From: Alan Modra <amodra@gmail.com>
Date: Sat, 9 Feb 2019 12:44:02 +0000 (+1030)
Subject: [RS6000] Correct save_reg_p
X-Git-Tag: releases/gcc-7.5.0~599
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e08292047c4a856470bce333929e93fee4ec19d4;p=thirdparty%2Fgcc.git

[RS6000] Correct save_reg_p

	PR target/88343
	* config/rs6000/rs6000.c (rs6000_reg_live_or_pic_offset_p): Match
	logic in rs6000_emit_prologue emitting pic_offset_table setup.

From-SVN: r268722
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 91dbf9962adf..9e73034f085b 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2019-02-09  Alan Modra  <amodra@gmail.com>
+
+	PR target/88343
+	* config/rs6000/rs6000.c (rs6000_reg_live_or_pic_offset_p): Match
+	logic in rs6000_emit_prologue emitting pic_offset_table setup.
+
 2019-02-08  Eric Botcazou  <ebotcazou@adacore.com>
 
 	Backport from mainline
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 68dd95429fe6..f31a8b83a759 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -26726,27 +26726,35 @@ save_reg_p (int r)
 static bool
 rs6000_reg_live_or_pic_offset_p (int reg)
 {
-  /* We need to mark the PIC offset register live for the same conditions
-     as it is set up, or otherwise it won't be saved before we clobber it.  */
-
   if (reg == RS6000_PIC_OFFSET_TABLE_REGNUM && !TARGET_SINGLE_PIC_BASE)
     {
+      /* When calling eh_return, we must return true for all the cases
+	 where conditional_register_usage marks the PIC offset reg
+	 call used or fixed.  */
+      if (crtl->calls_eh_return
+	  && ((DEFAULT_ABI == ABI_V4 && flag_pic)
+	      || (DEFAULT_ABI == ABI_DARWIN && flag_pic)
+	      || (TARGET_TOC && TARGET_MINIMAL_TOC)))
+	return true;
+
+      /* We need to mark the PIC offset register live for the same
+	 conditions as it is set up in rs6000_emit_prologue, or
+	 otherwise it won't be saved before we clobber it.  */
       if (TARGET_TOC && TARGET_MINIMAL_TOC
-	  && (crtl->calls_eh_return
-	      || df_regs_ever_live_p (reg)
-	      || !constant_pool_empty_p ()))
+	  && !constant_pool_empty_p ())
 	return true;
 
-      if ((DEFAULT_ABI == ABI_V4 || DEFAULT_ABI == ABI_DARWIN)
-	  && flag_pic)
+      if (DEFAULT_ABI == ABI_V4
+	  && (flag_pic == 1 || (flag_pic && TARGET_SECURE_PLT))
+	  && df_regs_ever_live_p (RS6000_PIC_OFFSET_TABLE_REGNUM))
 	return true;
-    }
 
-  /* If the function calls eh_return, claim used all the registers that would
-     be checked for liveness otherwise.  */
+      if (DEFAULT_ABI == ABI_DARWIN
+	  && flag_pic && crtl->uses_pic_offset_table)
+	return true;
+    }
 
-  return ((crtl->calls_eh_return || df_regs_ever_live_p (reg))
-	  && !call_used_regs[reg]);
+  return !call_used_regs[reg] && df_regs_ever_live_p (reg);
 }
 
 /* Return the first fixed-point register that is required to be