUS_EXPR, zero,
+				   x);
+
+  /* Subtraction.  */
+  /* 0 <-- (x - x) */
+  assert_binop_folds_to_const (x, MINUS_EXPR, x,
+			       zero);
+  assert_binop_folds_to_nonlvalue (x, MINUS_EXPR, zero,
+				   x);
+
+  /* Multiplication.  */
+  /* 0 <-- (x * 0) */
+  assert_binop_folds_to_const (x, MULT_EXPR, zero,
+			       zero);
+
+  /* (nonlvalue)x <-- (x * 1) */
+  assert_binop_folds_to_nonlvalue (x, MULT_EXPR, one,
+				   x);
+}
+
+namespace selftest {
+
+void
+fold_const_c_tests ()
+{
+  test_arithmetic_folding ();
+}
+
+} // namespace selftest
+
+#endif /* CHECKING_P */