[PATCH 08/16] lib: Linux riscv64-mes-gcc support.

[W. J. van der Laan]

* lib/linux/riscv64-mes-gcc/_exit.c: Added to make it possible to
compile mes for riscv64-mes-gcc.
* lib/linux/riscv64-mes-gcc/_write.c: Same.
* lib/linux/riscv64-mes-gcc/crt1.c: Same.
* lib/linux/riscv64-mes-gcc/syscall-internal.c: Same.
* lib/linux/riscv64-mes-gcc/syscall.c: Same.
---
 lib/linux/riscv64-mes-gcc/_exit.c            |  38 +++++
 lib/linux/riscv64-mes-gcc/_write.c           |  40 +++++
 lib/linux/riscv64-mes-gcc/crt1.c             |  90 ++++++++++
 lib/linux/riscv64-mes-gcc/syscall-internal.c |  62 +++++++
 lib/linux/riscv64-mes-gcc/syscall.c          | 166 +++++++++++++++++++
 5 files changed, 396 insertions(+)
 create mode 100644 lib/linux/riscv64-mes-gcc/_exit.c
 create mode 100644 lib/linux/riscv64-mes-gcc/_write.c
 create mode 100644 lib/linux/riscv64-mes-gcc/crt1.c
 create mode 100644 lib/linux/riscv64-mes-gcc/syscall-internal.c
 create mode 100644 lib/linux/riscv64-mes-gcc/syscall.c

diff --git a/lib/linux/riscv64-mes-gcc/_exit.c 
b/lib/linux/riscv64-mes-gcc/_exit.c
new file mode 100644
index 
0000000000000000000000000000000000000000..2e622bcf1a292fb21a6fc5e26050b3c30875c124
--- /dev/null
+++ b/lib/linux/riscv64-mes-gcc/_exit.c
@@ -0,0 +1,38 @@
+/* -*-comment-start: "//";comment-end:""-*-
+ * GNU Mes --- Maxwell Equations of Software
+ * Copyright © 2016,2017,2019,2020 Jan (janneke) Nieuwenhuizen 
<janneke@gnu.org>
+ *
+ * This file is part of GNU Mes.
+ *
+ * GNU Mes 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 of the License, or (at
+ * your option) any later version.
+ *
+ * GNU Mes 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 GNU Mes.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "mes/lib-mini.h"
+
+#define SYS_exit    93
+
+// *INDENT-OFF*
+void
+_exit (int code)
+{
+  register long __a7 asm ("a7") = SYS_exit;
+  register long __a0 asm ("a0") = code;
+  asm volatile (
+       "ecall\n\t"
+       : // no outputs
+       : "r" (__a0), "r" (__a7)
+       );
+  // not reached
+  _exit (0);
+}
diff --git a/lib/linux/riscv64-mes-gcc/_write.c 
b/lib/linux/riscv64-mes-gcc/_write.c
new file mode 100644
index 
0000000000000000000000000000000000000000..fd154e5fc8a4dff84486c2b0e07b6616ec745d5a
--- /dev/null
+++ b/lib/linux/riscv64-mes-gcc/_write.c
@@ -0,0 +1,40 @@
+/* -*-comment-start: "//";comment-end:""-*-
+ * GNU Mes --- Maxwell Equations of Software
+ * Copyright © 2016,2017,2019,2020 Jan (janneke) Nieuwenhuizen 
<janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
+ *
+ * This file is part of GNU Mes.
+ *
+ * GNU Mes 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 of the License, or (at
+ * your option) any later version.
+ *
+ * GNU Mes 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 GNU Mes.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "mes/lib-mini.h"
+
+#define SYS_write   64
+
+// *INDENT-OFF*
+ssize_t
+_write (int filedes, void const *buffer, size_t size)
+{
+  register long __a7 asm ("a7") = (long) SYS_write;
+  register long __a0 asm ("a0") = (long) filedes;
+  register long __a1 asm ("a1") = (long) buffer;
+  register long __a2 asm ("a2") = (long) size;
+  asm volatile (
+       "ecall\n\t"
+       : "+r" (__a0)
+       : "r" (__a7), "r" (__a1), "r" (__a2)
+       );
+  return (ssize_t)__a0;
+}
diff --git a/lib/linux/riscv64-mes-gcc/crt1.c b/lib/linux/riscv64-mes-gcc/crt1.c
new file mode 100644
index 
0000000000000000000000000000000000000000..e0a2e22e587bfbdf887a9dbca932fc8c8eb6cf47
--- /dev/null
+++ b/lib/linux/riscv64-mes-gcc/crt1.c
@@ -0,0 +1,90 @@
+/* -*-comment-start: "//";comment-end:""-*-
+ * GNU Mes --- Maxwell Equations of Software
+ * Copyright © 2017,2018,2019,2020 Jan (janneke) Nieuwenhuizen 
<janneke@gnu.org>
+ * Copyright © 2019,2020 Danny Milosavljevic <dannym@scratchpost.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
+ *
+ * This file is part of GNU Mes.
+ *
+ * GNU Mes 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 of the License, or (at
+ * your option) any later version.
+ *
+ * GNU Mes 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 GNU Mes.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <mes/lib-mini.h>
+//int main (int argc, char *argv[], char *envp[]);
+
+/* gcc will generate the following preamble:
+
+   addi    sp,sp,-16
+   sd      s0,8(sp)
+   addi    s0,sp,16
+*/
+
+// *INDENT-OFF*
+void
+_start ()
+{
+  asm (
+       ".option push\n\t"
+       ".option norelax\n\t"
+       "lla   gp, __global_pointer$\n\t"
+       ".option pop\n\t"
+       "andi  sp, sp, ~15\n\t" // make sure sp conforms to ABI alignment
+      );
+
+  asm (
+       "li    t0, 0\n\t"
+       "mv    %0, t0\n"
+       : "=r" (__stdin)
+       : //no inputs ""
+       );
+
+  asm (
+       "li    t0, 1\n\t"
+       "mv    %0, t0\n"
+       : "=r" (__stdout)
+       : //no inputs ""
+       );
+
+  asm (
+       "li    t0, 2\n\t"
+       "mv    %0, t0\n"
+       : "=r" (__stderr)
+       : //no inputs ""
+       );
+
+  // environ is &argv[argc + 1]
+  asm (
+       "lw    t0, 0(s0)\n\t"
+       "addi  t1, s0, 8\n\t"
+       "addi  t0, t0, 1\n\t"
+       "slli  t0, t0, 3\n\t"
+       "add   %0, t1, t0\n\t"
+       : "=r" (environ)
+       : //no inputs ""
+       );
+
+  asm (
+       "lw    a0, 0(s0)\n\t"  // a0 argc
+       "addi  a1, s0, 8\n\t"  // a1 argv
+       "mv    a2, %0\n\t"     // a2 envp
+       "jal   main\n\t"
+
+       "li    a7, 93\n\t"     // SYS_exit
+       "ecall\n\t"            // exit(return value from main)
+
+       "ebreak\n\t"
+       : //no outputs ""
+       : "r" (environ)
+       );
+}
diff --git a/lib/linux/riscv64-mes-gcc/syscall-internal.c 
b/lib/linux/riscv64-mes-gcc/syscall-internal.c
new file mode 100644
index 
0000000000000000000000000000000000000000..083029030bc87eaf61fd504dbf321e6c3e2e6b99
--- /dev/null
+++ b/lib/linux/riscv64-mes-gcc/syscall-internal.c
@@ -0,0 +1,62 @@
+/* -*-comment-start: "//";comment-end:""-*-
+ * GNU Mes --- Maxwell Equations of Software
+ * Copyright © 2016,2017,2018,2019 Jan (janneke) Nieuwenhuizen 
<janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
+ *
+ * This file is part of GNU Mes.
+ *
+ * GNU Mes 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 of the License, or (at
+ * your option) any later version.
+ *
+ * GNU Mes 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 GNU Mes.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/riscv64/syscall.h>
+
+// *INDENT-OFF*
+static long
+__sys_call_internal (long sys_call)
+{
+  register long __a7 asm ("a7") = sys_call;
+  register long __a0 asm ("a0");
+  asm volatile (
+       "ecall\n\t"
+       : "=r" (__a0)
+       : "r" (__a7)
+       );
+  return __a0;
+}
+
+static long
+__sys_call2_internal (long sys_call, long one, long two)
+{
+  register long __a7 asm ("a7") = sys_call;
+  register long __a0 asm ("a0") = one;
+  register long __a1 asm ("a1") = two;
+  asm volatile (
+       "ecall\n\t"
+       : "+r" (__a0)
+       : "r" (__a7), "r" (__a1)
+       );
+  return __a0;
+}
+// *INDENT-ON*
+
+/* Returns < 0 on error (errno-like value from kernel), or 0 on success */
+int
+__raise (int signum)
+{
+  long pid = __sys_call_internal (SYS_getpid);
+  if (pid < 0)
+    return pid;
+  else
+    return __sys_call2_internal (SYS_kill, pid, signum);
+}
diff --git a/lib/linux/riscv64-mes-gcc/syscall.c 
b/lib/linux/riscv64-mes-gcc/syscall.c
new file mode 100644
index 
0000000000000000000000000000000000000000..b9006a495492718b137f00a1465b3d6026659de3
--- /dev/null
+++ b/lib/linux/riscv64-mes-gcc/syscall.c
@@ -0,0 +1,166 @@
+/* -*-comment-start: "//";comment-end:""-*-
+ * GNU Mes --- Maxwell Equations of Software
+ * Copyright © 2016,2017,2018 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+ * Copyright © 2021 W. J. van der Laan <laanwj@protonmail.com>
+ *
+ * This file is part of GNU Mes.
+ *
+ * GNU Mes 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 of the License, or (at
+ * your option) any later version.
+ *
+ * GNU Mes 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 GNU Mes.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <errno.h>
+#include <linux/riscv64/syscall.h>
+
+// *INDENT-OFF*
+long
+__sys_call (long sys_call)
+{
+  register long __a7 asm ("a7") = sys_call;
+  register long __a0 asm ("a0");
+  asm volatile (
+       "ecall\n\t"
+       : "=r" (__a0)
+       : "r" (__a7)
+       );
+  return __a0;
+}
+
+long
+__sys_call1 (long sys_call, long one)
+{
+  register long __a7 asm ("a7") = sys_call;
+  register long __a0 asm ("a0") = one;
+  asm volatile (
+       "ecall\n\t"
+       : "+r" (__a0)
+       : "r" (__a7)
+       );
+  return __a0;
+}
+
+long
+__sys_call2 (long sys_call, long one, long two)
+{
+  register long __a7 asm ("a7") = sys_call;
+  register long __a0 asm ("a0") = one;
+  register long __a1 asm ("a1") = two;
+  asm volatile (
+       "ecall\n\t"
+       : "+r" (__a0)
+       : "r" (__a7), "r" (__a1)
+       );
+  return __a0;
+}
+
+long
+__sys_call3 (long sys_call, long one, long two, long three)
+{
+  register long __a7 asm ("a7") = sys_call;
+  register long __a0 asm ("a0") = one;
+  register long __a1 asm ("a1") = two;
+  register long __a2 asm ("a2") = three;
+  asm volatile (
+       "ecall\n\t"
+       : "+r" (__a0)
+       : "r" (__a7), "r" (__a1), "r" (__a2)
+       );
+  return __a0;
+}
+
+long
+__sys_call4 (long sys_call, long one, long two, long three, long four)
+{
+  register long __a7 asm ("a7") = sys_call;
+  register long __a0 asm ("a0") = one;
+  register long __a1 asm ("a1") = two;
+  register long __a2 asm ("a2") = three;
+  register long __a3 asm ("a3") = four;
+  asm volatile (
+       "ecall\n\t"
+       : "+r" (__a0)
+       : "r" (__a7), "r" (__a1), "r" (__a2), "r" (__a3)
+       );
+  return __a0;
+}
+// *INDENT-ON*
+
+long
+_sys_call (long sys_call)
+{
+  long r = __sys_call (sys_call);
+  if (r < 0)
+    {
+      errno = -r;
+      r = -1;
+    }
+  else
+    errno = 0;
+  return r;
+}
+
+long
+_sys_call1 (long sys_call, long one)
+{
+  long r = __sys_call1 (sys_call, one);
+  if (r < 0)
+    {
+      errno = -r;
+      r = -1;
+    }
+  else
+    errno = 0;
+  return r;
+}
+
+long
+_sys_call2 (long sys_call, long one, long two)
+{
+  long r = __sys_call2 (sys_call, one, two);
+  if (r < 0)
+    {
+      errno = -r;
+      r = -1;
+    }
+  else
+    errno = 0;
+  return r;
+}
+
+long
+_sys_call3 (long sys_call, long one, long two, long three)
+{
+  long r = __sys_call3 (sys_call, one, two, three);
+  if (r < 0)
+    {
+      errno = -r;
+      r = -1;
+    }
+  else
+    errno = 0;
+  return r;
+}
+
+long
+_sys_call4 (long sys_call, long one, long two, long three, long four)
+{
+  long r = __sys_call4 (sys_call, one, two, three, four);
+  if (r < 0)
+    {
+      errno = -r;
+      r = -1;
+    }
+  else
+    errno = 0;
+  return r;
+}
--
2.27.0