From: Evgeny Stupachenko <evstupac@gmail.com>
Date: Thu, 17 Apr 2014 07:47:37 +0000 (+0000)
Subject: i386.c (x86_add_stmt_cost): Fix vector cost model for Silvermont.
X-Git-Tag: releases/gcc-5.1.0~8070
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=170c1776c45f875d346519a06514d510b0905fa8;p=thirdparty%2Fgcc.git

i386.c (x86_add_stmt_cost): Fix vector cost model for Silvermont.

gcc/
        * config/i386/i386.c (x86_add_stmt_cost): Fix vector cost model for
        Silvermont.

From-SVN: r209466
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index c6fa5c08e5a0..320e15ab2899 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2014-04-17  Evgeny Stupachenko  <evstupac@gmail.com>
+
+	* config/i386/i386.c (x86_add_stmt_cost): Fix vector cost model for
+	Silvermont.
+
 2014-04-17  Evgeny Stupachenko  <evstupac@gmail.com>
 
 	* config/i386/x86-tune.def (TARGET_SLOW_PSHUFB): New tune definition.
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 0ae3cdaf6cea..88142a8cf156 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -81,6 +81,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "context.h"
 #include "pass_manager.h"
 #include "target-globals.h"
+#include "tree-vectorizer.h"
 
 static rtx legitimize_dllimport_symbol (rtx, bool);
 static rtx legitimize_pe_coff_extern_decl (rtx, bool);
@@ -46329,6 +46330,18 @@ ix86_add_stmt_cost (void *data, int count, enum vect_cost_for_stmt kind,
     count *= 50;  /* FIXME.  */
 
   retval = (unsigned) (count * stmt_cost);
+
+  /* We need to multiply all vector stmt cost by 1.7 (estimated cost)
+     for Silvermont as it has out of order integer pipeline and can execute
+     2 scalar instruction per tick, but has in order SIMD pipeline.  */
+  if (TARGET_SILVERMONT || TARGET_INTEL)
+    if (stmt_info && stmt_info->stmt)
+      {
+	tree lhs_op = gimple_get_lhs (stmt_info->stmt);
+	if (lhs_op && TREE_CODE (TREE_TYPE (lhs_op)) == INTEGER_TYPE)
+	  retval = (retval * 17) / 10;
+      }
+
   cost[where] += retval;
 
   return retval;