PR ld/22570: MIPS/BFD: Fix TLS relocation resolution for PIE executables

Correct a commit 0e1862bb401f ("Add output_type to bfd_link_info") issue
and use `bfd_link_dll' rather than `bfd_link_pic' in determining whether
to fully resolve GD, LD and IE TLS relocations referring to symbols
locally defined rather than deferring them to the load time by means of
dynamic relocations.

Such symbols cannot be preempted in PIE executables, which are
necessarily PIC, and therefore their values (thread pointer offsets) are
fixed at the static link time as is the associated module ID of the main
executable.

Given the `tlsbin-o32.s' and `tlsdyn-o32.s' sources from our test suite
this removes the absolute TLS relocations from the static:

DYNAMIC RELOCATION RECORDS
OFFSET   TYPE              VALUE
00000000 R_MIPS_NONE       *ABS*
1000002c R_MIPS_TLS_TPREL32  *ABS*
10000030 R_MIPS_TLS_DTPMOD32  *ABS*
10000038 R_MIPS_TLS_DTPMOD32  *ABS*

and the dynamic:

DYNAMIC RELOCATION RECORDS
OFFSET   TYPE              VALUE
00000000 R_MIPS_NONE       *ABS*
1000002c R_MIPS_TLS_TPREL32  *ABS*
10000038 R_MIPS_TLS_DTPMOD32  *ABS*
10000044 R_MIPS_TLS_DTPMOD32  *ABS*
10000030 R_MIPS_TLS_DTPMOD32  tlsvar_gd
10000034 R_MIPS_TLS_DTPREL32  tlsvar_gd
10000040 R_MIPS_TLS_TPREL32  tlsvar_ie

PIE executable respectively, as reported by `objdump -R', and fills the
corresponding GOT slots with the values expected, as recorded with the
test cases added.  The new output from `objdump -R' is:

DYNAMIC RELOCATION RECORDS (none)

and:

DYNAMIC RELOCATION RECORDS
OFFSET   TYPE              VALUE
00000000 R_MIPS_NONE       *ABS*
10000030 R_MIPS_TLS_DTPMOD32  tlsvar_gd
10000034 R_MIPS_TLS_DTPREL32  tlsvar_gd
10000040 R_MIPS_TLS_TPREL32  tlsvar_ie

for the static and the dynamic executable respectively.

2018-07-11  Maciej W. Rozycki  <macro@mips.com>
            Rich Felker  <bugdal@aerifal.cx>

	bfd/
	PR ld/22570
	* elfxx-mips.c (mips_tls_got_relocs): Use `bfd_link_dll' rather
	than `bfd_link_pic' to determine whether dynamic relocations are
	to be produced.
	(mips_elf_initialize_tls_slots): Likewise.

	ld/
	PR ld/22570
	* testsuite/ld-mips-elf/tlsbin-pie-o32.d: New test.
	* testsuite/ld-mips-elf/tlsbin-pie-o32.got: New test.
	* testsuite/ld-mips-elf/tlsdyn-pie-o32.d: New test.
	* testsuite/ld-mips-elf/tlsdyn-pie-o32.got: New test.
	* testsuite/ld-mips-elf/mips-elf.exp: Run the new tests.

8 files changed, 150 insertions, 4 deletions

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index dd6ecd9..402cdc4 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,12 @@
+2018-07-11  Maciej W. Rozycki  <macro@mips.com>
+	    Rich Felker  <bugdal@aerifal.cx>
+
+	PR ld/22570
+	* elfxx-mips.c (mips_tls_got_relocs): Use `bfd_link_dll' rather
+	than `bfd_link_pic' to determine whether dynamic relocations are
+	to be produced.
+	(mips_elf_initialize_tls_slots): Likewise.
+
 2018-07-10  Maciej W. Rozycki  <macro@mips.com>
 
 	* elflink.c (bfd_elf_final_link): Rename `remove' local variable
diff --git a/bfd/elfxx-mips.c b/bfd/elfxx-mips.c
index 990e3a1..a353907 100644
--- a/bfd/elfxx-mips.c
+++ b/bfd/elfxx-mips.c
@@ -3255,7 +3255,7 @@ mips_tls_got_relocs (struct bfd_link_info *info, unsigned char tls_type,
       && (!bfd_link_pic (info) || !SYMBOL_REFERENCES_LOCAL (info, h)))
     indx = h->dynindx;
 
-  if ((bfd_link_pic (info) || indx != 0)
+  if ((bfd_link_dll (info) || indx != 0)
       && (h == NULL
 	  || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
 	  || h->root.type != bfd_link_hash_undefweak))
@@ -3273,7 +3273,7 @@ mips_tls_got_relocs (struct bfd_link_info *info, unsigned char tls_type,
       return 1;
 
     case GOT_TLS_LDM:
-      return bfd_link_pic (info) ? 1 : 0;
+      return bfd_link_dll (info) ? 1 : 0;
 
     default:
       return 0;
@@ -3367,7 +3367,7 @@ mips_elf_initialize_tls_slots (bfd *abfd, struct bfd_link_info *info,
   if (entry->tls_initialized)
     return;
 
-  if ((bfd_link_pic (info) || indx != 0)
+  if ((bfd_link_dll (info) || indx != 0)
       && (h == NULL
 	  || ELF_ST_VISIBILITY (h->root.other) == STV_DEFAULT
 	  || h->root.type != bfd_link_hash_undefweak))
@@ -3442,7 +3442,7 @@ mips_elf_initialize_tls_slots (bfd *abfd, struct bfd_link_info *info,
 			 sgot->contents + got_offset
 			 + MIPS_ELF_GOT_SIZE (abfd));
 
-      if (!bfd_link_pic (info))
+      if (!bfd_link_dll (info))
 	MIPS_ELF_PUT_WORD (abfd, 1,
 			   sgot->contents + got_offset);
       else
diff --git a/ld/ChangeLog b/ld/ChangeLog
index f2c1103..ea5468f 100644
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,3 +1,12 @@
+2018-07-11  Maciej W. Rozycki  <macro@mips.com>
+
+	PR ld/22570
+	* testsuite/ld-mips-elf/tlsbin-pie-o32.d: New test.
+	* testsuite/ld-mips-elf/tlsbin-pie-o32.got: New test.
+	* testsuite/ld-mips-elf/tlsdyn-pie-o32.d: New test.
+	* testsuite/ld-mips-elf/tlsdyn-pie-o32.got: New test.
+	* testsuite/ld-mips-elf/mips-elf.exp: Run the new tests.
+
 2018-07-11  Alan Modra  <amodra@gmail.com>
 
 	* testsuite/ld-elf/hash.d: Comment on mips xfail.
diff --git a/ld/testsuite/ld-mips-elf/mips-elf.exp b/ld/testsuite/ld-mips-elf/mips-elf.exp
index 6aae2f9..ba3f161 100644
--- a/ld/testsuite/ld-mips-elf/mips-elf.exp
+++ b/ld/testsuite/ld-mips-elf/mips-elf.exp
@@ -863,6 +863,12 @@ set mips_tls_tests {
      "-EB -march=mips1 -32 -KPIC" {tlsbin-o32.s}
      {{objdump {-dr -m mips:isa32r2} tlsbin-o32.d} {objdump -srj.got tlsbin-o32.got}}
      "tls-static-o32"}
+    {"Static PIE executable with TLS"
+     "-static -pie -melf32btsmip -T mips-dyn.ld" ""
+     "-EB -march=mips1 -32 -KPIC" {tlsbin-o32.s}
+     {{objdump {-dr -m mips:isa32r2} tlsbin-pie-o32.d}
+      {objdump -Rsj.got tlsbin-pie-o32.got}}
+     "tls-static-pie-o32"}
     {"Shared library with TLS" "-shared -melf32btsmip -T mips-lib.ld" ""
      "-EB -march=mips1 -32 -KPIC" {tlslib-o32.s}
      {{objdump {-dr -m mips:isa32r2} tlslib-o32.d} {objdump -Rsj.got tlslib-o32.got}}
@@ -872,6 +878,12 @@ set mips_tls_tests {
      "-EB -march=mips1 -32 -KPIC" {tlsdyn-o32.s}
      {{objdump {-dr -m mips:isa32r2} tlsdyn-o32.d} {objdump -Rsj.got tlsdyn-o32.got}}
      "tls-dynamic-o32"}
+    {"Dynamic PIE executable with TLS"
+     "-pie -melf32btsmip -T mips-dyn.ld tmpdir/tlslib-o32.so" ""
+     "-EB -march=mips1 -32 -KPIC" {tlsdyn-o32.s}
+     {{objdump {-dr -m mips:isa32r2} tlsdyn-pie-o32.d}
+      {objdump -Rsj.got tlsdyn-pie-o32.got}}
+     "tls-dynamic-pie-o32"}
     {"Shared library with multiple GOTs and TLS"
      "-shared -melf32btsmip -T mips-lib.ld" ""
      "-EB -march=mips1 -32 -KPIC" {tls-multi-got-1-1.s tls-multi-got-1-2.s}
diff --git a/ld/testsuite/ld-mips-elf/tlsbin-pie-o32.d b/ld/testsuite/ld-mips-elf/tlsbin-pie-o32.d
new file mode 100644
index 0000000..1d6536d
--- /dev/null
+++ b/ld/testsuite/ld-mips-elf/tlsbin-pie-o32.d
@@ -0,0 +1,43 @@
+.*:     file format elf32-tradbigmips
+
+Disassembly of section \.text:
+
+.* <__start>:
+  .*:	3c1c0fc0 	lui	gp,0xfc0
+  .*:	279c7d20 	addiu	gp,gp,32032
+  .*:	0399e021 	addu	gp,gp,t9
+  .*:	27bdfff0 	addiu	sp,sp,-16
+  .*:	afbe0008 	sw	s8,8\(sp\)
+  .*:	03a0f025 	move	s8,sp
+  .*:	afbc0000 	sw	gp,0\(sp\)
+  .*:	8f998018 	lw	t9,-32744\(gp\)
+  .*:	27848020 	addiu	a0,gp,-32736
+  .*:	0320f809 	jalr	t9
+  .*:	00000000 	nop
+  .*:	8fdc0000 	lw	gp,0\(s8\)
+  .*:	00000000 	nop
+  .*:	8f998018 	lw	t9,-32744\(gp\)
+  .*:	27848028 	addiu	a0,gp,-32728
+  .*:	0320f809 	jalr	t9
+  .*:	00000000 	nop
+  .*:	8fdc0000 	lw	gp,0\(s8\)
+  .*:	00401025 	move	v0,v0
+  .*:	3c030000 	lui	v1,0x0
+  .*:	24638000 	addiu	v1,v1,-32768
+  .*:	00621821 	addu	v1,v1,v0
+  .*:	7c02283b 	rdhwr	v0,\$5
+  .*:	8f83801c 	lw	v1,-32740\(gp\)
+  .*:	00000000 	nop
+  .*:	00621821 	addu	v1,v1,v0
+  .*:	7c02283b 	rdhwr	v0,\$5
+  .*:	3c030000 	lui	v1,0x0
+  .*:	24639004 	addiu	v1,v1,-28668
+  .*:	00621821 	addu	v1,v1,v0
+  .*:	03c0e825 	move	sp,s8
+  .*:	8fbe0008 	lw	s8,8\(sp\)
+  .*:	03e00008 	jr	ra
+  .*:	27bd0010 	addiu	sp,sp,16
+
+.* <__tls_get_addr>:
+  .*:	03e00008 	jr	ra
+  .*:	00000000 	nop
diff --git a/ld/testsuite/ld-mips-elf/tlsbin-pie-o32.got b/ld/testsuite/ld-mips-elf/tlsbin-pie-o32.got
new file mode 100644
index 0000000..c5efbb7
--- /dev/null
+++ b/ld/testsuite/ld-mips-elf/tlsbin-pie-o32.got
@@ -0,0 +1,7 @@
+.*:     file format elf32-tradbigmips
+
+DYNAMIC RELOCATION RECORDS \(none\)
+
+Contents of section \.got:
+ 10000020 00000000 80000000 00400378 ffff900c  .*
+ 10000030 00000001 ffff8008 00000001 00000000  .*
diff --git a/ld/testsuite/ld-mips-elf/tlsdyn-pie-o32.d b/ld/testsuite/ld-mips-elf/tlsdyn-pie-o32.d
new file mode 100644
index 0000000..4df024f
--- /dev/null
+++ b/ld/testsuite/ld-mips-elf/tlsdyn-pie-o32.d
@@ -0,0 +1,53 @@
+.*:     file format elf32-tradbigmips
+
+Disassembly of section \.text:
+
+.* <__start>:
+  .*:	3c1c0fc0 	lui	gp,0xfc0
+  .*:	279c7bd0 	addiu	gp,gp,31696
+  .*:	0399e021 	addu	gp,gp,t9
+  .*:	27bdfff0 	addiu	sp,sp,-16
+  .*:	afbe0008 	sw	s8,8\(sp\)
+  .*:	03a0f025 	move	s8,sp
+  .*:	afbc0000 	sw	gp,0\(sp\)
+  .*:	8f998018 	lw	t9,-32744\(gp\)
+  .*:	27848034 	addiu	a0,gp,-32716
+  .*:	0320f809 	jalr	t9
+  .*:	00000000 	nop
+  .*:	8fdc0000 	lw	gp,0\(s8\)
+  .*:	00000000 	nop
+  .*:	8f998018 	lw	t9,-32744\(gp\)
+  .*:	27848020 	addiu	a0,gp,-32736
+  .*:	0320f809 	jalr	t9
+  .*:	00000000 	nop
+  .*:	8fdc0000 	lw	gp,0\(s8\)
+  .*:	00000000 	nop
+  .*:	8f998018 	lw	t9,-32744\(gp\)
+  .*:	27848028 	addiu	a0,gp,-32728
+  .*:	0320f809 	jalr	t9
+  .*:	00000000 	nop
+  .*:	8fdc0000 	lw	gp,0\(s8\)
+  .*:	00401025 	move	v0,v0
+  .*:	3c030000 	lui	v1,0x0
+  .*:	24638000 	addiu	v1,v1,-32768
+  .*:	00621821 	addu	v1,v1,v0
+  .*:	7c02283b 	rdhwr	v0,\$5
+  .*:	8f83801c 	lw	v1,-32740\(gp\)
+  .*:	00000000 	nop
+  .*:	00621821 	addu	v1,v1,v0
+  .*:	8f838030 	lw	v1,-32720\(gp\)
+  .*:	00000000 	nop
+  .*:	00621821 	addu	v1,v1,v0
+  .*:	7c02283b 	rdhwr	v0,\$5
+  .*:	3c030000 	lui	v1,0x0
+  .*:	24639004 	addiu	v1,v1,-28668
+  .*:	00621821 	addu	v1,v1,v0
+  .*:	03c0e825 	move	sp,s8
+  .*:	8fbe0008 	lw	s8,8\(sp\)
+  .*:	03e00008 	jr	ra
+  .*:	27bd0010 	addiu	sp,sp,16
+
+.* <__tls_get_addr>:
+  .*:	03e00008 	jr	ra
+  .*:	00000000 	nop
+	\.\.\.
diff --git a/ld/testsuite/ld-mips-elf/tlsdyn-pie-o32.got b/ld/testsuite/ld-mips-elf/tlsdyn-pie-o32.got
new file mode 100644
index 0000000..c5dd695
--- /dev/null
+++ b/ld/testsuite/ld-mips-elf/tlsdyn-pie-o32.got
@@ -0,0 +1,13 @@
+.*:     file format elf32-tradbigmips
+
+DYNAMIC RELOCATION RECORDS
+OFFSET   TYPE              VALUE 
+00000000 R_MIPS_NONE       \*ABS\*
+10000030 R_MIPS_TLS_DTPMOD32  tlsvar_gd
+10000034 R_MIPS_TLS_DTPREL32  tlsvar_gd
+10000040 R_MIPS_TLS_TPREL32  tlsvar_ie
+
+Contents of section .got:
+ 10000020 00000000 80000000 004004ec ffff900c  .*
+ 10000030 00000000 00000000 00000001 00000000  .*
+ 10000040 00000000 00000001 ffff8008           .*