PR tree-optimization/51600

	* ipa-inline-analysis.c (estimate_edge_devirt_benefit): Disable code
	that benefits small functions.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@182984 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index cbe134f..f5cfe23 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,15 @@
 2012-01-07  Jan Hubicka  <jh@suse.cz>
 
+       PR tree-optimization/51600
+       * ipa-inline-analysis.c (estimate_edge_devirt_benefit): Disable code
+       that benefits small functions.
+
+2012-01-07  Jan Hubicka  <jh@suse.cz>
+
+       * ipa-inline.c (want_inline_small_function_p): Fix formating.
+
+2012-01-07  Jan Hubicka  <jh@suse.cz>
+
        PR tree-optimization/51680
        * ipa-inline.c (want_inline_small_function_p): Be more lax on functions
        whose inlining reduce unit size.

diff --git a/gcc/ipa-inline-analysis.c b/gcc/ipa-inline-analysis.c
index 0652e64..5778e68 100644 (file)
--- a/gcc/ipa-inline-analysis.c
+++ b/gcc/ipa-inline-analysis.c
@@ -2202,11 +2202,9 @@ estimate_edge_devirt_benefit (struct cgraph_edge *ie,
                              VEC (tree, heap) *known_binfos)
 {
   tree target;
-  struct cgraph_node *callee;
-  struct inline_summary *isummary;
-  int edge_size = 0, edge_time = 0;
+  int time_diff, size_diff;
 
-  if (!known_vals || !known_binfos)
+  if (!known_vals && !known_binfos)
     return;
 
   target = ipa_get_indirect_edge_target (ie, known_vals, known_binfos);
@@ -2214,10 +2212,22 @@ estimate_edge_devirt_benefit (struct cgraph_edge *ie,
     return;
 
   /* Account for difference in cost between indirect and direct calls.  */
-  *size -= ((eni_size_weights.indirect_call_cost - eni_size_weights.call_cost)
-           * INLINE_SIZE_SCALE);
-  *time -= ((eni_time_weights.indirect_call_cost - eni_time_weights.call_cost)
-           * INLINE_TIME_SCALE * prob / REG_BR_PROB_BASE);
+  size_diff = ((eni_size_weights.indirect_call_cost - eni_size_weights.call_cost)
+               * INLINE_SIZE_SCALE);
+  *size -= size_diff;
+  time_diff = ((eni_time_weights.indirect_call_cost - eni_time_weights.call_cost)
+              * INLINE_TIME_SCALE * prob / REG_BR_PROB_BASE);
+  *time -= time_diff;
+
+  /* TODO: This code is trying to benefit indirect calls that will be inlined later.
+     The logic however do not belong into local size/time estimates and can not be
+     done here, or the accounting of changes will get wrong and we result with 
+     negative function body sizes.  We need to introduce infrastructure for independent
+     benefits to the inliner.  */
+#if 0
+  struct cgraph_node *callee;
+  struct inline_summary *isummary;
+  int edge_size, edge_time, time_diff, size_diff;
 
   callee = cgraph_get_node (target);
   if (!callee || !callee->analyzed)
@@ -2229,22 +2239,20 @@ estimate_edge_devirt_benefit (struct cgraph_edge *ie,
   estimate_edge_size_and_time (ie, &edge_size, &edge_time, prob);
 
   /* Count benefit only from functions that definitely will be inlined
-     if additional context from NODE's caller were available.  */
-  if (edge_size >= isummary->size * INLINE_SIZE_SCALE)
+     if additional context from NODE's caller were available. 
+
+     We just account overall size change by inlining.  TODO:
+     we really need to add sort of benefit metrics for these kind of
+     cases. */
+  if (edge_size - size_diff >= isummary->size * INLINE_SIZE_SCALE)
     {
       /* Subtract size and time that we added for edge IE.  */
-      *size -= edge_size;
-      *time -= edge_time;
-
-      /* Subtract benefit from inlining devirtualized call.  */
-      *size -= edge_size - isummary->size * INLINE_SIZE_SCALE;
-      *time -= edge_time - (isummary->time * INLINE_TIME_SCALE * prob
-                           / REG_BR_PROB_BASE);
+      *size -= edge_size - size_diff;
 
-      /* TODO: estimate benefit from optimizing CALLEE's body provided
-        additional context from IE call site.
-        For insipiration see ipa-cp.c: devirtualization_time_bonus().  */
+      /* Account inlined call.  */
+      *size += isummary->size * INLINE_SIZE_SCALE;
     }
+#endif
 }
 
 

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 02de55e..3385000 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2012-01-07  Jan Hubicka  <jh@suse.cz>
+
+       PR tree-optimization/51600
+       * g++.dg/torture/pr51600.C: New testcase.
+
 2012-01-07  John David Anglin  <dave.anglin@nrc-cnrc.gc.ca>
 
        PR gcov-profile/51715

diff --git a/gcc/testsuite/g++.dg/torture/pr51600.C b/gcc/testsuite/g++.dg/torture/pr51600.C
new file mode 100644 (file)
index 0000000..6180360
--- /dev/null
+++ b/gcc/testsuite/g++.dg/torture/pr51600.C
@@ -0,0 +1,16 @@
+template<class T> inline T min(T a, T b) { return a < b ? a : b; }
+double cornerbound(double *P, double (*m)(double, double))
+{
+  double b=m(P[0],P[3]);
+  return m(b,P[12]);
+}
+void bound(double *P, double (*m)(double, double), double b)
+{
+  m(b,cornerbound(P,m));
+}
+void bounds(double fuzz, unsigned maxdepth)
+{
+  double Px[]={};
+  double bx=Px[0];
+  bound(Px,min,bx);
+}