authorgravatar for git@vexu.euVeikka Tuominen <git@vexu.eu> 2022-04-15 19:17:50+03:00
committergravatar for git@vexu.euVeikka Tuominen <git@vexu.eu> 2022-04-15 19:17:50+03:00
log7be62f695ffb468e19241a564d544d6a0adab829
tree77d3704190ff9dde13a05767d6214a86136f7bcb
parentdbe0d3d5790d9e21cf42696d4cea8cc477207592

stage2 llvm: fix optional pointers to zero bit payloads

3 files changed, 61 insertions(+), 9 deletions(-)

lib/std/special/c.zig+2-4
......@@ -32,10 +32,8 @@ comptime {
3232 @export(wasm_start, .{ .name = "_start", .linkage = .Strong });
3333 }
3434
35 if (builtin.zig_backend == .stage1) { // TODO remove this condition
36 if (native_os == .linux) {
37 @export(clone, .{ .name = "clone" });
38 }
35 if (native_os == .linux) {
36 @export(clone, .{ .name = "clone" });
3937 }
4038
4139 @export(memset, .{ .name = "memset", .linkage = .Strong });
src/codegen/llvm.zig+20-5
......@@ -4732,10 +4732,11 @@ pub const FuncGen = struct {
47324732 var buf: Type.Payload.ElemType = undefined;
47334733 const payload_ty = optional_ty.optionalChild(&buf);
47344734 if (!payload_ty.hasRuntimeBitsIgnoreComptime()) {
4735 const loaded = if (operand_is_ptr) self.builder.buildLoad(operand, "") else operand;
47354736 if (invert) {
4736 return self.builder.buildNot(operand, "");
4737 return self.builder.buildNot(loaded, "");
47374738 } else {
4738 return operand;
4739 return loaded;
47394740 }
47404741 }
47414742
......@@ -4784,12 +4785,16 @@ pub const FuncGen = struct {
47844785 const ty_op = self.air.instructions.items(.data)[inst].ty_op;
47854786 const operand = try self.resolveInst(ty_op.operand);
47864787 const optional_ty = self.air.typeOf(ty_op.operand).childType();
4788 const result_ty = self.air.getRefType(ty_op.ty);
47874789 var buf: Type.Payload.ElemType = undefined;
47884790 const payload_ty = optional_ty.optionalChild(&buf);
47894791 if (!payload_ty.hasRuntimeBitsIgnoreComptime()) {
47904792 // We have a pointer to a zero-bit value and we need to return
47914793 // a pointer to a zero-bit value.
4792 return operand;
4794
4795 // TODO once we update to LLVM 14 this bitcast won't be necessary.
4796 const res_ptr_ty = try self.dg.llvmType(result_ty);
4797 return self.builder.buildBitCast(operand, res_ptr_ty, "");
47934798 }
47944799 if (optional_ty.isPtrLikeOptional()) {
47954800 // The payload and the optional are the same value.
......@@ -4807,13 +4812,17 @@ pub const FuncGen = struct {
48074812 const ty_op = self.air.instructions.items(.data)[inst].ty_op;
48084813 const operand = try self.resolveInst(ty_op.operand);
48094814 const optional_ty = self.air.typeOf(ty_op.operand).childType();
4815 const result_ty = self.air.getRefType(ty_op.ty);
48104816 var buf: Type.Payload.ElemType = undefined;
48114817 const payload_ty = optional_ty.optionalChild(&buf);
48124818 const non_null_bit = self.context.intType(1).constAllOnes();
48134819 if (!payload_ty.hasRuntimeBitsIgnoreComptime()) {
48144820 // We have a pointer to a i1. We need to set it to 1 and then return the same pointer.
48154821 _ = self.builder.buildStore(non_null_bit, operand);
4816 return operand;
4822
4823 // TODO once we update to LLVM 14 this bitcast won't be necessary.
4824 const res_ptr_ty = try self.dg.llvmType(result_ty);
4825 return self.builder.buildBitCast(operand, res_ptr_ty, "");
48174826 }
48184827 if (optional_ty.isPtrLikeOptional()) {
48194828 // The payload and the optional are the same value.
......@@ -4872,7 +4881,13 @@ pub const FuncGen = struct {
48724881 const target = self.dg.module.getTarget();
48734882 const offset: u8 = if (payload_ty.abiAlignment(target) > Type.anyerror.abiSize(target)) 2 else 1;
48744883
4875 if (!payload_ty.hasRuntimeBitsIgnoreComptime()) return null;
4884 if (!payload_ty.hasRuntimeBitsIgnoreComptime()) {
4885 if (!operand_is_ptr) return null;
4886
4887 // TODO once we update to LLVM 14 this bitcast won't be necessary.
4888 const res_ptr_ty = try self.dg.llvmType(result_ty);
4889 return self.builder.buildBitCast(operand, res_ptr_ty, "");
4890 }
48764891 if (operand_is_ptr or isByRef(payload_ty)) {
48774892 return self.builder.buildStructGEP(operand, offset, "");
48784893 }
test/behavior/optional.zig+39
......@@ -332,3 +332,42 @@ test "array of optional unaligned types" {
332332 i += 1;
333333 try expect(Enum.three == values[i].?.Num);
334334}
335
336test "optional pointer to zero bit optional payload" {
337 if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
338 if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
339 if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
340 if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
341
342 const B = struct {
343 fn foo(_: *@This()) void {}
344 };
345 const A = struct {
346 b: ?B = .{},
347 };
348 var a: A = .{};
349 var a_ptr = &a;
350 if (a_ptr.b) |*some| {
351 some.foo();
352 }
353}
354
355test "optional pointer to zero bit error union payload" {
356 if (builtin.zig_backend == .stage2_c) return error.SkipZigTest; // TODO
357 if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest; // TODO
358 if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest; // TODO
359 if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest; // TODO
360 if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest; // TODO
361
362 const B = struct {
363 fn foo(_: *@This()) void {}
364 };
365 const A = struct {
366 b: anyerror!B = .{},
367 };
368 var a: A = .{};
369 var a_ptr = &a;
370 if (a_ptr.b) |*some| {
371 some.foo();
372 } else |_| {}
373}