Correct eh_frame info for __glink_PLTresolve

My PPC64_OPT_LOCALENTRY patch of June 1, git commit f378ab099d, and
the later gold change, git commit 7ee7ff7015, added an insn in
__glink_PLTresolve which needs a corresponding adjustment in the
eh_frame info for asynchronous exceptions to unwind correctly.

It would have been OK for both ABIs to use +5 for the advance before
restore of LR, since we can put the DW_CFA_restore_extended on any
insn after the actual restore and before the r12/r0 copy is clobbered,
but it's slightly better to delay as much as possible.  There are
then more addresses where fewer CFA program insns are executed.

bfd/
	* elf64-ppc.c (ppc64_elf_size_stubs): Correct advance to
	restore of LR.
gold/
	* powerpc.cc (glink_eh_frame_fde_64v2): Correct advance to
	restore of LR.
	(glink_eh_frame_fde_64v1): Advance to restore of LR at latest
	possible insn.

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 9f478f2..66d8124 100644 (file)
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,8 @@
+2017-07-23  Alan Modra  <amodra@gmail.com>
+
+       * elf64-ppc.c (ppc64_elf_size_stubs): Correct advance to
+       restore of LR.
+
 2017-07-19  Szabolcs Nagy  <szabolcs.nagy@arm.com>
 
        PR ld/18841

diff --git a/bfd/elf64-ppc.c b/bfd/elf64-ppc.c
index 9903373..f399e35 100644 (file)
--- a/bfd/elf64-ppc.c
+++ b/bfd/elf64-ppc.c
@@ -12871,7 +12871,7 @@ ppc64_elf_size_stubs (struct bfd_link_info *info)
          *p++ = DW_CFA_register;
          *p++ = 65;
          *p++ = htab->opd_abi ? 12 : 0;
-         *p++ = DW_CFA_advance_loc + 4;
+         *p++ = DW_CFA_advance_loc + (htab->opd_abi ? 5 : 7);
          *p++ = DW_CFA_restore_extended;
          *p++ = 65;
          p += ((24 + align - 1) & -align) - 24;

diff --git a/gold/ChangeLog b/gold/ChangeLog
index 0dc3972..01f0d34 100644 (file)
--- a/gold/ChangeLog
+++ b/gold/ChangeLog
@@ -1,3 +1,10 @@
+2017-07-23  Alan Modra  <amodra@gmail.com>
+
+       * powerpc.cc (glink_eh_frame_fde_64v2): Correct advance to
+       restore of LR.
+       (glink_eh_frame_fde_64v1): Advance to restore of LR at latest
+       possible insn.
+
 2017-07-18  Nick Clifton  <nickc@redhat.com>
 
        PR 21775

diff --git a/gold/powerpc.cc b/gold/powerpc.cc
index fcbf177..a4966b8 100644 (file)
--- a/gold/powerpc.cc
+++ b/gold/powerpc.cc
@@ -3987,7 +3987,7 @@ static const unsigned char glink_eh_frame_fde_64v1[] =
   0,                                   // Augmentation size.
   elfcpp::DW_CFA_advance_loc + 1,
   elfcpp::DW_CFA_register, 65, 12,
-  elfcpp::DW_CFA_advance_loc + 4,
+  elfcpp::DW_CFA_advance_loc + 5,
   elfcpp::DW_CFA_restore_extended, 65
 };
 
@@ -3999,7 +3999,7 @@ static const unsigned char glink_eh_frame_fde_64v2[] =
   0,                                   // Augmentation size.
   elfcpp::DW_CFA_advance_loc + 1,
   elfcpp::DW_CFA_register, 65, 0,
-  elfcpp::DW_CFA_advance_loc + 4,
+  elfcpp::DW_CFA_advance_loc + 7,
   elfcpp::DW_CFA_restore_extended, 65
 };