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* [committed] Use branch with link register for jump from thunk
@ 2014-08-11 19:24 John David Anglin
  2014-08-11 19:58 ` John David Anglin
  0 siblings, 1 reply; 2+ messages in thread
From: John David Anglin @ 2014-08-11 19:24 UTC (permalink / raw)
  To: GCC Patches

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With a large function, the 'b' branch may not be able to reach its  
target without a long branch stub.  Gas doesn't provide
a long branch stub for a branch without a link register (i.e., it  
considers branches with link registers calls).  This patch
changes pa_asm_output_mi_thunk() to use a bl branch so the linker will  
provide a long branch stub if needed.

Tested on hppa-unknown-linux-gnu, hppa2.0w-hp-hpux11.11 and hppa64-hp- 
hpux11.11 with no observed regressions.
Committed to trunk, 4.9 and 4.8.

Dave
--
John David Anglin	dave.anglin@bell.net



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2014-08-11  John Dave Anglin  <danglin@gcc.gnu.org>

	PR target/62038
	* config/pa/pa.c (pa_asm_output_mi_thunk): Use a branch with %r31 link
	register.

Index: config/pa/pa.c
===================================================================
--- config/pa/pa.c	(revision 213683)
+++ config/pa/pa.c	(working copy)
@@ -8285,7 +8287,9 @@
       if (!val_14)
 	output_asm_insn ("addil L'%2,%%r26", xoperands);
 
-      output_asm_insn ("b %0", xoperands);
+      /* An absolute branch without a link register is not considered
+	 a call by GAS.  We need a call to get a stub if necessary.  */
+      output_asm_insn ("bl %0,%%r31", xoperands);
 
       if (val_14)
 	{

^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: [committed] Use branch with link register for jump from thunk
  2014-08-11 19:24 [committed] Use branch with link register for jump from thunk John David Anglin
@ 2014-08-11 19:58 ` John David Anglin
  0 siblings, 0 replies; 2+ messages in thread
From: John David Anglin @ 2014-08-11 19:58 UTC (permalink / raw)
  To: John David Anglin; +Cc: GCC Patches

On 11-Aug-14, at 3:24 PM, John David Anglin wrote:

> Tested on hppa-unknown-linux-gnu, hppa2.0w-hp-hpux11.11 and hppa64- 
> hp-hpux11.11 with no observed regressions.
> Committed to trunk, 4.9 and 4.8.

There is a problem...

Patch reverted.

Dave
--
John David Anglin	dave.anglin@bell.net



^ permalink raw reply	[flat|nested] 2+ messages in thread

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