From 79862f24dae69c122381dc0dc1cfd55474b5a75d Mon Sep 17 00:00:00 2001
From: Arnaud Le Blanc <arnaud.lb@gmail.com>
Date: Tue, 28 May 2024 14:20:17 +0200
Subject: [PATCH] Fix TLS access in JIT on FreeBSD/amd64

DTV elements are 8 bytes in size a per ABI [1], and the index is offset by 1
on FreeBSD [2]

[1] http://people.redhat.com/drepper/tls.pdf
[2] https://github.com/freebsd/freebsd-src/blob/bf56e8b9c8639ac4447d223b83cdc128107cc3cd/libexec/rtld-elf/rtld.c#L5260

Closes GH-13928
---
 NEWS                              | 1 +
 ext/opcache/jit/zend_jit_x86.dasc | 9 +++++++++
 2 files changed, 10 insertions(+)

diff --git a/NEWS b/NEWS
index 0d787f184e4de..d7838aa7f4c0c 100644
--- a/NEWS
+++ b/NEWS
@@ -13,6 +13,7 @@ PHP                                                                        NEWS
 - Opcache:
   . Fixed bug GH-14267 (opcache.jit=off does not allow enabling JIT at runtime).
     (ilutov)
+  . Fixed TLS access in JIT on FreeBSD/amd64. (Arnaud)
 
 - Soap:
   . Fixed bug #47925 (PHPClient can't decompress response). (nielsdos)
diff --git a/ext/opcache/jit/zend_jit_x86.dasc b/ext/opcache/jit/zend_jit_x86.dasc
index d083bf47c76d9..7b28b2a767a82 100644
--- a/ext/opcache/jit/zend_jit_x86.dasc
+++ b/ext/opcache/jit/zend_jit_x86.dasc
@@ -2910,6 +2910,15 @@ static int zend_jit_setup(void)
 			: "=a" (ti));
 		tsrm_tls_offset = ti[1];
 		tsrm_tls_index = ti[0] * 8;
+#elif defined(__FreeBSD__)
+		size_t *ti;
+
+		__asm__(
+			"leaq _tsrm_ls_cache@tlsgd(%%rip), %0\n"
+			: "=a" (ti));
+		tsrm_tls_offset = ti[1];
+		/* Index is offset by 1 on FreeBSD (https://github.com/freebsd/freebsd-src/blob/bf56e8b9c8639ac4447d223b83cdc128107cc3cd/libexec/rtld-elf/rtld.c#L5260) */
+		tsrm_tls_index = (ti[0] + 1) * 8;
 #else
 		size_t *ti;