From 9c83c3d3f443eb92f87dc87c7dcfe95577b95621 Mon Sep 17 00:00:00 2001
From: Simon South <simon@simonsouth.net>
Date: Thu, 28 May 2020 14:29:55 -0400
Subject: [PATCH] Add support for aarch64 on GNU/Linux

---
 configure.ac                      |  10 +-
 src/arch/Makefile.am              |   2 +-
 src/arch/aarch64.h                | 110 ++++++++++++++++
 src/os/linux/Makefile.am          |   2 +-
 src/os/linux/aarch64/Makefile.am  |  28 ++++
 src/os/linux/aarch64/callNative.S | 212 ++++++++++++++++++++++++++++++
 src/os/linux/aarch64/dll_md.c     |  59 +++++++++
 src/os/linux/aarch64/init.c       |  51 +++++++
 8 files changed, 469 insertions(+), 5 deletions(-)
 create mode 100644 src/arch/aarch64.h
 create mode 100644 src/os/linux/aarch64/Makefile.am
 create mode 100644 src/os/linux/aarch64/callNative.S
 create mode 100644 src/os/linux/aarch64/dll_md.c
 create mode 100644 src/os/linux/aarch64/init.c

diff --git a/configure.ac b/configure.ac
index ccd530f..707f281 100644
--- a/configure.ac
+++ b/configure.ac
@@ -43,6 +43,7 @@ amd64-*-freebsd*) host_os=bsd libdl_needed=no ;;
 arm*-*-linux*) host_cpu=arm host_os=linux ;;
 arm*-*-openbsd*) host_cpu=arm host_os=bsd libdl_needed=no ;;
 arm*-*-freebsd*) host_cpu=arm host_os=bsd libdl_needed=no ;;
+aarch64*-*-linux*) host_cpu=aarch64 host_os=linux ;;
 powerpc*-*-linux*) host_cpu=powerpc host_os=linux ;;
 powerpc*-*-openbsd*) host_cpu=powerpc host_os=bsd libdl_needed=no ;;
 powerpc*-*-freebsd*) host_cpu=powerpc host_os=bsd libdl_needed=no ;;
@@ -149,9 +150,11 @@ AC_ARG_ENABLE(runtime-reloc-checks,
 
 AC_ARG_ENABLE(int-inlining,
     [AS_HELP_STRING(--enable-int-inlining,enable inline threaded version of the interpreter
-                   (by default enabled on x86_64, i386 and powerpc, disabled otherwise))],,
-    [if test "$host_cpu" = x86_64 -o "$host_cpu" = i386 -o "$host_cpu" = powerpc && \
-        test "$cross_compiling" = no -o "$enable_runtime_reloc_checks" != no; then
+                   (by default enabled on x86_64, i386, powerpc and aarch64,
+                   disabled otherwise))],,
+    [if test "$host_cpu" = x86_64 -o "$host_cpu" = i386 -o "$host_cpu" = powerpc -o \
+             "$host_cpu" = aarch64 && test "$cross_compiling" = no -o \
+             "$enable_runtime_reloc_checks" != no; then
          enable_int_inlining=yes
        else
          enable_int_inlining=no
@@ -298,6 +301,7 @@ AC_CONFIG_FILES(
     src/os/linux/x86_64/Makefile \
     src/os/linux/parisc/Makefile \
     src/os/linux/mips/Makefile \
+    src/os/linux/aarch64/Makefile \
     src/os/darwin/i386/Makefile \
     src/os/darwin/arm/Makefile \
     src/os/darwin/powerpc/Makefile \
diff --git a/src/arch/Makefile.am b/src/arch/Makefile.am
index 078c1de..afb26d1 100644
--- a/src/arch/Makefile.am
+++ b/src/arch/Makefile.am
@@ -19,4 +19,4 @@
 ## Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 ##
 
-EXTRA_DIST = powerpc.h arm.h i386.h x86_64.h parisc.h mips.h
+EXTRA_DIST = powerpc.h arm.h i386.h x86_64.h parisc.h mips.h aarch64.h
diff --git a/src/arch/aarch64.h b/src/arch/aarch64.h
new file mode 100644
index 0000000..c96aa9f
--- /dev/null
+++ b/src/arch/aarch64.h
@@ -0,0 +1,110 @@
+/*
+ * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008
+ * Robert Lougher <rob@lougher.org.uk>.
+ * Copyright (C) 2020 Simon South <simon@simonsouth.net>.
+ *
+ * This file is part of JamVM.
+ *
+ * This program 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 2,
+ * or (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include <stdint.h>
+
+#define OS_ARCH "aarch64"
+
+#define HANDLER_TABLE_T static const void
+#define DOUBLE_1_BITS 0x3ff0000000000000LL
+
+#define READ_DBL(v,p,l) v = ((u8)p[0]<<56)|((u8)p[1]<<48)|((u8)p[2]<<40) \
+                            |((u8)p[3]<<32)|((u8)p[4]<<24)|((u8)p[5]<<16) \
+                            |((u8)p[6]<<8)|(u8)p[7]; p+=8
+
+/* Needed for i386 -- empty here */
+#define FPU_HACK
+
+#define COMPARE_AND_SWAP_64(addr, old_val, new_val)             \
+({                                                              \
+    int result, read_val;                                       \
+    __asm__ __volatile__ ("                                     \
+        1:      ldaxr %2, %1;                                   \
+                cmp %2, %3;                                     \
+                b.ne 2f;                                        \
+                stlxr %w0, %4, %1;                              \
+                cmp %w0, wzr;                                   \
+                b.ne 1b;                                        \
+        2:      cset %w0, eq;"                                  \
+    : "=&r" (result), "+Q" (*addr), "=&r" (read_val)            \
+    : "r" (old_val), "r" (new_val)                              \
+    : "cc");                                                    \
+    result;                                                     \
+})
+
+#define COMPARE_AND_SWAP(addr, old_val, new_val)                \
+        COMPARE_AND_SWAP_64(addr, old_val, new_val)
+
+#define LOCKWORD_READ(addr)                                     \
+({                                                              \
+    uintptr_t result;                                           \
+    __asm__ __volatile__ ("                                     \
+                ldar %0, %1;"                                   \
+    : "=r" (result)                                             \
+    : "Q" (*addr)                                               \
+    : "cc");                                                    \
+    result;                                                     \
+})
+
+#define LOCKWORD_WRITE(addr, value)                             \
+({                                                              \
+    __asm__ __volatile__ ("                                     \
+                stlr %1, %0;"                                   \
+    : "=Q" (*addr)                                              \
+    : "r" (value)                                               \
+    : "cc");                                                    \
+})
+
+#define LOCKWORD_COMPARE_AND_SWAP(addr, old_val, new_val)       \
+        COMPARE_AND_SWAP_64(addr, old_val, new_val)
+
+#define FLUSH_CACHE(addr, length)                               \
+{                                                               \
+    uintptr_t start = (uintptr_t) (addr);                       \
+    uintptr_t end = start + length;                             \
+    uintptr_t i;                                                \
+                                                                \
+    for(i = start & aarch64_data_cache_line_mask;               \
+        i < end;                                                \
+        i += aarch64_data_cache_line_len)                       \
+        __asm__ ("dc cvau, %0" :: "r" (i));                     \
+                                                                \
+    __asm__ ("dsb ish");                                        \
+                                                                \
+    for(i = start & aarch64_instruction_cache_line_mask;        \
+        i < end;                                                \
+        i += aarch64_instruction_cache_line_len)                \
+        __asm__ ("ic ivau, %0" :: "r" (i));                     \
+                                                                \
+    __asm__ ("dsb ish; isb");                                   \
+}
+
+#define MBARRIER() __asm__ ("dmb ish" ::: "memory")
+#define UNLOCK_MBARRIER() __asm__ ("dmb ish" ::: "memory")
+#define JMM_LOCK_MBARRIER() __asm__ ("dmb ish" ::: "memory")
+#define JMM_UNLOCK_MBARRIER() JMM_LOCK_MBARRIER()
+
+/* Defined in src/os/linux/aarch64/init.c */
+extern unsigned char aarch64_data_cache_line_len;
+extern uintptr_t aarch64_data_cache_line_mask;
+extern unsigned char aarch64_instruction_cache_line_len;
+extern uintptr_t aarch64_instruction_cache_line_mask;
diff --git a/src/os/linux/Makefile.am b/src/os/linux/Makefile.am
index aa29be1..d582b97 100644
--- a/src/os/linux/Makefile.am
+++ b/src/os/linux/Makefile.am
@@ -20,7 +20,7 @@
 ##
 
 SUBDIRS = @arch@
-DIST_SUBDIRS = powerpc arm i386 x86_64 parisc mips
+DIST_SUBDIRS = powerpc arm i386 x86_64 parisc mips aarch64
 
 noinst_LTLIBRARIES = libos.la
 libos_la_SOURCES = os.c
diff --git a/src/os/linux/aarch64/Makefile.am b/src/os/linux/aarch64/Makefile.am
new file mode 100644
index 0000000..1024c3a
--- /dev/null
+++ b/src/os/linux/aarch64/Makefile.am
@@ -0,0 +1,28 @@
+##
+## Copyright (C) 2003, 2004, 2005, 2006, 2007, 2010, 2011, 2012
+## Robert Lougher <rob@lougher.org.uk>.
+##
+## File added by Simon South <simon@simonsouth.net>.
+##
+## This file is part of JamVM.
+##
+## This program 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 2,
+## or (at your option) any later version.
+##
+## This program 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 this program; if not, write to the Free Software
+## Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+##
+
+noinst_LTLIBRARIES = libnative.la
+libnative_la_SOURCES = init.c dll_md.c callNative.S
+
+AM_CPPFLAGS = -I$(top_builddir)/src -I$(top_srcdir)/src
+AM_CCASFLAGS = -I$(top_builddir)/src
diff --git a/src/os/linux/aarch64/callNative.S b/src/os/linux/aarch64/callNative.S
new file mode 100644
index 0000000..e067c4f
--- /dev/null
+++ b/src/os/linux/aarch64/callNative.S
@@ -0,0 +1,212 @@
+/*
+ * Copyright (C) 2008, 2009, 2011, 2012 Robert Lougher <rob@jamvm.org.uk>.
+ * Copyright (C) 2020 Simon South <simon@simonsouth.net>.
+ *
+ * This file is part of JamVM.
+ *
+ * This program 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 2,
+ * or (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include "config.h"
+
+#ifndef USE_FFI
+        .text
+        .arch armv8-a
+        .align 2
+        .global callJNIMethod
+        .type callJNIMethod,function
+
+/*
+ * Arguments passed in:
+ *
+ * x0 JNIEnv
+ * x1 class or NULL
+ * x2 sig
+ * w3 extra arg
+ * x4 ostack
+ * x5 function pntr
+ * w6 args count
+ */
+
+/* Register usage:
+ *
+ * x20 ostack
+ * x19 sig pntr
+ * x16 function pntr
+ * x15 ostack pntr
+ * x14 args pntr
+ * x13 float/double handler
+ * x12 int/long handler
+ * w11 fp regs remaining
+ * w10 int regs remaining
+ * x9 scratch
+ * x2-x7 outgoing int args
+ * x1 outgoing class or this pntr
+ * x0 outgoing JNIEnv (as passed in)
+ *
+ * d0 - d7 outgoing float args
+ */
+
+callJNIMethod:
+        stp     x29, x30, [sp, #-32]!
+        mov     x29, sp
+        stp     x19, x20, [x29, #16]
+
+        sub     sp, sp, w3              /* allocate room for stacked args */
+        mov     x14, sp
+
+        mov     x20, x4                 /* preserve ostack */
+        add     x19, x2, #1             /* init sig pntr -- skipping '(' */
+
+        mov     x16, x5                 /* save function pntr */
+        mov     x15, x20                /* init ostack pntr */
+
+        adr     x13, fp_reg_handlers-8
+        adr     x12, int_reg_handlers-8
+
+        mov     w11, #8                 /* fp regs remaining */
+        mov     w10, #6                 /* int regs remaining */
+
+        cbnz    x1, scan_sig            /* is method non-static? */
+        ldr     x1, [x15], #8           /* yes, load x1 with "this" */
+
+scan_sig:
+        ldrb    w9, [x19], #1           /* get next sig char */
+
+        cmp     w9, #41                 /* ')' */
+        b.eq    done
+
+        cmp     w9, #74                 /* 'J' */
+        b.eq    long
+
+        cmp     w9, #70                 /* 'F' */
+        b.eq    float
+
+        cmp     w9, #68                 /* 'D' */
+        b.eq    double
+
+skip_brackets:
+        cmp     w9, #91                 /* '[' */
+        b.ne    1f
+        ldrb    w9, [x19], #1
+        b       skip_brackets
+1:
+        cmp     w9, #76                 /* 'L' */
+        b.ne    int
+
+skip_ref:
+        ldrb    w9, [x19], #1
+        cmp     w9, #59                 /* ';' */
+        b.ne    skip_ref
+
+int:
+        ldr     x9, [x15], #8
+        cbz     w10, stack_push
+
+load_int_reg:
+        sub     w10, w10, #1
+        add     x12, x12, #8
+        br      x12
+
+int_reg_handlers:
+        mov     x2, x9
+        b       scan_sig
+        mov     x3, x9
+        b       scan_sig
+        mov     x4, x9
+        b       scan_sig
+        mov     x5, x9
+        b       scan_sig
+        mov     x6, x9
+        b       scan_sig
+        mov     x7, x9
+        b       scan_sig
+
+long:
+        ldr     x9, [x15], #16
+        cbz     w10, stack_push
+        b       load_int_reg
+
+float:
+        ldr     w9, [x15], #8
+        cbz     w11, stack_push
+        b       load_fp_reg
+
+double:
+        ldr     x9, [x15], #16
+        cbz     w11, stack_push
+
+load_fp_reg:
+        sub     w11, w11, #1
+        add     x13, x13, #8
+        br      x13
+
+fp_reg_handlers:
+        fmov    d0, x9
+        b       scan_sig
+        fmov    d1, x9
+        b       scan_sig
+        fmov    d2, x9
+        b       scan_sig
+        fmov    d3, x9
+        b       scan_sig
+        fmov    d4, x9
+        b       scan_sig
+        fmov    d5, x9
+        b       scan_sig
+        fmov    d6, x9
+        b       scan_sig
+        fmov    d7, x9
+        b       scan_sig
+
+stack_push:
+        str     x9, [x14], #8
+        b       scan_sig
+
+done:
+        /* Call the function */
+        blr     x16
+
+        mov     sp, x29                 /* Pop argument area */
+
+        ldrb    w9, [x19]               /* Return type */
+
+        cmp     w9, #86                 /* 'V' */
+        b.eq    return
+
+        cmp     w9, #68                 /* 'D' */
+        b.ne    2f
+        str     d0, [x20], #16
+        b       return
+2:
+        cmp     w9, #70                 /* 'F' */
+        b.ne    3f
+        str     s0, [x20], #8
+        b       return
+3:
+        cmp     w9, #74                 /* 'J' */
+        b.ne    4f
+        str     x0, [x20], #16
+        b       return
+4:
+        str     x0, [x20], #8
+
+return:
+        mov     x0, x20                 /* return ostack */
+
+        ldp     x19, x20, [x29, #16]
+        ldp     x29, x30, [sp], #32
+        ret
+#endif
diff --git a/src/os/linux/aarch64/dll_md.c b/src/os/linux/aarch64/dll_md.c
new file mode 100644
index 0000000..189f8a8
--- /dev/null
+++ b/src/os/linux/aarch64/dll_md.c
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2010, 2011
+ * Robert Lougher <rob@jamvm.org.uk>.
+ * Copyright (C) 2020 Simon South <simon@simonsouth.net>.
+ *
+ * This file is part of JamVM.
+ *
+ * This program 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 2,
+ * or (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include "jam.h"
+
+#ifndef USE_FFI
+
+int nativeExtraArg(MethodBlock *mb) {
+    char *sig = mb->type;
+    int stack_args = 0;
+    int int_args = 6;
+    int fp_args = 8;
+
+    while(*++sig != ')')
+        switch(*sig) {
+        case 'F':
+        case 'D':
+            if(fp_args == 0)
+                stack_args += 8;
+            else
+                fp_args--;
+
+        default:
+            if(int_args == 0)
+                stack_args += 8;
+            else
+                int_args--;
+
+            if(*sig == '[')
+                while(*++sig == '[');
+            if(*sig == 'L')
+                while(*++sig != ';');
+            break;
+        }
+
+    /* Ensure the stack remains 16 byte aligned. */
+    return (stack_args + 15) & ~15;
+}
+
+#endif
diff --git a/src/os/linux/aarch64/init.c b/src/os/linux/aarch64/init.c
new file mode 100644
index 0000000..e03b446
--- /dev/null
+++ b/src/os/linux/aarch64/init.c
@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2003, 2004, 2005, 2006, 2007
+ * Robert Lougher <rob@lougher.org.uk>.
+ * Copyright (C) 2020 Simon South <simon@simonsouth.net>.
+ *
+ * This file is part of JamVM.
+ *
+ * This program 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 2,
+ * or (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include "arch/aarch64.h"
+
+/* Length in bytes of the smallest line in the host system's data cache */
+unsigned char aarch64_data_cache_line_len;
+
+/* Mask used to align a virtual address to a line in the data cache */
+uintptr_t aarch64_data_cache_line_mask;
+
+/* Length in bytes of the smallest line in the host system's instruction
+   cache */
+unsigned char aarch64_instruction_cache_line_len;
+
+/* Mask used to align a virtual address to a line in the instruction cache */
+uintptr_t aarch64_instruction_cache_line_mask;
+
+void initialisePlatform() {
+    unsigned int cache_type;
+
+    /* Extract information from the cache-type register, which describes aspects
+       of the host's cache configuration */
+    __asm__ ("mrs %0, ctr_el0" : "=r" (cache_type));
+
+    aarch64_data_cache_line_len = 4 << ((cache_type >> 16) & 0x0f);
+    aarch64_data_cache_line_mask = ~(aarch64_data_cache_line_len - 1);
+
+    aarch64_instruction_cache_line_len = 4 << (cache_type & 0x0f);
+    aarch64_instruction_cache_line_mask =
+        ~(aarch64_instruction_cache_line_len - 1);
+}
-- 
2.26.2

