From bba3570788c487489a3632bc68f29c37dcb17a85 Mon Sep 17 00:00:00 2001
From: mlokr <jdoka@crownsterling.io>
Date: Tue, 17 Sep 2024 15:47:23 +0200
Subject: [PATCH] adding wide return move for wider range of cases

---
 hblang/README.md                        | 13 +++++++++
 hblang/src/codegen.rs                   | 36 +++++++++++++++++++------
 hblang/tests/codegen_tests_wide_ret.txt |  0
 3 files changed, 41 insertions(+), 8 deletions(-)
 create mode 100644 hblang/tests/codegen_tests_wide_ret.txt

diff --git a/hblang/README.md b/hblang/README.md
index d58e63f..af15fe3 100644
--- a/hblang/README.md
+++ b/hblang/README.md
@@ -356,6 +356,19 @@ main := fn(): int {
 }
 ```
 
+#### wide_ret
+```hb
+OemIdent := struct {
+	dos_version: [u8; 8],
+	dos_version_name: [u8; 8],
+}
+
+main := fn(major: int, minor: int): OemIdent {
+	ver := [u8].(0, 0, 0, 0, 0, 0, 0, 0)
+	return OemIdent.(ver, ver)
+}
+```
+
 ### Incomplete Examples
 
 #### comptime_pointers
diff --git a/hblang/src/codegen.rs b/hblang/src/codegen.rs
index 48d768c..2f4a8ec 100644
--- a/hblang/src/codegen.rs
+++ b/hblang/src/codegen.rs
@@ -1375,11 +1375,11 @@ impl Codegen {
                         Some(self.ci.inline_ret_loc.as_ref())
                     }
                     0 => None,
-                    1..=8 => Some(Loc::reg(1)),
-                    9..=16 => None,
+                    1..=16 => Some(Loc::reg(1)),
+                    //9..=16 => None,
                     _ => Some(Loc::reg(self.ci.ret_reg.as_ref()).into_derefed()),
                 };
-                let loc_is_none = loc.is_none();
+                //let loc_is_none = loc.is_none();
                 let value = if let Some(val) = val {
                     self.expr_ctx(val, Ctx { ty: self.ci.ret, loc })?
                 } else {
@@ -1391,11 +1391,11 @@ impl Codegen {
                     Some(ret) => _ = self.assert_ty(pos, value.ty, ret, "return type"),
                 }
 
-                if let 9..=16 = size
-                    && loc_is_none
-                {
-                    self.store_sized(value.loc, Loc::reg(1), size);
-                }
+                //if let 9..=16 = size
+                //    && loc_is_none
+                //{
+                //    self.store_sized(value.loc, Loc::reg(1), size);
+                //}
 
                 self.ci.ret_relocs.push(Reloc::new(self.ci.code.len(), 1, 4));
                 self.ci.emit(jmp(0));
@@ -2286,6 +2286,25 @@ impl Codegen {
                     self.ci.emit(cp(dst.get(), src.get()));
                 }
             }
+            (lpat!(false, src, 0, None), lpat!(false, dst, off, None)) => {
+                assert!(size <= 8);
+                let off_rem = 8 * (off % 8);
+                let freg = dst.get() + (off / 8) as u8;
+                if size < 8 {
+                    let mask = !(((1u64 << (8 * size)) - 1) << off_rem);
+                    self.ci.emit(andi(freg, freg, mask));
+                    if off_rem == 0 {
+                        self.ci.emit(or(freg, freg, src.get()));
+                    } else {
+                        let tmp = self.ci.regs.allocate();
+                        self.ci.emit(slui64(tmp.get(), src.get(), off_rem as _));
+                        self.ci.emit(or(freg, freg, src.get()));
+                        self.ci.regs.free(tmp);
+                    }
+                } else {
+                    self.ci.emit(cp(freg, src.get()));
+                }
+            }
             (lpat!(true, src, soff, ref ssta), lpat!(false, dst, 0, None)) => {
                 if size < 8 {
                     self.ci.emit(cp(dst.get(), 0));
@@ -2748,5 +2767,6 @@ mod tests {
         writing_into_string => README;
         request_page => README;
         tests_ptr_to_ptr_copy => README;
+        wide_ret => README;
     }
 }
diff --git a/hblang/tests/codegen_tests_wide_ret.txt b/hblang/tests/codegen_tests_wide_ret.txt
new file mode 100644
index 0000000..e69de29