[SMS] Prevent the creation of reg-moves for non allocatable definition​s (re-submission)

Submitted by Revital Eres on Dec. 21, 2011, 11:59 a.m.

Details

Message ID CAHz1=dVFduUB0vJ9+5tMGWqZRij-V6ZFvLDkEKDJKi9J3mybJw@mail.gmail.com
State New
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Commit Message

Revital Eres Dec. 21, 2011, 11:59 a.m.
Hello,

Following Richard's comment
http://gcc.gnu.org/ml/gcc-patches/2011-12/msg01469.html attached is
a new version of the patch to prevent reg-moves for non allocatable definitions.

Currently testing and bootstrap on ppc64-redhat-linux, enabling SMS on
loops with SC 1.

OK for 4.7 once testing completes?

Thanks,
Revital

Changelog:

gcc/
        * ddg.c (def_non_allocatable_p): New function.
        (add_cross_iteration_register_deps): Call it.

testsuite/
         * gcc.dg/sms-11.c: New file.

Patch hide | download patch | download mbox

Index: ddg.c
===================================================================
--- ddg.c	(revision 182479)
+++ ddg.c	(working copy)
@@ -263,6 +263,23 @@  create_ddg_dep_no_link (ddg_ptr g, ddg_n
     add_edge_to_ddg (g, e);
 }
 
+/* Return true if one of the definitions in INSN is not allocatable.
+   Otherwise return false.  */
+static bool
+def_non_allocatable_p (rtx insn)
+{
+  df_ref *def;
+
+  for (def = DF_INSN_DEFS (insn); *def; def++)
+    {
+      enum machine_mode mode = GET_MODE (DF_REF_REG (*def));
+
+      if (!have_regs_of_mode[mode])
+	return true;
+    }
+
+  return false;
+}
 
 /* Given a downwards exposed register def LAST_DEF (which is the last
    definition of that register in the bb), add inter-loop true dependences
@@ -335,7 +352,8 @@  add_cross_iteration_register_deps (ddg_p
           if (DF_REF_ID (last_def) != DF_REF_ID (first_def)
               || !flag_modulo_sched_allow_regmoves
 	      || JUMP_P (use_node->insn)
-              || autoinc_var_is_used_p (DF_REF_INSN (last_def), use_insn))
+              || autoinc_var_is_used_p (DF_REF_INSN (last_def), use_insn)
+	      || def_non_allocatable_p (DF_REF_INSN (last_def)))
             create_ddg_dep_no_link (g, use_node, first_def_node, ANTI_DEP,
                                     REG_DEP, 1);
 
Index: testsuite/gcc.dg/sms-11.c
===================================================================
--- testsuite/gcc.dg/sms-11.c	(revision 0)
+++ testsuite/gcc.dg/sms-11.c	(revision 0)
@@ -0,0 +1,37 @@ 
+/* { dg-do run } */
+/* { dg-options "-O2 -fmodulo-sched -fmodulo-sched-allow-regmoves -fdump-rtl-sms" } */
+
+extern void abort (void);
+
+float out[4][4] = { 6, 6, 7, 5, 6, 7, 5, 5, 6, 4, 4, 4, 6, 2, 3, 4 };
+
+void
+invert (void)
+{
+  int i, j, k = 0, swap;
+  float tmp[4][4] = { 5, 6, 7, 5, 6, 7, 5, 5, 4, 4, 4, 4, 3, 2, 3, 4 };
+
+  for (i = 0; i < 4; i++)
+    {
+      for (j = i + 1; j < 4; j++)
+	if (tmp[j][i] > tmp[i][i])
+	  swap = j;
+
+      if (swap != i)
+	tmp[i][k] = tmp[swap][k];
+    }
+
+  for (i = 0; i < 4; i++)
+    for (j = 0; j < 4; j++)
+      if (tmp[i][j] != out[i][j])
+	abort ();
+}
+
+int
+main ()
+{
+  invert ();
+  return 0;
+}
+
+/* { dg-final { cleanup-rtl-dump "sms" } } */