From dad0b8743c79a8772c476cb0f77571db595ef349 Mon Sep 17 00:00:00 2001
From: Andrew Savonichev <andrew.savonichev@gmail.com>
Date: Tue, 11 Nov 2025 09:56:57 +0900
Subject: [PATCH] [LTO] Parse global inline assembly with +all target flags

ModuleSymbolTable extracts symbol names from global inline assembly by
running the target asm parser with a generic CPU and no target flags.

This used to cause problems for top-level inline assembly where
instructions require a target feature. For example, in
global-inline-asm-flags.c we have PACIB and RETAB instructions that
need a +pauth target flag. This test used to fail with a diagnostic:

    <inline asm>:4:1: error: instruction requires: pauth
        4 | pacib     x30, x27
    <inline asm>:5:1: error: instruction requires: pauth
        5 | retab

ModuleSymbolTable does not always have a TargetMachine, so I don't see
how we can get a CPU and target flags that are set in command
line. Instead, the patch changes initialization routine to pass "+all"
target flags, assuming that flags do not change symbols, and we don't
use this asm parser for code generation.
---
 .../CodeGen/AArch64/global-inline-asm-flags.c | 20 +++++++++++++++++++
 llvm/lib/Object/ModuleSymbolTable.cpp         |  3 ++-
 2 files changed, 22 insertions(+), 1 deletion(-)
 create mode 100644 clang/test/CodeGen/AArch64/global-inline-asm-flags.c

diff --git a/clang/test/CodeGen/AArch64/global-inline-asm-flags.c b/clang/test/CodeGen/AArch64/global-inline-asm-flags.c
new file mode 100644
index 0000000000000..0900d0cc44f68
--- /dev/null
+++ b/clang/test/CodeGen/AArch64/global-inline-asm-flags.c
@@ -0,0 +1,20 @@
+// RUN: %clang_cc1 -triple aarch64-linux-gnu -target-feature +pauth -flto=thin -emit-llvm -o - %s | FileCheck %s
+// REQUIRES: aarch64-registered-target
+
+// Check that +pauth target flag is enabled for global inline assembler.
+
+// CHECK: module asm ".text"
+// CHECK: module asm ".balign 16"
+// CHECK: module asm ".globl foo"
+// CHECK: module asm "pacib     x30, x27"
+// CHECK: module asm "retab"
+// CHECK: module asm ".previous"
+
+asm (
+    ".text" "\n"
+    ".balign 16" "\n"
+    ".globl foo\n"
+    "pacib     x30, x27" "\n"
+    "retab" "\n"
+    ".previous" "\n"
+);
diff --git a/llvm/lib/Object/ModuleSymbolTable.cpp b/llvm/lib/Object/ModuleSymbolTable.cpp
index 9442becdb7d33..cf7159a41e714 100644
--- a/llvm/lib/Object/ModuleSymbolTable.cpp
+++ b/llvm/lib/Object/ModuleSymbolTable.cpp
@@ -90,7 +90,8 @@ initializeRecordStreamer(const Module &M,
   if (!MAI)
     return;
 
-  std::unique_ptr<MCSubtargetInfo> STI(T->createMCSubtargetInfo(TT, "", ""));
+  std::unique_ptr<MCSubtargetInfo> STI(
+      T->createMCSubtargetInfo(TT, "", "+all"));
   if (!STI)
     return;