fix(rust-irgen): Emit branch unconditional for jmp

lccc-project · Aug 27, 2023 · c7efcac · c7efcac
1 parent 3ad3ffc
commit c7efcac
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Showing 3 changed files with 24 additions and 1 deletion.
diff --git a/codegen-x86/src/mc.rs b/codegen-x86/src/mc.rs
@@ -753,6 +753,13 @@ impl MCWriter for X86MCWriter {
                 MCInsn::Label(label) => {
                     sym_accepter(label.clone(), encoder.offset() as u64);
                 }
+                MCInsn::UnconditionalBranch(label) => encoder.write_insn(X86Instruction::new(
+                    X86Opcode::Jmp,
+                    vec![X86Operand::RelAddr(Address::Symbol {
+                        name: label.clone(),
+                        disp: 0,
+                    })],
+                ))?,
                 _ => todo!(),
             }
         }

diff --git a/rust/src/irgen/xir_visitor.rs b/rust/src/irgen/xir_visitor.rs
@@ -1293,6 +1293,18 @@ impl<'a> JumpVisitor for XirJumpVisitor<'a> {
     }
 }
 
+impl<'a> Drop for XirJumpVisitor<'a> {
+    fn drop(&mut self) {
+        self.body
+            .block
+            .items
+            .push(ir::BlockItem::Expr(ir::Expr::Branch {
+                cond: ir::BranchCondition::Always,
+                target: self.targ.unwrap().id(),
+            }))
+    }
+}
+
 pub struct XirExprVisitor<'a> {
     defs: &'a Definitions,
     names: &'a NameMap,

diff --git a/xlang/xlang_backend/src/mc.rs b/xlang/xlang_backend/src/mc.rs
@@ -150,6 +150,8 @@ pub enum MCInsn<Loc> {
 
     /// A Label
     Label(String),
+    /// Unconditional Branch
+    UnconditionalBranch(String),
 }
 
 impl<Loc> Default for MCInsn<Loc> {
@@ -343,6 +345,7 @@ impl<F: MachineFeatures> FunctionRawCodegen for MCFunctionCodegen<F> {
 
     fn write_target(&mut self, target: u32) {
         let targ = format!("{}._T{}", self.fn_name, target);
+        self.mc_insns.push(MCInsn::Label(targ));
     }
 
     fn call_direct(&mut self, path: &xlang::ir::Path, realty: &xlang::ir::FnType) {
@@ -405,7 +408,8 @@ impl<F: MachineFeatures> FunctionRawCodegen for MCFunctionCodegen<F> {
     }
 
     fn branch_unconditional(&mut self, target: u32) {
-        todo!()
+        let targ = format!("{}._T{}", self.fn_name, target);
+        self.mc_insns.push(MCInsn::UnconditionalBranch(targ));
     }
 
     fn branch_indirect(&mut self, target: Self::Loc) {