Optimize R_386_GOT32/R_386_GOT32X only if addend is 0

Linker can't optimize R_386_GOT32 and R_386_GOT32X relocations if addend
isn't 0.  It isn't valid to convert

movl	foo@GOT+1(%ecx), %eax

to

leal	foo@GOTOFF+1(%ecx), %eax

nor to convert

movq	foo@GOTPCREL+1(%rip), %rax

to

leaq	foo(%rip), %rax

for x86-64.  We should check if addend is 0 before optimizing R_386_GOT32
and R_386_GOT32X relocations.  Testcases are added for i386 and x86-64.

bfd/

	* elf32-i386.c (elf_i386_convert_load): Skip if addend isn't 0.
	(elf_i386_relocate_section): Skip R_386_GOT32X optimization if
	addend isn't 0.

ld/testsuite/

	* ld-i386/i386.exp: Run mov2a, mov2b and mov3.
	* ld-i386/mov2.s: New file.
	* ld-i386/mov2a.d: Likewise.
	* ld-i386/mov2b.d: Likewise.
	* ld-i386/mov3.d: Likewise.
	* ld-i386/mov3.s: Likewise.
	* ld-x86-64/mov2.s: Likewise.
	* ld-x86-64/mov2a.d: Likewise.
	* ld-x86-64/mov2b.d: Likewise.
	* ld-x86-64/mov2c.d: Likewise.
	* ld-x86-64/mov2d.d: Likewise.
	* ld-x86-64/x86-64.exp: Run mov2a, mov2b, mov2c and mov2d.

13 files changed, 169 insertions, 0 deletions

diff --git a/ld/testsuite/ChangeLog b/ld/testsuite/ChangeLog
index d7ef3c4..f0ca105 100644
--- a/ld/testsuite/ChangeLog
+++ b/ld/testsuite/ChangeLog
@@ -1,3 +1,16 @@
+2015-12-04  H.J. Lu  <hongjiu.lu@intel.com>
+
+	* ld-i386/i386.exp: Run mov2a and mov2b.
+	* ld-i386/mov2.s: New file.
+	* ld-i386/mov2a.d: Likewise.
+	* ld-i386/mov2b.d: Likewise.
+	* ld-x86-64/mov2.s: Likewise.
+	* ld-x86-64/mov2a.d: Likewise.
+	* ld-x86-64/mov2b.d: Likewise.
+	* ld-x86-64/mov2c.d: Likewise.
+	* ld-x86-64/mov2d.d: Likewise.
+	* ld-x86-64/x86-64.exp: Run mov2a, mov2b, mov2c and mov2d.
+
 2015-12-01  H.J. Lu  <hongjiu.lu@intel.com>
 
 	PR ld/19319
diff --git a/ld/testsuite/ld-i386/i386.exp b/ld/testsuite/ld-i386/i386.exp
index a6601ed..fb1d3ea 100644
--- a/ld/testsuite/ld-i386/i386.exp
+++ b/ld/testsuite/ld-i386/i386.exp
@@ -293,6 +293,9 @@ run_dump_test "lea1e"
 run_dump_test "lea1f"
 run_dump_test "mov1a"
 run_dump_test "mov1b"
+run_dump_test "mov2a"
+run_dump_test "mov2b"
+run_dump_test "mov3"
 run_dump_test "branch1"
 run_dump_test "call1"
 run_dump_test "call2"
diff --git a/ld/testsuite/ld-i386/mov2.s b/ld/testsuite/ld-i386/mov2.s
new file mode 100644
index 0000000..3fa06ce
--- /dev/null
+++ b/ld/testsuite/ld-i386/mov2.s
@@ -0,0 +1,15 @@
+	.section	my_section,"aw",@progbits
+	.long	0x12345678
+	.text
+	.globl	foo
+	.type	foo, @function
+foo:
+	ret
+	.size	foo, .-foo
+	.globl	_start
+	.type	_start, @function
+_start:
+	movl	foo@GOT+1(%ecx), %eax
+	movl	__start_my_section@GOT+1(%ecx), %eax
+	movl	__stop_my_section@GOT+1(%ecx), %eax
+	.size	_start, .-_start
diff --git a/ld/testsuite/ld-i386/mov2a.d b/ld/testsuite/ld-i386/mov2a.d
new file mode 100644
index 0000000..d8756e5
--- /dev/null
+++ b/ld/testsuite/ld-i386/mov2a.d
@@ -0,0 +1,15 @@
+#source: mov2.s
+#as: --32
+#ld: -shared -melf_i386
+#objdump: -dw
+
+.*: +file format .*
+
+
+Disassembly of section .text:
+
+#...
+[ 	]*[a-f0-9]+:	8b 81 ([0-9a-f]{2} ){4} *	mov    -0x[a-f0-9]+\(%ecx\),%eax
+[ 	]*[a-f0-9]+:	8b 81 ([0-9a-f]{2} ){4} *	mov    -0x[a-f0-9]+\(%ecx\),%eax
+[ 	]*[a-f0-9]+:	8b 81 ([0-9a-f]{2} ){4} *	mov    -0x[a-f0-9]+\(%ecx\),%eax
+#pass
diff --git a/ld/testsuite/ld-i386/mov2b.d b/ld/testsuite/ld-i386/mov2b.d
new file mode 100644
index 0000000..ea5dd9b
--- /dev/null
+++ b/ld/testsuite/ld-i386/mov2b.d
@@ -0,0 +1,15 @@
+#source: mov2.s
+#as: --32
+#ld: -pie -melf_i386
+#objdump: -dw
+
+.*: +file format .*
+
+
+Disassembly of section .text:
+
+#...
+[ 	]*[a-f0-9]+:	8b 81 ([0-9a-f]{2} ){4} *	mov    -0x[a-f0-9]+\(%ecx\),%eax
+[ 	]*[a-f0-9]+:	8b 81 ([0-9a-f]{2} ){4} *	mov    -0x[a-f0-9]+\(%ecx\),%eax
+[ 	]*[a-f0-9]+:	8b 81 ([0-9a-f]{2} ){4} *	mov    -0x[a-f0-9]+\(%ecx\),%eax
+#pass
diff --git a/ld/testsuite/ld-i386/mov3.d b/ld/testsuite/ld-i386/mov3.d
new file mode 100644
index 0000000..17da244
--- /dev/null
+++ b/ld/testsuite/ld-i386/mov3.d
@@ -0,0 +1,14 @@
+#as: --32
+#ld: -melf_i386
+#objdump: -dw
+
+.*: +file format .*
+
+
+Disassembly of section .text:
+
+#...
+[ 	]*[a-f0-9]+:	8b 05 ([0-9a-f]{2} ){4} *	mov    0x[a-f0-9]+\,%eax
+[ 	]*[a-f0-9]+:	8b 05 ([0-9a-f]{2} ){4} *	mov    0x[a-f0-9]+\,%eax
+[ 	]*[a-f0-9]+:	8b 05 ([0-9a-f]{2} ){4} *	mov    0x[a-f0-9]+\,%eax
+#pass
diff --git a/ld/testsuite/ld-i386/mov3.s b/ld/testsuite/ld-i386/mov3.s
new file mode 100644
index 0000000..0dc54eb
--- /dev/null
+++ b/ld/testsuite/ld-i386/mov3.s
@@ -0,0 +1,15 @@
+	.section	my_section,"aw",@progbits
+	.long	0x12345678
+	.text
+	.globl	foo
+	.type	foo, @function
+foo:
+	ret
+	.size	foo, .-foo
+	.globl	_start
+	.type	_start, @function
+_start:
+	movl	foo@GOT+1, %eax
+	movl	__start_my_section@GOT+1, %eax
+	movl	__stop_my_section@GOT+1, %eax
+	.size	_start, .-_start
diff --git a/ld/testsuite/ld-x86-64/mov2.s b/ld/testsuite/ld-x86-64/mov2.s
new file mode 100644
index 0000000..95e474f
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/mov2.s
@@ -0,0 +1,15 @@
+	.section	my_section,"aw",@progbits
+	.long	0x12345678
+	.text
+	.globl	foo
+	.type	foo, @function
+foo:
+	ret
+	.size	foo, .-foo
+	.globl	_start
+	.type	_start, @function
+_start:
+	movq	foo@GOTPCREL+1(%rip), %rax
+	movq	__start_my_section@GOTPCREL+1(%rip), %rax
+	movq	__stop_my_section@GOTPCREL+1(%rip), %rax
+	.size	_start, .-_start
diff --git a/ld/testsuite/ld-x86-64/mov2a.d b/ld/testsuite/ld-x86-64/mov2a.d
new file mode 100644
index 0000000..aaf5707
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/mov2a.d
@@ -0,0 +1,15 @@
+#source: mov2.s
+#as: --64
+#ld: -shared -melf_x86_64
+#objdump: -dw
+
+.*: +file format .*
+
+
+Disassembly of section .text:
+
+#...
+[ 	]*[a-f0-9]+:	48 8b 05 ([0-9a-f]{2} ){4} *	mov    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+>
+[ 	]*[a-f0-9]+:	48 8b 05 ([0-9a-f]{2} ){4} *	mov    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+>
+[ 	]*[a-f0-9]+:	48 8b 05 ([0-9a-f]{2} ){4} *	mov    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+>
+#pass
diff --git a/ld/testsuite/ld-x86-64/mov2b.d b/ld/testsuite/ld-x86-64/mov2b.d
new file mode 100644
index 0000000..ee1b308
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/mov2b.d
@@ -0,0 +1,15 @@
+#source: mov2.s
+#as: --64
+#ld: -pie -melf_x86_64
+#objdump: -dw
+
+.*: +file format .*
+
+
+Disassembly of section .text:
+
+#...
+[ 	]*[a-f0-9]+:	48 8b 05 ([0-9a-f]{2} ){4} *	mov    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+>
+[ 	]*[a-f0-9]+:	48 8b 05 ([0-9a-f]{2} ){4} *	mov    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+>
+[ 	]*[a-f0-9]+:	48 8b 05 ([0-9a-f]{2} ){4} *	mov    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+>
+#pass
diff --git a/ld/testsuite/ld-x86-64/mov2c.d b/ld/testsuite/ld-x86-64/mov2c.d
new file mode 100644
index 0000000..8991121
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/mov2c.d
@@ -0,0 +1,15 @@
+#source: mov2.s
+#as: --x32
+#ld: -shared -melf32_x86_64
+#objdump: -dw
+
+.*: +file format .*
+
+
+Disassembly of section .text:
+
+#...
+[ 	]*[a-f0-9]+:	48 8b 05 ([0-9a-f]{2} ){4} *	mov    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+>
+[ 	]*[a-f0-9]+:	48 8b 05 ([0-9a-f]{2} ){4} *	mov    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+>
+[ 	]*[a-f0-9]+:	48 8b 05 ([0-9a-f]{2} ){4} *	mov    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+>
+#pass
diff --git a/ld/testsuite/ld-x86-64/mov2d.d b/ld/testsuite/ld-x86-64/mov2d.d
new file mode 100644
index 0000000..744028e
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/mov2d.d
@@ -0,0 +1,15 @@
+#source: mov2.s
+#as: --x32
+#ld: -pie -melf32_x86_64
+#objdump: -dw
+
+.*: +file format .*
+
+
+Disassembly of section .text:
+
+#...
+[ 	]*[a-f0-9]+:	48 8b 05 ([0-9a-f]{2} ){4} *	mov    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+>
+[ 	]*[a-f0-9]+:	48 8b 05 ([0-9a-f]{2} ){4} *	mov    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+>
+[ 	]*[a-f0-9]+:	48 8b 05 ([0-9a-f]{2} ){4} *	mov    0x[a-f0-9]+\(%rip\),%rax        # [a-f0-9]+ <_DYNAMIC\+0x[a-f0-9]+>
+#pass
diff --git a/ld/testsuite/ld-x86-64/x86-64.exp b/ld/testsuite/ld-x86-64/x86-64.exp
index f0f47eb..45b7f09 100644
--- a/ld/testsuite/ld-x86-64/x86-64.exp
+++ b/ld/testsuite/ld-x86-64/x86-64.exp
@@ -321,6 +321,10 @@ run_dump_test "mov1a"
 run_dump_test "mov1b"
 run_dump_test "mov1c"
 run_dump_test "mov1d"
+run_dump_test "mov2a"
+run_dump_test "mov2b"
+run_dump_test "mov2c"
+run_dump_test "mov2d"
 run_dump_test "load1a"
 run_dump_test "load1b"
 run_dump_test "load1c"