Verify that last argument of __builtin_expect_with_probability is a real cst (PR c/87811).

2018-11-05  Martin Liska  <mliska@suse.cz>

	PR c/87811
	* predict.c (expr_expected_value_1): Verify
	that last argument is a real constants and emit
	error.
2018-11-05  Martin Liska  <mliska@suse.cz>

	PR c/87811
	* gcc.dg/pr87811.c: New test.
	* gcc.dg/pr87811-2.c: Likewise.
	* gcc.dg/pr87811-3.c: Likewise.
2018-11-05  Martin Liska  <mliska@suse.cz>

	PR c/87811
	* doc/extend.texi: Update constrain about the last argument
	of __builtin_expect_with_probability.

From-SVN: r265785

gcc/ChangeLog

 2018-11-05  Martin Liska  <mliska@suse.cz>
 
+	PR c/87811
+	* doc/extend.texi: Update constrain about the last argument
+	of __builtin_expect_with_probability.
+
+2018-11-05  Martin Liska  <mliska@suse.cz>
+
+	PR c/87811
+	* predict.c (expr_expected_value_1): Verify
+	that last argument is a real constants and emit
+	error.
+
+2018-11-05  Martin Liska  <mliska@suse.cz>
+
 	PR gcov-profile/77698
 	* ipa-profile.c (ipa_profile): Adjust hotness threshold
 	only in LTO mode.

gcc/doc/extend.texi

@@ -12046,7 +12046,8 @@ when testing pointer or floating-point values.
 This function has the same semantics as @code{__builtin_expect},
 but the caller provides the expected probability that @var{exp} == @var{c}.
 The last argument, @var{probability}, is a floating-point value in the
-range 0.0 to 1.0, inclusive.
+range 0.0 to 1.0, inclusive.  The @var{probability} argument must be
+a compiler time constant.
 @end deftypefn
 
 @deftypefn {Built-in Function} void __builtin_trap (void)

gcc/predict.c

@@ -2467,6 +2467,13 @@ expr_expected_value_1 (tree type, tree op0, enum tree_code code,
 		  base = build_real_from_int_cst (t, base);
 		  tree r = fold_build2_initializer_loc (UNKNOWN_LOCATION,
 							MULT_EXPR, t, prob, base);
+		  if (TREE_CODE (r) != REAL_CST)
+		    {
+		      error_at (gimple_location (def),
+				"probability argument %qE must be a compile "
+				"time constant", prob);
+		      return NULL;
+		    }
 		  HOST_WIDE_INT probi
 		    = real_to_integer (TREE_REAL_CST_PTR (r));
 		  if (probi >= 0 && probi <= REG_BR_PROB_BASE)
@@ -2474,6 +2481,11 @@ expr_expected_value_1 (tree type, tree op0, enum tree_code code,
 		      *predictor = PRED_BUILTIN_EXPECT_WITH_PROBABILITY;
 		      *probability = probi;
 		    }
+		  else
+		    error_at (gimple_location (def),
+			      "probability argument %qE must be a in the "
+			      "range 0.0 to 1.0", prob);
+
 		  return gimple_call_arg (def, 1);
 		}
 

gcc/testsuite/ChangeLog

 2018-11-05  Martin Liska  <mliska@suse.cz>
 
+	PR c/87811
+	* gcc.dg/pr87811.c: New test.
+	* gcc.dg/pr87811-2.c: Likewise.
+	* gcc.dg/pr87811-3.c: Likewise.
+
+2018-11-05  Martin Liska  <mliska@suse.cz>
+
 	PR gcov-profile/77698
 	* gcc.dg/tree-prof/pr77698.c: New test.
 

gcc/testsuite/gcc.dg/pr87811-2.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-profile_estimate" } */
+
+void bar (void);
+
+void
+foo (int i)
+{
+  if (__builtin_expect_with_probability (i, 0, 2.0f)) /* { dg-error "probability argument .* must be a in the range 0\\\.0 to 1\\\.0" } */
+    bar ();
+}
+
+/* { dg-final { scan-tree-dump-not "__builtin_expect_with_probability heuristics of edge" "profile_estimate"} } */

gcc/testsuite/gcc.dg/pr87811-3.c

+/* { dg-do compile } */
+/* { dg-options "-fdump-tree-profile_estimate" } */
+
+void bar (void);
+
+void
+foo (int i)
+{
+  if (__builtin_expect_with_probability (i, 0, 2.0f))
+    bar ();
+}

gcc/testsuite/gcc.dg/pr87811.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-profile_estimate" } */
+
+void bar (void);
+
+void
+foo (int i, double d)
+{
+  if (__builtin_expect_with_probability (i, 0, d)) /* { dg-error "probability argument .d. must be a compile time constant" } */
+    bar ();
+}
+
+/* { dg-final { scan-tree-dump-not "__builtin_expect_with_probability heuristics of edge" "profile_estimate"} } */