[PATCH] pickles: add pickles for CTF Frame section

[Indu Bhagat]

This patch adds new pickles to read and manipulate the CTF Frame
section.  CTF Frame format is a lightweight and compact unwind format
designed to serve the usecases of fast, online stack unwinding. CTF Frame
format is currently being designed and discussed in the open source
GNU/Linux community.

https://sourceware.org/pipermail/binutils/2022-June/121478.html

This pickle will be adapted in the future as the format evolves.

2022-06-29  Indu Bhagat  <indu.bhagat@oracle.com>

ChangeLog:

        * pickles/Makefile.am: Include CTF Frame pickles.
        * pickles/ctf-frame-dump.pk: New file.
        * pickles/ctf-frame.pk: Likewise.
---
 pickles/Makefile.am       |   1 +
 pickles/ctf-frame-dump.pk |  68 +++++++++++++
 pickles/ctf-frame.pk      | 200 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 269 insertions(+)
 create mode 100644 pickles/ctf-frame-dump.pk
 create mode 100644 pickles/ctf-frame.pk

diff --git a/pickles/Makefile.am b/pickles/Makefile.am
index ab2970ab..8d786e82 100644
--- a/pickles/Makefile.am
+++ b/pickles/Makefile.am
@@ -2,6 +2,7 @@ picklesdir = $(pkgdatadir)/pickles
 dist_pickles_DATA = elf-common.pk elf-64.pk elf-32.pk elf.pk ctf.pk 
ctf-dump.pk leb128.pk \
                     bpf.pk btf.pk btf-ext.pk btf-dump.pk bmp.pk \
                     color.pk rgb24.pk id3v1.pk ios.pk diff.pk pk-table.pk \
+                   ctf-frame.pk ctf-frame-dump.pk \
                    eh-frame.pk dwarf-eh-frame-hdr.pk \
                     dwarf.pk dwarf-common.pk dwarf-frame.pk dwarf-pubnames.pk \
                     dwarf-types.pk time.pk argp.pk pktest.pk mbr.pk ustar.pk \
diff --git a/pickles/ctf-frame-dump.pk b/pickles/ctf-frame-dump.pk
new file mode 100644
index 00000000..ad90d423
--- /dev/null
+++ b/pickles/ctf-frame-dump.pk
@@ -0,0 +1,68 @@
+/* ctf-frame-dump.pk - Utilities for dumping CTF Frame information.  */
+
+/* Copyright (C) 2022 Free Software Foundation.  */
+
+/* This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/* This file contains routines for dumping out CTF Frame information.  */
+
+load "ctf-frame.pk";
+
+/* Dump each FDE in the CTF Frame section.  */
+
+fun ctf_frame_dump_fdes = (CTF_Frame_section ctf_frame_arg) void:
+{
+  var i = 0;
+  for (index in ctf_frame_arg.funcidx)
+    printf ("%u32d:   %v \n", i++, index);
+}
+
+/* Dump CTF Frame FREs.  */
+
+fun ctf_frame_dump_fres = (CTF_Frame_section ctf_frame_arg) void:
+{
+  var i = 0;
+
+  for (func in ctf_frame_arg.funcidx)
+    {
+      /* Get the FRE type.  */
+      var fre_type = func.func_info.fre_type;
+      var num_fres = func.func_num_fres;
+      var fre_off = ctf_frame_arg.header'size + 
ctf_frame_arg.header.cth_freoff;
+
+      if (fre_type == CTF_FRAME_ROW_ENTRY_TYPE_ADDR1)
+       {
+         var fres = func.get_fres_addr1s (fre_off);
+         /* print fres.  */
+         for (fre in fres)
+           printf ("%u32d:   %v \n", i++, fre);
+       }
+      else if (fre_type == CTF_FRAME_ROW_ENTRY_TYPE_ADDR2)
+       {
+         var fres = func.get_fres_addr2s (fre_off);
+         /* print fres.  */
+         for (fre in fres)
+           printf ("%u32d:   %v \n", i++, fre);
+       }
+      else if (fre_type == CTF_FRAME_ROW_ENTRY_TYPE_ADDR4)
+       {
+         var fres = func.get_fres_addr4s (fre_off);
+         /* print fres.  */
+         for (fre in fres)
+           printf ("%u32d:   %v \n", i++, fre);
+       }
+
+    }
+}
diff --git a/pickles/ctf-frame.pk b/pickles/ctf-frame.pk
new file mode 100644
index 00000000..059c20c7
--- /dev/null
+++ b/pickles/ctf-frame.pk
@@ -0,0 +1,200 @@
+/* ctf-frame.pk - CTF Frame implementation for GNU poke.  */
+
+/* Copyright (C) 2022 Free Software Foundation.  */
+
+/* This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+load elf;
+
+/* Constants for CTF Preamble.  */
+var CTF_FRAME_VERSION_1 = 1;
+var CTF_FRAME_MAGIC = 0xdee2;
+/* Various flags for CTF Frame section.  */
+var CTF_FRAME_F_FDE_SORTED = 0x1;
+var CTF_FRAME_F_FRAME_POINTER = 0x2;
+
+type CTF_Frame_Preamble =
+  struct
+  {
+    uint<16> ctfp_magic : ((ctfp_magic == CTF_FRAME_MAGIC)
+                          || (ctfp_magic == 0xe2de && set_endian 
(!get_endian)))
+                         = CTF_FRAME_MAGIC;
+
+    byte ctfp_version = CTF_FRAME_VERSION_1;
+    byte ctfp_flags;
+  };
+
+var CTF_FRAME_ROW_ENTRY_TYPE_ADDR1 = 1;
+var CTF_FRAME_ROW_ENTRY_TYPE_ADDR2 = 2;
+var CTF_FRAME_ROW_ENTRY_TYPE_ADDR4 = 3;
+
+/* CTF Frame FDE types.
+   The CTF Frame format has two possible representations for functions.  The
+   choice of which type to use is made according to the instruction patterns
+   in the relevant program stub.  */
+
+/* Unwinders perform a (PC >= FRE_START_ADDR) to look up a matching FRE.  */
+var CTF_FRAME_FUNC_DESC_ENTRY_TYPE_PCINC = 0;
+/* Unwinders perform a (PC & FRE_START_ADDR_AS_MASK >= FRE_START_ADDR_AS_MASK)
+   to look up a matching FRE.  */
+var CTF_FRAME_FUNC_DESC_ENTRY_TYPE_PCMASK = 1;
+
+/* CTF Frame FDE Function Info.  */
+type CTF_Frame_Func_Info =
+  struct
+{
+  uint<3> unused;
+  uint<1> fde_type : fde_type in [CTF_FRAME_FUNC_DESC_ENTRY_TYPE_PCINC,
+                                 CTF_FRAME_FUNC_DESC_ENTRY_TYPE_PCMASK];
+  uint<4> fre_type : fre_type in [CTF_FRAME_ROW_ENTRY_TYPE_ADDR1,
+                                 CTF_FRAME_ROW_ENTRY_TYPE_ADDR2,
+                                 CTF_FRAME_ROW_ENTRY_TYPE_ADDR4];
+};
+
+/* Supported ABIs/Arch.  */
+var CTF_FRAME_ABI_AARCH64_ENDIAN_BIG = 1; /* AARCH64 little endian.  */
+var CTF_FRAME_ABI_AARCH64_ENDIAN_LITTLE = 2; /* AARCH64 big endian.  */
+var CTF_FRAME_ABI_AMD64_ENDIAN_LITTLE = 3; /* AMD64 little endian.  */
+
+var CTF_FRAME_FRE_TYPE_BASIC = 0x0;
+
+type CTF_Frame_Header =
+  struct
+  {
+    CTF_Frame_Preamble cth_frame_preamble;
+    byte cth_frame_abi_arch : cth_frame_abi_arch in 
[CTF_FRAME_ABI_AARCH64_ENDIAN_BIG,
+                                                   
CTF_FRAME_ABI_AARCH64_ENDIAN_LITTLE,
+                                                   
CTF_FRAME_ABI_AMD64_ENDIAN_LITTLE];
+    int<8> cth_cfa_fixed_bp_offset;
+    int<8> cth_cfa_fixed_ra_offset;
+    uint<32> cth_num_fdes;
+    uint<32> cth_num_fres;
+    offset<uint32,B> cth_frelen;
+
+    offset<uint32,B> cth_fdeoff;
+    offset<uint32,B> cth_freoff;
+  };
+
+var CTF_FRAME_FRE_OFFSET_1B = 0;
+var CTF_FRAME_FRE_OFFSET_2B = 1;
+var CTF_FRAME_FRE_OFFSET_4B = 2;
+/* At this time, a max of 3 distinct offsets are supported.  */
+var CTF_FRAME_FRE_OFFSET_NUM = 3;
+
+/* A CTF FRE can be SP or BP based.  */
+var CTF_FRAME_BASE_REG_BP = 0;
+var CTF_FRAME_BASE_REG_SP = 1;
+
+type CTF_Frame_FRE_Info =
+  struct byte
+  {
+    uint<1> unused;
+    uint<2> offset_size : offset_size in [CTF_FRAME_FRE_OFFSET_1B,
+                                         CTF_FRAME_FRE_OFFSET_2B,
+                                         CTF_FRAME_FRE_OFFSET_4B];
+    uint<4> offset_num : offset_num <= CTF_FRAME_FRE_OFFSET_NUM;
+    uint<1> base_reg_id : base_reg_id in [CTF_FRAME_BASE_REG_BP,
+                                         CTF_FRAME_BASE_REG_SP];
+  };
+
+/* CTF FRE.  */
+type CTF_FRE_addr1 =
+  struct
+  {
+    uint<8> fre_start_address;
+    CTF_Frame_FRE_Info fre_info;
+    union
+    {
+      int<8>[fre_info.offset_num] offsets_1B
+         : fre_info.offset_size == CTF_FRAME_FRE_OFFSET_1B;
+      int<16>[fre_info.offset_num] offsets_2B
+         : fre_info.offset_size == CTF_FRAME_FRE_OFFSET_2B;
+      int<32>[fre_info.offset_num] offsets_4B
+         : fre_info.offset_size == CTF_FRAME_FRE_OFFSET_4B;
+    } offsets;
+  };
+
+type CTF_FRE_addr2 =
+  struct
+  {
+    uint<16> fre_start_address;
+    CTF_Frame_FRE_Info fre_info;
+    union
+    {
+      int<8>[fre_info.offset_num] offsets_1B
+         : fre_info.offset_size == CTF_FRAME_FRE_OFFSET_1B;
+      int<16>[fre_info.offset_num] offsets_2B
+         : fre_info.offset_size == CTF_FRAME_FRE_OFFSET_2B;
+      int<32>[fre_info.offset_num] offsets_4B
+         : fre_info.offset_size == CTF_FRAME_FRE_OFFSET_4B;
+    } offsets;
+  };
+
+type CTF_FRE_addr4=
+  struct
+  {
+    uint<32> fre_start_address;
+    CTF_Frame_FRE_Info fre_info;
+    union
+    {
+      int<8>[fre_info.offset_num] offsets_1B
+         : fre_info.offset_size == CTF_FRAME_FRE_OFFSET_1B;
+      int<16>[fre_info.offset_num] offsets_2B
+         : fre_info.offset_size == CTF_FRAME_FRE_OFFSET_2B;
+      int<32>[fre_info.offset_num] offsets_4B
+         : fre_info.offset_size == CTF_FRAME_FRE_OFFSET_4B;
+    } offsets;
+  };
+
+
+type CTF_Frame_Func_Desc_Entry =
+  struct
+  {
+    uint<32> func_start_address;
+    uint<32> func_size;
+    offset<uint32,B> func_freoff;
+    uint<32> func_num_fres;
+    CTF_Frame_Func_Info func_info;
+
+    method get_fres_addr1s = (offset<uint32,B> hdr_freoff) CTF_FRE_addr1[]:
+      {
+       var off = hdr_freoff + func_freoff;
+       return CTF_FRE_addr1[func_num_fres] @ off;
+      }
+    method get_fres_addr2s = (offset<uint32,B> hdr_freoff) CTF_FRE_addr2[]:
+      {
+       var off = hdr_freoff + func_freoff;
+       return CTF_FRE_addr2[func_num_fres] @ off;
+      }
+    method get_fres_addr4s = (offset<uint32,B> hdr_freoff) CTF_FRE_addr4[]:
+      {
+       var off = hdr_freoff + func_freoff;
+       return CTF_FRE_addr4[func_num_fres] @ off;
+      }
+  };
+
+type CTF_Frame_section =
+  struct
+  {
+    CTF_Frame_Header header;
+
+    var func_index_off = OFFSET + header.cth_fdeoff;
+    var func_index_size = header.cth_freoff - header.cth_fdeoff;
+    var fre_off = OFFSET + header.cth_freoff;
+    var fre_size = header.cth_frelen;
+
+    CTF_Frame_Func_Desc_Entry[func_index_size] funcidx @ func_index_off;
+    byte[fre_size] fres_data_bytes @ fre_off;
+  };
-- 
2.31.1