1 files changed, 14 insertions, 4 deletions

diff --git a/src/codegen.zig b/src/codegen.zig
index 0e70a0b..97e160c 100644
--- a/src/codegen.zig
+++ b/src/codegen.zig
@@ -585,6 +585,7 @@ const ProcedureContext = struct {
     register_allocator: RegisterAllocator(compile.VReg),
     lvar_allocator: RegisterAllocator(compile.LVar),
     ctx: *Context,
+    proc: compile.Procedure,
 
     // Current stuff that changes often, basically here to avoid prop drilling.
     block: ?*const compile.BasicBlock = null,
@@ -664,7 +665,7 @@ const ProcedureContext = struct {
         }
     }
 
-    fn genProcCall(self: *Self, call: compile.Instr.ProcCall) !void {
+    fn genCall(self: *Self, call: compile.Instr.Call) !void {
         const arg = self.register_allocator.get(call.arg);
 
         try self.freeUnusedVRegs();
@@ -752,17 +753,25 @@ const ProcedureContext = struct {
     fn prologue(self: *Self) !void {
         try self.emit(.addi(.sp, .sp, -8));
         try self.emit(.sd(.sp, 0, .ra));
+
+        if (self.proc.param_reg) |reg| {
+            const param = try self.register_allocator.allocate(reg);
+            try self.emit(.addi(param, .a0, 0));
+        }
     }
 
     fn epilogue(self: *Self) !void {
+        if (self.proc.param_reg) |reg| {
+            self.register_allocator.free(reg);
+        }
         try self.emit(.ld(.ra, .sp, 0));
         try self.emit(.addi(.sp, .sp, 8));
         try self.emit(.jalr(.zero, .ra, 0));
     }
 
-    fn codegenProc(self: *Self, proc: compile.Procedure) !void {
+    fn codegenProc(self: *Self) !void {
         var first = true;
-        for (proc.blocks) |block| {
+        for (self.proc.blocks) |block| {
             try self.ctx.block_addrs.putNoClobber(block.ref, self.ctx.instructions.items.len);
             if (first) {
                 try self.prologue();
@@ -866,10 +875,11 @@ pub fn create_elf(allocator: Allocator, mod: compile.Module) ![]u8 {
             .register_allocator = try .init(allocator, &.{ .t6, .t5, .t4, .t3, .t2, .t1, .t0 }),
             .lvar_allocator = try .init(allocator, &.{ .s11, .s10, .s9, .s8, .s7, .s6, .s5, .s4, .s3, .s2, .s1, .s0 }),
             .ctx = &ctx,
+            .proc = proc,
         };
         defer proc_ctx.deinit();
 
-        try proc_ctx.codegenProc(proc);
+        try proc_ctx.codegenProc();
         std.debug.assert(proc_ctx.register_allocator.allocated.count() == 0);
     }