powerpc: fix ifunc-sel.h with GCC 6

On 32-bit PowerPC GCC 6 always saves the PIC register on the stack in
the prologue and adjust the stack in the epilogue. It is therefore not
possible anymore to just exit the function in the inline asm code,
otherwise it corrupts the stack pointer. This causes the following tests
to fail when using GCC 6:

FAIL: elf/ifuncmain1
FAIL: elf/ifuncmain1pic
FAIL: elf/ifuncmain1picstatic
FAIL: elf/ifuncmain1pie
FAIL: elf/ifuncmain1staticpic
FAIL: elf/ifuncmain1staticpie
FAIL: elf/ifuncmain1vis
FAIL: elf/ifuncmain1vispic
FAIL: elf/ifuncmain1vispie
FAIL: elf/ifuncmain2pic
FAIL: elf/ifuncmain2picstatic
FAIL: elf/ifuncmain3
FAIL: elf/ifuncmain4picstatic
FAIL: elf/ifuncmain5
FAIL: elf/ifuncmain5picstatic
FAIL: elf/ifuncmain5staticpic

The solution is to replace the beqlr instructions by a beq to the end
of the inline asm code. This fixes all the above failures.

ChangeLog:
	* sysdeps/powerpc/ifunc-sel.h (ifunc_sel): Replace beqlr instructions
	by beq instructions jumping to the end of the function.

(cherry picked from commit ee71e5b6dd6a21e981ad0fa74359e066f5a8b359)

diff --git a/ChangeLog b/ChangeLog
index 84ae7a7af8d9535c0fb63d8dec7926f0bd367f35..16aa09d97f45817f5bc433baac84ded2ea6532d6 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2016-08-03  Aurelien Jarno  <aurelien@aurel32.net>
+
+       * sysdeps/powerpc/ifunc-sel.h (ifunc_sel): Replace beqlr instructions
+       by beq instructions jumping to the end of the function.
+
 2016-08-04  Carlos O'Donell  <carlos@redhat.com>
 
        * po/de.po: Update from Translation Project.

diff --git a/sysdeps/powerpc/ifunc-sel.h b/sysdeps/powerpc/ifunc-sel.h
index 526d8ed88b2686bb811f42fc43441a3262ecdc77..79d110fef13af29c38ada519570acc9caeaaa446 100644 (file)
--- a/sysdeps/powerpc/ifunc-sel.h
+++ b/sysdeps/powerpc/ifunc-sel.h
@@ -17,13 +17,14 @@ ifunc_sel (int (*f1) (void), int (*f2) (void), int (*f3) (void))
           "addis %0,11,%2-1b@ha\n\t"
           "addi %0,%0,%2-1b@l\n\t"
           "cmpwi 12,1\n\t"
-          "beqlr\n\t"
+          "beq 2f\n\t"
           "addis %0,11,%3-1b@ha\n\t"
           "addi %0,%0,%3-1b@l\n\t"
           "cmpwi 12,-1\n\t"
-          "beqlr\n\t"
+          "beq 2f\n\t"
           "addis %0,11,%4-1b@ha\n\t"
-          "addi %0,%0,%4-1b@l"
+          "addi %0,%0,%4-1b@l\n\t"
+          "2:"
           : "=r" (ret)
           : "X" (&global), "X" (f1), "X" (f2), "X" (f3));
   return ret;