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-rw-r--r--ChangeLog6
-rw-r--r--sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S8
-rw-r--r--sysdeps/unix/sysv/linux/powerpc/powerpc64/makecontext.S6
3 files changed, 16 insertions, 4 deletions
diff --git a/ChangeLog b/ChangeLog
index ec81a6b817..07aaa256d3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 2013-10-04  Alan Modra  <amodra@gmail.com>
 
+	* sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S: Use
+	conditional form of branch and link when obtaining pc.
+	* sysdeps/unix/sysv/linux/powerpc/powerpc64/makecontext.S: Likewise.
+
+2013-10-04  Alan Modra  <amodra@gmail.com>
+
 	* sysdeps/unix/sysv/linux/powerpc/powerpc32/getcontext-common.S: Use
 	HIWORD/LOWORD.
 	* sysdeps/unix/sysv/linux/powerpc/powerpc32/setcontext-common.S: Ditto.
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S b/sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S
index 95902b13f9..70e3c97626 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/makecontext.S
@@ -47,7 +47,9 @@ ENTRY(__makecontext)
 #ifdef PIC
 	mflr	r0
 	cfi_register(lr,r0)
-	bl	1f
+	/* Use this conditional form of branch and link to avoid destroying
+	   the cpu link stack used to predict blr return addresses.  */
+	bcl	20,31,1f
 1:	mflr	r6
 	addi	r6,r6,L(exitcode)-1b
 	mtlr	r0
@@ -136,7 +138,9 @@ ENTRY(__novec_makecontext)
 #ifdef PIC
 	mflr	r0
 	cfi_register(lr,r0)
-	bl	1f
+	/* Use this conditional form of branch and link to avoid destroying
+	   the cpu link stack used to predict blr return addresses.  */
+	bcl	20,31,1f
 1:	mflr	r6
 	addi	r6,r6,L(novec_exitcode)-1b
 	mtlr	r0
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/makecontext.S b/sysdeps/unix/sysv/linux/powerpc/powerpc64/makecontext.S
index 4a16669383..32fc47c3f3 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/makecontext.S
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/makecontext.S
@@ -124,8 +124,10 @@ L(noparms):
 
   /* If the target function returns we need to do some cleanup.  We use a
      code trick to get the address of our cleanup function into the link
-     register.  Do not add any code between here and L(exitcode).  */
-  bl  L(gotexitcodeaddr);
+     register.  Do not add any code between here and L(exitcode).
+     Use this conditional form of branch and link to avoid destroying
+     the cpu link stack used to predict blr return addresses.  */
+  bcl	20,31,L(gotexitcodeaddr);
 
 	/* This is the helper code which gets called if a function which
 	   is registered with 'makecontext' returns.  In this case we