| author |  Andrew Kelley <andrew@ziglang.org> 2022-07-27 17:54:38-07:00 |
| committer | Andrew Kelley <andrew@ziglang.org> 2022-07-27 17:56:15-07:00 |
| log | 3ba7098a173be4fef3b527605b89f90d39b86a4a |
| tree | 638f720edcd873d4e2d0a4735d20d70a9ec81082 |
| parent | 6a4df2778e5f35fb112d87b12f94d4e3d06ee1d3 |
LLVM: fix returning extern union with C callconv
2 files changed, 45 insertions(+), 3 deletions(-)
src/codegen/llvm.zig+15-3
| ... | ... | @@ -4491,17 +4491,29 @@ pub const FuncGen = struct { |
| 4491 | 4491 | } |
| 4492 | 4492 | return null; |
| 4493 | 4493 | } |
| 4494 | ||
| 4494 | 4495 | const abi_ret_ty = try lowerFnRetTy(self.dg, fn_info); |
| 4496 | const ptr_abi_ty = abi_ret_ty.pointerType(0); | |
| 4495 | 4497 | const operand = try self.resolveInst(un_op); |
| 4498 | const target = self.dg.module.getTarget(); | |
| 4499 | const alignment = ret_ty.abiAlignment(target); | |
| 4500 | ||
| 4501 | if (isByRef(ret_ty)) { | |
| 4502 | // operand is a pointer however self.ret_ptr is null so that means | |
| 4503 | // we need to return a value. | |
| 4504 | const casted_ptr = self.builder.buildBitCast(operand, ptr_abi_ty, ""); | |
| 4505 | const load_inst = self.builder.buildLoad(casted_ptr, ""); | |
| 4506 | load_inst.setAlignment(alignment); | |
| 4507 | _ = self.builder.buildRet(load_inst); | |
| 4508 | return null; | |
| 4509 | } | |
| 4510 | ||
| 4496 | 4511 | const llvm_ret_ty = operand.typeOf(); |
| 4497 | 4512 | if (abi_ret_ty == llvm_ret_ty) { |
| 4498 | 4513 | _ = self.builder.buildRet(operand); |
| 4499 | 4514 | return null; |
| 4500 | 4515 | } |
| 4501 | 4516 | |
| 4502 | const target = self.dg.module.getTarget(); | |
| 4503 | const alignment = ret_ty.abiAlignment(target); | |
| 4504 | const ptr_abi_ty = abi_ret_ty.pointerType(0); | |
| 4505 | 4517 | const rp = self.buildAlloca(llvm_ret_ty); |
| 4506 | 4518 | rp.setAlignment(alignment); |
| 4507 | 4519 | const store_inst = self.builder.buildStore(operand, rp); |
test/behavior/union.zig+30
| ... | ... | @@ -1226,3 +1226,33 @@ test "extern union most-aligned field is smaller" { |
| 1226 | 1226 | var a: ?U = .{ .un = [_]u8{0} ** 110 }; |
| 1227 | 1227 | try expect(a != null); |
| 1228 | 1228 | } |
| 1229 | ||
| 1230 | test "return an extern union from C calling convention" { | |
| 1231 | if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO | |
| 1232 | if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO | |
| 1233 | if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO | |
| 1234 | ||
| 1235 | const namespace = struct { | |
| 1236 | const S = extern struct { | |
| 1237 | x: c_int, | |
| 1238 | }; | |
| 1239 | const U = extern union { | |
| 1240 | l: c_long, | |
| 1241 | d: f64, | |
| 1242 | s: S, | |
| 1243 | }; | |
| 1244 | ||
| 1245 | fn bar(arg_u: U) callconv(.C) U { | |
| 1246 | var u = arg_u; | |
| 1247 | return u; | |
| 1248 | } | |
| 1249 | }; | |
| 1250 | ||
| 1251 | var u: namespace.U = namespace.U{ | |
| 1252 | .l = @as(c_long, 42), | |
| 1253 | }; | |
| 1254 | u = namespace.bar(namespace.U{ | |
| 1255 | .d = 4.0, | |
| 1256 | }); | |
| 1257 | try expect(u.d == 4.0); | |
| 1258 | } |