Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Treat field access into a class value expression as a value expression. #3357

Merged
merged 1 commit into from
Nov 2, 2023
Merged

Treat field access into a class value expression as a value expression. #3357

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
19 changes: 15 additions & 4 deletions toolchain/check/handle_name.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -108,10 +108,21 @@ auto HandleMemberAccessExpression(Context& context, Parse::Node parse_node)
CARBON_CHECK(field)
<< "Unexpected value " << context.nodes().Get(field_id)
<< " for field name expression";
context.AddNodeAndPush(
parse_node, SemIR::ClassFieldAccess{
parse_node, unbound_field_type->field_type_id,
base_id, field->index});
auto access_id = context.AddNode(SemIR::ClassFieldAccess{
parse_node, unbound_field_type->field_type_id, base_id,
field->index});
if (SemIR::GetExpressionCategory(context.sem_ir(), base_id) ==
SemIR::ExpressionCategory::Value &&
SemIR::GetExpressionCategory(context.sem_ir(), access_id) !=
SemIR::ExpressionCategory::Value) {
// Class field access on a value expression produces an ephemeral
// reference if the class's value representation is a pointer to the
// object representation. Add a value binding in that case so that the
// expression category of the result matches the expression category
// of the base.
access_id = ConvertToValueExpression(context, access_id);
}
context.node_stack().Push(parse_node, access_id);
return true;
}
if (member_type_id ==
Expand Down
81 changes: 81 additions & 0 deletions toolchain/check/testdata/class/fail_memaccess_category.carbon
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,81 @@
// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
// AUTOUPDATE

class A {
fn F[addr self: A*]();
}

class B {
var a: A;
}

fn F(s: {.a: A}, b: B) {
// `s` has only a value representation, so this must be invalid.
// CHECK:STDERR: fail_memaccess_category.carbon:[[@LINE+6]]:8: ERROR: `addr self` method cannot be invoked on a value.
// CHECK:STDERR: s.a.F();
// CHECK:STDERR: ^
// CHECK:STDERR: fail_memaccess_category.carbon:[[@LINE-12]]:13: Initializing `addr self` parameter of method declared here.
// CHECK:STDERR: fn F[addr self: A*]();
// CHECK:STDERR: ^
s.a.F();

// `b` has an object representation for `A`, but this is still invalid for
// consistency.
// CHECK:STDERR: fail_memaccess_category.carbon:[[@LINE+6]]:8: ERROR: `addr self` method cannot be invoked on a value.
// CHECK:STDERR: b.a.F();
// CHECK:STDERR: ^
// CHECK:STDERR: fail_memaccess_category.carbon:[[@LINE-22]]:13: Initializing `addr self` parameter of method declared here.
// CHECK:STDERR: fn F[addr self: A*]();
// CHECK:STDERR: ^
b.a.F();
}

// CHECK:STDOUT: file "fail_memaccess_category.carbon" {
// CHECK:STDOUT: class_declaration @A, ()
// CHECK:STDOUT: %A: type = class_type @A
// CHECK:STDOUT: %.loc9: type = struct_type {}
// CHECK:STDOUT: class_declaration @B, ()
// CHECK:STDOUT: %B: type = class_type @B
// CHECK:STDOUT: %.loc13: type = struct_type {.a: A}
// CHECK:STDOUT: %F: <function> = fn_decl @F.2
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: class @A {
// CHECK:STDOUT: %F: <function> = fn_decl @F.1
// CHECK:STDOUT:
// CHECK:STDOUT: !members:
// CHECK:STDOUT: .F = %F
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: class @B {
// CHECK:STDOUT: %A.ref: type = name_reference "A", file.%A
// CHECK:STDOUT: %.loc9: type = tuple_type ()
// CHECK:STDOUT: %.loc7: type = ptr_type {}
// CHECK:STDOUT: %.loc12_8.1: type = unbound_field_type B, A
// CHECK:STDOUT: %.loc12_8.2: <unbound field of class B> = field "a", member0
// CHECK:STDOUT: %a: <unbound field of class B> = bind_name "a", %.loc12_8.2
// CHECK:STDOUT:
// CHECK:STDOUT: !members:
// CHECK:STDOUT: .a = %a
// CHECK:STDOUT: }
// CHECK:STDOUT:
// CHECK:STDOUT: fn @F.1[%self.addr: A*]();
// CHECK:STDOUT:
// CHECK:STDOUT: fn @F.2(%s: {.a: A}, %b: B) {
// CHECK:STDOUT: !entry:
// CHECK:STDOUT: %.loc13: type = struct_type {.a: {}*}
// CHECK:STDOUT: %.loc11: type = ptr_type {.a: A}
// CHECK:STDOUT: %s.ref: {.a: A} = name_reference "s", %s
// CHECK:STDOUT: %.loc23_4: A = struct_access %s.ref, member0
// CHECK:STDOUT: %.loc23_6: <bound method> = bound_method %.loc23_4, @A.%F
// CHECK:STDOUT: %.loc23_8: init () = call %.loc23_6(<invalid>)
// CHECK:STDOUT: %b.ref: B = name_reference "b", %b
// CHECK:STDOUT: %.loc33_4.1: ref A = class_field_access %b.ref, member0
// CHECK:STDOUT: %.loc33_4.2: A = bind_value %.loc33_4.1
// CHECK:STDOUT: %.loc33_6: <bound method> = bound_method %.loc33_4.2, @A.%F
// CHECK:STDOUT: %.loc33_8: init () = call %.loc33_6(<invalid>)
// CHECK:STDOUT: return
// CHECK:STDOUT: }
2 changes: 1 addition & 1 deletion toolchain/check/testdata/class/field_access_in_value.carbon
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -57,9 +57,9 @@ fn Run() -> i32 {
// CHECK:STDOUT: %c: Class = bind_name "c", %.loc16
// CHECK:STDOUT: %c.ref.loc17_10: Class = name_reference "c", %c
// CHECK:STDOUT: %.loc17_11.1: ref i32 = class_field_access %c.ref.loc17_10, member0
// CHECK:STDOUT: %.loc17_11.2: i32 = bind_value %.loc17_11.1
// CHECK:STDOUT: %c.ref.loc17_16: Class = name_reference "c", %c
// CHECK:STDOUT: %.loc17_17.1: ref i32 = class_field_access %c.ref.loc17_16, member1
// CHECK:STDOUT: %.loc17_11.2: i32 = bind_value %.loc17_11.1
// CHECK:STDOUT: %.loc17_17.2: i32 = bind_value %.loc17_17.1
// CHECK:STDOUT: %.loc17_14: i32 = add %.loc17_11.2, %.loc17_17.2
// CHECK:STDOUT: return %.loc17_14
Expand Down
22 changes: 19 additions & 3 deletions toolchain/lower/testdata/class/value_access.carbon
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -9,6 +9,9 @@ class C {
}

fn F(c: C) -> i32 {
// TODO: `c.a` is a value expression here, which forces a value binding as
// part of the member access, creating a tuple value temporary. We could
// defer performing the value binding to avoid creating this temporary.
return c.a[1];
}

Expand All @@ -17,7 +20,20 @@ fn F(c: C) -> i32 {
// CHECK:STDOUT:
// CHECK:STDOUT: define i32 @F(ptr %c) {
// CHECK:STDOUT: %a = getelementptr inbounds { { i32, i32, i32 } }, ptr %c, i32 0, i32 0
// CHECK:STDOUT: %tuple.index = getelementptr inbounds { i32, i32, i32 }, ptr %a, i32 0, i32 1
// CHECK:STDOUT: %1 = load i32, ptr %tuple.index, align 4
// CHECK:STDOUT: ret i32 %1
// CHECK:STDOUT: %tuple.elem = getelementptr inbounds { i32, i32, i32 }, ptr %a, i32 0, i32 0
// CHECK:STDOUT: %1 = load i32, ptr %tuple.elem, align 4
// CHECK:STDOUT: %tuple.elem1 = getelementptr inbounds { i32, i32, i32 }, ptr %a, i32 0, i32 1
// CHECK:STDOUT: %2 = load i32, ptr %tuple.elem1, align 4
// CHECK:STDOUT: %tuple.elem2 = getelementptr inbounds { i32, i32, i32 }, ptr %a, i32 0, i32 2
// CHECK:STDOUT: %3 = load i32, ptr %tuple.elem2, align 4
// CHECK:STDOUT: %tuple = alloca { i32, i32, i32 }, align 8
// CHECK:STDOUT: %4 = getelementptr inbounds { i32, i32, i32 }, ptr %tuple, i32 0, i32 0
// CHECK:STDOUT: store i32 %1, ptr %4, align 4
// CHECK:STDOUT: %5 = getelementptr inbounds { i32, i32, i32 }, ptr %tuple, i32 0, i32 1
// CHECK:STDOUT: store i32 %2, ptr %5, align 4
// CHECK:STDOUT: %6 = getelementptr inbounds { i32, i32, i32 }, ptr %tuple, i32 0, i32 2
// CHECK:STDOUT: store i32 %3, ptr %6, align 4
// CHECK:STDOUT: %tuple.index = getelementptr inbounds { i32, i32, i32 }, ptr %tuple, i32 0, i32 1
// CHECK:STDOUT: %tuple.index.load = load i32, ptr %tuple.index, align 4
// CHECK:STDOUT: ret i32 %tuple.index.load
// CHECK:STDOUT: }
Loading