Use is_xcoff_format in gas testsuite

[Alan Modra]

	* testsuite/gas/all/gas.exp: Use is_xcoff_format.
	* testsuite/gas/ppc/ppc.exp: Likewise.
	* testsuite/gas/all/weakref1l.d: Likewise.

diff --git a/gas/testsuite/gas/all/gas.exp b/gas/testsuite/gas/all/gas.exp
index c782955370..5496d0bf7a 100644
--- a/gas/testsuite/gas/all/gas.exp
+++ b/gas/testsuite/gas/all/gas.exp
@@ -161,7 +161,9 @@ switch -glob $target_triplet {
 	setup_xfail "m68hc1*-*-*" "m6811-*-*" "m6812-*-*" "rl78-*-*"
 	setup_xfail "riscv*-*-*" "rx-*-*" "vax*-*-*" "xgate*-*-*" "z8k-*-*"
 	# rs6000-aix disallows redefinition via .comm.
-	setup_xfail "*-*-aix*"
+	if [is_xcoff_format] {
+	    setup_xfail *-*-*
+	}
 	# These targets fail redef3 because section contents for the
 	# word referencing the .comm sym is not zero and/or its reloc
 	# has a non-zero addend.  Relaxing the test would hide real
diff --git a/gas/testsuite/gas/all/weakref1l.d b/gas/testsuite/gas/all/weakref1l.d
index 4172e4c0c9..3a42c00a8f 100644
--- a/gas/testsuite/gas/all/weakref1l.d
+++ b/gas/testsuite/gas/all/weakref1l.d
@@ -3,7 +3,7 @@
 #source: weakref1.s
 # aix drops local symbols
 # see weakref1.d for comments on the other notargets
-#notarget: *-*-aix* alpha*-*-osf* *-*-ecoff pdp11-*-aout
+#notarget: [is_xcoff_format] alpha*-*-osf* *-*-ecoff pdp11-*-aout
 
 # the rest of this file is generated with the following script:
 # # script begin
diff --git a/gas/testsuite/gas/ppc/ppc.exp b/gas/testsuite/gas/ppc/ppc.exp
index 48c4ce62f3..4fb06618a3 100644
--- a/gas/testsuite/gas/ppc/ppc.exp
+++ b/gas/testsuite/gas/ppc/ppc.exp
@@ -44,9 +44,7 @@ run_dump_test "altivec_and_spe"
 run_list_test "range" "-a32"
 run_dump_test "cell"
 
-if { [istarget "*-*-aix*"]
-     || [istarget "*-*-macos*"]
-     || [istarget "*-*-beos*"] } then {
+if { [is_xcoff_format] } then {
     run_dump_test "test1xcoff32"
     run_dump_test "test2xcoff32"
     run_dump_test "altivec_xcoff"

-- 
Alan Modra
Australia Development Lab, IBM