From: Jeff Law <law@gcc.gnu.org>
Date: Mon, 15 Aug 1994 01:55:59 +0000 (-0600)
Subject: pa.c (hppa_expand_prologue): Avoid writing outside the current stack boundary in... 
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=2ebb1b42179408831331556fb977d188eb2f3574;p=gcc.git

pa.c (hppa_expand_prologue): Avoid writing outside the current stack boundary in code to handle large stack...

	* pa.c (hppa_expand_prologue): Avoid writing outside the current
	stack boundary in code to handle large stack frames.

From-SVN: r7926
---

diff --git a/gcc/config/pa/pa.c b/gcc/config/pa/pa.c
index 2ec1d8b33e5..6adca1b23b8 100644
--- a/gcc/config/pa/pa.c
+++ b/gcc/config/pa/pa.c
@@ -2090,10 +2090,18 @@ hppa_expand_prologue()
 				    size_rtx, tmpreg));
 	else
 	  {
-	    store_reg (1, 0, FRAME_POINTER_REGNUM);
+	    /* It is incorrect to store the saved frame pointer at *sp,
+	       then increment sp (writes beyond the current stack boundary).
+
+	       So instead use stwm to store at *sp and post-increment the
+	       stack pointer as an atomic operation.  Then increment sp to
+	       finish allocating the new frame.  */
+	    emit_insn (gen_post_stwm (stack_pointer_rtx,
+				      stack_pointer_rtx,
+				      GEN_INT (64), tmpreg));
 	    set_reg_plus_d (STACK_POINTER_REGNUM,
 			    STACK_POINTER_REGNUM,
-			    actual_fsize);
+			    actual_fsize - 64);
 	  }
       }
     /* no frame pointer needed.  */