[PATCH v2 03/13] aarch64: Mark x18 register as a fixed register for MS ABI

[Evgeny Karpov <Evgeny.Karpov@microsoft.com>]

From: Zac Walker <zacwalker@microsoft.com>
Date: Fri, 1 Mar 2024 09:56:59 +0100
Subject: [PATCH v2 03/13] aarch64: Mark x18 register as a fixed register for
 MS ABI

Define the MS ABI for aarch64-w64-mingw32.
Adjust FIXED_REGISTERS, CALL_REALLY_USED_REGISTERS and
STATIC_CHAIN_REGNUM for AArch64 MS ABI.
The X18 register is reserved on Windows for the TEB.

gcc/ChangeLog:

	* config.gcc: Define TARGET_AARCH64_MS_ABI when
	AArch64 MS ABI is used.
	* config/aarch64/aarch64-abi-ms.h: New file. Adjust
	FIXED_REGISTERS, CALL_REALLY_USED_REGISTERS and
	STATIC_CHAIN_REGNUM for AArch64 MS ABI.
---
 gcc/config.gcc                      |  1 +
 gcc/config/aarch64/aarch64-abi-ms.h | 64 +++++++++++++++++++++++++++++
 2 files changed, 65 insertions(+)
 create mode 100644 gcc/config/aarch64/aarch64-abi-ms.h

diff --git a/gcc/config.gcc b/gcc/config.gcc
index 2756377e50b..b762393b64c 100644
--- a/gcc/config.gcc
+++ b/gcc/config.gcc
@@ -1265,6 +1265,7 @@ aarch64*-*-linux*)
 	TM_MULTILIB_CONFIG=`echo $TM_MULTILIB_CONFIG | sed 's/^,//'`
 	;;
 aarch64-*-mingw*)
+	tm_file="${tm_file} aarch64/aarch64-abi-ms.h"
 	tmake_file="${tmake_file} aarch64/t-aarch64"
 	case ${enable_threads} in
 	  "" | yes | win32)
diff --git a/gcc/config/aarch64/aarch64-abi-ms.h b/gcc/config/aarch64/aarch64-abi-ms.h
new file mode 100644
index 00000000000..90b0dcc5edf
--- /dev/null
+++ b/gcc/config/aarch64/aarch64-abi-ms.h
@@ -0,0 +1,64 @@
+/* Machine description for AArch64 MS ABI.
+   Copyright (C) 2024 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 3, or (at your option)
+any later version.
+
+GCC is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#ifndef GCC_AARCH64_ABI_MS_H
+#define GCC_AARCH64_ABI_MS_H
+
+/* X18 reserved for the TEB on Windows.  */
+
+#undef FIXED_REGISTERS
+#define FIXED_REGISTERS					\
+  {							\
+    0, 0, 0, 0,   0, 0, 0, 0,	/* R0 - R7.  */		\
+    0, 0, 0, 0,   0, 0, 0, 0,	/* R8 - R15.  */	\
+    0, 0, 1, 0,   0, 0, 0, 0,	/* R16 - R23.  */	\
+    0, 0, 0, 0,   0, 1, 0, 1,	/* R24 - R30, SP.  */	\
+    0, 0, 0, 0,   0, 0, 0, 0,	/* V0 - V7.  */		\
+    0, 0, 0, 0,   0, 0, 0, 0,   /* V8 - V15.  */	\
+    0, 0, 0, 0,   0, 0, 0, 0,   /* V16 - V23.  */	\
+    0, 0, 0, 0,   0, 0, 0, 0,   /* V24 - V31.  */	\
+    1, 1, 1, 1,			/* SFP, AP, CC, VG.  */	\
+    0, 0, 0, 0,   0, 0, 0, 0,	/* P0 - P7.  */		\
+    0, 0, 0, 0,   0, 0, 0, 0,   /* P8 - P15.  */	\
+    1, 1,			/* FFR and FFRT.  */	\
+    1, 1, 1, 1, 1, 1, 1, 1	/* Fake registers.  */	\
+  }
+
+#undef CALL_REALLY_USED_REGISTERS
+#define CALL_REALLY_USED_REGISTERS			\
+  {							\
+    1, 1, 1, 1,   1, 1, 1, 1,	/* R0 - R7.  */		\
+    1, 1, 1, 1,   1, 1, 1, 1,	/* R8 - R15.  */	\
+    1, 1, 0, 0,   0, 0, 0, 0,   /* R16 - R23.  */	\
+    0, 0, 0, 0,   0, 1, 1, 1,	/* R24 - R30, SP.  */	\
+    1, 1, 1, 1,   1, 1, 1, 1,	/* V0 - V7.  */		\
+    0, 0, 0, 0,   0, 0, 0, 0,	/* V8 - V15.  */	\
+    1, 1, 1, 1,   1, 1, 1, 1,   /* V16 - V23.  */	\
+    1, 1, 1, 1,   1, 1, 1, 1,   /* V24 - V31.  */	\
+    1, 1, 1, 0,			/* SFP, AP, CC, VG.  */	\
+    1, 1, 1, 1,   1, 1, 1, 1,	/* P0 - P7.  */		\
+    1, 1, 1, 1,   1, 1, 1, 1,	/* P8 - P15.  */	\
+    1, 1,			/* FFR and FFRT.  */	\
+    0, 0, 0, 0, 0, 0, 0, 0	/* Fake registers.  */	\
+  }
+
+#undef  STATIC_CHAIN_REGNUM
+#define STATIC_CHAIN_REGNUM R17_REGNUM
+
+#endif /* GCC_AARCH64_ABI_MS_H.  */
-- 
2.25.1