From: Eric Botcazou <ebotcazou@adacore.com>
Date: Wed, 15 Feb 2023 22:32:12 +0000 (+0100)
Subject: Fix PR target/90458
X-Git-Tag: releases/gcc-12.3.0~339
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=25b80834e2ce6725e676ef33fbf0d009b3173955;p=thirdparty%2Fgcc.git

Fix PR target/90458

This is the incompatibility of -fstack-clash-protection with Windows SEH.
Now the Windows ports always enable TARGET_STACK_PROBE, which means that
the stack is always probed (out of line) so -fstack-clash-protection does
nothing more.

gcc/
	PR target/90458
	* config/i386/i386.cc (ix86_compute_frame_layout): Disable the
	effects of -fstack-clash-protection for TARGET_STACK_PROBE.
	(ix86_expand_prologue): Likewise.
---

diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
index 962f8c82b48a..669b1efdb62c 100644
--- a/gcc/config/i386/i386.cc
+++ b/gcc/config/i386/i386.cc
@@ -6818,7 +6818,9 @@ ix86_compute_frame_layout (void)
 	 stack clash protections are enabled and the allocated frame is
 	 larger than the probe interval, then use pushes to save
 	 callee saved registers.  */
-      || (flag_stack_clash_protection && to_allocate > get_probe_interval ()))
+      || (flag_stack_clash_protection
+	  && !ix86_target_stack_probe ()
+	  && to_allocate > get_probe_interval ()))
     frame->save_regs_using_mov = false;
 
   if (ix86_using_red_zone ()
@@ -8703,8 +8705,11 @@ ix86_expand_prologue (void)
       sse_registers_saved = true;
     }
 
-  /* If stack clash protection is requested, then probe the stack.  */
-  if (allocate >= 0 && flag_stack_clash_protection)
+  /* If stack clash protection is requested, then probe the stack, unless it
+     is already probed on the target.  */
+  if (allocate >= 0
+      && flag_stack_clash_protection
+      && !ix86_target_stack_probe ())
     {
       ix86_adjust_stack_and_probe (allocate, int_registers_saved, false);
       allocate = 0;