astgen: update a handful of expression types to new mem layout

break, continue, blocks, bit_not, negation, identifiers, string
literals, integer literals, inline assembly

also gave multiline string literals a different node tag from regular
string literals, for code clarity and to avoid an unnecessary load from
token_tags array.

lib/std/zig/ast.zig

@@ -283,6 +283,7 @@ pub const Tree = struct {
             .undefined_literal,
             .unreachable_literal,
             .string_literal,
+            .multiline_string_literal,
             .grouped_expression,
             .builtin_call_two,
             .builtin_call_two_comma,
@@ -593,7 +594,7 @@ pub const Tree = struct {
             .field_access,
             .unwrap_optional,
             .grouped_expression,
-            .string_literal,
+            .multiline_string_literal,
             .error_set_decl,
             .asm_simple,
             .asm_output,
@@ -614,6 +615,7 @@ pub const Tree = struct {
             .identifier,
             .deref,
             .enum_literal,
+            .string_literal,
             => return main_tokens[n] + end_offset,
 
             .@"return" => if (datas[n].lhs != 0) {
@@ -2826,11 +2828,14 @@ pub const Node = struct {
         identifier,
         /// lhs is the dot token index, rhs unused, main_token is the identifier.
         enum_literal,
+        /// main_token is the string literal token
+        /// Both lhs and rhs unused.
+        string_literal,
         /// main_token is the first token index (redundant with lhs)
         /// lhs is the first token index; rhs is the last token index.
         /// Could be a series of multiline_string_literal_line tokens, or a single
         /// string_literal token.
-        string_literal,
+        multiline_string_literal,
         /// `(lhs)`. main_token is the `(`; rhs is the token index of the `)`.
         grouped_expression,
         /// `@a(lhs, rhs)`. lhs and rhs may be omitted.

lib/std/zig/parse.zig

@@ -2595,8 +2595,8 @@ const Parser = struct {
                     .tag = .string_literal,
                     .main_token = main_token,
                     .data = .{
-                        .lhs = main_token,
-                        .rhs = main_token,
+                        .lhs = undefined,
+                        .rhs = undefined,
                     },
                 });
             },
@@ -2633,7 +2633,7 @@ const Parser = struct {
                     p.tok_i += 1;
                 }
                 return p.addNode(.{
-                    .tag = .string_literal,
+                    .tag = .multiline_string_literal,
                     .main_token = first_line,
                     .data = .{
                         .lhs = first_line,
@@ -3996,8 +3996,8 @@ const Parser = struct {
                     .tag = .string_literal,
                     .main_token = main_token,
                     .data = .{
-                        .lhs = main_token,
-                        .rhs = main_token,
+                        .lhs = undefined,
+                        .rhs = undefined,
                     },
                 });
             },
@@ -4007,7 +4007,7 @@ const Parser = struct {
                     p.tok_i += 1;
                 }
                 return p.addNode(.{
-                    .tag = .string_literal,
+                    .tag = .multiline_string_literal,
                     .main_token = first_line,
                     .data = .{
                         .lhs = first_line,

lib/std/zig/render.zig

@@ -153,29 +153,25 @@ fn renderExpression(ais: *Ais, tree: ast.Tree, node: ast.Node.Index, space: Spac
         .unreachable_literal,
         .undefined_literal,
         .anyframe_literal,
+        .string_literal,
         => return renderToken(ais, tree, main_tokens[node], space),
 
-        .string_literal => switch (token_tags[main_tokens[node]]) {
-            .string_literal => try renderToken(ais, tree, main_tokens[node], space),
+        .multiline_string_literal => {
+            var locked_indents = ais.lockOneShotIndent();
+            try ais.maybeInsertNewline();
 
-            .multiline_string_literal_line => {
-                var locked_indents = ais.lockOneShotIndent();
-                try ais.maybeInsertNewline();
+            var i = datas[node].lhs;
+            while (i <= datas[node].rhs) : (i += 1) try renderToken(ais, tree, i, .newline);
 
-                var i = datas[node].lhs;
-                while (i <= datas[node].rhs) : (i += 1) try renderToken(ais, tree, i, .newline);
+            while (locked_indents > 0) : (locked_indents -= 1) ais.popIndent();
 
-                while (locked_indents > 0) : (locked_indents -= 1) ais.popIndent();
-
-                switch (space) {
-                    .none => {},
-                    .semicolon => if (token_tags[i] == .semicolon) try renderToken(ais, tree, i, .newline),
-                    .comma => if (token_tags[i] == .comma) try renderToken(ais, tree, i, .newline),
-                    .comma_space => if (token_tags[i] == .comma) try renderToken(ais, tree, i, .space),
-                    else => unreachable,
-                }
-            },
-            else => unreachable,
+            switch (space) {
+                .none => {},
+                .semicolon => if (token_tags[i] == .semicolon) try renderToken(ais, tree, i, .newline),
+                .comma => if (token_tags[i] == .comma) try renderToken(ais, tree, i, .newline),
+                .comma_space => if (token_tags[i] == .comma) try renderToken(ais, tree, i, .space),
+                else => unreachable,
+            }
         },
 
         .error_value => {
@@ -1850,8 +1846,7 @@ fn renderCall(
                 try renderExpression(ais, tree, param_node, Space.none);
 
                 // Unindent the comma for multiline string literals
-                const is_multiline_string = node_tags[param_node] == .string_literal and
-                    token_tags[main_tokens[param_node]] == .multiline_string_literal_line;
+                const is_multiline_string = node_tags[param_node] == .multiline_string_literal;
                 if (is_multiline_string) ais.popIndent();
 
                 const comma = tree.lastToken(param_node) + 1;