Patchwork x86_64 -mcmodel={medium,large} -fpic address delegitimization

login
register
mail settings
Submitter Jakub Jelinek
Date Aug. 13, 2013, 7:47 p.m.
Message ID <20130813194710.GK1814@tucnak.redhat.com>
Download mbox | patch
Permalink /patch/266911/
State New
Headers show

Comments

Jakub Jelinek - Aug. 13, 2013, 7:47 p.m.
Hi!

On x86_64 with -mcmodel=large -fpic -g -O2 we get tons of
notes about non-delegitimized unspecs like UNSPEC_GOTOFF, UNSPEC_PLTOFF
or UNSPEC_GOT.  Seems we already handle most of those properly for -m32
code, so the issue is just that we wouldn't fall back into the -m32 handling
code which takes care of dealing with addends, missing pic pointer etc.
The following patch inverts the last condition for TARGET_64BIT code
and falls through for CM_MEDIUM_PIC and CM_LARGE_PIC cmodels.

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2013-08-13  Jakub Jelinek  <jakub@redhat.com>
	    Alexandre Oliva  <aoliva@redhat.com>

	PR target/58067
	* config/i386/i386.c (ix86_delegitimize_address): For CM_MEDIUM_PIC
	and CM_LARGE_PIC ix86_cmodel fall thru into the -m32 code, handle
	there also UNSPEC_PLTOFF.


	Jakub
Uros Bizjak - Aug. 14, 2013, 7:05 a.m.
On Tue, Aug 13, 2013 at 9:47 PM, Jakub Jelinek <jakub@redhat.com> wrote:

> On x86_64 with -mcmodel=large -fpic -g -O2 we get tons of
> notes about non-delegitimized unspecs like UNSPEC_GOTOFF, UNSPEC_PLTOFF
> or UNSPEC_GOT.  Seems we already handle most of those properly for -m32
> code, so the issue is just that we wouldn't fall back into the -m32 handling
> code which takes care of dealing with addends, missing pic pointer etc.
> The following patch inverts the last condition for TARGET_64BIT code
> and falls through for CM_MEDIUM_PIC and CM_LARGE_PIC cmodels.
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
>
> 2013-08-13  Jakub Jelinek  <jakub@redhat.com>
>             Alexandre Oliva  <aoliva@redhat.com>
>
>         PR target/58067
>         * config/i386/i386.c (ix86_delegitimize_address): For CM_MEDIUM_PIC
>         and CM_LARGE_PIC ix86_cmodel fall thru into the -m32 code, handle
>         there also UNSPEC_PLTOFF.

OK, also for backport to other release branches.

Thanks,
Uros.

Patch

--- gcc/config/i386/i386.c.jj	2013-08-13 14:42:32.000000000 +0200
+++ gcc/config/i386/i386.c	2013-08-13 18:49:25.514219094 +0200
@@ -14135,21 +14135,29 @@  ix86_delegitimize_address (rtx x)
 	    x = replace_equiv_address_nv (orig_x, x);
 	  return x;
 	}
-      if (GET_CODE (x) != CONST
-	  || GET_CODE (XEXP (x, 0)) != UNSPEC
-	  || (XINT (XEXP (x, 0), 1) != UNSPEC_GOTPCREL
-	      && XINT (XEXP (x, 0), 1) != UNSPEC_PCREL)
-	  || (!MEM_P (orig_x) && XINT (XEXP (x, 0), 1) != UNSPEC_PCREL))
-	return ix86_delegitimize_tls_address (orig_x);
-      x = XVECEXP (XEXP (x, 0), 0, 0);
-      if (GET_MODE (orig_x) != GET_MODE (x) && MEM_P (orig_x))
+
+      if (GET_CODE (x) == CONST
+	  && GET_CODE (XEXP (x, 0)) == UNSPEC
+	  && (XINT (XEXP (x, 0), 1) == UNSPEC_GOTPCREL
+	      || XINT (XEXP (x, 0), 1) == UNSPEC_PCREL)
+	  && (MEM_P (orig_x) || XINT (XEXP (x, 0), 1) == UNSPEC_PCREL))
 	{
-	  x = simplify_gen_subreg (GET_MODE (orig_x), x,
-				   GET_MODE (x), 0);
-	  if (x == NULL_RTX)
-	    return orig_x;
+	  x = XVECEXP (XEXP (x, 0), 0, 0);
+	  if (GET_MODE (orig_x) != GET_MODE (x) && MEM_P (orig_x))
+	    {
+	      x = simplify_gen_subreg (GET_MODE (orig_x), x,
+				       GET_MODE (x), 0);
+	      if (x == NULL_RTX)
+		return orig_x;
+	    }
+	  return x;
 	}
-      return x;
+
+      if (ix86_cmodel != CM_MEDIUM_PIC && ix86_cmodel != CM_LARGE_PIC)
+	return ix86_delegitimize_tls_address (orig_x);
+
+      /* Fall thru into the code shared with -m32 for -mcmodel=large -fpic
+	 and -mcmodel=medium -fpic.  */
     }
 
   if (GET_CODE (x) != PLUS
@@ -14186,10 +14194,12 @@  ix86_delegitimize_address (rtx x)
 
   if (GET_CODE (x) == UNSPEC
       && ((XINT (x, 1) == UNSPEC_GOT && MEM_P (orig_x) && !addend)
-	  || (XINT (x, 1) == UNSPEC_GOTOFF && !MEM_P (orig_x))))
+	  || (XINT (x, 1) == UNSPEC_GOTOFF && !MEM_P (orig_x))
+	  || (XINT (x, 1) == UNSPEC_PLTOFF && ix86_cmodel == CM_LARGE_PIC
+	      && !MEM_P (orig_x) && !addend)))
     result = XVECEXP (x, 0, 0);
 
-  if (TARGET_MACHO && darwin_local_data_pic (x)
+  if (!TARGET_64BIT && TARGET_MACHO && darwin_local_data_pic (x)
       && !MEM_P (orig_x))
     result = XVECEXP (x, 0, 0);