2017-06-28  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	* config/s390/predicates.md: Use s390_rel_address_ok_p.

	* config/s390/s390-protos.h: Add prototype of

	s390_rel_address_ok_p.

	* config/s390/s390.c (s390_got_symbol): New function.

	(s390_rel_address_ok_p): New function.

	(legitimize_pic_address): Use s390_rel_address_ok_p.

	(s390_load_got): Use s390_got_symbol.

	(s390_option_override): Issue error if

	-mno-pic-data-is-text-relative is used without -fpic/-fPIC.

	* config/s390/s390.h (TARGET_DEFAULT_PIC_DATA_IS_TEXT_RELATIVE):

	New macro.

	* config/s390/s390.opt: New option mpic-data-is-text-relative.

--- gcc/config/s390/predicates.md	2013-08-14 07:55:12.000000000 -0400

+++ gcc/config/s390/predicates.md	2018-04-09 21:36:49.428209951 -0400

@@ -116,7 +116,7 @@

   if (GET_CODE (op) == SYMBOL_REF)

     return (!SYMBOL_REF_ALIGN1_P (op)

 	    && SYMBOL_REF_TLS_MODEL (op) == 0

-	    && (!flag_pic || SYMBOL_REF_LOCAL_P (op)));

+	    && s390_rel_address_ok_p (op));

   /* Everything else must have a CONST, so strip it.  */

   if (GET_CODE (op) != CONST)

@@ -141,7 +141,7 @@

   if (GET_CODE (op) == SYMBOL_REF)

     return ((SYMBOL_REF_FLAGS (op) & SYMBOL_FLAG_ALIGN1) == 0

 	    && SYMBOL_REF_TLS_MODEL (op) == 0

-	    && (!flag_pic || SYMBOL_REF_LOCAL_P (op)));

+	    && s390_rel_address_ok_p (op));

   /* Now we must have a @GOTENT offset or @PLT stub

      or an @INDNTPOFF TLS offset.  */

--- gcc/config/s390/s390.c	2015-06-18 10:33:04.000000000 -0400

+++ gcc/config/s390/s390.c	2018-04-09 21:32:43.489851529 -0400

@@ -491,6 +491,23 @@ s390_label_align (rtx label)

   return align_labels_log;

 }

+static GTY(()) rtx got_symbol;

+

+/* Return the GOT table symbol.  The symbol will be created when the

+   function is invoked for the first time.  */

+

+static rtx

+s390_got_symbol (void)

+{

+  if (!got_symbol)

+    {

+      got_symbol = gen_rtx_SYMBOL_REF (Pmode, "_GLOBAL_OFFSET_TABLE_");

+      SYMBOL_REF_FLAGS (got_symbol) = SYMBOL_FLAG_LOCAL;

+    }

+

+  return got_symbol;

+}

+

 static enum machine_mode

 s390_libgcc_cmp_return_mode (void)

 {

@@ -1863,6 +1880,9 @@ s390_option_override (void)

   if (flag_prefetch_loop_arrays < 0 && HAVE_prefetch && optimize >= 3)

     flag_prefetch_loop_arrays = 1;

+  if (!s390_pic_data_is_text_relative && !flag_pic)

+    error ("-mno-pic-data-is-text-relative cannot be used without -fpic/-fPIC");

+

   /* Use the alternative scheduling-pressure algorithm by default.  */

   maybe_set_param_value (PARAM_SCHED_PRESSURE_ALGORITHM, 2,

                          global_options.x_param_values,

@@ -3557,6 +3577,26 @@ s390_load_address (rtx dst, rtx src)

     emit_insn (gen_force_la_31 (dst, src));

 }

+/* Return true if it ok to use SYMBOL_REF in a relative address.  */

+

+bool

+s390_rel_address_ok_p (rtx symbol_ref)

+{

+  tree decl;

+

+  if (symbol_ref == s390_got_symbol () || CONSTANT_POOL_ADDRESS_P (symbol_ref))

+    return true;

+

+  decl = SYMBOL_REF_DECL (symbol_ref);

+

+  if (!flag_pic || SYMBOL_REF_LOCAL_P (symbol_ref))

+    return (s390_pic_data_is_text_relative

+	    || (decl

+		&& TREE_CODE (decl) == FUNCTION_DECL));

+

+  return false;

+}

+

 /* Return a legitimate reference for ORIG (an address) using the

    register REG.  If REG is 0, a new pseudo is generated.

@@ -3594,7 +3634,7 @@ legitimize_pic_address (rtx orig, rtx re

     }

   if ((GET_CODE (addr) == LABEL_REF

-       || (GET_CODE (addr) == SYMBOL_REF && SYMBOL_REF_LOCAL_P (addr))

+       || (GET_CODE (addr) == SYMBOL_REF && s390_rel_address_ok_p (addr))

        || (GET_CODE (addr) == UNSPEC &&

 	   (XINT (addr, 1) == UNSPEC_GOTENT

 	    || (TARGET_CPU_ZARCH && XINT (addr, 1) == UNSPEC_PLT))))

@@ -8545,7 +8585,6 @@ restore_gprs (rtx base, int offset, int

 /* Return insn sequence to load the GOT register.  */

-static GTY(()) rtx got_symbol;

 rtx

 s390_load_got (void)

 {

@@ -8557,23 +8596,17 @@ s390_load_got (void)

      aren't usable.  */

   rtx got_rtx = gen_rtx_REG (Pmode, 12);

-  if (!got_symbol)

-    {

-      got_symbol = gen_rtx_SYMBOL_REF (Pmode, "_GLOBAL_OFFSET_TABLE_");

-      SYMBOL_REF_FLAGS (got_symbol) = SYMBOL_FLAG_LOCAL;

-    }

-

   start_sequence ();

   if (TARGET_CPU_ZARCH)

     {

-      emit_move_insn (got_rtx, got_symbol);

+      emit_move_insn (got_rtx, s390_got_symbol ());

     }

   else

     {

       rtx offset;

-      offset = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, got_symbol),

+      offset = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, s390_got_symbol ()),

 			       UNSPEC_LTREL_OFFSET);

       offset = gen_rtx_CONST (Pmode, offset);

       offset = force_const_mem (Pmode, offset);

--- gcc/config/s390/s390.h	2014-01-14 10:37:03.000000000 -0500

+++ gcc/config/s390/s390.h	2018-04-09 21:21:28.076858052 -0400

@@ -814,6 +814,10 @@ do {									\

 #define LEGITIMATE_PIC_OPERAND_P(X)  legitimate_pic_operand_p (X)

+#ifndef TARGET_DEFAULT_PIC_DATA_IS_TEXT_RELATIVE

+#define TARGET_DEFAULT_PIC_DATA_IS_TEXT_RELATIVE 1

+#endif

+

 /* Assembler file format.  */

--- gcc/config/s390/s390.opt	2015-06-18 10:33:05.000000000 -0400

+++ gcc/config/s390/s390.opt	2018-04-09 21:28:18.842465842 -0400

@@ -158,6 +158,10 @@ mzarch

 Target Report RejectNegative Negative(mesa) Mask(ZARCH)

 z/Architecture

+mpic-data-is-text-relative

+Target Report Var(s390_pic_data_is_text_relative) Init(TARGET_DEFAULT_PIC_DATA_IS_TEXT_RELATIVE)

+Assume data segments are relative to text segment.

+

 mbranch-cost=

 Target Report Joined RejectNegative UInteger Var(s390_branch_cost) Init(1)

 Set the branch costs for conditional branch instructions.  Reasonable

--- gcc/config/s390/s390-protos.h	2014-01-14 10:37:04.000000000 -0500

+++ gcc/config/s390/s390-protos.h	2018-04-09 21:21:28.072858046 -0400

@@ -52,6 +52,7 @@ extern bool s390_contiguous_bitmask_p (u

 extern bool s390_split_ok_p (rtx, rtx, enum machine_mode, int);

 extern bool s390_overlap_p (rtx, rtx, HOST_WIDE_INT);

 extern bool s390_offset_p (rtx, rtx, rtx);

+extern bool s390_rel_address_ok_p (rtx);

 extern int tls_symbolic_operand (rtx);

 extern bool s390_match_ccmode (rtx, enum machine_mode);

--- gcc/testsuite/gcc.target/s390/nodatarel-1.c	1969-12-31 19:00:00.000000000 -0500

+++ gcc/testsuite/gcc.target/s390/nodatarel-1.c	2018-04-09 21:21:28.077858053 -0400

@@ -0,0 +1,83 @@

+/* Test -mno-pic-data-is-text-relative option.  No relative addressing

+   of elements in .data and .bss are allowed with that option.  */

+

+/* { dg-do compile } */

+/* { dg-options "-O3 -fno-optimize-sibling-calls -fpic -mno-pic-data-is-text-relative -march=z10 -mtune=z9-109 -mzarch" } */

+

+static int a = 3;

+

+/* With -mno-pic-data-is-text-relative these must be addressed via

+   GOT.  */

+

+int __attribute__((noinline,noclone))

+foo ()

+{

+  return a;

+}

+

+static int __attribute__((noinline,noclone))

+foostatic (void)

+{

+  return a;

+}

+

+/* Just to make a potentially modified.  */

+

+void

+bar (int b)

+{

+  a = b;

+}

+

+/* { dg-final { scan-assembler-times "a@GOTENT" 3 } } */

+

+/* The exrl target is a label_ref which should not be affected at

+   all.  */

+

+void

+mymemcpy (char *dst, char *src, long size)

+{

+  __builtin_memcpy (dst, src, size);

+}

+

+/* { dg-final { scan-assembler "exrl" } } */

+

+

+/* PLT slots can still be addressed relatively.  */

+

+int

+callfoo ()

+{

+  return foo ();

+}

+

+/* { dg-final { scan-assembler-times "foo@PLT" 1 } } */

+

+

+/* GOT entries can still be addressed relatively.  */

+

+void *

+fooptr ()

+{

+  return &foo;

+}

+

+/* { dg-final { scan-assembler-times "foo@GOTENT" 1 } } */

+

+

+/* A static function can be addressed relatively.  */

+

+int

+callfoostatic ()

+{

+  return foostatic ();

+}

+

+void *

+foostaticptr ()

+{

+  return &foostatic;

+}

+

+

+/* { dg-final { scan-assembler-not "foostatic@" } } */