Update pc-relative support.

2019-06-28  Michael Meissner  <meissner@linux.ibm.com>

	* config/rs6000/predicates.md (pcrel_address):  Use
	SYMBOL_REF_LOCAL_P to determine if a label is local.
	(pcrel_external_address): New predicate.
	(non_prefixed_mem_operand): Delete, predicate not used.
	* config/rs6000/rs6000.h (SYMBOL_FLAG_PCREL_P): Delete, we now use
	SYMBOL_REF_LOCAL_P to determine if we can use pc-relative
	addressing.
	(SYMBOL_REF_PCREL_P): Likewise.

From-SVN: r272792

gcc/ChangeLog

 2019-06-28   Michael Meissner  <meissner@linux.ibm.com>
 
+	* config/rs6000/predicates.md (pcrel_address):  Use
+	SYMBOL_REF_LOCAL_P to determine if a label is local.
+	(pcrel_external_address): New predicate.
+	(non_prefixed_mem_operand): Delete, predicate not used.
+	* config/rs6000/rs6000.h (SYMBOL_FLAG_PCREL_P): Delete, we now use
+	SYMBOL_REF_LOCAL_P to determine if we can use pc-relative
+	addressing.
+	(SYMBOL_REF_PCREL_P): Likewise.
+
 	PR target/91009
 	* config/rs6000/rs6000.md (floatsi<mode>2_lfiwax): Add non-VSX
 	alternative.

gcc/config/rs6000/predicates.md

@@ -1626,10 +1626,9 @@
 (define_predicate "pcrel_address"
   (match_code "label_ref,symbol_ref,const")
 {
-  if (!TARGET_PCREL)
+  if (!rs6000_pcrel_p (cfun))
     return false;
 
-  /* Discard any CONST's.  */
   if (GET_CODE (op) == CONST)
     op = XEXP (op, 0);
 
@@ -1645,21 +1644,59 @@
       op = op0;
     }
 
-  return LABEL_REF_P (op) || SYMBOL_REF_PCREL_P (op);
+  if (LABEL_REF_P (op))
+    return true;
+
+  return (SYMBOL_REF_P (op) && SYMBOL_REF_LOCAL_P (op));
+})
+
+;; Return true if the operand is an external symbol whose address can be loaded
+;; into a register using:
+;;	PLA reg,label@pcrel@got
+;;
+;; The linker will either optimize this to either a PADDI if the label is
+;; defined locally in another module or a PLD of the address if the label is
+;; defined in another module.
+
+(define_predicate "pcrel_external_address"
+  (match_code "symbol_ref,const")
+{
+  if (!rs6000_pcrel_p (cfun))
+    return false;
+
+  if (GET_CODE (op) == CONST)
+    op = XEXP (op, 0);
+
+  /* Validate offset.  */
+  if (GET_CODE (op) == PLUS)
+    {
+      rtx op0 = XEXP (op, 0);
+      rtx op1 = XEXP (op, 1);
+
+      if (!CONST_INT_P (op1) || !SIGNED_34BIT_OFFSET_P (INTVAL (op1), 0))
+	return false;
+
+      op = op0;
+    }
+
+  return (SYMBOL_REF_P (op) && !SYMBOL_REF_LOCAL_P (op));
 })
 
-;; Return 1 if op is a prefixed memory operand
+;; Return 1 if op is a prefixed memory operand.
 (define_predicate "prefixed_mem_operand"
   (match_code "mem")
 {
   return rs6000_prefixed_address (XEXP (op, 0), GET_MODE (op));
 })
 
-;; Return 1 if op is a memory operand that is not a prefixed memory
-;; operand.
-(define_predicate "non_prefixed_mem_operand"
-  (and (match_operand 0 "memory_operand")
-       (not (match_operand 0 "prefixed_mem_operand"))))
+;; Return 1 if op is a memory operand to an external variable when we
+;; support pc-relative addressing and the PCREL_OPT relocation to
+;; optimize references to it.
+(define_predicate "pcrel_external_mem_operand"
+  (match_code "mem")
+{
+  return pcrel_external_address (XEXP (op, 0), Pmode);
+})
 
 ;; Match the first insn (addis) in fusing the combination of addis and loads to
 ;; GPR registers on power8.

gcc/config/rs6000/rs6000.h

@@ -2539,10 +2539,3 @@ typedef struct GTY(()) machine_function
   IN_RANGE (VALUE,							\
 	    -(HOST_WIDE_INT_1 << 33),					\
 	    (HOST_WIDE_INT_1 << 33) - 1 - (EXTRA))
-
-/* Flag to mark SYMBOL_REF objects to say they are local addresses and are used
-   in pc-relative addresses.  */
-#define SYMBOL_FLAG_PCREL	SYMBOL_FLAG_MACH_DEP
-
-#define SYMBOL_REF_PCREL_P(X)						\
-  (SYMBOL_REF_P (X) && SYMBOL_REF_FLAGS (X) & SYMBOL_FLAG_PCREL)