From: Jeffrey A Law <law@cygnus.com>
Date: Tue, 23 Jan 2001 03:52:54 +0000 (+0000)
Subject: pa.md (return_internal): Add a USE of the PIC register to ensure it is restored after... 
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=2caa0ddfc92ef326520e9e2467297435ecdf99e5;p=gcc.git

pa.md (return_internal): Add a USE of the PIC register to ensure it is restored after each call.

        * pa.md (return_internal): Add a USE of the PIC register to ensure
        it is restored after each call.
        (return expander): Corresponding changes.

From-SVN: r39193
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 26d488d3518..7ab2abcf79e 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+Mon Jan 22 20:53:47 2001  Jeffrey A Law  (law@cygnus.com)
+
+	* pa.md (return_internal): Add a USE of the PIC register to ensure
+	it is restored after each call.
+	(return expander): Corresponding changes.
+
 2001-01-22  Franz Sirl  <Franz.Sirl-kernel@lauterbach.com>
 
 	* rs6000.h (INIT_EXPANDERS): Delete.
diff --git a/gcc/config/pa/pa.md b/gcc/config/pa/pa.md
index 7179c01a1e4..2d71c7f76b1 100644
--- a/gcc/config/pa/pa.md
+++ b/gcc/config/pa/pa.md
@@ -5466,6 +5466,8 @@
 
 ;; Unconditional and other jump instructions.
 
+;; This can only be used in a leaf function, so we do
+;; not need to use the PIC register.
 (define_insn "return"
   [(return)
    (use (reg:SI 2))
@@ -5482,11 +5484,16 @@
 
 ;; Use a different pattern for functions which have non-trivial
 ;; epilogues so as not to confuse jump and reorg.
+;;
+;; We use the PIC register to ensure it's restored after a
+;; call in PIC mode.  This can be non-optimal for non-PIC
+;; code but the real world cost should be unmeasurable.
 (define_insn "return_internal"
   [(return)
+   (use (match_operand:SI 0 "register_operand" "r"))
    (use (reg:SI 2))
    (const_int 1)]
-  ""
+  "true_regnum (operands[0]) == PIC_OFFSET_TABLE_REGNUM"
   "*
 {
   if (TARGET_PA_20)
@@ -5521,8 +5528,12 @@
    emit_jump_insn (gen_return ());
   else
     {
+      rtx x;
+
       hppa_expand_epilogue ();
-      emit_jump_insn (gen_return_internal ());
+      x = gen_return_internal (gen_rtx_REG (word_mode,
+					    PIC_OFFSET_TABLE_REGNUM));
+      emit_jump_insn (x);
     }
   DONE;
 }")