Add --compress-debug-sections=[none|zlib|zlib-gnu|zlib-gabi]

This patch adds --compress-debug-sections=[none|zlib|zlib-gnu|zlib-gabi]
to ld for ELF targets to support generating compressed DWARF debug
sections.  We always generate .zdebug_* section since section names have
been finalized and they can't be changed easily when compression is
being performed.

bfd/

	* bfd-in.h (compressed_debug_section_type): New.
	* compress.c (bfd_compress_section_contents): Add an argument
	for linker write compression and always generate .zdebug_*
	section when linking.
	(bfd_init_section_compress_status): Pass FALSE to
	bfd_compress_section_contents.
	(bfd_compress_section): New function.
	* elf.c (elf_fake_sections): For linking, set SEC_ELF_COMPRESS
	on DWARF debug sections if COMPRESS_DEBUG is set and rename
	section if COMPRESS_DEBUG_GABI_ZLIB isn't set.
	(assign_file_positions_for_non_load_sections): Set sh_offset
	to -1 if SEC_ELF_COMPRESS is set.
	(assign_file_positions_except_relocs): Likwise.
	(_bfd_elf_assign_file_positions_for_relocs): Renamed to ...
	(_bfd_elf_assign_file_positions_for_non_load): This.  Change
	return time to bfd_boolean.  Compress the section if
	SEC_ELF_COMPRESS is set.
	(_bfd_elf_write_object_contents): Updated.
	(_bfd_elf_set_section_contents): Write section contents to
	the buffer if SEC_ELF_COMPRESS is set.
	* merge.c: Include "elf-bfd.h".
	(sec_merge_emit): Add arguments for contents and offset.  Write
	to contents with offset if contents isn't NULL.
	(_bfd_write_merged_section): Write section contents to the
	buffer if SEC_ELF_COMPRESS is set.  Pass contents and
	output_offset to sec_merge_emit.
	* elflink.c (bfd_elf_final_link): Allocate the buffer for
	output section contents if SEC_ELF_COMPRESS is set.
	* section.c (SEC_ELF_COMPRESS): New.
	* bfd-in2.h: Regenerated.

gas/

	* as.h (compressed_debug_section_type): Removed.

include/

	* bfdlink.h (bfd_link_info): Add compress_debug.

ld/

	* ld.texinfo: Document --compress-debug-sections=.
	* ldmain.c (main): Set BFD_COMPRESS on output_bfd if
	COMPRESS_DEBUG is set.  Set BFD_COMPRESS_GABI on output_bfd
	for COMPRESS_DEBUG_GABI_ZLIB.
	* lexsup.c (elf_static_list_options): Add
	--compress-debug-sections=.
	* emultempl/elf32.em (OPTION_COMPRESS_DEBUG): New.
	(xtra_long): Add "compress-debug-sections".
	(gld${EMULATION_NAME}_handle_option): Handle
	OPTION_COMPRESS_DEBUG.

ld/testsuite/

	* ld-elf/compress.exp (build_tests): Add tests for
	--compress-debug-sections=.
	(run_tests): Likewise.
	Add additonal tests for --compress-debug-sections=.
	* ld-elf/gabiend.rt: New file.
	* ld-elf/gabinormal.rt: Likewise.
	* ld-elf/gnubegin.rS: Likewise.
	* ld-elf/gnunormal.rS: Likewise.
	* ld-elf/zlibbegin.rS: Likewise.
	* ld-elf/zlibnormal.rS: Likewise.

13 files changed, 253 insertions, 1 deletions

diff --git a/ld/ChangeLog b/ld/ChangeLog
index 3e944fe..bad213b 100644
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,5 +1,18 @@
 2015-04-14  H.J. Lu  <hongjiu.lu@intel.com>
 
+	* ld.texinfo: Document --compress-debug-sections=.
+	* ldmain.c (main): Set BFD_COMPRESS on output_bfd if
+	COMPRESS_DEBUG is set.  Set BFD_COMPRESS_GABI on output_bfd
+	for COMPRESS_DEBUG_GABI_ZLIB.
+	* lexsup.c (elf_static_list_options): Add
+	--compress-debug-sections=.
+	* emultempl/elf32.em (OPTION_COMPRESS_DEBUG): New.
+	(xtra_long): Add "compress-debug-sections".
+	(gld${EMULATION_NAME}_handle_option): Handle
+	OPTION_COMPRESS_DEBUG.
+
+2015-04-14  H.J. Lu  <hongjiu.lu@intel.com>
+
 	PR ld/pr17709
 	* ld.texinfo: Document "-z noextern-protected-data".
 	* ldmain.c (main): Initialize link_info.extern_protected_data
diff --git a/ld/emultempl/elf32.em b/ld/emultempl/elf32.em
index 5db5a93..0802d76 100644
--- a/ld/emultempl/elf32.em
+++ b/ld/emultempl/elf32.em
@@ -2110,6 +2110,7 @@ fragment <<EOF
 #define OPTION_HASH_STYLE		(OPTION_EXCLUDE_LIBS + 1)
 #define OPTION_BUILD_ID			(OPTION_HASH_STYLE + 1)
 #define OPTION_AUDIT			(OPTION_BUILD_ID + 1)
+#define OPTION_COMPRESS_DEBUG		(OPTION_AUDIT + 1)
 
 static void
 gld${EMULATION_NAME}_add_options
@@ -2137,6 +2138,7 @@ EOF
 fi
 fragment <<EOF
     {"build-id", optional_argument, NULL, OPTION_BUILD_ID},
+    {"compress-debug-sections", required_argument, NULL, OPTION_COMPRESS_DEBUG},
 EOF
 if test x"$GENERATE_SHLIB_SCRIPT" = xyes; then
 fragment <<EOF
@@ -2186,6 +2188,19 @@ gld${EMULATION_NAME}_handle_option (int optc)
 	emit_note_gnu_build_id = xstrdup (optarg);
       break;
 
+    case OPTION_COMPRESS_DEBUG:
+      if (strcasecmp (optarg, "none") == 0)
+	link_info.compress_debug = COMPRESS_DEBUG_NONE;
+      else if (strcasecmp (optarg, "zlib") == 0)
+	link_info.compress_debug = COMPRESS_DEBUG_ZLIB;
+      else if (strcasecmp (optarg, "zlib-gnu") == 0)
+	link_info.compress_debug = COMPRESS_DEBUG_GNU_ZLIB;
+      else if (strcasecmp (optarg, "zlib-gabi") == 0)
+	link_info.compress_debug = COMPRESS_DEBUG_GABI_ZLIB;
+      else
+	einfo (_("%P%F: invalid --compress-debug-sections option: \`%s'\n"),
+	       optarg);
+      break;
 EOF
 
 if test x"$GENERATE_SHLIB_SCRIPT" = xyes; then
diff --git a/ld/ld.texinfo b/ld/ld.texinfo
index 4348c88..77c02d6 100644
--- a/ld/ld.texinfo
+++ b/ld/ld.texinfo
@@ -2201,6 +2201,22 @@ new style GNU @code{.gnu.hash} section or @code{both} for both
 the classic ELF @code{.hash} and new style GNU @code{.gnu.hash}
 hash tables.  The default is @code{sysv}.
 
+@kindex --compress-debug-sections=none
+@kindex --compress-debug-sections=zlib
+@kindex --compress-debug-sections=zlib-gnu
+@kindex --compress-debug-sections=zlib-gabi
+@item --compress-debug-sections=none
+@itemx --compress-debug-sections=zlib
+@itemx --compress-debug-sections=zlib-gnu
+@itemx --compress-debug-sections=zlib-gabi
+On ELF platforms , these options control how DWARF debug sections are
+compressed using zlib.  @option{--compress-debug-sections=none} doesn't
+compress DWARF debug sections.  @option{--compress-debug-sections=zlib}
+and @option{--compress-debug-sections=zlib-gnu} compress DWARF debug
+sections and rename debug section names to begin with @samp{.zdebug}
+instead of @samp{.debug}.  @option{--compress-debug-sections=zlib-gabi}
+compresses DWARF debug sections with SHF_COMPRESSED from the ELF ABI.
+
 @kindex --reduce-memory-overheads
 @item --reduce-memory-overheads
 This option reduces memory requirements at ld runtime, at the expense of
diff --git a/ld/ldmain.c b/ld/ldmain.c
index 2ecb92d..a7b72bd 100644
--- a/ld/ldmain.c
+++ b/ld/ldmain.c
@@ -425,6 +425,13 @@ main (int argc, char **argv)
   else
     link_info.output_bfd->flags |= EXEC_P;
 
+  if ((link_info.compress_debug & COMPRESS_DEBUG))
+    {
+      link_info.output_bfd->flags |= BFD_COMPRESS;
+      if (link_info.compress_debug == COMPRESS_DEBUG_GABI_ZLIB)
+	link_info.output_bfd->flags |= BFD_COMPRESS_GABI;
+    }
+
   ldwrite ();
 
   if (config.map_file != NULL)
diff --git a/ld/lexsup.c b/ld/lexsup.c
index 4a71ba4..b618241 100644
--- a/ld/lexsup.c
+++ b/ld/lexsup.c
@@ -1722,6 +1722,9 @@ elf_static_list_options (FILE *file)
   fprintf (file, _("\
   --build-id[=STYLE]          Generate build ID note\n"));
   fprintf (file, _("\
+  --compress-debug-sections=[none|zlib|zlib-gnu|zlib-gabi]\n\
+                              Compress DWARF debug sections using zlib\n"));
+  fprintf (file, _("\
   -z common-page-size=SIZE    Set common page size to SIZE\n"));
   fprintf (file, _("\
   -z max-page-size=SIZE       Set maximum page size to SIZE\n"));
diff --git a/ld/testsuite/ChangeLog b/ld/testsuite/ChangeLog
index c2ed134..54ae0ae 100644
--- a/ld/testsuite/ChangeLog
+++ b/ld/testsuite/ChangeLog
@@ -1,3 +1,16 @@
+2015-04-14  H.J. Lu  <hongjiu.lu@intel.com>
+
+	* ld-elf/compress.exp (build_tests): Add tests for
+	--compress-debug-sections=.
+	(run_tests): Likewise.
+	Add additonal tests for --compress-debug-sections=.
+	* ld-elf/gabiend.rt: New file.
+	* ld-elf/gabinormal.rt: Likewise.
+	* ld-elf/gnubegin.rS: Likewise.
+	* ld-elf/gnunormal.rS: Likewise.
+	* ld-elf/zlibbegin.rS: Likewise.
+	* ld-elf/zlibnormal.rS: Likewise.
+
 2015-04-15  Alan Modra  <amodra@gmail.com>
 
 	* ld-gc/pr18223.d: xfail tic6x.
diff --git a/ld/testsuite/ld-elf/compress.exp b/ld/testsuite/ld-elf/compress.exp
index adb7fc2..e2448b9 100644
--- a/ld/testsuite/ld-elf/compress.exp
+++ b/ld/testsuite/ld-elf/compress.exp
@@ -49,7 +49,8 @@ set build_tests {
    "-shared" "-fPIC -g -Wa,--compress-debug-sections"
    {foo.c} {} "libfoo.so"}
   {"Build libbar.so with compressed debug sections"
-   "-shared" "-fPIC -g -Wa,--compress-debug-sections"
+   "-shared -Wl,--compress-debug-sections=none"
+   "-fPIC -g -Wa,--compress-debug-sections"
    {begin.c end.c} {} "libbar.so"}
   {"Build libfoozlib.so with compressed debug sections with zlib-gabi"
    "-shared" "-fPIC -g -Wa,--compress-debug-sections=zlib-gabi"
@@ -57,6 +58,30 @@ set build_tests {
   {"Build libbarzlib.so with compressed debug sections with zlib-gabi"
    "-shared" "-fPIC -g -Wa,--compress-debug-sections=zlib-gabi"
    {begin.c end.c} {} "libbarzlib.so"}
+  {"Build libzlibfoo.so with zlib compressed debug sections"
+   "-shared -Wl,--compress-debug-sections=zlib"
+   "-fPIC -g -Wa,--compress-debug-sections=zlib"
+   {foo.c} {} "libzlibfoo.so"}
+  {"Build libgnufoo.so with zlib-gnu compressed debug sections"
+   "-shared -Wl,--compress-debug-sections=zlib-gnu"
+   "-fPIC -g -Wa,--compress-debug-sections=zlib-gnu"
+   {foo.c} {} "libgnufoo.so"}
+  {"Build libgabifoo.so with zlib-gabi compressed debug sections"
+   "-shared -Wl,--compress-debug-sections=zlib-gabi"
+   "-fPIC -g -Wa,--compress-debug-sections=zlib-gabi"
+   {foo.c} {} "libgabifoo.so"}
+  {"Build zlibbegin.o with zlib compressed debug sections"
+   "-r -nostdlib -Wl,--compress-debug-sections=zlib"
+   "-g -Wa,--compress-debug-sections=zlib"
+   {begin.c} {} "zlibbegin.o"}
+  {"Build gnubegin.o with zlib-gnu compressed debug sections"
+   "-r -nostdlib -Wl,--compress-debug-sections=zlib-gnu"
+   "-g -Wa,--compress-debug-sections=zlib-gnu"
+   {begin.c} {} "gnubegin.o"}
+  {"Build gabiend.o with zlib-gabi compressed debug sections"
+   "-r -nostdlib -Wl,--compress-debug-sections=zlib-gabi"
+   "-g -Wa,--compress-debug-sections=zlib-gnu"
+   {end.c} {} "gabiend.o"}
 }
 
 set run_tests {
@@ -66,6 +91,15 @@ set run_tests {
     {"Run normal with libfoo.so with compressed debug sections with zlib-gabi"
      "tmpdir/begin.o tmpdir/libfoozlib.so tmpdir/end.o" ""
      {main.c} "normal" "normal.out" "-Wa,--compress-debug-sections=zlib-gabi"}
+    {"Run zlibnormal with libzlibfoo.so with zlib compressed debug sections"
+     "tmpdir/begin.o tmpdir/libzlibfoo.so tmpdir/end.o --compress-debug-sections=zlib" ""
+     {main.c} "zlibnormal" "normal.out" "-Wa,--compress-debug-sections=zlib"}
+    {"Run gnunormal with libgnufoo.so with zlib-gnu compressed debug sections"
+     "tmpdir/gnubegin.o tmpdir/libgnufoo.so tmpdir/end.o --compress-debug-sections=zlib-gnu" ""
+     {main.c} "gnunormal" "normal.out" "-Wa,--compress-debug-sections=zlib-gnu"}
+    {"Run gabinormal with libgabifoo.so with zlib-gabi compressed debug sections"
+     "tmpdir/zlibbegin.o tmpdir/libgabifoo.so tmpdir/gabiend.o --compress-debug-sections=zlib-gabi" ""
+     {main.c} "gabinormal" "normal.out" "-Wa,--compress-debug-sections=zlib-gabi"}
 }
 
 run_cc_link_tests $build_tests
@@ -79,3 +113,134 @@ if { [catch {exec cmp tmpdir/libfoo.so tmpdir/libfoozlib.so}] } then {
 } else {
     pass "$test_name"
 }
+
+global READELF
+
+set test_name "Link -r with zlib compressed debug output"
+set test zlibbegin
+send_log "$READELF -S -W tmpdir/$test.o > tmpdir/$test.out\n"
+set got [remote_exec host "$READELF -S -W tmpdir/$test.o" "" "/dev/null" "tmpdir/$test.out"]
+if { [lindex $got 0] != 0 || ![string match "" [lindex $got 1]] } then {
+    send_log "$got\n"
+    unresolved "$test_name"
+}
+if { [regexp_diff tmpdir/$test.out $srcdir/$subdir/$test.rS] } then {
+    fail "$test_name"
+} else {
+    pass "$test_name"
+}
+
+set test_name "Link -r with zlib-gnu compressed debug output"
+set test gnubegin
+send_log "$READELF -S -W tmpdir/$test.o > tmpdir/$test.out\n"
+set got [remote_exec host "$READELF -S -W tmpdir/$test.o" "" "/dev/null" "tmpdir/$test.out"]
+if { [lindex $got 0] != 0 || ![string match "" [lindex $got 1]] } then {
+    send_log "$got\n"
+    unresolved "$test_name"
+}
+if { [regexp_diff tmpdir/$test.out $srcdir/$subdir/$test.rS] } then {
+    fail "$test_name"
+} else {
+    pass "$test_name"
+}
+
+set test_name "Link -r with zlib-gabi compressed debug output"
+set test gabiend
+send_log "$READELF -t -W tmpdir/$test.o > tmpdir/$test.out\n"
+set got [remote_exec host "$READELF -t -W tmpdir/$test.o" "" "/dev/null" "tmpdir/$test.out"]
+if { [lindex $got 0] != 0 || ![string match "" [lindex $got 1]] } then {
+    send_log "$got\n"
+    unresolved "$test_name"
+}
+if { [regexp_diff tmpdir/$test.out $srcdir/$subdir/$test.rt] } then {
+    fail "$test_name"
+} else {
+    pass "$test_name"
+}
+
+set test_name "Link with zlib compressed debug output"
+set test normal
+send_log "$READELF -w tmpdir/$test > tmpdir/$test.out\n"
+set got [remote_exec host "$READELF -w tmpdir/$test" "" "/dev/null" "tmpdir/$test.out"]
+if { [lindex $got 0] != 0 || ![string match "" [lindex $got 1]] } then {
+    send_log "$got\n"
+    unresolved "$test_name"
+}
+
+set test_name "Link with zlib compressed debug output"
+set test zlibnormal
+send_log "$READELF -w tmpdir/$test | sed -e \"s/.zdebug_/.debug_/\" > tmpdir/$test.out\n"
+set got [remote_exec host "$READELF -w tmpdir/$test | sed -e \"s/.zdebug_/.debug_/\"" "" "/dev/null" "tmpdir/$test.out"]
+if { [lindex $got 0] != 0 || ![string match "" [lindex $got 1]] } then {
+    send_log "$got\n"
+    unresolved "$test_name"
+}
+if { [catch {exec cmp tmpdir/normal.out tmpdir/$test.out}] } then {
+    send_log "tmpdir/normal.out tmpdir/$test.out differ.\n"
+    fail "$test_name"
+} else {
+    pass "$test_name"
+}
+send_log "$READELF -S -W tmpdir/$test' > tmpdir/$test.out\n"
+set got [remote_exec host "$READELF -S -W tmpdir/$test" "" "/dev/null" "tmpdir/$test.out"]
+if { [lindex $got 0] != 0 || ![string match "" [lindex $got 1]] } then {
+    send_log "$got\n"
+    unresolved "$test_name"
+}
+if { [regexp_diff tmpdir/$test.out $srcdir/$subdir/$test.rS] } then {
+    fail "$test_name"
+} else {
+    pass "$test_name"
+}
+
+set test_name "Link with zlib-gnu compressed debug output"
+set test gnunormal
+send_log "$READELF -w tmpdir/$test | sed -e \"s/.zdebug_/.debug_/\" > tmpdir/$test.out\n"
+set got [remote_exec host "$READELF -w tmpdir/$test | sed -e \"s/.zdebug_/.debug_/\"" "" "/dev/null" "tmpdir/$test.out"]
+if { [lindex $got 0] != 0 || ![string match "" [lindex $got 1]] } then {
+    send_log "$got\n"
+    unresolved "$test_name"
+}
+if { [catch {exec cmp tmpdir/normal.out tmpdir/$test.out}] } then {
+    send_log "tmpdir/normal.out tmpdir/$test.out differ.\n"
+    fail "$test_name"
+} else {
+    pass "$test_name"
+}
+send_log "$READELF -S -W tmpdir/$test' > tmpdir/$test.out\n"
+set got [remote_exec host "$READELF -S -W tmpdir/$test" "" "/dev/null" "tmpdir/$test.out"]
+if { [lindex $got 0] != 0 || ![string match "" [lindex $got 1]] } then {
+    send_log "$got\n"
+    unresolved "$test_name"
+}
+if { [regexp_diff tmpdir/$test.out $srcdir/$subdir/$test.rS] } then {
+    fail "$test_name"
+} else {
+    pass "$test_name"
+}
+
+set test gabinormal
+set test_name "Link with zlib-gabi compressed debug output"
+send_log "$READELF -w tmpdir/$test > tmpdir/$test.out\n"
+set got [remote_exec host "$READELF -w tmpdir/$test" "" "/dev/null" "tmpdir/$test.out"]
+if { [lindex $got 0] != 0 || ![string match "" [lindex $got 1]] } then {
+    send_log "$got\n"
+    unresolved "$test_name"
+}
+if { [catch {exec cmp tmpdir/normal.out tmpdir/$test.out}] } then {
+    send_log "tmpdir/normal.out tmpdir/$test.out differ.\n"
+    fail "$test_name"
+} else {
+    pass "$test_name"
+}
+send_log "$READELF -t -W tmpdir/$test > tmpdir/$test.out\n"
+set got [remote_exec host "$READELF -t -W tmpdir/$test" "" "/dev/null" "tmpdir/$test.out"]
+if { [lindex $got 0] != 0 || ![string match "" [lindex $got 1]] } then {
+    send_log "$got\n"
+    unresolved "$test_name"
+}
+if { [regexp_diff tmpdir/$test.out $srcdir/$subdir/$test.rt] } then {
+    fail "$test_name"
+} else {
+    pass "$test_name"
+}
diff --git a/ld/testsuite/ld-elf/gabiend.rt b/ld/testsuite/ld-elf/gabiend.rt
new file mode 100644
index 0000000..23bc36c
--- /dev/null
+++ b/ld/testsuite/ld-elf/gabiend.rt
@@ -0,0 +1,4 @@
+#...
+ +\[[0-9a-f]+\]: .*COMPRESSED
+ +ZLIB, [0-9a-f]+, 1
+#pass
diff --git a/ld/testsuite/ld-elf/gabinormal.rt b/ld/testsuite/ld-elf/gabinormal.rt
new file mode 100644
index 0000000..23bc36c
--- /dev/null
+++ b/ld/testsuite/ld-elf/gabinormal.rt
@@ -0,0 +1,4 @@
+#...
+ +\[[0-9a-f]+\]: .*COMPRESSED
+ +ZLIB, [0-9a-f]+, 1
+#pass
diff --git a/ld/testsuite/ld-elf/gnubegin.rS b/ld/testsuite/ld-elf/gnubegin.rS
new file mode 100644
index 0000000..54de24c
--- /dev/null
+++ b/ld/testsuite/ld-elf/gnubegin.rS
@@ -0,0 +1,3 @@
+#...
+ +\[[ 0-9]+\] .zdebug_.* +(PROGBITS|MIPS_DWARF) +0+ +[0-9a-f]+ +[0-9a-f]+ [0-9a-f]+ +0 +0 +1
+#pass
diff --git a/ld/testsuite/ld-elf/gnunormal.rS b/ld/testsuite/ld-elf/gnunormal.rS
new file mode 100644
index 0000000..54de24c
--- /dev/null
+++ b/ld/testsuite/ld-elf/gnunormal.rS
@@ -0,0 +1,3 @@
+#...
+ +\[[ 0-9]+\] .zdebug_.* +(PROGBITS|MIPS_DWARF) +0+ +[0-9a-f]+ +[0-9a-f]+ [0-9a-f]+ +0 +0 +1
+#pass
diff --git a/ld/testsuite/ld-elf/zlibbegin.rS b/ld/testsuite/ld-elf/zlibbegin.rS
new file mode 100644
index 0000000..54de24c
--- /dev/null
+++ b/ld/testsuite/ld-elf/zlibbegin.rS
@@ -0,0 +1,3 @@
+#...
+ +\[[ 0-9]+\] .zdebug_.* +(PROGBITS|MIPS_DWARF) +0+ +[0-9a-f]+ +[0-9a-f]+ [0-9a-f]+ +0 +0 +1
+#pass
diff --git a/ld/testsuite/ld-elf/zlibnormal.rS b/ld/testsuite/ld-elf/zlibnormal.rS
new file mode 100644
index 0000000..54de24c
--- /dev/null
+++ b/ld/testsuite/ld-elf/zlibnormal.rS
@@ -0,0 +1,3 @@
+#...
+ +\[[ 0-9]+\] .zdebug_.* +(PROGBITS|MIPS_DWARF) +0+ +[0-9a-f]+ +[0-9a-f]+ [0-9a-f]+ +0 +0 +1
+#pass