2019-05-22  Bill Schmidt  <wschmidt@linux.ibm.com>
	    Michael Meissner  <meissner@linux.ibm.com>
	    Segher Boessenkool  <segher@kernel.crashing.org>

	* config/rs6000/rs6000-cpus.def (ISA_FUTURE_MASKS_SERVER): Add
	OPTION_MASK_PCREL.
	(POWERPC_MASKS): Add OPTION_MASK_PCREL.
	* config/rs6000/rs6000-protos.h (rs6000_pcrel_p): New prototype.
	(rs6000_fndecl_pcrel_p): Likewise.
	* config/rs6000/rs6000.c (rs6000_option_override_internal): Report
	error if -mpcrel is requested without -mcpu=future.
	(rs6000_opt_masks): Add entry for pcrel.
	(rs6000_fndecl_pcrel_p): New function.
	(rs6000_pcrel_p): Likewise.
	* config/rs6000/rs6000.opt (mpcrel): New option.
	* doc/invoke.texi: Document -mpcrel and -mno-pcrel.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@271575 138bc75d-0d04-0410-961f-82ee72b054a4
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index ff91bfe..3f183fb 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,20 @@
+2019-05-23  Bill Schmidt  <wschmidt@linux.ibm.com>
+	    Michael Meissner  <meissner@linux.ibm.com>
+	    Segher Boessenkool  <segher@kernel.crashing.org>
+
+	* config/rs6000/rs6000-cpus.def (ISA_FUTURE_MASKS_SERVER): Add
+	OPTION_MASK_PCREL.
+	(POWERPC_MASKS): Add OPTION_MASK_PCREL.
+	* config/rs6000/rs6000-protos.h (rs6000_pcrel_p): New prototype.
+	(rs6000_fndecl_pcrel_p): Likewise.
+	* config/rs6000/rs6000.c (rs6000_option_override_internal): Report
+	error if -mpcrel is requested without -mcpu=future.
+	(rs6000_opt_masks): Add entry for pcrel.
+	(rs6000_fndecl_pcrel_p): New function.
+	(rs6000_pcrel_p): Likewise.
+	* config/rs6000/rs6000.opt (mpcrel): New option.
+	* doc/invoke.texi: Document -mpcrel and -mno-pcrel.
+
 2019-05-23  Jan Hubicka  <jh@suse.cz>
 	    Martin Liska  <mliska@suse.cz>
 
diff --git a/gcc/config/rs6000/rs6000-cpus.def b/gcc/config/rs6000/rs6000-cpus.def
index 6220f2b..64292c9 100644
--- a/gcc/config/rs6000/rs6000-cpus.def
+++ b/gcc/config/rs6000/rs6000-cpus.def
@@ -74,7 +74,8 @@
 
 /* Support for a future processor's features.  */
 #define ISA_FUTURE_MASKS_SERVER	(ISA_3_0_MASKS_SERVER			\
-				 | OPTION_MASK_FUTURE)
+				 | OPTION_MASK_FUTURE			\
+				 | OPTION_MASK_PCREL)
 
 /* Flags that need to be turned off if -mno-power9-vector.  */
 #define OTHER_P9_VECTOR_MASKS	(OPTION_MASK_FLOAT128_HW		\
@@ -129,6 +130,7 @@
 				 | OPTION_MASK_P9_MINMAX		\
 				 | OPTION_MASK_P9_MISC			\
 				 | OPTION_MASK_P9_VECTOR		\
+				 | OPTION_MASK_PCREL			\
 				 | OPTION_MASK_POPCNTB			\
 				 | OPTION_MASK_POPCNTD			\
 				 | OPTION_MASK_POWERPC64		\
diff --git a/gcc/config/rs6000/rs6000-protos.h b/gcc/config/rs6000/rs6000-protos.h
index 9718ada..18ece00 100644
--- a/gcc/config/rs6000/rs6000-protos.h
+++ b/gcc/config/rs6000/rs6000-protos.h
@@ -152,6 +152,8 @@
 extern rtx rs6000_allocate_stack_temp (machine_mode, bool, bool);
 extern align_flags rs6000_loop_align (rtx);
 extern void rs6000_split_logical (rtx [], enum rtx_code, bool, bool, bool);
+extern bool rs6000_pcrel_p (struct function *);
+extern bool rs6000_fndecl_pcrel_p (const_tree);
 #endif /* RTX_CODE */
 
 #ifdef TREE_CODE
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 8ad59ec..7a2e43f 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -4296,6 +4296,15 @@
       rs6000_isa_flags &= ~OPTION_MASK_FLOAT128_HW;
     }
 
+  /* -mpcrel requires the prefixed load/store support on FUTURE systems.  */
+  if (!TARGET_FUTURE && TARGET_PCREL)
+    {
+      if ((rs6000_isa_flags_explicit & OPTION_MASK_PCREL) != 0)
+	error ("%qs requires %qs", "-mpcrel", "-mcpu=future");
+
+      rs6000_isa_flags &= ~OPTION_MASK_PCREL;
+    }
+
   /* Print the options after updating the defaults.  */
   if (TARGET_DEBUG_REG || TARGET_DEBUG_TARGET)
     rs6000_print_isa_options (stderr, 0, "after defaults", rs6000_isa_flags);
@@ -36274,6 +36283,7 @@
   { "modulo",			OPTION_MASK_MODULO,		false, true  },
   { "mulhw",			OPTION_MASK_MULHW,		false, true  },
   { "multiple",			OPTION_MASK_MULTIPLE,		false, true  },
+  { "pcrel",			OPTION_MASK_PCREL,		false, true  },
   { "popcntb",			OPTION_MASK_POPCNTB,		false, true  },
   { "popcntd",			OPTION_MASK_POPCNTD,		false, true  },
   { "power8-fusion",		OPTION_MASK_P8_FUSION,		false, true  },
@@ -38113,6 +38123,34 @@
   return (cfun && cfun->machine && cfun->machine->save_toc_in_prologue);
 }
 
+/* Return whether we should generate PC-relative code for FNDECL.  */
+bool
+rs6000_fndecl_pcrel_p (const_tree fndecl)
+{
+  if (DEFAULT_ABI != ABI_ELFv2)
+    return false;
+
+  struct cl_target_option *opts = target_opts_for_fn (fndecl);
+
+  return ((opts->x_rs6000_isa_flags & OPTION_MASK_PCREL) != 0
+	  && TARGET_CMODEL == CMODEL_MEDIUM);
+}
+
+/* Return whether we should generate PC-relative code for *FN.  */
+bool
+rs6000_pcrel_p (struct function *fn)
+{
+  if (DEFAULT_ABI != ABI_ELFv2)
+    return false;
+
+  /* Optimize usual case.  */
+  if (fn == cfun)
+    return ((rs6000_isa_flags & OPTION_MASK_PCREL) != 0
+	    && TARGET_CMODEL == CMODEL_MEDIUM);
+
+  return rs6000_fndecl_pcrel_p (fn->decl);
+}
+
 #ifdef HAVE_GAS_HIDDEN
 # define USE_HIDDEN_LINKONCE 1
 #else
diff --git a/gcc/config/rs6000/rs6000.opt b/gcc/config/rs6000/rs6000.opt
index 196e75d..43b0483 100644
--- a/gcc/config/rs6000/rs6000.opt
+++ b/gcc/config/rs6000/rs6000.opt
@@ -573,3 +573,7 @@
 mfuture
 Target Report Mask(FUTURE) Var(rs6000_isa_flags)
 Use instructions for a future architecture.
+
+mpcrel
+Target Report Mask(PCREL) Var(rs6000_isa_flags)
+Generate (do not generate) pc-relative memory addressing.
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 6164504..4964cc4 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -1121,7 +1121,7 @@
 -mfloat128  -mno-float128  -mfloat128-hardware  -mno-float128-hardware @gol
 -mgnu-attribute  -mno-gnu-attribute @gol
 -mstack-protector-guard=@var{guard} -mstack-protector-guard-reg=@var{reg} @gol
--mstack-protector-guard-offset=@var{offset}}
+-mstack-protector-guard-offset=@var{offset} -mpcrel -mno-pcrel}
 
 @emph{RX Options}
 @gccoptlist{-m64bit-doubles  -m32bit-doubles  -fpu  -nofpu@gol
@@ -25095,6 +25095,13 @@
 offset from that base register. The default for those is as specified in the
 relevant ABI.  @option{-mstack-protector-guard-symbol=@var{symbol}} overrides
 the offset with a symbol reference to a canary in the TLS block.
+
+@item -mpcrel
+@itemx -mno-pcrel
+@opindex mpcrel
+@opindex mno-pcrel
+Generate (do not generate) pc-relative addressing when the option
+@option{-mcpu=future} is used.
 @end table
 
 @node RX Options