x86: Remove the unused _GLOBAL_OFFSET_TABLE_

Since _GLOBAL_OFFSET_TABLE_ may be referenced implicitly on x86,
checking ref_regular_nonweak leaves the unused _GLOBAL_OFFSET_TABLE_
in output.  This patch checks explicit GOT references instead.

ld-i386/discarded1.s and ld-x86-64/discarded1.s are updated to avoid
linker optimization which removes GOT references.

bfd/

	PR ld/22782
	* elf32-i386.c (elf_i386_check_relocs): Set got_referenced if
	_GLOBAL_OFFSET_TABLE_ is referenced or GOT is needed to resolve
	undefined weak symbol to 0.
	* elf64-x86-64.c (elf_x86_64_check_relocs): Set got_referenced
	if _GLOBAL_OFFSET_TABLE_ is referenced.
	* elfxx-x86.c (_bfd_x86_elf_size_dynamic_sections): Check
	got_referenced instead of ref_regular_nonweak.  Remove the
	unused _GLOBAL_OFFSET_TABLE_ from symbol table.
	* elfxx-x86.h (elf_x86_link_hash_table): Add got_referenced.

ld/

	PR ld/22782
	* testsuite/ld-i386/discarded1.s: Replace mov with div.
	* testsuite/ld-x86-64/discarded1.s: Likewise.
	* testsuite/ld-i386/i386.exp: Run pr22782.
	* testsuite/ld-i386/load1-nacl.d: Updated for removing
	_GLOBAL_OFFSET_TABLE_ from output.
	* testsuite/ld-i386/load1.d: Likewise.
	* testsuite/ld-x86-64/load1a-nacl.d: Likewise.
	* testsuite/ld-x86-64/load1a.d: Likewise.
	* testsuite/ld-x86-64/load1b-nacl.d: Likewise.
	* testsuite/ld-x86-64/load1b.d: Likewise.
	* testsuite/ld-i386/pr22782.d: New file.
	* testsuite/ld-i386/pr22782.s: Likewise.
	* testsuite/ld-x86-64/pr22782.s: Likewise.
	* testsuite/ld-x86-64/pr22782a.d: Likewise.
	* testsuite/ld-x86-64/pr22782b.d: Likewise.
	* testsuite/ld-x86-64/x86-64.exp: Run pr22782a and pr22782b.

6 files changed, 111 insertions, 85 deletions

diff --git a/ld/testsuite/ld-i386/discarded1.s b/ld/testsuite/ld-i386/discarded1.s
index 9b20c87..21e5cb7 100644
--- a/ld/testsuite/ld-i386/discarded1.s
+++ b/ld/testsuite/ld-i386/discarded1.s
@@ -2,7 +2,7 @@
 .globl _start
 	.type	_start, @function
 _start:
-	movl	x@GOT(%ecx), %eax
+	divl	x@GOT(%ecx), %eax
 	.size	_start, .-_start
 .globl x
 	.data
diff --git a/ld/testsuite/ld-i386/i386.exp b/ld/testsuite/ld-i386/i386.exp
index c4fc545..e4ec07d 100644
--- a/ld/testsuite/ld-i386/i386.exp
+++ b/ld/testsuite/ld-i386/i386.exp
@@ -450,6 +450,7 @@ run_dump_test "pr22115-1b"
 run_dump_test "pr22115-1c"
 run_dump_test "pr22115-1d"
 run_dump_test "pr22135"
+run_dump_test "pr22782"
 
 if { !([istarget "i?86-*-linux*"]
        || [istarget "i?86-*-gnu*"]
diff --git a/ld/testsuite/ld-i386/load1-nacl.d b/ld/testsuite/ld-i386/load1-nacl.d
index 1dbba11..317d1c4 100644
--- a/ld/testsuite/ld-i386/load1-nacl.d
+++ b/ld/testsuite/ld-i386/load1-nacl.d
@@ -8,52 +8,52 @@
 
 SYMBOL TABLE:
 #...
-10030080 l     O .data	0+1 bar
+10030074 l     O .data	0+1 bar
 #...
-10030081 g     O .data	0+1 foo
+10030075 g     O .data	0+1 foo
 #...
 
 Disassembly of section .text:
 
 0+20000 <_start>:
-[ 	]*[a-f0-9]+:	c7 c0 80 00 03 10    	mov    \$0x10030080,%eax
-[ 	]*[a-f0-9]+:	81 d0 80 00 03 10    	adc    \$0x10030080,%eax
-[ 	]*[a-f0-9]+:	81 c3 80 00 03 10    	add    \$0x10030080,%ebx
-[ 	]*[a-f0-9]+:	81 e1 80 00 03 10    	and    \$0x10030080,%ecx
-[ 	]*[a-f0-9]+:	81 fa 80 00 03 10    	cmp    \$0x10030080,%edx
-[ 	]*[a-f0-9]+:	81 cf 80 00 03 10    	or     \$0x10030080,%edi
-[ 	]*[a-f0-9]+:	81 de 80 00 03 10    	sbb    \$0x10030080,%esi
-[ 	]*[a-f0-9]+:	81 ed 80 00 03 10    	sub    \$0x10030080,%ebp
-[ 	]*[a-f0-9]+:	81 f4 80 00 03 10    	xor    \$0x10030080,%esp
-[ 	]*[a-f0-9]+:	f7 c1 80 00 03 10    	test   \$0x10030080,%ecx
-[ 	]*[a-f0-9]+:	c7 c0 80 00 03 10    	mov    \$0x10030080,%eax
-[ 	]*[a-f0-9]+:	81 d0 80 00 03 10    	adc    \$0x10030080,%eax
-[ 	]*[a-f0-9]+:	81 c3 80 00 03 10    	add    \$0x10030080,%ebx
-[ 	]*[a-f0-9]+:	81 e1 80 00 03 10    	and    \$0x10030080,%ecx
-[ 	]*[a-f0-9]+:	81 fa 80 00 03 10    	cmp    \$0x10030080,%edx
-[ 	]*[a-f0-9]+:	81 cf 80 00 03 10    	or     \$0x10030080,%edi
-[ 	]*[a-f0-9]+:	81 de 80 00 03 10    	sbb    \$0x10030080,%esi
-[ 	]*[a-f0-9]+:	81 ed 80 00 03 10    	sub    \$0x10030080,%ebp
-[ 	]*[a-f0-9]+:	81 f4 80 00 03 10    	xor    \$0x10030080,%esp
-[ 	]*[a-f0-9]+:	f7 c1 80 00 03 10    	test   \$0x10030080,%ecx
-[ 	]*[a-f0-9]+:	c7 c0 81 00 03 10    	mov    \$0x10030081,%eax
-[ 	]*[a-f0-9]+:	81 d0 81 00 03 10    	adc    \$0x10030081,%eax
-[ 	]*[a-f0-9]+:	81 c3 81 00 03 10    	add    \$0x10030081,%ebx
-[ 	]*[a-f0-9]+:	81 e1 81 00 03 10    	and    \$0x10030081,%ecx
-[ 	]*[a-f0-9]+:	81 fa 81 00 03 10    	cmp    \$0x10030081,%edx
-[ 	]*[a-f0-9]+:	81 cf 81 00 03 10    	or     \$0x10030081,%edi
-[ 	]*[a-f0-9]+:	81 de 81 00 03 10    	sbb    \$0x10030081,%esi
-[ 	]*[a-f0-9]+:	81 ed 81 00 03 10    	sub    \$0x10030081,%ebp
-[ 	]*[a-f0-9]+:	81 f4 81 00 03 10    	xor    \$0x10030081,%esp
-[ 	]*[a-f0-9]+:	f7 c1 81 00 03 10    	test   \$0x10030081,%ecx
-[ 	]*[a-f0-9]+:	c7 c0 81 00 03 10    	mov    \$0x10030081,%eax
-[ 	]*[a-f0-9]+:	81 d0 81 00 03 10    	adc    \$0x10030081,%eax
-[ 	]*[a-f0-9]+:	81 c3 81 00 03 10    	add    \$0x10030081,%ebx
-[ 	]*[a-f0-9]+:	81 e1 81 00 03 10    	and    \$0x10030081,%ecx
-[ 	]*[a-f0-9]+:	81 fa 81 00 03 10    	cmp    \$0x10030081,%edx
-[ 	]*[a-f0-9]+:	81 cf 81 00 03 10    	or     \$0x10030081,%edi
-[ 	]*[a-f0-9]+:	81 de 81 00 03 10    	sbb    \$0x10030081,%esi
-[ 	]*[a-f0-9]+:	81 ed 81 00 03 10    	sub    \$0x10030081,%ebp
-[ 	]*[a-f0-9]+:	81 f4 81 00 03 10    	xor    \$0x10030081,%esp
-[ 	]*[a-f0-9]+:	f7 c1 81 00 03 10    	test   \$0x10030081,%ecx
+[ 	]*[a-f0-9]+:	c7 c0 74 00 03 10    	mov    \$0x10030074,%eax
+[ 	]*[a-f0-9]+:	81 d0 74 00 03 10    	adc    \$0x10030074,%eax
+[ 	]*[a-f0-9]+:	81 c3 74 00 03 10    	add    \$0x10030074,%ebx
+[ 	]*[a-f0-9]+:	81 e1 74 00 03 10    	and    \$0x10030074,%ecx
+[ 	]*[a-f0-9]+:	81 fa 74 00 03 10    	cmp    \$0x10030074,%edx
+[ 	]*[a-f0-9]+:	81 cf 74 00 03 10    	or     \$0x10030074,%edi
+[ 	]*[a-f0-9]+:	81 de 74 00 03 10    	sbb    \$0x10030074,%esi
+[ 	]*[a-f0-9]+:	81 ed 74 00 03 10    	sub    \$0x10030074,%ebp
+[ 	]*[a-f0-9]+:	81 f4 74 00 03 10    	xor    \$0x10030074,%esp
+[ 	]*[a-f0-9]+:	f7 c1 74 00 03 10    	test   \$0x10030074,%ecx
+[ 	]*[a-f0-9]+:	c7 c0 74 00 03 10    	mov    \$0x10030074,%eax
+[ 	]*[a-f0-9]+:	81 d0 74 00 03 10    	adc    \$0x10030074,%eax
+[ 	]*[a-f0-9]+:	81 c3 74 00 03 10    	add    \$0x10030074,%ebx
+[ 	]*[a-f0-9]+:	81 e1 74 00 03 10    	and    \$0x10030074,%ecx
+[ 	]*[a-f0-9]+:	81 fa 74 00 03 10    	cmp    \$0x10030074,%edx
+[ 	]*[a-f0-9]+:	81 cf 74 00 03 10    	or     \$0x10030074,%edi
+[ 	]*[a-f0-9]+:	81 de 74 00 03 10    	sbb    \$0x10030074,%esi
+[ 	]*[a-f0-9]+:	81 ed 74 00 03 10    	sub    \$0x10030074,%ebp
+[ 	]*[a-f0-9]+:	81 f4 74 00 03 10    	xor    \$0x10030074,%esp
+[ 	]*[a-f0-9]+:	f7 c1 74 00 03 10    	test   \$0x10030074,%ecx
+[ 	]*[a-f0-9]+:	c7 c0 75 00 03 10    	mov    \$0x10030075,%eax
+[ 	]*[a-f0-9]+:	81 d0 75 00 03 10    	adc    \$0x10030075,%eax
+[ 	]*[a-f0-9]+:	81 c3 75 00 03 10    	add    \$0x10030075,%ebx
+[ 	]*[a-f0-9]+:	81 e1 75 00 03 10    	and    \$0x10030075,%ecx
+[ 	]*[a-f0-9]+:	81 fa 75 00 03 10    	cmp    \$0x10030075,%edx
+[ 	]*[a-f0-9]+:	81 cf 75 00 03 10    	or     \$0x10030075,%edi
+[ 	]*[a-f0-9]+:	81 de 75 00 03 10    	sbb    \$0x10030075,%esi
+[ 	]*[a-f0-9]+:	81 ed 75 00 03 10    	sub    \$0x10030075,%ebp
+[ 	]*[a-f0-9]+:	81 f4 75 00 03 10    	xor    \$0x10030075,%esp
+[ 	]*[a-f0-9]+:	f7 c1 75 00 03 10    	test   \$0x10030075,%ecx
+[ 	]*[a-f0-9]+:	c7 c0 75 00 03 10    	mov    \$0x10030075,%eax
+[ 	]*[a-f0-9]+:	81 d0 75 00 03 10    	adc    \$0x10030075,%eax
+[ 	]*[a-f0-9]+:	81 c3 75 00 03 10    	add    \$0x10030075,%ebx
+[ 	]*[a-f0-9]+:	81 e1 75 00 03 10    	and    \$0x10030075,%ecx
+[ 	]*[a-f0-9]+:	81 fa 75 00 03 10    	cmp    \$0x10030075,%edx
+[ 	]*[a-f0-9]+:	81 cf 75 00 03 10    	or     \$0x10030075,%edi
+[ 	]*[a-f0-9]+:	81 de 75 00 03 10    	sbb    \$0x10030075,%esi
+[ 	]*[a-f0-9]+:	81 ed 75 00 03 10    	sub    \$0x10030075,%ebp
+[ 	]*[a-f0-9]+:	81 f4 75 00 03 10    	xor    \$0x10030075,%esp
+[ 	]*[a-f0-9]+:	f7 c1 75 00 03 10    	test   \$0x10030075,%ecx
 #pass
diff --git a/ld/testsuite/ld-i386/load1.d b/ld/testsuite/ld-i386/load1.d
index 9c4aa8e..2e4957b 100644
--- a/ld/testsuite/ld-i386/load1.d
+++ b/ld/testsuite/ld-i386/load1.d
@@ -7,52 +7,52 @@
 
 SYMBOL TABLE:
 #...
-0+8049170 l     O .data	0+1 bar
+0+8049164 l     O .data	0+1 bar
 #...
-0+8049171 g     O .data	0+1 foo
+0+8049165 g     O .data	0+1 foo
 #...
 
 Disassembly of section .text:
 
 0+8048074 <_start>:
-[ 	]*[a-f0-9]+:	c7 c0 70 91 04 08    	mov    \$0x8049170,%eax
-[ 	]*[a-f0-9]+:	81 d0 70 91 04 08    	adc    \$0x8049170,%eax
-[ 	]*[a-f0-9]+:	81 c3 70 91 04 08    	add    \$0x8049170,%ebx
-[ 	]*[a-f0-9]+:	81 e1 70 91 04 08    	and    \$0x8049170,%ecx
-[ 	]*[a-f0-9]+:	81 fa 70 91 04 08    	cmp    \$0x8049170,%edx
-[ 	]*[a-f0-9]+:	81 cf 70 91 04 08    	or     \$0x8049170,%edi
-[ 	]*[a-f0-9]+:	81 de 70 91 04 08    	sbb    \$0x8049170,%esi
-[ 	]*[a-f0-9]+:	81 ed 70 91 04 08    	sub    \$0x8049170,%ebp
-[ 	]*[a-f0-9]+:	81 f4 70 91 04 08    	xor    \$0x8049170,%esp
-[ 	]*[a-f0-9]+:	f7 c1 70 91 04 08    	test   \$0x8049170,%ecx
-[ 	]*[a-f0-9]+:	c7 c0 70 91 04 08    	mov    \$0x8049170,%eax
-[ 	]*[a-f0-9]+:	81 d0 70 91 04 08    	adc    \$0x8049170,%eax
-[ 	]*[a-f0-9]+:	81 c3 70 91 04 08    	add    \$0x8049170,%ebx
-[ 	]*[a-f0-9]+:	81 e1 70 91 04 08    	and    \$0x8049170,%ecx
-[ 	]*[a-f0-9]+:	81 fa 70 91 04 08    	cmp    \$0x8049170,%edx
-[ 	]*[a-f0-9]+:	81 cf 70 91 04 08    	or     \$0x8049170,%edi
-[ 	]*[a-f0-9]+:	81 de 70 91 04 08    	sbb    \$0x8049170,%esi
-[ 	]*[a-f0-9]+:	81 ed 70 91 04 08    	sub    \$0x8049170,%ebp
-[ 	]*[a-f0-9]+:	81 f4 70 91 04 08    	xor    \$0x8049170,%esp
-[ 	]*[a-f0-9]+:	f7 c1 70 91 04 08    	test   \$0x8049170,%ecx
-[ 	]*[a-f0-9]+:	c7 c0 71 91 04 08    	mov    \$0x8049171,%eax
-[ 	]*[a-f0-9]+:	81 d0 71 91 04 08    	adc    \$0x8049171,%eax
-[ 	]*[a-f0-9]+:	81 c3 71 91 04 08    	add    \$0x8049171,%ebx
-[ 	]*[a-f0-9]+:	81 e1 71 91 04 08    	and    \$0x8049171,%ecx
-[ 	]*[a-f0-9]+:	81 fa 71 91 04 08    	cmp    \$0x8049171,%edx
-[ 	]*[a-f0-9]+:	81 cf 71 91 04 08    	or     \$0x8049171,%edi
-[ 	]*[a-f0-9]+:	81 de 71 91 04 08    	sbb    \$0x8049171,%esi
-[ 	]*[a-f0-9]+:	81 ed 71 91 04 08    	sub    \$0x8049171,%ebp
-[ 	]*[a-f0-9]+:	81 f4 71 91 04 08    	xor    \$0x8049171,%esp
-[ 	]*[a-f0-9]+:	f7 c1 71 91 04 08    	test   \$0x8049171,%ecx
-[ 	]*[a-f0-9]+:	c7 c0 71 91 04 08    	mov    \$0x8049171,%eax
-[ 	]*[a-f0-9]+:	81 d0 71 91 04 08    	adc    \$0x8049171,%eax
-[ 	]*[a-f0-9]+:	81 c3 71 91 04 08    	add    \$0x8049171,%ebx
-[ 	]*[a-f0-9]+:	81 e1 71 91 04 08    	and    \$0x8049171,%ecx
-[ 	]*[a-f0-9]+:	81 fa 71 91 04 08    	cmp    \$0x8049171,%edx
-[ 	]*[a-f0-9]+:	81 cf 71 91 04 08    	or     \$0x8049171,%edi
-[ 	]*[a-f0-9]+:	81 de 71 91 04 08    	sbb    \$0x8049171,%esi
-[ 	]*[a-f0-9]+:	81 ed 71 91 04 08    	sub    \$0x8049171,%ebp
-[ 	]*[a-f0-9]+:	81 f4 71 91 04 08    	xor    \$0x8049171,%esp
-[ 	]*[a-f0-9]+:	f7 c1 71 91 04 08    	test   \$0x8049171,%ecx
+[ 	]*[a-f0-9]+:	c7 c0 64 91 04 08    	mov    \$0x8049164,%eax
+[ 	]*[a-f0-9]+:	81 d0 64 91 04 08    	adc    \$0x8049164,%eax
+[ 	]*[a-f0-9]+:	81 c3 64 91 04 08    	add    \$0x8049164,%ebx
+[ 	]*[a-f0-9]+:	81 e1 64 91 04 08    	and    \$0x8049164,%ecx
+[ 	]*[a-f0-9]+:	81 fa 64 91 04 08    	cmp    \$0x8049164,%edx
+[ 	]*[a-f0-9]+:	81 cf 64 91 04 08    	or     \$0x8049164,%edi
+[ 	]*[a-f0-9]+:	81 de 64 91 04 08    	sbb    \$0x8049164,%esi
+[ 	]*[a-f0-9]+:	81 ed 64 91 04 08    	sub    \$0x8049164,%ebp
+[ 	]*[a-f0-9]+:	81 f4 64 91 04 08    	xor    \$0x8049164,%esp
+[ 	]*[a-f0-9]+:	f7 c1 64 91 04 08    	test   \$0x8049164,%ecx
+[ 	]*[a-f0-9]+:	c7 c0 64 91 04 08    	mov    \$0x8049164,%eax
+[ 	]*[a-f0-9]+:	81 d0 64 91 04 08    	adc    \$0x8049164,%eax
+[ 	]*[a-f0-9]+:	81 c3 64 91 04 08    	add    \$0x8049164,%ebx
+[ 	]*[a-f0-9]+:	81 e1 64 91 04 08    	and    \$0x8049164,%ecx
+[ 	]*[a-f0-9]+:	81 fa 64 91 04 08    	cmp    \$0x8049164,%edx
+[ 	]*[a-f0-9]+:	81 cf 64 91 04 08    	or     \$0x8049164,%edi
+[ 	]*[a-f0-9]+:	81 de 64 91 04 08    	sbb    \$0x8049164,%esi
+[ 	]*[a-f0-9]+:	81 ed 64 91 04 08    	sub    \$0x8049164,%ebp
+[ 	]*[a-f0-9]+:	81 f4 64 91 04 08    	xor    \$0x8049164,%esp
+[ 	]*[a-f0-9]+:	f7 c1 64 91 04 08    	test   \$0x8049164,%ecx
+[ 	]*[a-f0-9]+:	c7 c0 65 91 04 08    	mov    \$0x8049165,%eax
+[ 	]*[a-f0-9]+:	81 d0 65 91 04 08    	adc    \$0x8049165,%eax
+[ 	]*[a-f0-9]+:	81 c3 65 91 04 08    	add    \$0x8049165,%ebx
+[ 	]*[a-f0-9]+:	81 e1 65 91 04 08    	and    \$0x8049165,%ecx
+[ 	]*[a-f0-9]+:	81 fa 65 91 04 08    	cmp    \$0x8049165,%edx
+[ 	]*[a-f0-9]+:	81 cf 65 91 04 08    	or     \$0x8049165,%edi
+[ 	]*[a-f0-9]+:	81 de 65 91 04 08    	sbb    \$0x8049165,%esi
+[ 	]*[a-f0-9]+:	81 ed 65 91 04 08    	sub    \$0x8049165,%ebp
+[ 	]*[a-f0-9]+:	81 f4 65 91 04 08    	xor    \$0x8049165,%esp
+[ 	]*[a-f0-9]+:	f7 c1 65 91 04 08    	test   \$0x8049165,%ecx
+[ 	]*[a-f0-9]+:	c7 c0 65 91 04 08    	mov    \$0x8049165,%eax
+[ 	]*[a-f0-9]+:	81 d0 65 91 04 08    	adc    \$0x8049165,%eax
+[ 	]*[a-f0-9]+:	81 c3 65 91 04 08    	add    \$0x8049165,%ebx
+[ 	]*[a-f0-9]+:	81 e1 65 91 04 08    	and    \$0x8049165,%ecx
+[ 	]*[a-f0-9]+:	81 fa 65 91 04 08    	cmp    \$0x8049165,%edx
+[ 	]*[a-f0-9]+:	81 cf 65 91 04 08    	or     \$0x8049165,%edi
+[ 	]*[a-f0-9]+:	81 de 65 91 04 08    	sbb    \$0x8049165,%esi
+[ 	]*[a-f0-9]+:	81 ed 65 91 04 08    	sub    \$0x8049165,%ebp
+[ 	]*[a-f0-9]+:	81 f4 65 91 04 08    	xor    \$0x8049165,%esp
+[ 	]*[a-f0-9]+:	f7 c1 65 91 04 08    	test   \$0x8049165,%ecx
 #pass
diff --git a/ld/testsuite/ld-i386/pr22782.d b/ld/testsuite/ld-i386/pr22782.d
new file mode 100644
index 0000000..29486ac
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr22782.d
@@ -0,0 +1,10 @@
+#as: --32
+#ld: -melf_i386
+#readelf: -SWs
+
+#failif
+#...
+[ 	]*\[.*\][ 	]+.*\.got\.plt .*
+#...
+.* _GLOBAL_OFFSET_TABLE_
+#...
diff --git a/ld/testsuite/ld-i386/pr22782.s b/ld/testsuite/ld-i386/pr22782.s
new file mode 100644
index 0000000..b8a42fc
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr22782.s
@@ -0,0 +1,15 @@
+	.text
+	.globl	_start
+	.type	_start, @function
+_start:
+	movl	errno@indntpoff, %eax
+	movl	%gs:(%eax), %eax
+	ret
+	.globl	errno
+	.hidden	errno
+	.section	.tbss,"awT",@nobits
+	.align 4
+	.type	errno, @object
+	.size	errno, 4
+errno:
+	.zero	4