From e5a11020cc838019de12955437b371511b4745e5 Mon Sep 17 00:00:00 2001
From: Koakuma <koachan@protonmail.com>
Date: Mon, 17 Aug 2020 15:07:57 +0700
Subject: [PATCH] Add sparc64 syscall interface

---
 lib/std/os/linux.zig         |   1 +
 lib/std/os/linux/sparc64.zig | 136 +++++++++++++++++++++++++++++++++++
 2 files changed, 137 insertions(+)
 create mode 100644 lib/std/os/linux/sparc64.zig

diff --git a/lib/std/os/linux.zig b/lib/std/os/linux.zig
index e38d9bc10d..0a675cf10f 100644
--- a/lib/std/os/linux.zig
+++ b/lib/std/os/linux.zig
@@ -24,6 +24,7 @@ pub usingnamespace switch (builtin.arch) {
     .aarch64 => @import("linux/arm64.zig"),
     .arm => @import("linux/arm-eabi.zig"),
     .riscv64 => @import("linux/riscv64.zig"),
+    .sparcv9 => @import("linux/sparc64.zig"),
     .mips, .mipsel => @import("linux/mips.zig"),
     .powerpc64, .powerpc64le => @import("linux/powerpc64.zig"),
     else => struct {},
diff --git a/lib/std/os/linux/sparc64.zig b/lib/std/os/linux/sparc64.zig
new file mode 100644
index 0000000000..0cc5882b26
--- /dev/null
+++ b/lib/std/os/linux/sparc64.zig
@@ -0,0 +1,136 @@
+usingnamespace @import("../bits.zig");
+
+// TODO: Handle the case of pipe(2) returning multiple values.
+// From syscall(2)'s manual page:
+// Some architectures (namely, Alpha, IA-64, MIPS, SuperH, sparc/32, and sparc/64)
+// use an additional register ("Retval2" in the above table) to pass back a second
+// return value from the pipe(2) system call; Alpha uses this technique in the
+// architecture-specific getxpid(2), getxuid(2), and getxgid(2) system calls
+// as well. Other architectures do not use the second return value register in
+// the system call interface, even if it is defined in the System V ABI.
+
+pub fn syscall0(number: SYS) usize {
+    return asm volatile (
+        \\ t   0x6d
+        \\ bcc %%xcc, 1f
+        \\ neg %%o0
+        \\ 1:
+        : [ret] "={%o0}" (-> usize)
+        : [number] "{%g1}" (@enumToInt(number))
+        : "memory", "%o1", "%o2", "%o3", "%o4", "%o5", "%o7"
+    );
+}
+
+pub fn syscall1(number: SYS, arg1: usize) usize {
+    return asm volatile (
+        \\ t   0x6d
+        \\ bcc %%xcc, 1f
+        \\ neg %%o0
+        \\ 1:
+        : [ret] "={%o0}" (-> usize)
+        : [number] "{%g1}" (@enumToInt(number)),
+          [arg1] "{%o0}" (arg1)
+        : "memory", "%o1", "%o2", "%o3", "%o4", "%o5", "%o7"
+    );
+}
+
+pub fn syscall2(number: SYS, arg1: usize, arg2: usize) usize {
+    return asm volatile (
+        \\ t   0x6d
+        \\ bcc %%xcc, 1f
+        \\ neg %%o0
+        \\ 1:
+        : [ret] "={%o0}" (-> usize)
+        : [number] "{%g1}" (@enumToInt(number)),
+          [arg1] "{%o0}" (arg1),
+          [arg2] "{%o1}" (arg2)
+        : "memory", "%o1", "%o2", "%o3", "%o4", "%o5", "%o7"
+    );
+}
+
+pub fn syscall3(number: SYS, arg1: usize, arg2: usize, arg3: usize) usize {
+    return asm volatile (
+        \\ t   0x6d
+        \\ bcc %%xcc, 1f
+        \\ neg %%o0
+        \\ 1:
+        : [ret] "={%o0}" (-> usize)
+        : [number] "{%g1}" (@enumToInt(number)),
+          [arg1] "{%o0}" (arg1),
+          [arg2] "{%o1}" (arg2),
+          [arg3] "{%o2}" (arg3)
+        : "memory", "%o1", "%o2", "%o3", "%o4", "%o5", "%o7"
+    );
+}
+
+pub fn syscall4(number: SYS, arg1: usize, arg2: usize, arg3: usize, arg4: usize) usize {
+    return asm volatile (
+        \\ t   0x6d
+        \\ bcc %%xcc, 1f
+        \\ neg %%o0
+        \\ 1:
+        : [ret] "={%o0}" (-> usize)
+        : [number] "{%g1}" (@enumToInt(number)),
+          [arg1] "{%o0}" (arg1),
+          [arg2] "{%o1}" (arg2),
+          [arg3] "{%o2}" (arg3),
+          [arg4] "{%o3}" (arg4)
+        : "memory", "%o1", "%o2", "%o3", "%o4", "%o5", "%o7"
+    );
+}
+
+pub fn syscall5(number: SYS, arg1: usize, arg2: usize, arg3: usize, arg4: usize, arg5: usize) usize {
+    return asm volatile (
+        \\ t   0x6d
+        \\ bcc %%xcc, 1f
+        \\ neg %%o0
+        \\ 1:
+        : [ret] "={%o0}" (-> usize)
+        : [number] "{%g1}" (@enumToInt(number)),
+          [arg1] "{%o0}" (arg1),
+          [arg2] "{%o1}" (arg2),
+          [arg3] "{%o2}" (arg3),
+          [arg4] "{%o3}" (arg4),
+          [arg5] "{%o4}" (arg5),
+        : "memory", "%o1", "%o2", "%o3", "%o4", "%o5", "%o7"
+    );
+}
+
+pub fn syscall6(
+    number: SYS,
+    arg1: usize,
+    arg2: usize,
+    arg3: usize,
+    arg4: usize,
+    arg5: usize,
+    arg6: usize,
+) usize {
+    return asm volatile (
+        \\ t   0x6d
+        \\ bcc %%xcc, 1f
+        \\ neg %%o0
+        \\ 1:
+        : [ret] "={%o0}" (-> usize)
+        : [number] "{%g1}" (@enumToInt(number)),
+          [arg1] "{%o0}" (arg1),
+          [arg2] "{%o1}" (arg2),
+          [arg3] "{%o2}" (arg3),
+          [arg4] "{%o3}" (arg4),
+          [arg5] "{%o4}" (arg5),
+          [arg6] "{%o5}" (arg6),
+        : "memory", "%o1", "%o2", "%o3", "%o4", "%o5", "%o7"
+    );
+}
+
+/// This matches the libc clone function.
+pub extern fn clone(func: fn (arg: usize) callconv(.C) u8, stack: usize, flags: usize, arg: usize, ptid: *i32, tls: usize, ctid: *i32) usize;
+
+pub const restore = restore_rt;
+
+pub fn restore_rt() callconv(.Naked) void {
+    return asm volatile ("t 0x6d"
+        :
+        : [number] "{%g1}" (@enumToInt(SYS.rt_sigreturn))
+        : "memory", "%o0", "%o1", "%o2", "%o3", "%o4", "%o5", "%o7"
+    );
+}