From a5dd99f7ef4fa5f9542851431bdd149a22b87fd2 Mon Sep 17 00:00:00 2001
From: Eric Botcazou <ebotcazou@adacore.com>
Date: Wed, 15 Feb 2023 23:32:12 +0100
Subject: [PATCH] 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.
---
gcc/config/i386/i386.cc | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
index 3cacf738c4ae..22f444be23c8 100644
--- a/gcc/config/i386/i386.cc
+++ b/gcc/config/i386/i386.cc
@@ -6876,7 +6876,9 @@ 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 ()
@@ -8761,8 +8763,11 @@ 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;
--
GitLab