ppc476 linker workaround shared lib fixes

When building a shared lib from non-PIC objects, we'll get dynamic
text relocations.  These need to move with any insns we move.
Otherwise the dynamic reloc will modify the branch, resulting in
crashes and other unpleasant behaviour.

Also, ld -r --ppc476-workaround used with sufficiently aligned PIC
objects needs a fix for emitted REL16 relocs.

bfd/
	* elf64-ppc.c (ppc_elf_relocate_section): Move dynamic text
	relocs with insns moved by --ppc476-workaround.  Correct
	output of REL16 relocs.
ld/testsuite/
	* ld-powerpc/ppc476-shared.s,
	* ld-powerpc/ppc476-shared.lnk,
	* ld-powerpc/ppc476-shared.d,
	* ld-powerpc/ppc476-shared2.d: New tests.
	* ld-powerpc/powerpc.exp: Run them.

6 files changed, 72 insertions, 0 deletions

diff --git a/ld/testsuite/ChangeLog b/ld/testsuite/ChangeLog
index fe62990..e51f16b 100644
--- a/ld/testsuite/ChangeLog
+++ b/ld/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2015-06-05  Alan Modra  <amodra@gmail.com>
+
+	* ld-powerpc/ppc476-shared.s,
+	* ld-powerpc/ppc476-shared.lnk,
+	* ld-powerpc/ppc476-shared.d,
+	* ld-powerpc/ppc476-shared2.d: New tests.
+	* ld-powerpc/powerpc.exp: Run them.
+
 2015-06-02  Jiong Wang  <jiong.wang@arm.com>
 
 	* ld-aarch64/emit-relocs-313.s: Use gotpage_lo15.
diff --git a/ld/testsuite/ld-powerpc/powerpc.exp b/ld/testsuite/ld-powerpc/powerpc.exp
index 48aec4a..976e89b 100644
--- a/ld/testsuite/ld-powerpc/powerpc.exp
+++ b/ld/testsuite/ld-powerpc/powerpc.exp
@@ -325,3 +325,6 @@ run_dump_test "attr-gnu-12-11"
 run_dump_test "attr-gnu-12-21"
 
 run_dump_test "vle-multiseg-6"
+
+run_dump_test "ppc476-shared"
+run_dump_test "ppc476-shared2"
diff --git a/ld/testsuite/ld-powerpc/ppc476-shared.d b/ld/testsuite/ld-powerpc/ppc476-shared.d
new file mode 100644
index 0000000..8fda847
--- /dev/null
+++ b/ld/testsuite/ld-powerpc/ppc476-shared.d
@@ -0,0 +1,30 @@
+#source: ppc476-shared.s
+#as: -a32
+#ld: -melf32ppc -q -shared --ppc476-workaround -T ppc476-shared.lnk
+#objdump: -dr
+#target: powerpc*-*-*
+
+.*:     file format .*
+
+Disassembly of section \.text:
+
+0+fffc <\.text>:
+    fffc:	(48 01 00 04|04 00 01 48) 	b       20000 .*
+   10000:	(38 63 00 00|00 00 63 38) 	addi    r3,r3,0
+			1000[02]: R_PPC_ADDR16_LO	.bss
+	\.\.\.
+   1fff0:	(42 9f 00 05|05 00 9f 42) 	bcl     .*
+   1fff4:	(7d 28 02 a6|a6 02 28 7d) 	mflr    r9
+   1fff8:	(3d 29 00 00|00 00 29 3d) 	addis   r9,r9,0
+			1fff[8a]: R_PPC_REL16_HA	.bss\+0x[46]
+   1fffc:	(48 00 00 14|14 00 00 48) 	b       20010 .*
+   20000:	(3c 60 00 00|00 00 60 3c) 	lis     r3,0
+			2000[02]: R_PPC_ADDR16_HA	.bss
+   20004:	(4b fe ff fc|fc ff fe 4b) 	b       10000 .*
+   20008:	(48 00 00 02|02 00 00 48) 	ba      0 .*
+   2000c:	(48 00 00 02|02 00 00 48) 	ba      0 .*
+   20010:	(39 29 01 00|00 01 29 39) 	addi    r9,r9,256
+			2001[02]: R_PPC_REL16_LO	.bss\+0x1[ce]
+   20014:	(4b ff ff ec|ec ff ff 4b) 	b       20000 .*
+   20018:	(48 00 00 02|02 00 00 48) 	ba      0 .*
+   2001c:	(48 00 00 02|02 00 00 48) 	ba      0 .*
diff --git a/ld/testsuite/ld-powerpc/ppc476-shared.lnk b/ld/testsuite/ld-powerpc/ppc476-shared.lnk
new file mode 100644
index 0000000..5339358
--- /dev/null
+++ b/ld/testsuite/ld-powerpc/ppc476-shared.lnk
@@ -0,0 +1,6 @@
+SECTIONS
+{
+  . = 0xfffc;
+  .text : { *(.text) }
+  .bss : { *(.bss) }
+}
diff --git a/ld/testsuite/ld-powerpc/ppc476-shared.s b/ld/testsuite/ld-powerpc/ppc476-shared.s
new file mode 100644
index 0000000..6774bad
--- /dev/null
+++ b/ld/testsuite/ld-powerpc/ppc476-shared.s
@@ -0,0 +1,13 @@
+ .text
+ lis 3,x@ha
+ addi 3,3,x@l
+
+ .org 0xfff4
+ bcl 20,31,.+4
+0:
+ mflr 9
+ addis 9,9,x-0b@ha
+ addi 9,9,x-0b@l
+
+ .section .bss,"aw",@nobits
+x: .space 4
diff --git a/ld/testsuite/ld-powerpc/ppc476-shared2.d b/ld/testsuite/ld-powerpc/ppc476-shared2.d
new file mode 100644
index 0000000..ebb8bf1
--- /dev/null
+++ b/ld/testsuite/ld-powerpc/ppc476-shared2.d
@@ -0,0 +1,12 @@
+#source: ppc476-shared.s
+#as: -a32
+#ld: -melf32ppc -shared --ppc476-workaround -T ppc476-shared.lnk
+#objdump: -R
+#target: powerpc*-*-*
+
+.*:     file format .*
+
+DYNAMIC RELOCATION RECORDS
+OFFSET   TYPE              VALUE 
+0001000[02] R_PPC_ADDR16_LO   \.text\+0x000200f4
+0002000[02] R_PPC_ADDR16_HA   \.text\+0x000200f4