Variable size for regs mask in collection list

This patch changes collection_list to allow larger register masks.

The mask is changed from an array to a vector and is initialized to
hold the maximum possible remote register number.  The stringify
method is updated to resize temp_buf if needed.

gdb/ChangeLog:
2018-08-06  Pedro Franco de Carvalho  <pedromfc@linux.ibm.com>

	* tracepoint.h (collection_list) <m_regs_mask>: Change type to
	std::vector<unsigned char>.
	* tracepoint.c (collection_list::collection_list): Remove
	m_regs_mask initializer from initializer list.  Resize
	m_regs_mask using the largest remote register number.
	(collection_list::add_remote_register): Remove size check on
	m_regs_mask.  Use at to access element.
	(collection_list::stringify): Change type of temp_buf to
	gdb::char_vector.  Update uses of temp_buf.  Resize if needed to
	stringify the register mask.  Use pack_hex_byte for the register
	mask.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 57e6c4cb251a6afcbca881cf1f4c59a555ead651..d7bffb26123871be8d905f4997d1ad41e4b1d49d 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,17 @@
+2018-08-06  Pedro Franco de Carvalho  <pedromfc@linux.ibm.com>
+
+       * tracepoint.h (collection_list) <m_regs_mask>: Change type to
+       std::vector<unsigned char>.
+       * tracepoint.c (collection_list::collection_list): Remove
+       m_regs_mask initializer from initializer list.  Resize
+       m_regs_mask using the largest remote register number.
+       (collection_list::add_remote_register): Remove size check on
+       m_regs_mask.  Use at to access element.
+       (collection_list::stringify): Change type of temp_buf to
+       gdb::char_vector.  Update uses of temp_buf.  Resize if needed to
+       stringify the register mask.  Use pack_hex_byte for the register
+       mask.
+
 2018-08-06  Pedro Franco de Carvalho  <pedromfc@linux.ibm.com>
 
        * tracepoint.h (class collection_list) <add_register>: Remove.

diff --git a/gdb/tracepoint.c b/gdb/tracepoint.c
index 55ab13f9525c08bfaa6980117714c70458a4df9a..cd538f4498ff38db33282e28bf117758e7e7413c 100644 (file)
--- a/gdb/tracepoint.c
+++ b/gdb/tracepoint.c
@@ -822,10 +822,8 @@ collection_list::add_remote_register (unsigned int regno)
 {
   if (info_verbose)
     printf_filtered ("collect register %d\n", regno);
-  if (regno >= (8 * sizeof (m_regs_mask)))
-    error (_("Internal: register number %d too large for tracepoint"),
-          regno);
-  m_regs_mask[regno / 8] |= 1 << (regno % 8);
+
+  m_regs_mask.at (regno / 8) |= 1 << (regno % 8);
 }
 
 /* Add all the registers from the mask in AEXPR to the mask in the
@@ -1136,9 +1134,20 @@ collection_list::add_static_trace_data ()
 }
 
 collection_list::collection_list ()
-  : m_regs_mask (),
-    m_strace_data (false)
+  : m_strace_data (false)
 {
+  int max_remote_regno = 0;
+  for (int i = 0; i < gdbarch_num_regs (target_gdbarch ()); i++)
+    {
+      int remote_regno = (gdbarch_remote_register_number
+                         (target_gdbarch (), i));
+
+      if (remote_regno >= 0 && remote_regno > max_remote_regno)
+       max_remote_regno = remote_regno;
+    }
+
+  m_regs_mask.resize ((max_remote_regno / 8) + 1);
+
   m_memranges.reserve (128);
   m_aexprs.reserve (128);
 }
@@ -1148,7 +1157,8 @@ collection_list::collection_list ()
 std::vector<std::string>
 collection_list::stringify ()
 {
-  char temp_buf[2048];
+  gdb::char_vector temp_buf (2048);
+
   int count;
   char *end;
   long i;
@@ -1158,35 +1168,45 @@ collection_list::stringify ()
     {
       if (info_verbose)
        printf_filtered ("\nCollecting static trace data\n");
-      end = temp_buf;
+      end = temp_buf.data ();
       *end++ = 'L';
-      str_list.emplace_back (temp_buf, end - temp_buf);
+      str_list.emplace_back (temp_buf.data (), end - temp_buf.data ());
     }
 
-  for (i = sizeof (m_regs_mask) - 1; i > 0; i--)
+  for (i = m_regs_mask.size () - 1; i > 0; i--)
     if (m_regs_mask[i] != 0)    /* Skip leading zeroes in regs_mask.  */
       break;
   if (m_regs_mask[i] != 0)     /* Prepare to send regs_mask to the stub.  */
     {
       if (info_verbose)
        printf_filtered ("\nCollecting registers (mask): 0x");
-      end = temp_buf;
+
+      /* One char for 'R', one for the null terminator and two per
+        mask byte.  */
+      std::size_t new_size = (i + 1) * 2 + 2;
+      if (new_size > temp_buf.size ())
+       temp_buf.resize (new_size);
+
+      end = temp_buf.data ();
       *end++ = 'R';
       for (; i >= 0; i--)
        {
          QUIT;                 /* Allow user to bail out with ^C.  */
          if (info_verbose)
            printf_filtered ("%02X", m_regs_mask[i]);
-         sprintf (end, "%02X", m_regs_mask[i]);
-         end += 2;
+
+         end = pack_hex_byte (end, m_regs_mask[i]);
        }
-      str_list.emplace_back (temp_buf);
+      *end = '\0';
+
+      str_list.emplace_back (temp_buf.data ());
     }
   if (info_verbose)
     printf_filtered ("\n");
   if (!m_memranges.empty () && info_verbose)
     printf_filtered ("Collecting memranges: \n");
-  for (i = 0, count = 0, end = temp_buf; i < m_memranges.size (); i++)
+  for (i = 0, count = 0, end = temp_buf.data ();
+       i < m_memranges.size (); i++)
     {
       QUIT;                    /* Allow user to bail out with ^C.  */
       if (info_verbose)
@@ -1200,9 +1220,9 @@ collection_list::stringify ()
        }
       if (count + 27 > MAX_AGENT_EXPR_LEN)
        {
-         str_list.emplace_back (temp_buf, count);
+         str_list.emplace_back (temp_buf.data (), count);
          count = 0;
-         end = temp_buf;
+         end = temp_buf.data ();
        }
 
       {
@@ -1222,7 +1242,7 @@ collection_list::stringify ()
       }
 
       count += strlen (end);
-      end = temp_buf + count;
+      end = temp_buf.data () + count;
     }
 
   for (i = 0; i < m_aexprs.size (); i++)
@@ -1230,9 +1250,9 @@ collection_list::stringify ()
       QUIT;                    /* Allow user to bail out with ^C.  */
       if ((count + 10 + 2 * m_aexprs[i]->len) > MAX_AGENT_EXPR_LEN)
        {
-         str_list.emplace_back (temp_buf, count);
+         str_list.emplace_back (temp_buf.data (), count);
          count = 0;
-         end = temp_buf;
+         end = temp_buf.data ();
        }
       sprintf (end, "X%08X,", m_aexprs[i]->len);
       end += 10;               /* 'X' + 8 hex digits + ',' */
@@ -1244,9 +1264,9 @@ collection_list::stringify ()
 
   if (count != 0)
     {
-      str_list.emplace_back (temp_buf, count);
+      str_list.emplace_back (temp_buf.data (), count);
       count = 0;
-      end = temp_buf;
+      end = temp_buf.data ();
     }
 
   return str_list;

diff --git a/gdb/tracepoint.h b/gdb/tracepoint.h
index 8bdad3567e91ae5b932a4ac52e2f6e24d5885915..c185672cc1b8d0f61e40a9fbe114c854218029d2 100644 (file)
--- a/gdb/tracepoint.h
+++ b/gdb/tracepoint.h
@@ -292,8 +292,9 @@ public:
   { return m_computed; }
 
 private:
-  /* room for up to 256 regs */
-  unsigned char m_regs_mask[32];
+  /* We need the allocator zero-initialize the mask, so we don't use
+     gdb::byte_vector.  */
+  std::vector<unsigned char> m_regs_mask;
 
   std::vector<memrange> m_memranges;