Commit b336866fbc1edd4c999d3cd5d62ae7230d176fa7 | zig

author	Andrew Kelley <andrew@ziglang.org> 2023-05-29 15:30:56-07:00
committer	Andrew Kelley <andrew@ziglang.org> 2023-06-10 20:47:56-07:00
log	b336866fbc1edd4c999d3cd5d62ae7230d176fa7
tree	7c99d4d707c360c51fc56189b2393068144b626d
parent	804740af4ced8389e21df31a908c4212e32a477a

InternPool: avoid indexToKey recursion for ptr_elem,ptr_field

This is a hot function, and recursion makes it more difficult to
profile, as well as likely making it more difficult to optimize.

1 files changed, 24 insertions(+), 12 deletions(-)

src
- InternPool.zig

src/InternPool.zig+24-12

 @@ -2625,24 +2625,36 @@ pub fn indexToKey(ip: *const InternPool, index: Index) Key {
             } };
         },
         .ptr_elem => {
+            // Avoid `indexToKey` recursion by asserting the tag encoding.
             const info = ip.extraData(PtrBaseIndex, data);
-            return .{ .ptr = .{
+            const index_item = ip.items.get(@enumToInt(info.index));
-                .ty = info.ty,
+            return switch (index_item.tag) {
-                .addr = .{ .elem = .{
+                .int_usize => .{ .ptr = .{
-                    .base = info.base,
+                    .ty = info.ty,
-                    .index = ip.indexToKey(info.index).int.storage.u64,
+                    .addr = .{ .elem = .{
+                        .base = info.base,
+                        .index = index_item.data,
+                    } },
                 } },
-            } };
+                .int_positive => @panic("TODO"), // implement along with behavior test coverage
+                else => unreachable,
+            };
         },
         .ptr_field => {
+            // Avoid `indexToKey` recursion by asserting the tag encoding.
             const info = ip.extraData(PtrBaseIndex, data);
-            return .{ .ptr = .{
+            const index_item = ip.items.get(@enumToInt(info.index));
-                .ty = info.ty,
+            return switch (index_item.tag) {
-                .addr = .{ .field = .{
+                .int_usize => .{ .ptr = .{
-                    .base = info.base,
+                    .ty = info.ty,
-                    .index = ip.indexToKey(info.index).int.storage.u64,
+                    .addr = .{ .field = .{
+                        .base = info.base,
+                        .index = index_item.data,
+                    } },
                 } },
-            } };
+                .int_positive => @panic("TODO"), // implement along with behavior test coverage
+                else => unreachable,
+            };
         },
         .ptr_slice => {
             const info = ip.extraData(PtrSlice, data);