2013-08-28 Dehao Chen <dehao@google.com>

	* ipa-inline.c (edge_badness): Fix integer underflow.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@202059 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 24 insertions, 5 deletions

diff --git a/gcc/ipa-inline.c b/gcc/ipa-inline.c
index 2cdf87519c5..11526957190 100644
--- a/gcc/ipa-inline.c
+++ b/gcc/ipa-inline.c
@@ -113,10 +113,12 @@ along with GCC; see the file COPYING3.  If not see
 #include "target.h"
 #include "ipa-inline.h"
 #include "ipa-utils.h"
+#include "sreal.h"
 
 /* Statistics we collect about inlining algorithm.  */
 static int overall_size;
 static gcov_type max_count;
+static sreal max_count_real, max_relbenefit_real, half_int_min_real;
 
 /* Return false when inlining edge E would lead to violating
    limits on function unit growth or stack usage growth.  
@@ -891,12 +893,26 @@ edge_badness (struct cgraph_edge *edge, bool dump)
 
   else if (max_count)
     {
+      sreal tmp, relbenefit_real, growth_real;
       int relbenefit = relative_time_benefit (callee_info, edge, edge_time);
-      badness =
-	((int)
-	 ((double) edge->count * INT_MIN / 2 / max_count / RELATIVE_TIME_BENEFIT_RANGE) *
-	 relbenefit) / growth;
-      
+
+      sreal_init(&relbenefit_real, relbenefit, 0);
+      sreal_init(&growth_real, growth, 0);
+
+      /* relative_edge_count.  */
+      sreal_init (&tmp, edge->count, 0);
+      sreal_div (&tmp, &tmp, &max_count_real);
+
+      /* relative_time_benefit.  */
+      sreal_mul (&tmp, &tmp, &relbenefit_real);
+      sreal_div (&tmp, &tmp, &max_relbenefit_real);
+
+      /* growth_f_caller.  */
+      sreal_mul (&tmp, &tmp, &half_int_min_real);
+      sreal_div (&tmp, &tmp, &growth_real);
+
+      badness = -1 * sreal_to_int (&tmp);
+ 
       /* Be sure that insanity of the profile won't lead to increasing counts
 	 in the scalling and thus to overflow in the computation above.  */
       gcc_assert (max_count >= edge->count);
@@ -1542,6 +1558,9 @@ inline_small_functions (void)
 	  if (max_count < edge->count)
 	    max_count = edge->count;
       }
+  sreal_init (&max_count_real, max_count, 0);
+  sreal_init (&max_relbenefit_real, RELATIVE_TIME_BENEFIT_RANGE, 0);
+  sreal_init (&half_int_min_real, INT_MAX / 2, 0);
   ipa_free_postorder_info ();
   initialize_growth_caches ();