From 2e5f3d9f0596e60031d7c56cf943cf00e81fe53d Mon Sep 17 00:00:00 2001
From: zhaozhou <zhaozhou@loongson.cn>
Date: Thu, 16 Apr 2026 17:31:41 +0800
Subject: [PATCH] LoongArch: Enforce 4-byte align for machine instructions

If no alignment is specified in the assembly file, LoongArch will not
perform forced alignment. When this object file (.o) is linked into an
executable, instructions may not be 4-byte aligned, which will
eventually cause instruction fetch errors.

For example, the above issue can occur when generating a shared object
file (.so) with the -nostdlib option.
---
 gas/config/tc-loongarch.c                  | 5 +++++
 gas/testsuite/gas/loongarch/insn_align_4.d | 7 +++++++
 gas/testsuite/gas/loongarch/insn_align_4.s | 4 ++++
 3 files changed, 16 insertions(+)
 create mode 100644 gas/testsuite/gas/loongarch/insn_align_4.d
 create mode 100644 gas/testsuite/gas/loongarch/insn_align_4.s

diff --git a/gas/config/tc-loongarch.c b/gas/config/tc-loongarch.c
index 1eb35f2c75e..d067318ce24 100644
--- a/gas/config/tc-loongarch.c
+++ b/gas/config/tc-loongarch.c
@@ -1432,6 +1432,11 @@ loongarch_assemble_INSNs (char *str, unsigned int expand_from_macro)
       if (*str == '\0')
 	break;
 
+      /* LoongArch instructions require 4-byte alignment.  When emitting
+	 instructions into any section, record the appropriate section
+	 alignment.  */
+      record_alignment (now_seg, 2);
+
       struct loongarch_cl_insn the_one;
       memset (&the_one, 0, sizeof (the_one));
       the_one.name = str;
diff --git a/gas/testsuite/gas/loongarch/insn_align_4.d b/gas/testsuite/gas/loongarch/insn_align_4.d
new file mode 100644
index 00000000000..31a5d352a76
--- /dev/null
+++ b/gas/testsuite/gas/loongarch/insn_align_4.d
@@ -0,0 +1,7 @@
+#as:
+#readelf: -S
+
+#...
+  \[ [0-9]+\] \.text             PROGBITS         [0-9a-f]{16}  [0-9a-f]{8}
+       [0-9a-f]{16}  [0-9a-f]{16}  AX       0     0     4
+#...
diff --git a/gas/testsuite/gas/loongarch/insn_align_4.s b/gas/testsuite/gas/loongarch/insn_align_4.s
new file mode 100644
index 00000000000..7b4922c113f
--- /dev/null
+++ b/gas/testsuite/gas/loongarch/insn_align_4.s
@@ -0,0 +1,4 @@
+.type test, @function
+test:
+  jirl	$ra, $ra, 0
+.size test, .-test