[AArch64] BFD_RELOC_AARCH64_TLSLE_ADD_LO12 should enable overflow check

BFD_RELOC_AARCH64_TLSLE_ADD_LO12 is used to generate simplest
one-instruction addressing for TLS LE model when tls size is smaller
4K. Linker need to make sure there is no TLS offset overflow.

2015-06-01  Jiong Wang  <jiong.wang@arm.com>

bfd/
  * elfnn-aarch64.c (elfNN_aarch64_howto_table): Set overflow type to
  complain_overflow_unsigned for BFD_RELOC_AARCH64_TLSLE_ADD_LO12.
  * elfxx-aarch64.c (_bfd_aarch64_elf_resolve_relocation): Don't use
  PGOFF for BFD_RELOC_AARCH64_TLSLE_ADD_LO12, that will mask off all
  potential high overflowed bits.

ld/testsuite/
  * ld-aarch64/tprel_add_lo12_overflow.s: New testcase.
  * ld-aarch64/tprel_add_lo12_overflow.d: Nex expectation file.
  * ld-aarch64/aarch64-elf.exp: Run new testcase.

bfd/ChangeLog

@@ -1,3 +1,10 @@
+2015-06-01  Jiong Wang  <jiong.wang@arm.com>
+
+	* elfnn-aarch64.c (elfNN_aarch64_howto_table): Set overflow type to
+	complain_overflow_unsigned for BFD_RELOC_AARCH64_TLSLE_ADD_LO12.
+	* elfxx-aarch64.c (_bfd_aarch64_elf_resolve_relocation): Don't use
+	PGOFF for BFD_RELOC_AARCH64_TLSLE_ADD_LO12.
+
 2015-06-01  Jiong Wang  <jiong.wang@arm.com>
 
 	* elfnn-aarch64.c (aarch64_reloc_got_type): Support

bfd/elfnn-aarch64.c

@@ -1083,7 +1083,7 @@ static reloc_howto_type elfNN_aarch64_howto_table[] =
 	 12,			/* bitsize */
 	 FALSE,			/* pc_relative */
 	 0,			/* bitpos */
-	 complain_overflow_dont,	/* complain_on_overflow */
+	 complain_overflow_unsigned,	/* complain_on_overflow */
 	 bfd_elf_generic_reloc,	/* special_function */
 	 AARCH64_R_STR (TLSLE_ADD_TPREL_LO12),	/* name */
 	 FALSE,			/* partial_inplace */

bfd/elfxx-aarch64.c

@@ -435,11 +435,14 @@ _bfd_aarch64_elf_resolve_relocation (bfd_reloc_code_real_type r_type,
     case BFD_RELOC_AARCH64_TLSGD_ADD_LO12_NC:
     case BFD_RELOC_AARCH64_TLSIE_LD32_GOTTPREL_LO12_NC:
     case BFD_RELOC_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
-    case BFD_RELOC_AARCH64_TLSLE_ADD_TPREL_LO12:
     case BFD_RELOC_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
       value = PG_OFFSET (value + addend);
       break;
 
+    case BFD_RELOC_AARCH64_TLSLE_ADD_TPREL_LO12:
+      value = value + addend;
+      break;
+
     case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G1:
     case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
       value = (value + addend) & (bfd_vma) 0xffff0000;

ld/testsuite/ChangeLog

@@ -1,3 +1,9 @@
+2015-06-01  Jiong Wang  <jiong.wang@arm.com>
+
+	* ld-aarch64/tprel_add_lo12_overflow.s: New testcase.
+	* ld-aarch64/tprel_add_lo12_overflow.d: Nex expectation file.
+	* ld-aarch64/aarch64-elf.exp: Run new testcase.
+
 2015-06-01  Jiong Wang  <jiong.wang@arm.com>
 
 	* ld-aarch64/emit-relocs-313.s: New test file.

ld/testsuite/ld-aarch64/aarch64-elf.exp

@@ -146,6 +146,7 @@ run_dump_test "gc-relocs-257-dyn"
 run_dump_test "gc-relocs-257"
 run_dump_test "pr17415"
 run_dump_test "tprel_g2_overflow"
+run_dump_test "tprel_add_lo12_overflow"
 
 # ifunc tests
 run_dump_test "ifunc-1"

ld/testsuite/ld-aarch64/tprel_add_lo12_overflow.d

@@ -0,0 +1,6 @@
+#name: TLS offset out of range - TPREL_ADD_LO12
+#source: tprel_add_lo12_overflow.s
+#as:
+#ld: -e0
+#error: .*\(.text\+0x\d+\): relocation truncated to fit: R_AARCH64_TLSLE_ADD_TPREL_LO12 against symbol `i' .*
+

ld/testsuite/ld-aarch64/tprel_add_lo12_overflow.s

@@ -0,0 +1,23 @@
+	.cpu generic
+	.global	ff
+	.section        .tdata,"awT",%progbits
+	.align	2
+	.type	ff, %object
+         # Maximum 12bit - 16byte TCB header is the upper limit
+	 # for tprel_add_lo12
+	.size	ff, 4096 - 16
+ff:
+	.zero	4096 - 16
+	.global	i
+	.type	i, %object
+	.size	i, 4
+i:
+	.zero	4
+	.text
+	.align	2
+	.global	main
+	.type	main, %function
+main:
+	add	x0, x0, #:tprel_lo12:i
+	ret
+	.size	main, .-main