[PATCH] Fix IA-32 TLS IE and LE models (take 2)

[Jakub Jelinek <jakub at redhat dot com>]

On Thu, Aug 08, 2002 at 10:06:33AM -0700, Richard Henderson wrote:
> On Thu, Aug 08, 2002 at 06:26:55PM +0200, Jakub Jelinek wrote:
> > -  tp = gen_rtx_CONST (Pmode, tp);
> > +  tp = gen_rtx_MEM (Pmode, tp);
> > +  RTX_UNCHANGING_P (tp) = 1;
> 
> Do
> 
>   set_mem_alias_set (new, ix86_GOT_alias_set ());
> 
> as well.
> 
> > +/* { dg-do link } */
> > +/* { dg-options "-O2 -ftls-model=initial-exec" } */
> > +/* { dg-options "-O2 -ftls-model=initial-exec -march=i686" { target i?86-*-* } } */
> > +
> > +extern __thread int thr;
> 
> Link?  Where does thr get defined?

Ok, here is the updated patch, bootstrapped/regression tested and
Roland tested glibc build with it.
Ok to commit?

2002-08-08  Jakub Jelinek  <jakub@redhat.com>

	* config/i386/i386.c (legitimate_constant_p): UNSPEC_TP is not
	legitimate constant.
	(legitimate_pic_operand_p): Neither pic operand.
	(legitimate_address_p): But legitimate address.
	(get_thread_pointer): Generate MEM/u instead of CONST around
	UNSPEC_TP.
	(print_operand): Remove printing of UNSPEC_TP.
	(print_operand_address): And print it here.

	* gcc.dg/tls/opt-2.c: New test.

--- gcc/config/i386/i386.c.jj	2002-08-07 22:18:39.000000000 +0200
+++ gcc/config/i386/i386.c	2002-08-08 18:18:18.000000000 +0200
@@ -4850,8 +4850,6 @@ legitimate_constant_p (x)
 	  {
 	  case UNSPEC_TPOFF:
 	    return local_exec_symbolic_operand (XVECEXP (inner, 0, 0), Pmode);
-	  case UNSPEC_TP:
-	    return true;
 	  default:
 	    return false;
 	  }
@@ -4914,8 +4912,6 @@ legitimate_pic_operand_p (x)
 	  {
 	  case UNSPEC_TPOFF:
 	    return local_exec_symbolic_operand (XVECEXP (inner, 0, 0), Pmode);
-	  case UNSPEC_TP:
-	    return true;
 	  default:
 	    return false;
 	  }
@@ -5054,6 +5050,13 @@ legitimate_address_p (mode, addr, strict
       debug_rtx (addr);
     }
 
+  if (GET_CODE (addr) == UNSPEC && XINT (addr, 1) == UNSPEC_TP)
+    {
+      if (TARGET_DEBUG_ADDR)
+	fprintf (stderr, "Success.\n");
+      return TRUE;
+    }
+
   if (ix86_decompose_address (addr, &parts) <= 0)
     {
       reason = "decomposition failed";
@@ -5521,7 +5524,9 @@ get_thread_pointer ()
   rtx tp;
 
   tp = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, const0_rtx), UNSPEC_TP);
-  tp = gen_rtx_CONST (Pmode, tp);
+  tp = gen_rtx_MEM (Pmode, tp);
+  RTX_UNCHANGING_P (tp) = 1;
+  set_mem_alias_set (tp, ix86_GOT_alias_set ());
   tp = force_reg (Pmode, tp);
 
   return tp;
@@ -6611,17 +6615,6 @@ print_operand (file, x, code)
       fprintf (file, "%s", dstr);
     }
 
-  else if (GET_CODE (x) == CONST
-	   && GET_CODE (XEXP (x, 0)) == UNSPEC
-	   && XINT (XEXP (x, 0), 1) == UNSPEC_TP)
-    {
-      if (ASSEMBLER_DIALECT == ASM_INTEL)
-	fputs ("DWORD PTR ", file);
-      if (ASSEMBLER_DIALECT == ASM_ATT || USER_LABEL_PREFIX[0] == 0)
-	putc ('%', file);
-      fputs ("gs:0", file);
-    }
-
   else
     {
       if (code != 'P')
@@ -6660,6 +6653,16 @@ print_operand_address (file, addr)
   rtx base, index, disp;
   int scale;
 
+  if (GET_CODE (addr) == UNSPEC && XINT (addr, 1) == UNSPEC_TP)
+    {
+      if (ASSEMBLER_DIALECT == ASM_INTEL)
+	fputs ("DWORD PTR ", file);
+      if (ASSEMBLER_DIALECT == ASM_ATT || USER_LABEL_PREFIX[0] == 0)
+	putc ('%', file);
+      fputs ("gs:0", file);
+      return;
+    }
+
   if (! ix86_decompose_address (addr, &parts))
     abort ();
 
--- gcc/testsuite/gcc.dg/tls/opt-2.c.jj	2002-08-08 18:36:32.000000000 +0200
+++ gcc/testsuite/gcc.dg/tls/opt-2.c	2002-08-08 18:34:44.000000000 +0200
@@ -0,0 +1,53 @@
+/* This testcase generated invalid assembly on IA-32,
+   since %gs:0 memory load was not exposed to the compiler
+   as memory load and mem to mem moves are not possible
+   on IA-32.  */
+/* { dg-do link } */
+/* { dg-options "-O2 -ftls-model=initial-exec" } */
+/* { dg-options "-O2 -ftls-model=initial-exec -march=i686" { target i?86-*-* } } */
+
+__thread int thr;
+
+struct A
+{
+  unsigned int a, b, c, d, e;
+};
+
+int bar (int x, unsigned long y, void *z)
+{
+  return 0;
+}
+
+int
+foo (int x, int y, const struct A *z)
+{
+  struct A b;
+  int d;
+
+  b = *z;
+  d = bar (x, y, &b);
+  if (d == 0 && y == 0x5402)
+    {
+      int e = thr;
+      d = bar (x, 0x5401, &b);
+      if (d)
+	{
+	  thr = e;
+	  d = 0;
+	}
+      else if ((z->c & 0600) != (b.c & 0600)
+	       || ((z->c & 060) && ((z->c & 060) != (b.c & 060))))
+	{
+	  thr = 22;
+	  d = -1;
+	}
+    }
+
+  return d;
+}
+
+int main (void)
+{
+  foo (1, 2, 0);
+  return 0;
+}


	Jakub