Rename common to gdbsupport

[deliverable/binutils-gdb.git] / gdb / gdbserver / linux-i386-ipa.c

diff --git a/gdb/gdbserver/linux-i386-ipa.c b/gdb/gdbserver/linux-i386-ipa.c
index ea6802f432f6f52953a1251c88f60295b2f326fc..2e3d1ac7feed95eaace72454ca83423a534ff485 100644 (file)
--- a/gdb/gdbserver/linux-i386-ipa.c
+++ b/gdb/gdbserver/linux-i386-ipa.c
@@ -1,7 +1,7 @@
 /* GNU/Linux/x86 specific low level interface, for the in-process
    agent library for GDB.
 
-   Copyright (C) 2010 Free Software Foundation, Inc.
+   Copyright (C) 2010-2019 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
@@ -19,6 +19,10 @@
    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"
+#include "gdbsupport/x86-xstate.h"
 
 /* GDB register numbers.  */
 
@@ -45,9 +49,6 @@ enum i386_gdb_regnum
 
 #define i386_num_regs 16
 
-/* Defined in auto-generated file i386-linux.c.  */
-void init_registers_i386_linux (void);
-
 #define FT_CR_EAX 15
 #define FT_CR_ECX 14
 #define FT_CR_EDX 13
@@ -95,8 +96,8 @@ supply_fast_tracepoint_registers (struct regcache *regcache,
     }
 }
 
-ULONGEST __attribute__ ((visibility("default"), used))
-gdb_agent_get_raw_reg (unsigned char *raw_regs, int regnum)
+ULONGEST
+get_raw_reg (const unsigned char *raw_regs, int regnum)
 {
   /* This should maybe be allowed to return an error code, or perhaps
      better, have the emit_reg detect this, and emit a constant zero,
@@ -178,7 +179,7 @@ supply_static_tracepoint_registers (struct regcache *regcache,
            }
            break;
          default:
-           internal_error ("unhandled register size: %d",
+           internal_error (__FILE__, __LINE__, "unhandled register size: %d",
                            i386_st_collect_regmap[i].size);
          }
       }
@@ -191,8 +192,103 @@ supply_static_tracepoint_registers (struct regcache *regcache,
    may use it proper at some point.  */
 const char *gdbserver_xmltarget;
 
+/* Attempt to allocate memory for trampolines in the first 64 KiB of
+   memory to enable smaller jump patches.  */
+
+static void
+initialize_fast_tracepoint_trampoline_buffer (void)
+{
+  const CORE_ADDR buffer_end = 64 * 1024;
+  /* Ensure that the buffer will be at least 1 KiB in size, which is
+     enough space for over 200 fast tracepoints.  */
+  const int min_buffer_size = 1024;
+  char buf[IPA_BUFSIZ];
+  CORE_ADDR mmap_min_addr = buffer_end + 1;
+  ULONGEST buffer_size;
+  FILE *f = fopen ("/proc/sys/vm/mmap_min_addr", "r");
+
+  if (!f)
+    {    
+      snprintf (buf, sizeof (buf), "mmap_min_addr open failed: %s",
+               strerror (errno));
+      set_trampoline_buffer_space (0, 0, buf);
+      return;
+    }
+
+  if (fgets (buf, IPA_BUFSIZ, f))
+    sscanf (buf, "%llu", &mmap_min_addr);
+      
+  fclose (f);
+      
+  buffer_size = buffer_end - mmap_min_addr;
+
+  if (buffer_size >= min_buffer_size)
+    {
+      if (mmap ((void *) (uintptr_t) mmap_min_addr, buffer_size,
+               PROT_READ | PROT_EXEC | PROT_WRITE,
+               MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS,
+               -1, 0)
+         != MAP_FAILED)
+       set_trampoline_buffer_space (mmap_min_addr, buffer_end, NULL);
+      else
+       {
+         snprintf (buf, IPA_BUFSIZ, "low-64K-buffer mmap() failed: %s",
+                   strerror (errno));
+         set_trampoline_buffer_space (0, 0, buf);
+       }
+    }
+  else
+    {
+      snprintf (buf, IPA_BUFSIZ, "mmap_min_addr is %d, must be %d or less",
+               (int) mmap_min_addr, (int) buffer_end - min_buffer_size);
+      set_trampoline_buffer_space (0, 0, buf);
+    }
+}
+
+/* Map the tdesc index to xcr0 mask.  */
+static uint64_t idx2mask[X86_TDESC_LAST] = {
+  X86_XSTATE_X87_MASK,
+  X86_XSTATE_SSE_MASK,
+  X86_XSTATE_AVX_MASK,
+  X86_XSTATE_MPX_MASK,
+  X86_XSTATE_AVX_MPX_MASK,
+  X86_XSTATE_AVX_AVX512_MASK,
+  X86_XSTATE_AVX_MPX_AVX512_PKU_MASK,
+};
+
+/* Return target_desc to use for IPA, given the tdesc index passed by
+   gdbserver.  */
+
+const struct target_desc *
+get_ipa_tdesc (int idx)
+{
+  if (idx >= X86_TDESC_LAST)
+    {
+      internal_error (__FILE__, __LINE__,
+                     "unknown ipa tdesc index: %d", idx);
+    }
+  return i386_linux_read_description (idx2mask[idx]);
+}
+
+/* Allocate buffer for the jump pads.  On i386, we can reach an arbitrary
+   address with a jump instruction, so just allocate normally.  */
+
+void *
+alloc_jump_pad_buffer (size_t size)
+{
+  void *res = mmap (NULL, size, PROT_READ | PROT_WRITE | PROT_EXEC,
+                   MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+
+  if (res == MAP_FAILED)
+    return NULL;
+
+  return res;
+}
+
 void
 initialize_low_tracepoint (void)
 {
-  init_registers_i386_linux ();
+  initialize_fast_tracepoint_trampoline_buffer ();
+  for (auto i = 0; i < X86_TDESC_LAST; i++)
+    i386_linux_read_description (idx2mask[i]);
 }