From: Eric Botcazou <ebotcazou@adacore.com>
Date: Wed, 3 Mar 2021 11:25:03 +0000 (+0100)
Subject: Fix ICE with pathologically large frames
X-Git-Tag: releases/gcc-10.3.0~255
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2939b358936bb824330888def98ad848dea41483;p=thirdparty%2Fgcc.git

Fix ICE with pathologically large frames

gcc/
	PR target/99234
	* config/i386/i386.c (ix86_compute_frame_layout): For a SEH target,
	point back the hard frame pointer to its default location when the
	frame is larger than SEH_MAX_FRAME_SIZE.
---

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 7b8036613664..e23f92b58cc0 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -6357,7 +6357,8 @@ ix86_compute_frame_layout (void)
       frame->hard_frame_pointer_offset = frame->sse_reg_save_offset;
 
       /* If we can leave the frame pointer where it is, do so.  Also, return
-	 the establisher frame for __builtin_frame_address (0).  */
+	 the establisher frame for __builtin_frame_address (0) or else if the
+	 frame overflows the SEH maximum frame size.  */
       const HOST_WIDE_INT diff
 	= frame->stack_pointer_offset - frame->hard_frame_pointer_offset;
       if (diff <= 255)
@@ -6375,6 +6376,8 @@ ix86_compute_frame_layout (void)
 	     frame that is addressable with 8-bit offsets.  */
 	  frame->hard_frame_pointer_offset = frame->stack_pointer_offset - 128;
 	}
+      else
+	frame->hard_frame_pointer_offset = frame->hfp_save_offset;
     }
 }