From ca11b53896365c948426974cb90e8f71c70d123b Mon Sep 17 00:00:00 2001
From: Simon South <simon@simonsouth.net>
Date: Sun, 31 May 2020 20:36:43 -0400
Subject: [PATCH] Guard floating-point opcodes with explicit memory barrier

---
 src/interp/engine/interp-inlining.h | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/interp/engine/interp-inlining.h b/src/interp/engine/interp-inlining.h
index 3339b0e..4ee5c5a 100644
--- a/src/interp/engine/interp-inlining.h
+++ b/src/interp/engine/interp-inlining.h
@@ -78,8 +78,17 @@
    4.3, we need to insert a label, and ensure its address
    is taken (to stop it being optimised out).  However,
    this reduces performance on PowerPC by approx 1 - 2%.
+
+   With gcc 5 and newer an asm statement with a "memory"
+   clobber argument explicitly sets a memory barrier for the
+   compiler, preventing it from reordering memory accesses
+   in a way that breaks decaching.
 */
-#if (__GNUC__ == 4) && (__GNUC_MINOR__ >= 3)
+#if (__GNUC__ > 4)
+#define DEF_GUARD_TABLE(level) /* none */
+#define GUARD(opcode, level)   __asm__("" ::: "memory");
+#define GUARD_TBLS             /* none */
+#elif (__GNUC__ == 4) && (__GNUC_MINOR__ >= 3)
 #define DEF_GUARD_TABLE(level) DEF_HANDLER_TABLE(level, GUARD)
 #define GUARD(opcode, level)   label(opcode, level, GUARD)
 #define GUARD_TBLS             , HNDLR_TBLS(GUARD)
-- 
2.26.2

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<tr><td><span title='2021-10-08 12:08:43 +0200'>2021-10-08</span></td><td><a href='/guix/commit/gnu/packages/search.scm?id=f45f482e9bf3cb9b3413ca800aa596c0b422364e'>gnu: plocate: Update to 1.1.12.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/search.scm (plocate): Update to 1.1.12.
</span></span></td><td>Nicolas Goaziou</td></tr>
<tr><td><span title='2021-10-08 12:07:35 +0200'>2021-10-08</span></td><td><a href='/guix/commit/gnu/packages/search.scm?id=55092b49803477b9ae0cd89ab01ce3275cf75d0e'>gnu: Add plocate.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/search.scm (plocate): New variable.

Add the required imports from (guix build-system meson) and
(gnu packages pkg-config).

Signed-off-by: Nicolas Goaziou &lt;mail@nicolasgoaziou.fr&gt;
</span></span></td><td>Alexandr Vityazev</td></tr>
<tr><td><span title='2021-07-19 19:57:52 +0200'>2021-07-19</span></td><td><a href='/guix/commit/gnu/packages/search.scm?id=52058a1144522ca6b552e565b50dce503671d37a'>gnu: Add searx.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/search.scm (searx): New variable.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Vinicius Monego</td></tr>
<tr><td><span title='2021-04-27 15:54:00 +0200'>2021-04-27</span></td><td><a href='/guix/commit/gnu/packages/search.scm?id=19f67a9197c41892e8e37020816a4f7f337d7e8d'>gnu: ugrep: Use GIT-FILE-NAME helper.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/search.scm (ugrep)[source]: Use GIT-FILE-NAME.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2021-04-27 15:54:00 +0200'>2021-04-27</span></td><td><a href='/guix/commit/gnu/packages/search.scm?id=4206cf1fa89deb0f30b7b5e3147b059a9908db6a'>gnu: ugrep: Update to 3.1.12.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/search.scm (ugrep): Update to 3.1.12.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2021-04-04 15:16:45 +0200'>2021-04-04</span></td><td><a href='/guix/commit/gnu/packages/search.scm?id=aaec5de3a7bcef35421bc801e0f747daa8dbfb5c'>gnu: ugrep: Update to 3.1.11.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/search.scm (ugrep): Update to 3.1.11.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>