re PR tree-optimization/84232 (gcc.dg/tree-ssa/ssa-dom-cse-2.c fail with -march=silvermont)

	PR tree-optimization/84232
	* gcc.dg/tree-ssa/ssa-dom-cse-2.c: Add -mtune-generic on x86.

From-SVN: r257516

gcc/testsuite/ChangeLog

 2018-02-09  Jakub Jelinek  <jakub@redhat.com>
 
+	PR tree-optimization/84232
+	* gcc.dg/tree-ssa/ssa-dom-cse-2.c: Add -mtune-generic on x86.
+
 	PR debug/84252
 	* gcc.target/aarch64/pr84252.c: New test.
 

gcc/testsuite/gcc.dg/tree-ssa/ssa-dom-cse-2.c

@@ -2,8 +2,10 @@
 /* { dg-options "-O3 -fno-tree-fre -fno-tree-pre -fdump-tree-optimized --param sra-max-scalarization-size-Ospeed=32" } */
 /* System Z needs hardware vector support for this to work (the optimization
    gets too complex without it.
-   { dg-additional-options "-march=z13" { target { s390x-*-* } } } */
-
+   { dg-additional-options "-march=z13" { target s390x-*-* } } */
+/* Use generic tuning on x86 for the same reasons as why alpha, powerpc etc. are
+   xfailed below.
+   { dg-additional-options "-mtune=generic" { target i?86-*-* x86_64-*-* } } */
 
 int
 foo ()