zig

commit ccefa9dbf5369e0fadc75b9e705e74ec96a02859 (tree)
parent ac68d72d244fafb601725d22631f7834fb14212c
Author: Jacob Young <jacobly0@users.noreply.github.com>
Date:   Fri, 31 Mar 2023 23:47:17 -0400

x86_64: implement calling var args functions

Diffstat:
M
src/arch/x86_64/CodeGen.zig
 | 
15
+++++++++++----

1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/src/arch/x86_64/CodeGen.zig b/src/arch/x86_64/CodeGen.zig
@@ -316,7 +316,7 @@ pub fn generate(
     defer function.mir_extra.deinit(bin_file.allocator);
     defer if (builtin.mode == .Debug) function.mir_to_air_map.deinit();
 
-    var call_info = function.resolveCallingConventionValues(fn_type) catch |err| switch (err) {
+    var call_info = function.resolveCallingConventionValues(fn_type, &.{}) catch |err| switch (err) {
         error.CodegenFail => return Result{ .fail = function.err_msg.? },
         error.OutOfRegisters => return Result{
             .fail = try ErrorMsg.create(
@@ -5191,7 +5191,7 @@ fn airCall(self: *Self, inst: Air.Inst.Index, modifier: std.builtin.CallModifier
         else => unreachable,
     };
 
-    var info = try self.resolveCallingConventionValues(fn_ty);
+    var info = try self.resolveCallingConventionValues(fn_ty, args[fn_ty.fnParamLen()..]);
     defer info.deinit(self);
 
     try self.spillEflagsIfOccupied();
@@ -8089,11 +8089,18 @@ const CallMCValues = struct {
 };
 
 /// Caller must call `CallMCValues.deinit`.
-fn resolveCallingConventionValues(self: *Self, fn_ty: Type) !CallMCValues {
+fn resolveCallingConventionValues(
+    self: *Self,
+    fn_ty: Type,
+    var_args: []const Air.Inst.Ref,
+) !CallMCValues {
     const cc = fn_ty.fnCallingConvention();
-    const param_types = try self.gpa.alloc(Type, fn_ty.fnParamLen());
+    const param_len = fn_ty.fnParamLen();
+    const param_types = try self.gpa.alloc(Type, param_len + var_args.len);
     defer self.gpa.free(param_types);
     fn_ty.fnParamTypes(param_types);
+    // TODO: promote var arg types
+    for (param_types[param_len..], var_args) |*param_ty, arg| param_ty.* = self.air.typeOf(arg);
     var result: CallMCValues = .{
         .args = try self.gpa.alloc(MCValue, param_types.len),
         // These undefined values must be populated before returning from this function.