Commit b0bcd4add29b6fbbe2bbc22719703d3c81ed594b | zig

author	Veikka Tuominen <git@vexu.eu> 2022-08-22 10:17:58+03:00
committer	Veikka Tuominen <git@vexu.eu> 2022-08-22 11:16:36+03:00
log	b0bcd4add29b6fbbe2bbc22719703d3c81ed594b
tree	8604903fa493cc8f9f328ffcefcd2bcea2f8b8bb
parent	74c7782c6083d398a4f0f126a4597c605d5223cd

Sema: allow optional pointers in packed structs

Closes #12572

3 files changed, 19 insertions(+), 4 deletions(-)

src
- Sema.zig
- codegen
  - llvm.zig
test
- behavior
  - packed-struct.zig

src/Sema.zig+1-1

 @@ -20565,8 +20565,8 @@ fn validatePackedType(ty: Type) bool {
         .AnyFrame,
         .Fn,
         .Array,
-        .Optional,
         => return false,
+        .Optional => return ty.isPtrLikeOptional(),
         .Void,
         .Bool,
         .Float,

src/codegen/llvm.zig+6-3

test/behavior/packed-struct.zig+12

...	@@ -434,3 +434,15 @@ test "@ptrToInt on a packed struct field" {	...	@@ -434,3 +434,15 @@ test "@ptrToInt on a packed struct field" {
434	};	434	};
435	try expect(@ptrToInt(&S.p0.z) - @ptrToInt(&S.p0.x) == 2);	435	try expect(@ptrToInt(&S.p0.z) - @ptrToInt(&S.p0.x) == 2);
436	}	436	}
		437
		438	test "optional pointer in packed struct" {
		439	if (builtin.zig_backend == .stage2_x86_64) return error.SkipZigTest;
		440	if (builtin.zig_backend == .stage2_aarch64) return error.SkipZigTest;
		441	if (builtin.zig_backend == .stage2_arm) return error.SkipZigTest;
		442	if (builtin.zig_backend == .stage2_wasm) return error.SkipZigTest;
		443
		444	const T = packed struct { ptr: ?*const u8 };
		445	var n: u8 = 0;
		446	const x = T{ .ptr = &n };
		447	try expect(x.ptr.? == &n);
		448	}

...	@@ -3417,7 +3417,10 @@ pub const DeclGen = struct {	...	@@ -3417,7 +3417,10 @@ pub const DeclGen = struct {
3417	});	3417	});
3418	const ty_bit_size = @intCast(u16, field.ty.bitSize(target));	3418	const ty_bit_size = @intCast(u16, field.ty.bitSize(target));
3419	const small_int_ty = dg.context.intType(ty_bit_size);	3419	const small_int_ty = dg.context.intType(ty_bit_size);
3420	const small_int_val = non_int_val.constBitCast(small_int_ty);	3420	const small_int_val = if (field.ty.isPtrAtRuntime())
		3421	non_int_val.constPtrToInt(small_int_ty)
		3422	else
		3423	non_int_val.constBitCast(small_int_ty);
3421	const shift_rhs = int_llvm_ty.constInt(running_bits, .False);	3424	const shift_rhs = int_llvm_ty.constInt(running_bits, .False);
3422	// If the field is as large as the entire packed struct, this	3425	// If the field is as large as the entire packed struct, this
3423	// zext would go from, e.g. i16 to i16. This is legal with	3426	// zext would go from, e.g. i16 to i16. This is legal with
...	@@ -5343,7 +5346,7 @@ pub const FuncGen = struct {	...	@@ -5343,7 +5346,7 @@ pub const FuncGen = struct {
5343	const same_size_int = self.context.intType(elem_bits);	5346	const same_size_int = self.context.intType(elem_bits);
5344	const truncated_int = self.builder.buildTrunc(shifted_value, same_size_int, "");	5347	const truncated_int = self.builder.buildTrunc(shifted_value, same_size_int, "");
5345	return self.builder.buildBitCast(truncated_int, elem_llvm_ty, "");	5348	return self.builder.buildBitCast(truncated_int, elem_llvm_ty, "");
5346	} else if (field_ty.zigTypeTag() == .Pointer) {	5349	} else if (field_ty.isPtrAtRuntime()) {
5347	const elem_bits = @intCast(c_uint, field_ty.bitSize(target));	5350	const elem_bits = @intCast(c_uint, field_ty.bitSize(target));
5348	const same_size_int = self.context.intType(elem_bits);	5351	const same_size_int = self.context.intType(elem_bits);
5349	const truncated_int = self.builder.buildTrunc(shifted_value, same_size_int, "");	5352	const truncated_int = self.builder.buildTrunc(shifted_value, same_size_int, "");
...	@@ -8408,7 +8411,7 @@ pub const FuncGen = struct {	...	@@ -8408,7 +8411,7 @@ pub const FuncGen = struct {
8408	const non_int_val = try self.resolveInst(elem);	8411	const non_int_val = try self.resolveInst(elem);
8409	const ty_bit_size = @intCast(u16, field.ty.bitSize(target));	8412	const ty_bit_size = @intCast(u16, field.ty.bitSize(target));
8410	const small_int_ty = self.dg.context.intType(ty_bit_size);	8413	const small_int_ty = self.dg.context.intType(ty_bit_size);
8411	const small_int_val = if (field.ty.zigTypeTag() == .Pointer)	8414	const small_int_val = if (field.ty.isPtrAtRuntime())
8412	self.builder.buildPtrToInt(non_int_val, small_int_ty, "")	8415	self.builder.buildPtrToInt(non_int_val, small_int_ty, "")
8413	else	8416	else
8414	self.builder.buildBitCast(non_int_val, small_int_ty, "");	8417	self.builder.buildBitCast(non_int_val, small_int_ty, "");