gdb/csky support .reg2 for kernel 4.x and later

When kernel's version >= 4.x, the size of .reg2 section will be 400.
Contents of .reg2 are {
    unsigned long vr[96];
    unsigned long fcr;
    unsigned long fesr;
    unsigned long fid;
    unsigned long reserved;
};

VR[96] means: (vr0~vr15) + (fr16~fr31), each Vector register is
128-bits, each Float register is 64 bits, the total size is
(4*96).

In addition, for fr0~fr15, each FRx is the lower 64 bits of the
corresponding VRx. So fr0~fr15 and vr0~vr15 regisetrs use the same
offset.

diff --git a/gdb/csky-linux-tdep.c b/gdb/csky-linux-tdep.c
index 440045e771312cb91a1bfc1d87b93916dbf112d4..106f629b8b0868168a944140be84f5d8f8347403 100644 (file)
--- a/gdb/csky-linux-tdep.c
+++ b/gdb/csky-linux-tdep.c
@@ -36,6 +36,8 @@
 #define SIZEOF_CSKY_GREGSET 34*4
 /* Float regset fesr fsr fr0-fr31 for CK810.  */
 #define SIZEOF_CSKY_FREGSET 34*4
+/* Float regset vr0~vr15 fr15~fr31, reserved for CK810 when kernel 4.x.  */
+#define SIZEOF_CSKY_FREGSET_K4X  400
 
 /* Offset mapping table from core_section to regcache of general
    registers for ck810.  */
@@ -118,16 +120,80 @@ csky_supply_fregset (const struct regset *regset,
   int fregset_num = ARRAY_SIZE (csky_fregset_offset);
 
   gdb_assert (len >= SIZEOF_CSKY_FREGSET);
-  for (i = 0; i < fregset_num; i++)
+  if (len == SIZEOF_CSKY_FREGSET)
     {
-      if ((regnum == csky_fregset_offset[i] || regnum == -1)
-         && csky_fregset_offset[i] != -1)
+      for (i = 0; i < fregset_num; i++)
        {
-         int num = csky_fregset_offset[i];
-         offset += register_size (gdbarch, num);
-         regcache->raw_supply (csky_fregset_offset[i], fregs + offset);
+         if ((regnum == csky_fregset_offset[i] || regnum == -1)
+             && csky_fregset_offset[i] != -1)
+           {
+             int num = csky_fregset_offset[i];
+             offset += register_size (gdbarch, num);
+             regcache->raw_supply (csky_fregset_offset[i], fregs + offset);
+           }
        }
     }
+  else if (len == SIZEOF_CSKY_FREGSET_K4X)
+    {
+      /* When kernel version >= 4.x, .reg2 size will be 400.
+        Contents is {
+         unsigned long vr[96];
+         unsigned long fcr;
+         unsigned long fesr;
+         unsigned long fid;
+         unsigned long reserved;
+        }
+        VR[96] means: (vr0~vr15) + (fr16~fr31), each Vector register is
+        128-bits, each Float register is 64 bits, the total size is
+        (4*96).
+
+        In addition, for fr0~fr15, each FRx is the lower 64 bits of the
+        corresponding VRx. So fr0~fr15 and vr0~vr15 regisetrs use the same
+        offset.  */
+      int fcr_regno[] = {122, 123, 121}; /* fcr, fesr, fid.  */
+
+      /* Supply vr0~vr15.  */
+      for (i = 0; i < 16; i ++)
+       {
+         if (gdbarch_register_name (gdbarch, (CSKY_VR0_REGNUM + i)))
+           {
+             offset = 16 * i;
+             regcache->raw_supply (CSKY_VR0_REGNUM + i, fregs + offset);
+           }
+       }
+      /* Supply fr0~fr15.  */
+      for (i = 0; i < 16; i ++)
+       {
+         if (gdbarch_register_name (gdbarch, (CSKY_FR0_REGNUM + i)))
+           {
+             offset = 16 * i;
+             regcache->raw_supply (CSKY_FR0_REGNUM + i, fregs + offset);
+           }
+       }
+      /* Supply fr16~fr31.  */
+      for (i = 0; i < 16; i ++)
+       {
+         if (gdbarch_register_name (gdbarch, (CSKY_FR16_REGNUM + i)))
+           {
+             offset = (16 * 16) + (8 * i);
+             regcache->raw_supply (CSKY_FR16_REGNUM + i, fregs + offset);
+           }
+       }
+     /* Supply fcr, fesr, fid.  */
+      for (i = 0; i < 3; i ++)
+       {
+         if (gdbarch_register_name (gdbarch, fcr_regno[i]))
+           {
+             offset = (16 * 16) + (16 * 8) + (4 * i);
+             regcache->raw_supply (fcr_regno[i], fregs + offset);
+           }
+       }
+    }
+  else
+    {
+      warning (_("Unknow size %ld of section .reg2, can not get value"
+                " of float registers."), len);
+    }
 }
 
 /* Implement the collect_regset hook for FP registers in core files.  */
@@ -144,14 +210,70 @@ csky_collect_fregset (const struct regset *regset,
   int offset = 0;
 
   gdb_assert (len >= SIZEOF_CSKY_FREGSET);
-  for (regno = 0; regno < fregset_num; regno++)
+  if (len == SIZEOF_CSKY_FREGSET)
+    {
+      for (regno = 0; regno < fregset_num; regno++)
+       {
+         if ((regnum == csky_fregset_offset[regno] || regnum == -1)
+              && csky_fregset_offset[regno] != -1)
+           {
+             offset += register_size (gdbarch, csky_fregset_offset[regno]);
+             regcache->raw_collect (regno, fregs + offset);
+           }
+       }
+    }
+  else if (len == SIZEOF_CSKY_FREGSET_K4X)
     {
-      if ((regnum == csky_fregset_offset[regno] || regnum == -1)
-         && csky_fregset_offset[regno] != -1)
+      /* When kernel version >= 4.x, .reg2 size will be 400.
+        Contents is {
+          unsigned long vr[96];
+          unsigned long fcr;
+          unsigned long fesr;
+          unsigned long fid;
+          unsigned long reserved;
+        }
+        VR[96] means: (vr0~vr15) + (fr16~fr31), each Vector register is$
+        128-bits, each Float register is 64 bits, the total size is$
+        (4*96).$
+
+        In addition, for fr0~fr15, each FRx is the lower 64 bits of the$
+        corresponding VRx. So fr0~fr15 and vr0~vr15 regisetrs use the same$
+        offset.  */
+      int i = 0;
+      int fcr_regno[] = {122, 123, 121}; /* fcr, fesr, fid.  */
+
+      /* Supply vr0~vr15.  */
+      for (i = 0; i < 16; i ++)
        {
-         offset += register_size (gdbarch, csky_fregset_offset[regno]);
-         regcache->raw_collect (regno, fregs + offset);
+         if (gdbarch_register_name (gdbarch, (CSKY_VR0_REGNUM + i)))
+           {
+             offset = 16 * i;
+             regcache ->raw_collect (CSKY_VR0_REGNUM + i, fregs + offset);
+           }
        }
+      /* Supply fr16~fr31.  */
+      for (i = 0; i < 16; i ++)
+       {
+         if (gdbarch_register_name (gdbarch, (CSKY_FR16_REGNUM + i)))
+           {
+             offset = (16 * 16) + (8 * i);
+             regcache ->raw_collect (CSKY_FR16_REGNUM + i, fregs + offset);
+           }
+       }
+      /* Supply fcr, fesr, fid.  */
+      for (i = 0; i < 3; i ++)
+       {
+         if (gdbarch_register_name (gdbarch, fcr_regno[i]))
+           {
+             offset = (16 * 16) + (16 * 8) + (4 * i);
+             regcache ->raw_collect (fcr_regno[i], fregs + offset);
+           }
+       }
+    }
+  else
+    {
+      warning (_("Unknow size %ld of section .reg2, will not set value"
+                " of float registers."), len);
     }
 }
 
@@ -166,7 +288,10 @@ static const struct regset csky_regset_float =
 {
   NULL,
   csky_supply_fregset,
-  csky_collect_fregset
+  csky_collect_fregset,
+  /* Allow .reg2 to have a different size, and the size of .reg2 should
+     always be bigger than SIZEOF_CSKY_FREGSET.  */
+  1
 };
 
 /* Iterate over core file register note sections.  */

diff --git a/gdb/csky-tdep.h b/gdb/csky-tdep.h
index 54000ab8287ed648b5298350c1280bef65514eda..3ee50fc593103adf2f7e074a6360afcbd3816767 100644 (file)
--- a/gdb/csky-tdep.h
+++ b/gdb/csky-tdep.h
@@ -93,6 +93,9 @@ enum csky_regnum
   CSKY_PSR_REGNUM = CSKY_CR0_REGNUM,
 
   CSKY_MAX_REGISTER_SIZE = 16,
+
+  /* Actually, the max regs number should be 1187. But if the
+     gdb stub does not send a tdesc-xml file to gdb, 253 works. */
   CSKY_MAX_REGS = 253
 };