[PATCH 5/8] gdbserver/s390: Switch on tracepoint support.

["Marcin Kościelnicki" <koriakin@0x04.net>]

Also adds s390 support to gdb.trace testsuite.

gdb/gdbserver/ChangeLog:

	* linux-s390-low.c (s390_supports_tracepoints): New function.
	(struct linux_target_ops): Fill supports_tracepoints hook.

gdb/testsuite/ChangeLog:

	* gdb.trace/ftrace.exp: Select $r2 as test register for s390.
	* gdb.trace/mi-trace-frame-collected.exp: Expect 2 registers on s390.
	* gdb.trace/trace-common.h (x86_trace_dummy): Add s390 fast tracepoint
	placeholder.
	* lib/trace-support.exp: Add s390 registers.
---
 gdb/gdbserver/ChangeLog                              |  5 +++++
 gdb/gdbserver/linux-s390-low.c                       |  8 +++++++-
 gdb/testsuite/ChangeLog                              |  8 ++++++++
 gdb/testsuite/gdb.trace/ftrace.exp                   |  2 ++
 gdb/testsuite/gdb.trace/mi-trace-frame-collected.exp | 14 +++++++++++---
 gdb/testsuite/gdb.trace/trace-common.h               |  8 ++++++++
 gdb/testsuite/lib/trace-support.exp                  |  4 ++++
 7 files changed, 45 insertions(+), 4 deletions(-)

diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog
index 5e47b46..e0d8c67 100644
--- a/gdb/gdbserver/ChangeLog
+++ b/gdb/gdbserver/ChangeLog
@@ -1,3 +1,8 @@
+2016-01-24  Marcin Kościelnicki  <koriakin@0x04.net>
+
+	* linux-s390-low.c (s390_supports_tracepoints): New function.
+	(struct linux_target_ops): Fill supports_tracepoints hook.
+
 2016-01-21  Marcin Kościelnicki  <koriakin@0x04.net>
 
 	* linux-s390-low.c (s390_supports_z_point_type): New function.
diff --git a/gdb/gdbserver/linux-s390-low.c b/gdb/gdbserver/linux-s390-low.c
index 420430b..ab3e62b 100644
--- a/gdb/gdbserver/linux-s390-low.c
+++ b/gdb/gdbserver/linux-s390-low.c
@@ -688,6 +688,12 @@ s390_regs_info (void)
   return &regs_info;
 }
 
+static int
+s390_supports_tracepoints (void)
+{
+  return 1;
+}
+
 struct linux_target_ops the_low_target = {
   s390_arch_setup,
   s390_regs_info,
@@ -714,7 +720,7 @@ struct linux_target_ops the_low_target = {
   NULL, /* new_fork */
   NULL, /* prepare_to_resume */
   NULL, /* process_qsupported */
-  NULL, /* supports_tracepoints */
+  s390_supports_tracepoints,
   NULL, /* get_thread_area */
   NULL, /* install_fast_tracepoint_jump_pad */
   NULL, /* emit_ops */
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index a201b66..98e7970 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2016-01-24  Marcin Kościelnicki  <koriakin@0x04.net>
+
+	* gdb.trace/ftrace.exp: Select $r2 as test register for s390.
+	* gdb.trace/mi-trace-frame-collected.exp: Expect 2 registers on s390.
+	* gdb.trace/trace-common.h (x86_trace_dummy): Add s390 fast tracepoint
+	placeholder.
+	* lib/trace-support.exp: Add s390 registers.
+
 2016-01-23  Marcin Kościelnicki  <koriakin@0x04.net>
 
 	* gdb.trace/backtrace.exp: Bump stack collection fudge factor.
diff --git a/gdb/testsuite/gdb.trace/ftrace.exp b/gdb/testsuite/gdb.trace/ftrace.exp
index 15ad7e7..cca3a9c 100644
--- a/gdb/testsuite/gdb.trace/ftrace.exp
+++ b/gdb/testsuite/gdb.trace/ftrace.exp
@@ -246,6 +246,8 @@ if [is_amd64_regs_target] {
     set arg0exp "*(int *) (\$ebp + 8)"
 } elseif { [istarget "aarch64*-*-*"] } {
     set arg0exp "\$x0"
+} elseif { [istarget "s390*-*-*"] } {
+    set arg0exp "\$r2"
 } else {
     set arg0exp ""
 }
diff --git a/gdb/testsuite/gdb.trace/mi-trace-frame-collected.exp b/gdb/testsuite/gdb.trace/mi-trace-frame-collected.exp
index 0daaa25..499d3fb 100644
--- a/gdb/testsuite/gdb.trace/mi-trace-frame-collected.exp
+++ b/gdb/testsuite/gdb.trace/mi-trace-frame-collected.exp
@@ -93,9 +93,17 @@ proc test_trace_frame_collected { data_source } {
 
 	# Test MI command '-trace-frame-collected' dumps only
 	# collected registers.
-	mi_gdb_test "-trace-frame-collected" \
-	    "\\^done,explicit-variables=\\\[\{name=\"gdb_char_test\",value=\".*\"\}\\\],computed-expressions=\\\[\\\],registers=\\\[\{number=\"$decimal\",value=\"$hex\"\}\\\],tvars=\\\[\\\],memory=\\\[\{address=\"$hex\",length=\"1\"\}\\\]"\
-	    "-trace-frame-collected (register)"
+	if { [istarget "s390*-*-*"] } {
+	    # Only PC is collected, but on s390 PC is a pseudo-register -
+	    # collecting it also collects the underlying PSWA register.
+	    mi_gdb_test "-trace-frame-collected" \
+		"\\^done,explicit-variables=\\\[\{name=\"gdb_char_test\",value=\".*\"\}\\\],computed-expressions=\\\[\\\],registers=\\\[\{number=\"$decimal\",value=\"$hex\"\},\{number=\"$decimal\",value=\"$hex\"\}\\\],tvars=\\\[\\\],memory=\\\[\{address=\"$hex\",length=\"1\"\}\\\]"\
+		"-trace-frame-collected (register)"
+	} else {
+	    mi_gdb_test "-trace-frame-collected" \
+		"\\^done,explicit-variables=\\\[\{name=\"gdb_char_test\",value=\".*\"\}\\\],computed-expressions=\\\[\\\],registers=\\\[\{number=\"$decimal\",value=\"$hex\"\}\\\],tvars=\\\[\\\],memory=\\\[\{address=\"$hex\",length=\"1\"\}\\\]"\
+		"-trace-frame-collected (register)"
+	}
 
 	mi_gdb_test "-trace-find frame-number 1" \
 	    ".*\\^done,found=\"1\",tracepoint=\"${decimal}\",traceframe=\"1\",frame=\{.*" \
diff --git a/gdb/testsuite/gdb.trace/trace-common.h b/gdb/testsuite/gdb.trace/trace-common.h
index eceb182..a330024 100644
--- a/gdb/testsuite/gdb.trace/trace-common.h
+++ b/gdb/testsuite/gdb.trace/trace-common.h
@@ -48,6 +48,14 @@ x86_trace_dummy ()
        "    nop\n" \
        )
 
+#elif (defined __s390__)
+
+#define FAST_TRACEPOINT_LABEL(name) \
+  asm ("    .global " SYMBOL(name) "\n" \
+       SYMBOL(name) ":\n" \
+       "    mvc 0(8, %r15), 0(%r15)\n" \
+       )
+
 #else
 
 #error "unsupported architecture for trace tests"
diff --git a/gdb/testsuite/lib/trace-support.exp b/gdb/testsuite/lib/trace-support.exp
index f593c43..70f7b7f 100644
--- a/gdb/testsuite/lib/trace-support.exp
+++ b/gdb/testsuite/lib/trace-support.exp
@@ -36,6 +36,10 @@ if [is_amd64_regs_target] {
     set fpreg "x29"
     set spreg "sp"
     set pcreg "pc"
+} elseif [istarget "s390*-*-*"] {
+    set fpreg "r11"
+    set spreg "r15"
+    set pcreg "pc"
 } else {
     set fpreg "fp"
     set spreg "sp"
-- 
2.7.0