Commit 50bcfb8c90

Andrew Kelley <andrew@ziglang.org>
2021-04-01 20:58:55
stage2: implement struct init syntax with ptr result loc
1 parent 59035ae
src/AstGen.zig
@@ -769,15 +769,20 @@ pub fn expr(gz: *GenZir, scope: *Scope, rl: ResultLoc, node: ast.Node.Index) Inn
         .array_init_comma,
         => return mod.failNode(scope, node, "TODO implement astgen.expr for array literals", .{}),
 
-        .struct_init_one,
-        .struct_init_one_comma,
-        .struct_init_dot_two,
-        .struct_init_dot_two_comma,
+        .struct_init_one, .struct_init_one_comma => {
+            var fields: [1]ast.Node.Index = undefined;
+            return structInitExpr(gz, scope, rl, node, tree.structInitOne(&fields, node));
+        },
+        .struct_init_dot_two, .struct_init_dot_two_comma => {
+            var fields: [2]ast.Node.Index = undefined;
+            return structInitExpr(gz, scope, rl, node, tree.structInitDotTwo(&fields, node));
+        },
         .struct_init_dot,
         .struct_init_dot_comma,
+        => return structInitExpr(gz, scope, rl, node, tree.structInitDot(node)),
         .struct_init,
         .struct_init_comma,
-        => return mod.failNode(scope, node, "TODO implement astgen.expr for struct literals", .{}),
+        => return structInitExpr(gz, scope, rl, node, tree.structInit(node)),
 
         .@"anytype" => return mod.failNode(scope, node, "TODO implement astgen.expr for .anytype", .{}),
         .fn_proto_simple,
@@ -788,6 +793,53 @@ pub fn expr(gz: *GenZir, scope: *Scope, rl: ResultLoc, node: ast.Node.Index) Inn
     }
 }
 
+pub fn structInitExpr(
+    gz: *GenZir,
+    scope: *Scope,
+    rl: ResultLoc,
+    node: ast.Node.Index,
+    struct_init: ast.full.StructInit,
+) InnerError!zir.Inst.Ref {
+    const tree = gz.tree();
+    const astgen = gz.astgen;
+    const mod = astgen.mod;
+    const gpa = mod.gpa;
+    switch (rl) {
+        .discard => return mod.failNode(scope, node, "TODO implement structInitExpr discard", .{}),
+        .none => return mod.failNode(scope, node, "TODO implement structInitExpr none", .{}),
+        .ref => unreachable, // struct literal not valid as l-value
+        .ty => |ty_inst| {
+            return mod.failNode(scope, node, "TODO implement structInitExpr ty", .{});
+        },
+        .ptr => |ptr_inst| {
+            const field_ptr_list = try gpa.alloc(zir.Inst.Index, struct_init.ast.fields.len);
+            defer gpa.free(field_ptr_list);
+
+            for (struct_init.ast.fields) |field_init, i| {
+                const name_token = tree.firstToken(field_init) - 2;
+                const str_index = try gz.identAsString(name_token);
+                const field_ptr = try gz.addPlNode(.field_ptr, field_init, zir.Inst.Field{
+                    .lhs = ptr_inst,
+                    .field_name_start = str_index,
+                });
+                field_ptr_list[i] = astgen.refToIndex(field_ptr).?;
+                _ = try expr(gz, scope, .{ .ptr = field_ptr }, field_init);
+            }
+            const validate_inst = try gz.addPlNode(.validate_struct_init_ptr, node, zir.Inst.Block{
+                .body_len = @intCast(u32, field_ptr_list.len),
+            });
+            try astgen.extra.appendSlice(gpa, field_ptr_list);
+            return validate_inst;
+        },
+        .inferred_ptr => |ptr_inst| {
+            return mod.failNode(scope, node, "TODO implement structInitExpr inferred_ptr", .{});
+        },
+        .block_ptr => |block_gz| {
+            return mod.failNode(scope, node, "TODO implement structInitExpr block", .{});
+        },
+    }
+}
+
 pub fn comptimeExpr(
     gz: *GenZir,
     scope: *Scope,
@@ -1285,6 +1337,7 @@ fn blockExprStmts(
                         .resolve_inferred_alloc,
                         .repeat,
                         .repeat_inline,
+                        .validate_struct_init_ptr,
                         => break :b true,
                     }
                 } else switch (maybe_unused_result) {
@@ -1959,7 +2012,8 @@ pub fn fieldAccess(
     rl: ResultLoc,
     node: ast.Node.Index,
 ) InnerError!zir.Inst.Ref {
-    const mod = gz.astgen.mod;
+    const astgen = gz.astgen;
+    const mod = astgen.mod;
     const tree = gz.tree();
     const main_tokens = tree.nodes.items(.main_token);
     const node_datas = tree.nodes.items(.data);
@@ -1967,10 +2021,7 @@ pub fn fieldAccess(
     const object_node = node_datas[node].lhs;
     const dot_token = main_tokens[node];
     const field_ident = dot_token + 1;
-    const string_bytes = &gz.astgen.string_bytes;
-    const str_index = @intCast(u32, string_bytes.items.len);
-    try mod.appendIdentStr(scope, field_ident, string_bytes);
-    try string_bytes.append(mod.gpa, 0);
+    const str_index = try gz.identAsString(field_ident);
     switch (rl) {
         .ref => return gz.addPlNode(.field_ptr, node, zir.Inst.Field{
             .lhs = try expr(gz, scope, .ref, object_node),
@@ -2031,11 +2082,7 @@ fn simpleStrTok(
     node: ast.Node.Index,
     op_inst_tag: zir.Inst.Tag,
 ) InnerError!zir.Inst.Ref {
-    const mod = gz.astgen.mod;
-    const string_bytes = &gz.astgen.string_bytes;
-    const str_index = @intCast(u32, string_bytes.items.len);
-    try mod.appendIdentStr(scope, ident_token, string_bytes);
-    try string_bytes.append(mod.gpa, 0);
+    const str_index = try gz.identAsString(ident_token);
     const result = try gz.addStrTok(op_inst_tag, str_index, ident_token);
     return rvalue(gz, scope, rl, result, node);
 }
src/Module.zig
@@ -1046,6 +1046,16 @@ pub const Scope = struct {
             gz.astgen.extra.appendSliceAssumeCapacity(gz.instructions.items);
         }
 
+        pub fn identAsString(gz: *GenZir, ident_token: ast.TokenIndex) !u32 {
+            const astgen = gz.astgen;
+            const gpa = astgen.mod.gpa;
+            const string_bytes = &astgen.string_bytes;
+            const str_index = @intCast(u32, string_bytes.items.len);
+            try astgen.mod.appendIdentStr(&gz.base, ident_token, string_bytes);
+            try string_bytes.append(gpa, 0);
+            return str_index;
+        }
+
         pub fn addFnTypeCc(gz: *GenZir, tag: zir.Inst.Tag, args: struct {
             src_node: ast.Node.Index,
             param_types: []const zir.Inst.Ref,
src/Sema.zig
@@ -326,6 +326,10 @@ pub fn analyzeBody(
                 try sema.zirResolveInferredAlloc(block, inst);
                 continue;
             },
+            .validate_struct_init_ptr => {
+                try sema.zirValidateStructInitPtr(block, inst);
+                continue;
+            },
 
             // Special case instructions to handle comptime control flow.
             .repeat_inline => {
@@ -694,6 +698,18 @@ fn zirResolveInferredAlloc(sema: *Sema, block: *Scope.Block, inst: zir.Inst.Inde
     ptr.tag = .alloc;
 }
 
+fn zirValidateStructInitPtr(sema: *Sema, block: *Scope.Block, inst: zir.Inst.Index) InnerError!void {
+    const tracy = trace(@src());
+    defer tracy.end();
+
+    const inst_data = sema.code.instructions.items(.data)[inst].pl_node;
+    const src = inst_data.src();
+    const extra = sema.code.extraData(zir.Inst.Block, inst_data.payload_index);
+    const instrs = sema.code.extra[extra.end..][0..extra.data.body_len];
+
+    return sema.mod.fail(&block.base, src, "TODO implement zirValidateStructInitPtr", .{});
+}
+
 fn zirStoreToBlockPtr(sema: *Sema, block: *Scope.Block, inst: zir.Inst.Index) InnerError!void {
     const tracy = trace(@src());
     defer tracy.end();
src/zir.zig
@@ -637,6 +637,11 @@ pub const Inst = struct {
         /// Result is a pointer to the value.
         /// Uses the `switch_capture` field.
         switch_capture_else_ref,
+        /// Given a set of `field_ptr` instructions, assumes they are all part of a struct
+        /// initialization expression, and emits compile errors for duplicate fields
+        /// as well as missing fields, if applicable.
+        /// Uses the `pl_node` field. Payload is `Block`.
+        validate_struct_init_ptr,
 
         /// Returns whether the instruction is one of the control flow "noreturn" types.
         /// Function calls do not count.
@@ -784,6 +789,7 @@ pub const Inst = struct {
                 .switch_block_ref_else_multi,
                 .switch_block_ref_under,
                 .switch_block_ref_under_multi,
+                .validate_struct_init_ptr,
                 => false,
 
                 .@"break",
@@ -1568,6 +1574,7 @@ const Writer = struct {
             .block,
             .block_inline,
             .loop,
+            .validate_struct_init_ptr,
             => try self.writePlNodeBlock(stream, inst),
 
             .condbr,