IPA: Add alloc_jump_pad_buffer target hook.

[deliverable/binutils-gdb.git] / gdb / gdbserver / linux-amd64-ipa.c

diff --git a/gdb/gdbserver/linux-amd64-ipa.c b/gdb/gdbserver/linux-amd64-ipa.c
index 70889d293a72ccc4f7e903f57cd25c57a1b09fd8..c623dc204bed7b34694494cdb4e849ed1efe67ee 100644 (file)
--- a/gdb/gdbserver/linux-amd64-ipa.c
+++ b/gdb/gdbserver/linux-amd64-ipa.c
@@ -19,6 +19,7 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include "server.h"
+#include <sys/mman.h>
 #include "tracepoint.h"
 #include "linux-x86-tdesc.h"
 
@@ -190,6 +191,23 @@ get_ipa_tdesc (int idx)
     }
 }
 
+/* Allocate buffer for the jump pads.  Since we're using 32-bit jumps
+   to reach them, and the executable is at low addresses, MAP_32BIT
+   works just fine.  Shared libraries, being allocated at the top,
+   are unfortunately out of luck.  */
+
+void *
+alloc_jump_pad_buffer (size_t size)
+{
+  void *res = mmap (NULL, size, PROT_READ | PROT_WRITE | PROT_EXEC,
+                   MAP_PRIVATE | MAP_ANONYMOUS | MAP_32BIT, -1, 0);
+
+  if (res == MAP_FAILED)
+    return NULL;
+
+  return res;
+}
+
 void
 initialize_low_tracepoint (void)
 {