From b245143d7c6afa23e341ac69d5377083ccaf0edd Mon Sep 17 00:00:00 2001
From: Dave Cramer <davecramer@gmail.com>
Date: Sun, 13 Jul 2025 06:33:17 -0400
Subject: [PATCH v1 1/2] Address build issues for ARM64 using MSVC

This patch adds support for the ARM64 architecture on Windows 11
and includes work that enables building with MSVC.  This patch also
includes a new intrinsic for spin_delay that is platform specific.
---
 doc/src/sgml/installation.sgml |  2 +-
 meson.build                    | 11 +++++++++--
 src/include/storage/s_lock.h   | 20 ++++++++++++++++++--
 src/port/pg_crc32c_armv8.c     |  2 ++
 src/tools/msvc_gendef.pl       |  8 ++++----
 5 files changed, 34 insertions(+), 9 deletions(-)

diff --git a/doc/src/sgml/installation.sgml b/doc/src/sgml/installation.sgml
index 593202f4fb2..1cddb047a9f 100644
--- a/doc/src/sgml/installation.sgml
+++ b/doc/src/sgml/installation.sgml
@@ -3967,7 +3967,7 @@ configure ... LDFLAGS="-R /usr/sfw/lib:/opt/sfw/lib:/usr/local/lib"
    <sect3 id="install-windows-full-64-bit">
     <title>Special Considerations for 64-Bit Windows</title>
     <para>
-     PostgreSQL will only build for the x64 architecture on 64-bit Windows.
+     PostgreSQL will only build for the x64 and ARM64 architecture on 64-bit Windows.
     </para>
     <para>
      Mixing 32- and 64-bit versions in the same build tree is not supported.
diff --git a/meson.build b/meson.build
index c1e17aa3040..cb572927319 100644
--- a/meson.build
+++ b/meson.build
@@ -1663,7 +1663,7 @@ endif
 zlibopt = get_option('zlib')
 zlib = not_found_dep
 if not zlibopt.disabled()
-  zlib_t = dependency('zlib', required: zlibopt)
+  zlib_t = dependency('zlib', method : 'pkg-config', required: zlibopt)
 
   if zlib_t.type_name() == 'internal'
     # if fallback was used, we don't need to test if headers are present (they
@@ -2494,6 +2494,9 @@ int main(void)
 elif host_cpu == 'arm' or host_cpu == 'aarch64'
 
   prog = '''
+#ifdef _MSC_VER
+#include <intrin.h>
+#else
 #include <arm_acle.h>
 unsigned int crc;
 
@@ -2509,7 +2512,11 @@ int main(void)
 }
 '''
 
-  if cc.links(prog, name: '__crc32cb, __crc32ch, __crc32cw, and __crc32cd without -march=armv8-a+crc',
+  if cc.get_id() == 'msvc'
+    cdata.set('USE_ARMV8_CRC32C', false)
+    cdata.set('USE_ARMV8_CRC32C_WITH_RUNTIME_CHECK', 1)
+    have_optimized_crc = true
+  elif cc.links(prog, name: '__crc32cb, __crc32ch, __crc32cw, and __crc32cd without -march=armv8-a+crc',
       args: test_c_args)
     # Use ARM CRC Extension unconditionally
     cdata.set('USE_ARMV8_CRC32C', 1)
diff --git a/src/include/storage/s_lock.h b/src/include/storage/s_lock.h
index 7f8f566bd40..be7aaf6b013 100644
--- a/src/include/storage/s_lock.h
+++ b/src/include/storage/s_lock.h
@@ -602,15 +602,31 @@ typedef LONG slock_t;
 
 #define SPIN_DELAY() spin_delay()
 
-/* If using Visual C++ on Win64, inline assembly is unavailable.
- * Use a _mm_pause intrinsic instead of rep nop.
+/*
+ * If using Visual C++ on Win64, inline assembly is unavailable.
+ * Use architecture specific intrinsics.
  */
 #if defined(_WIN64)
+/*
+ * For Arm64, use __isb intrinsic. See aarch64 inline assembly definition for details.
+ */
+#ifdef _M_ARM64
+static __forceinline void
+spin_delay(void)
+{
+	 /* Reference: https://learn.microsoft.com/en-us/cpp/intrinsics/arm64-intrinsics#BarrierRestrictions */
+	__isb(_ARM64_BARRIER_SY);
+}
+#else
+/*
+ * For x64, use _mm_pause intrinsic instead of rep nop.
+ */
 static __forceinline void
 spin_delay(void)
 {
 	_mm_pause();
 }
+#endif
 #else
 static __forceinline void
 spin_delay(void)
diff --git a/src/port/pg_crc32c_armv8.c b/src/port/pg_crc32c_armv8.c
index 5ba070bb99d..6a155ddde1e 100644
--- a/src/port/pg_crc32c_armv8.c
+++ b/src/port/pg_crc32c_armv8.c
@@ -14,7 +14,9 @@
  */
 #include "c.h"
 
+#ifndef _MSC_VER
 #include <arm_acle.h>
+#endif
 
 #include "port/pg_crc32c.h"
 
diff --git a/src/tools/msvc_gendef.pl b/src/tools/msvc_gendef.pl
index 868aad51b09..c92c94c4775 100644
--- a/src/tools/msvc_gendef.pl
+++ b/src/tools/msvc_gendef.pl
@@ -118,9 +118,9 @@ sub writedef
 	{
 		my $isdata = $def->{$f} eq 'data';
 
-		# Strip the leading underscore for win32, but not x64
+		# Strip the leading underscore for win32, but not x64 and aarch64
 		$f =~ s/^_//
-		  unless ($arch eq "x86_64");
+		  unless ($arch eq "x86_64" || $arch eq "aarch64");
 
 		# Emit just the name if it's a function symbol, or emit the name
 		# decorated with the DATA option for variables.
@@ -141,7 +141,7 @@ sub writedef
 sub usage
 {
 	die("Usage: msvc_gendef.pl --arch <arch> --deffile <deffile> --tempdir <tempdir> files-or-directories\n"
-		  . "    arch: x86 | x86_64\n"
+		  . "    arch: x86 | x86_64 | aarch64\n"
 		  . "    deffile: path of the generated file\n"
 		  . "    tempdir: directory for temporary files\n"
 		  . "    files or directories: object files or directory containing object files\n"
@@ -158,7 +158,7 @@ GetOptions(
 	'tempdir:s' => \$tempdir,) or usage();
 
 usage("arch: $arch")
-  unless ($arch eq 'x86' || $arch eq 'x86_64');
+  unless ($arch eq 'x86' || $arch eq 'x86_64' || $arch eq 'aarch64');
 
 my @files;
 
-- 
2.52.0.windows.1