From: Jeff Law <law@redhat.com>
Date: Thu, 17 Nov 2016 23:39:08 +0000 (-0700)
Subject: re PR target/47192 (m68k target - gcc uses stack frame after it has been unlinked... 
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=f2b6aad987ce2828f9b157a70bf76fada97a0a30;p=gcc.git

re PR target/47192 (m68k target - gcc uses stack frame after it has been unlinked when compiling with -Os)

	PR target/47192
	* config/m68k/m68k.c (m68k_expand_epilogue): Emit a scheduling
	barrier prior to deallocating the stack.

	PR target/47192
	* gcc.target/m68k/pr47192.c: New test.

From-SVN: r242575
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 24ed0f89b9e..86a8fdf7d76 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2016-11-17  Jeff Law  <law@redhat.com>
+
+	PR target/47192
+	* config/m68k/m68k.c (m68k_expand_epilogue): Emit a scheduling
+	barrier prior to deallocating the stack.
+
 2016-11-17  Andrew Burgess  <andrew.burgess@embecosm.com>
 
 	* config/arc/arc.md (cmem bit/sign-extend peephole2): New peephole
diff --git a/gcc/config/m68k/m68k.c b/gcc/config/m68k/m68k.c
index ce566926496..346c2dc6af3 100644
--- a/gcc/config/m68k/m68k.c
+++ b/gcc/config/m68k/m68k.c
@@ -1205,6 +1205,7 @@ m68k_expand_epilogue (bool sibcall_p)
 	     stack-based restore.  */
 	  emit_move_insn (gen_rtx_REG (Pmode, A1_REG),
 			  GEN_INT (-(current_frame.offset + fsize)));
+	  emit_insn (gen_blockage ());
 	  emit_insn (gen_addsi3 (stack_pointer_rtx,
 				 gen_rtx_REG (Pmode, A1_REG),
 				 frame_pointer_rtx));
@@ -1306,6 +1307,7 @@ m68k_expand_epilogue (bool sibcall_p)
 			 current_frame.fpu_mask, false, false);
     }
 
+  emit_insn (gen_blockage ());
   if (frame_pointer_needed)
     emit_insn (gen_unlink (frame_pointer_rtx));
   else if (fsize_with_regs)
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 356d75aab42..5dd6f569a22 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2016-11-17  Jeff Law  <law@redhat.com>
+
+	PR target/47192
+	* gcc.target/m68k/pr47192.c: New test.
+
 2016-11-17  Toma Tabacu  <toma.tabacu@imgtec.com>
 
 	* gcc.target/mips/branch-cost-1.c (dg-options): Use (HAS_MOVN)
diff --git a/gcc/testsuite/gcc.target/m68k/pr47192.c b/gcc/testsuite/gcc.target/m68k/pr47192.c
new file mode 100644
index 00000000000..5bbef586632
--- /dev/null
+++ b/gcc/testsuite/gcc.target/m68k/pr47192.c
@@ -0,0 +1,36 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -mcpu=51qe -fdisable-ipa-pure-const -fdump-rtl-pro_and_epilogue" } */
+/* { dg-final { scan-rtl-dump-times "unspec_volatile" 1 "pro_and_epilogue"} } */
+
+
+char F(short *ty);
+
+short V(char cmd)
+{
+  static short st256;
+  static short stc;
+  short sc;
+  short scd;
+  short d;
+
+  F(&sc);
+
+  if (cmd == 4)
+  {
+    st256 = 0;
+    d = 0;
+  }
+  else
+  {
+    scd = sc - stc;
+    if (scd < -128)
+    {
+      scd += 256;
+    }
+    d = st256 >> 8;
+    st256 -= d << 8;
+  }
+  stc = sc;
+  return d;
+}
+