binutils/readelf: build against msgpack, dump NT_AMDGPU_METADATA note contents

The AMDGPU HSA OS ABI (code object v3 and above) defines the
NT_AMDGPU_METADATA ELF note [1].  The content is a msgpack object
describing, among other things, the kernels present in the code object
and how to call them.

I think it would be useful for readelf to be able to display the content
of those notes.  msgpack is a structured format, a bit like JSON, except
not text-based.  It is therefore possible to dump the contents in
human-readable form without knowledge of the specific layout of the
note.

Add configury to binutils to optionally check for the msgpack C library
[2].  Add There is a new --with{,out}-msgpack configure flag, and the actual
library lookup is done using pkg-config.

If msgpack support is enabled, dumping a NT_AMDGPU_METADATA note looks
like:

    $ readelf --notes amdgpu-code-object
    Displaying notes found in: .note
      Owner                Data size        Description
      AMDGPU               0x0000040d       NT_AMDGPU_METADATA (code object metadata)
        {
          "amdhsa.kernels": [
            {
              ".args": [
                {
                  ".address_space": "global",
                  ".name": "out.coerce",
                  ".offset": 0,
                  ".size": 8,
                  ".value_kind": "global_buffer",
                },
      <snip>

If msgpack support is disabled, dump the contents as hex, as is done
with notes that are not handled in a special way.  This allows one to
decode the contents manually (maybe using a command-line msgpack
decoder) if really needed.

[1] https://llvm.org/docs/AMDGPUUsage.html#code-object-metadata
[2] https://github.com/msgpack/msgpack-c/tree/c_master

binutils/ChangeLog:

	* Makefile.am (readelf_CFLAGS): New.
	(readelf_LDADD): Add MSGPACK_LIBS.
	* Makefile.in: Re-generate.
	* config.in: Re-generate.
	* configure: Re-generate.
	* configure.ac: Add --with-msgpack flag and check for msgpack
	using pkg-config.
	* readelf.c: Include msgpack.h if HAVE_MSGPACK.
	(print_note_contents_hex): New.
	(print_indents): New.
	(dump_msgpack_obj): New.
	(dump_msgpack): New.
	(print_amdgpu_note): New.
	(process_note): Handle NT_AMDGPU_METADATA note contents.
	Use print_note_contents_hex.

Change-Id: Ia60a654e620bc32dfdb1bccd845594e2af328b84

1 files changed, 134 insertions, 3 deletions

diff --git a/binutils/configure b/binutils/configure
index 19d82ba..f3ad831 100755
--- a/binutils/configure
+++ b/binutils/configure
@@ -648,6 +648,8 @@ BUILD_DLLTOOL
 BUILD_SRCONV
 LTLIBICONV
 LIBICONV
+MSGPACK_LIBS
+MSGPACK_CFLAGS
 zlibinc
 zlibdir
 DEMANGLER_NAME
@@ -830,6 +832,7 @@ enable_build_warnings
 enable_nls
 enable_maintainer_mode
 with_system_zlib
+with_msgpack
 enable_rpath
 with_libiconv_prefix
 with_libiconv_type
@@ -849,7 +852,9 @@ PKG_CONFIG_LIBDIR
 DEBUGINFOD_CFLAGS
 DEBUGINFOD_LIBS
 YACC
-YFLAGS'
+YFLAGS
+MSGPACK_CFLAGS
+MSGPACK_LIBS'
 
 
 # Initialize some variables set by options.
@@ -1512,6 +1517,7 @@ Optional Packages:
   --with-debuginfod       Enable debuginfo lookups with debuginfod
                           (auto/yes/no)
   --with-system-zlib      use installed libz
+  --with-msgpack          Enable msgpack support (auto/yes/no)
   --with-gnu-ld           assume the C compiler uses GNU ld default=no
   --with-libiconv-prefix[=DIR]  search for libiconv in DIR/include and DIR/lib
   --without-libiconv-prefix     don't search for libiconv in includedir and libdir
@@ -1541,6 +1547,10 @@ Some influential environment variables:
   YFLAGS      The list of arguments that will be passed by default to $YACC.
               This script will default YFLAGS to the empty string to avoid a
               default value of `-d' given by some make applications.
+  MSGPACK_CFLAGS
+              C compiler flags for MSGPACK, overriding pkg-config
+  MSGPACK_LIBS
+              linker flags for MSGPACK, overriding pkg-config
 
 Use these variables to override the choices made by `configure' or to help
 it to find libraries and programs with nonstandard names/locations.
@@ -10971,7 +10981,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 10974 "configure"
+#line 10984 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11077,7 +11087,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11080 "configure"
+#line 11090 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -13723,6 +13733,127 @@ $as_echo "#define USE_BINARY_FOPEN 1" >>confdefs.h
  ;;
 esac
 
+# Support for the msgpack C library.
+
+# Check whether --with-msgpack was given.
+if test "${with_msgpack+set}" = set; then :
+  withval=$with_msgpack;
+else
+  with_msgpack=auto
+fi
+
+
+
+if test "$with_msgpack" != no; then
+
+pkg_failed=no
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for msgpack" >&5
+$as_echo_n "checking for msgpack... " >&6; }
+
+if test -n "$MSGPACK_CFLAGS"; then
+    pkg_cv_MSGPACK_CFLAGS="$MSGPACK_CFLAGS"
+ elif test -n "$PKG_CONFIG"; then
+    if test -n "$PKG_CONFIG" && \
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"msgpack\""; } >&5
+  ($PKG_CONFIG --exists --print-errors "msgpack") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; then
+  pkg_cv_MSGPACK_CFLAGS=`$PKG_CONFIG --cflags "msgpack" 2>/dev/null`
+		      test "x$?" != "x0" && pkg_failed=yes
+else
+  pkg_failed=yes
+fi
+ else
+    pkg_failed=untried
+fi
+if test -n "$MSGPACK_LIBS"; then
+    pkg_cv_MSGPACK_LIBS="$MSGPACK_LIBS"
+ elif test -n "$PKG_CONFIG"; then
+    if test -n "$PKG_CONFIG" && \
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"msgpack\""; } >&5
+  ($PKG_CONFIG --exists --print-errors "msgpack") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; then
+  pkg_cv_MSGPACK_LIBS=`$PKG_CONFIG --libs "msgpack" 2>/dev/null`
+		      test "x$?" != "x0" && pkg_failed=yes
+else
+  pkg_failed=yes
+fi
+ else
+    pkg_failed=untried
+fi
+
+if test $pkg_failed = no; then
+  pkg_save_LDFLAGS="$LDFLAGS"
+  LDFLAGS="$LDFLAGS $pkg_cv_MSGPACK_LIBS"
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+
+else
+  pkg_failed=yes
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+  LDFLAGS=$pkg_save_LDFLAGS
+fi
+
+
+
+if test $pkg_failed = yes; then
+        { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+
+if $PKG_CONFIG --atleast-pkgconfig-version 0.20; then
+        _pkg_short_errors_supported=yes
+else
+        _pkg_short_errors_supported=no
+fi
+        if test $_pkg_short_errors_supported = yes; then
+	        MSGPACK_PKG_ERRORS=`$PKG_CONFIG --short-errors --print-errors --cflags --libs "msgpack" 2>&1`
+        else
+	        MSGPACK_PKG_ERRORS=`$PKG_CONFIG --print-errors --cflags --libs "msgpack" 2>&1`
+        fi
+	# Put the nasty error message in config.log where it belongs
+	echo "$MSGPACK_PKG_ERRORS" >&5
+
+
+      if test "$with_msgpack" = yes; then
+	as_fn_error $? "--with-msgpack was given, but msgpack is missing or unusable." "$LINENO" 5
+      fi
+
+elif test $pkg_failed = untried; then
+        { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+
+      if test "$with_msgpack" = yes; then
+	as_fn_error $? "--with-msgpack was given, but msgpack is missing or unusable." "$LINENO" 5
+      fi
+
+else
+	MSGPACK_CFLAGS=$pkg_cv_MSGPACK_CFLAGS
+	MSGPACK_LIBS=$pkg_cv_MSGPACK_LIBS
+        { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+
+
+$as_echo "#define HAVE_MSGPACK 1" >>confdefs.h
+
+
+fi
+fi
+
 # target-specific stuff:
 
 # Canonicalize the secondary target names.