Description: Add support for LoongArch64 targets
Sigened-Off-By: heiher
Pull-Request: https://github.com/Xudong-Huang/generator-rs/pull/48
Last-Update: 2024-06-28

--- rust-generator-0.7.1.orig/README.md
+++ rust-generator-0.7.1/README.md
@@ -75,10 +75,11 @@ fn main() {
     - x86_64 MacOs
     - x86_64 Windows
     - aarch64 Linux
+    - loongarch64 Linux
 
 ## License
 
 This project is licensed under either of the following, at your option:
 
  * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
- * MIT License ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
\ No newline at end of file
+ * MIT License ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
--- rust-generator-0.7.1.orig/build.rs
+++ rust-generator-0.7.1/build.rs
@@ -22,6 +22,7 @@ fn main() {
         // "mips" | "mipsel" => "mips32",
         // "powerpc" => "ppc32",
         // "powerpc64" => "ppc64",
+        "loongarch64" => "loongarch64",
         "x86_64" => "x86_64",
         _ => {
             panic!("Unsupported architecture: {}", target);
--- /dev/null
+++ rust-generator-0.7.1/src/detail/asm/asm_loongarch64_sysv_elf_gas.S
@@ -0,0 +1,74 @@
+.text
+.globl prefetch
+.type prefetch,@function
+.align 16
+prefetch:
+    preld 0, $a0, 0
+    ret
+.size prefetch,.-prefetch
+
+.text
+.globl bootstrap_green_task
+.type bootstrap_green_task,@function
+.align 16
+bootstrap_green_task:
+    move $a0, $s0   // arg0
+    move $a1, $s1   // arg1
+    move $ra, $zero // clear LR
+    jirl $zero, $s2, 0
+.size bootstrap_green_task,.-bootstrap_green_task
+
+.text
+.globl swap_registers
+.type swap_registers,@function
+.align 16
+swap_registers:
+    st.d $ra, $a0, 0
+    st.d $sp, $a0, 8
+    st.d $fp, $a0, 16
+    st.d $s0, $a0, 24
+    st.d $s1, $a0, 32
+    st.d $s2, $a0, 40
+    st.d $s3, $a0, 48
+    st.d $s4, $a0, 56
+    st.d $s5, $a0, 64
+    st.d $s6, $a0, 72
+    st.d $s7, $a0, 80
+    st.d $s8, $a0, 88
+
+    fst.d $fs0, $a0, 96
+    fst.d $fs1, $a0, 104
+    fst.d $fs2, $a0, 112
+    fst.d $fs3, $a0, 120
+    fst.d $fs4, $a0, 128
+    fst.d $fs5, $a0, 136
+    fst.d $fs6, $a0, 144
+    fst.d $fs7, $a0, 152
+
+    ld.d $ra, $a1, 0
+    ld.d $sp, $a1, 8
+    ld.d $fp, $a1, 16
+    ld.d $s0, $a1, 24
+    ld.d $s1, $a1, 32
+    ld.d $s2, $a1, 40
+    ld.d $s3, $a1, 48
+    ld.d $s4, $a1, 56
+    ld.d $s5, $a1, 64
+    ld.d $s6, $a1, 72
+    ld.d $s7, $a1, 80
+    ld.d $s8, $a1, 88
+
+    fld.d $fs0, $a1, 96
+    fld.d $fs1, $a1, 104
+    fld.d $fs2, $a1, 112
+    fld.d $fs3, $a1, 120
+    fld.d $fs4, $a1, 128
+    fld.d $fs5, $a1, 136
+    fld.d $fs6, $a1, 144
+    fld.d $fs7, $a1, 152
+
+    ret
+.size swap_registers,.-swap_registers
+
+/* Mark that we don't need executable stack. */
+.section .note.GNU-stack,"",%progbits
--- /dev/null
+++ rust-generator-0.7.1/src/detail/loongarch64_unix.rs
@@ -0,0 +1,85 @@
+use crate::detail::align_down;
+use crate::reg_context::InitFn;
+use crate::stack::Stack;
+
+#[link(name = "asm", kind = "static")]
+extern "C" {
+    pub fn bootstrap_green_task();
+    pub fn prefetch(data: *const usize);
+    pub fn swap_registers(out_regs: *mut Registers, in_regs: *const Registers);
+}
+
+#[repr(C, align(16))]
+#[derive(Debug)]
+pub struct Registers {
+    // We save the 12 callee-saved registers:
+    //  0: ra
+    //  1: sp
+    //  2: fp
+    //  3: s0
+    //  4: s1
+    //  5: s2
+    //  6: s3
+    //  7: s4
+    //  8: s5
+    //  9: s6
+    // 10: s7
+    // 11: s8
+    // and the 8 callee-saved floating point registers:
+    // 12: fs0
+    // 13: fs1
+    // 14: fs2
+    // 15: fs3
+    // 16: fs4
+    // 17: fs5
+    // 18: fs6
+    // 19: fs7
+    gpr: [usize; 20],
+}
+
+impl Registers {
+    pub fn new() -> Registers {
+        Registers { gpr: [0; 20] }
+    }
+
+    #[inline]
+    pub fn prefetch(&self) {
+        let ptr = self.gpr[1] as *const usize;
+        unsafe {
+            prefetch(ptr); // SP
+            prefetch(ptr.add(8)); // SP + 8
+        }
+    }
+}
+
+pub fn initialize_call_frame(
+    regs: &mut Registers,
+    fptr: InitFn,
+    arg: usize,
+    arg2: *mut usize,
+    stack: &Stack,
+) {
+    const RA: usize = 0;
+    const SP: usize = 1;
+    const FP: usize = 2;
+    const S0: usize = 3;
+    const S1: usize = 4;
+    const S2: usize = 5;
+
+    let sp = align_down(stack.end());
+
+    // These registers are frobbed by bootstrap_green_task into the right
+    // location so we can invoke the "real init function", `fptr`.
+    regs.gpr[S0] = arg;
+    regs.gpr[S1] = arg2 as usize;
+    regs.gpr[S2] = fptr as usize;
+
+    // LoongArch64 current stack frame pointer
+    regs.gpr[FP] = sp as usize;
+
+    regs.gpr[RA] = bootstrap_green_task as usize;
+
+    // setup the init stack
+    // this is prepared for the swap context
+    regs.gpr[SP] = sp as usize;
+}
--- rust-generator-0.7.1.orig/src/detail/mod.rs
+++ rust-generator-0.7.1/src/detail/mod.rs
@@ -33,6 +33,10 @@ pub mod asm;
 #[path = "aarch64_unix.rs"]
 pub mod asm;
 
+#[cfg(all(unix, target_arch = "loongarch64"))]
+#[path = "loongarch64_unix.rs"]
+pub mod asm;
+
 pub use self::asm::{initialize_call_frame, prefetch, swap_registers, Registers};
 
 #[inline]
--- rust-generator-0.7.1.orig/src/stack/mod.rs
+++ rust-generator-0.7.1/src/stack/mod.rs
@@ -17,6 +17,10 @@ pub mod sys;
 #[path = "unix.rs"]
 pub mod sys;
 
+#[cfg(all(unix, target_arch = "loongarch64"))]
+#[path = "unix.rs"]
+pub mod sys;
+
 #[cfg(all(windows, target_arch = "x86_64"))]
 #[path = "windows.rs"]
 pub mod sys;