diff mbox

[05/10] addr32: Load TP into register for TLS_MODEL_LOCAL_EXEC modes in x32

Message ID 20120302205603.GC2179@intel.com
State New
Headers show

Commit Message

H.J. Lu March 2, 2012, 8:56 p.m. UTC 
Hi,

Since the 0x67 address prefix only zeros out the upper 32bits of the
(reg) part in address fs:(reg), we can't use fs:(reg) as memory operand
for x32 with Pmode == SImode.  We have to load the address into a
register first and use it as memory operand.  Tested on Linux/x86-64.
OK for trunk?

Thanks.


H.J.
2012-03-02  H.J. Lu  <hongjiu.lu@intel.com>
 
	* config/i386/i386.c (legitimize_tls_address): Load TP into
	register for TLS_MODEL_LOCAL_EXEC modes in x32.

Comments

Uros Bizjak March 5, 2012, 9:05 a.m. UTC | #1 
On Fri, Mar 2, 2012 at 9:56 PM, H.J. Lu <hongjiu.lu@intel.com> wrote:

> Since the 0x67 address prefix only zeros out the upper 32bits of the
> (reg) part in address fs:(reg), we can't use fs:(reg) as memory operand
> for x32 with Pmode == SImode.  We have to load the address into a
> register first and use it as memory operand.  Tested on Linux/x86-64.
> OK for trunk?

This patch won't be needed when TARGET_TLS_DIRECT_SEG_REFS will be
cleared, as suggested in [1].

[1] http://gcc.gnu.org/ml/gcc-patches/2012-03/msg00252.html

Uros.
diff mbox

Patch

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 7cb8fda..d6ec6ff 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -12687,7 +12687,16 @@  legitimize_tls_address (rtx x, enum tls_model model, bool for_mov)
       if (TARGET_64BIT || TARGET_ANY_GNU_TLS)
 	{
 	  base = get_thread_pointer (for_mov || !TARGET_TLS_DIRECT_SEG_REFS);
-	  return gen_rtx_PLUS (Pmode, base, off);
+	  if (Pmode != word_mode)
+	    {
+	      /* Since address override works only on the (reg) part in
+		 fs:(reg), we can't use it as memory operand.  */
+	      rtx reg = gen_reg_rtx (Pmode);
+	      emit_move_insn (reg, base);
+	      return gen_rtx_PLUS (Pmode, reg, off);
+	    }
+	  else
+	    return gen_rtx_PLUS (Pmode, base, off);
 	}
       else
 	{