[clang] [clang][Driver] Pass -machine argument to the linker explicitly for ARM64EC targets. (PR #86835)

[Jacek Caban via cfe-commits]

https://github.com/cjacek updated https://github.com/llvm/llvm-project/pull/86835

>From 7a4a69076b2172e50ce305f97e0f97f67d00aa32 Mon Sep 17 00:00:00 2001
From: Jacek Caban <jacek at codeweavers.com>
Date: Thu, 28 Mar 2024 14:58:48 +0100
Subject: [PATCH] [clang][Driver] Pass -machine argument to the linker
 explicitly for ARM64EC targets.

---
 clang/include/clang/Driver/Options.td |  3 +++
 clang/lib/Driver/ToolChains/MSVC.cpp  |  8 ++++++++
 clang/test/Driver/msvc-link.c         | 20 ++++++++++++++++++++
 3 files changed, 31 insertions(+)

diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index 29066ea14280c2..39c932e72fdefd 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -4507,6 +4507,9 @@ def mwindows : Joined<["-"], "mwindows">, Group<m_Group>;
 def mdll : Joined<["-"], "mdll">, Group<m_Group>;
 def municode : Joined<["-"], "municode">, Group<m_Group>;
 def mthreads : Joined<["-"], "mthreads">, Group<m_Group>;
+def marm64x : Joined<["-"], "marm64x">, Group<m_Group>,
+  Visibility<[ClangOption, CLOption]>,
+  HelpText<"Link as a hybrid ARM64X image">;
 def mguard_EQ : Joined<["-"], "mguard=">, Group<m_Group>,
   HelpText<"Enable or disable Control Flow Guard checks and guard tables emission">,
   Values<"none,cf,cf-nochecks">;
diff --git a/clang/lib/Driver/ToolChains/MSVC.cpp b/clang/lib/Driver/ToolChains/MSVC.cpp
index dc534a33e6d0ef..fbf2f45b543844 100644
--- a/clang/lib/Driver/ToolChains/MSVC.cpp
+++ b/clang/lib/Driver/ToolChains/MSVC.cpp
@@ -79,6 +79,11 @@ void visualstudio::Linker::ConstructJob(Compilation &C, const JobAction &JA,
     CmdArgs.push_back(
         Args.MakeArgString(std::string("-out:") + Output.getFilename()));
 
+  if (Args.hasArg(options::OPT_marm64x))
+    CmdArgs.push_back("-machine:arm64x");
+  else if (TC.getTriple().isWindowsArm64EC())
+    CmdArgs.push_back("-machine:arm64ec");
+
   if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles) &&
       !C.getDriver().IsCLMode() && !C.getDriver().IsFlangMode()) {
     CmdArgs.push_back("-defaultlib:libcmt");
@@ -1017,4 +1022,7 @@ void MSVCToolChain::addClangTargetOptions(
   if (DriverArgs.hasFlag(options::OPT_fno_rtti, options::OPT_frtti,
                          /*Default=*/false))
     CC1Args.push_back("-D_HAS_STATIC_RTTI=0");
+
+  if (Arg *A = DriverArgs.getLastArgNoClaim(options::OPT_marm64x))
+    A->ignoreTargetSpecific();
 }
diff --git a/clang/test/Driver/msvc-link.c b/clang/test/Driver/msvc-link.c
index 64e099ea63042f..f80b043c6cfce2 100644
--- a/clang/test/Driver/msvc-link.c
+++ b/clang/test/Driver/msvc-link.c
@@ -36,3 +36,23 @@
 // VFSOVERLAY: "--vfsoverlay"
 // VFSOVERLAY: lld-link
 // VFSOVERLAY: "/vfsoverlay:{{.*}}" "{{.*}}.obj"
+
+// RUN: %clang -target arm64ec-pc-windows-msvc -fuse-ld=link -### %s 2>&1 | FileCheck --check-prefix=ARM64EC %s
+// RUN: %clang_cl -target arm64ec-pc-windows-msvc -fuse-ld=link -### %s 2>&1 | FileCheck --check-prefix=ARM64EC %s
+// RUN: %clang_cl -arm64EC -fuse-ld=link -### %s 2>&1 | FileCheck --check-prefix=ARM64EC %s
+// ARM64EC: "-machine:arm64ec"
+
+// RUN: %clang -target arm64ec-pc-windows-msvc -fuse-ld=link -marm64x -### %s 2>&1 | \
+// RUN:        FileCheck --check-prefix=ARM64X %s
+// RUN: %clang -target aarch64-pc-windows-msvc -fuse-ld=link -marm64x -### %s 2>&1 | \
+// RUN:        FileCheck --check-prefix=ARM64X %s
+// RUN: %clang_cl -marm64x -fuse-ld=link -### %s 2>&1 | FileCheck --check-prefix=ARM64X %s
+// RUN: %clang_cl -arm64EC -marm64x -fuse-ld=link -### %s 2>&1 | FileCheck --check-prefix=ARM64X %s
+// ARM64X: "-machine:arm64x"
+
+// RUN: not %clang -target x86_64-linux-gnu -marm64x -### %s 2>&1 | FileCheck --check-prefix=HYBRID-ERR %s
+// HYBRID-ERR: error: unsupported option '-marm64x' for target 'x86_64-linux-gnu'
+
+// RUN: %clang -c -marm64x  -target arm64ec-pc-windows-msvc -fuse-ld=link -### %s 2>&1 | \
+// RUN:        FileCheck --check-prefix=HYBRID-WARN %s
+// HYBRID-WARN: warning: argument unused during compilation: '-marm64x' [-Wunused-command-line-argument]