ld/x86: Add -z report-relative-reloc

Linker generated relative relocations don't have symbol info:

[hjl@gnu-cfl-2 tmpdir]$ readelf -rW dump

Relocation section '.rela.dyn' at offset 0x180 contains 2 entries:
 Offset     Info    Type                Sym. Value  Symbol's Name + Addend
00002f70  00000008 R_X86_64_RELATIVE                 1000
00002f68  00000025 R_X86_64_IRELATIVE                1007
[hjl@gnu-cfl-2 tmpdir]$

Add -z report-relative-reloc to x86 ELF linker to report dynamic relative
relocations:

[hjl@gnu-cfl-2 tmpdir]$ ../ld-new -pie -melf32_x86_64 -z report-relative-reloc -o dump report-reloc-1.o
dump: R_X86_64_IRELATIVE (offset: 0x00002f68, info: 0x00000025, addend: 0x00001007) against 'ifunc' for section '.data.rel.ro.local' in report-reloc-1.o
dump: R_X86_64_RELATIVE (offset: 0x00002f70, info: 0x00000008, addend: 0x00001000) against '_start' for section '.data.rel.ro.local' in report-reloc-1.o
[hjl@gnu-cfl-2 tmpdir]$

It can be used to map relative relocations to corresponding symbols.

bfd/

	* elf-linker-x86.h (elf_linker_x86_params): Add
	report_relative_reloc.
	* elf32-i386.c (elf_i386_relocate_section): Call
	_bfd_x86_elf_link_report_relative_reloc to report relative
	relocations for -z report-relative-reloc.
	(elf_i386_finish_dynamic_symbol): Likewse.
	* elf64-x86-64.c (elf_x86_64_relocate_section): Likewse.
	(elf_x86_64_finish_dynamic_symbol): Likewse.
	* elfxx-x86.c (_bfd_x86_elf_link_report_relative_reloc): New
	function.
	* elfxx-x86.h (_bfd_x86_elf_link_report_relative_reloc): New
	prototype.

ld/

	* NEWS: Mention -z report-relative-reloc.
	* ld.texi: Document -z report-relative-reloc.
	* emulparams/elf32_x86_64.sh: Source x86-report-relative.sh.
	* emulparams/elf_i386.sh: Likewse.
	* emulparams/elf_x86_64.sh: Likewse.
	* emulparams/x86-report-relative.sh: New file.
	* testsuite/ld-i386/report-reloc-1.d: Likewse.
	* testsuite/ld-i386/report-reloc-1.l: Likewse.
	* testsuite/ld-i386/report-reloc-1.s: Likewse.
	* testsuite/ld-x86-64/report-reloc-1-x32.d: Likewse.
	* testsuite/ld-x86-64/report-reloc-1.d: Likewse.
	* testsuite/ld-x86-64/report-reloc-1.l: Likewse.
	* testsuite/ld-x86-64/report-reloc-1.s: Likewse.
	* testsuite/ld-i386/i386.exp: Run report-reloc-1.
	* testsuite/ld-x86-64/x86-64.exp: Run report-reloc-1 and
	report-reloc-1-x32.

4 files changed, 25 insertions, 0 deletions

diff --git a/ld/testsuite/ld-i386/i386.exp b/ld/testsuite/ld-i386/i386.exp
index 655f83df53a..f3e62a4151e 100644
--- a/ld/testsuite/ld-i386/i386.exp
+++ b/ld/testsuite/ld-i386/i386.exp
@@ -506,6 +506,7 @@ run_dump_test "pr18815"
 run_dump_test "pr19939a"
 run_dump_test "pr19939b"
 run_dump_test "tlsdesc2"
+run_dump_test "report-reloc-1"
 
 proc undefined_weak {cflags ldflags} {
     set testname "Undefined weak symbol"
diff --git a/ld/testsuite/ld-i386/report-reloc-1.d b/ld/testsuite/ld-i386/report-reloc-1.d
new file mode 100644
index 00000000000..51fbbd8d105
--- /dev/null
+++ b/ld/testsuite/ld-i386/report-reloc-1.d
@@ -0,0 +1,10 @@
+#source: report-reloc-1.s
+#as: --32
+#ld: -pie -melf_i386 -z report-relative-reloc
+#warning_output: report-reloc-1.l
+#readelf: -r --wide
+
+Relocation section '.rel.dyn' at offset 0x[0-9a-f]+ contains 2 entries:
+ +Offset +Info +Type +Sym.* Value +Symbol's Name
+[0-9a-f]+ +[0-9a-f]+ +R_386_RELATIVE +
+[0-9a-f]+ +[0-9a-f]+ +R_386_IRELATIVE +
diff --git a/ld/testsuite/ld-i386/report-reloc-1.l b/ld/testsuite/ld-i386/report-reloc-1.l
new file mode 100644
index 00000000000..a0293bc4f96
--- /dev/null
+++ b/ld/testsuite/ld-i386/report-reloc-1.l
@@ -0,0 +1,2 @@
+tmpdir/dump: R_386_IRELATIVE \(offset: 0x0+2000, info: 0x0+2a\) against 'ifunc' for section '.data.rel.ro.local' in tmpdir/report-reloc-1.o
+tmpdir/dump: R_386_RELATIVE \(offset: 0x0+2004, info: 0x0+8\) against '_start' for section '.data.rel.ro.local' in tmpdir/report-reloc-1.o
diff --git a/ld/testsuite/ld-i386/report-reloc-1.s b/ld/testsuite/ld-i386/report-reloc-1.s
new file mode 100644
index 00000000000..689cb690a80
--- /dev/null
+++ b/ld/testsuite/ld-i386/report-reloc-1.s
@@ -0,0 +1,12 @@
+	.text
+	.globl _start
+	.type ifunc, @gnu_indirect_function
+_start:
+	lea	.Ljmp@GOTOFF(%ebx), %eax
+ifunc:
+	jmp	*(%eax)
+	.section	.data.rel.ro.local,"aw",@progbits
+	.align	4
+.Ljmp:
+	.long ifunc
+	.long _start