add pex

1 files changed, 38 insertions, 0 deletions

diff --git a/src/pex/optimizer/root.zig b/src/pex/optimizer/root.zig
new file mode 100644
index 0000000..68ce968
--- /dev/null
+++ b/src/pex/optimizer/root.zig
@@ -0,0 +1,38 @@
+const std = @import("std");
+const Block = @import("../block.zig");
+const Node = @import("../node.zig");
+const Rule = @import("../../rule.zig");
+
+pub fn optimize_block(
+    blocks: []Block,
+    raw: *Block,
+    target: *Block,
+    node_pool: *std.heap.MemoryPool(Node),
+    allocator: std.mem.Allocator,
+) !void {
+    target.* = try raw.clone(allocator, node_pool);
+    _ = blocks;
+
+    for (target.heads.items) |head| {
+        try hard_link_right_recursion(target, head);
+    }
+}
+
+pub fn hard_link_right_recursion(
+    block: *Block,
+    current: *Node,
+) !void {
+    switch (current.instruction) {
+        .call => |id| if (id == block.id) {
+            if (current.next.?.instruction == .@"return") {
+                current.instruction = .{ .jump = &block.heads };
+                return;
+            }
+        },
+        else => {},
+    }
+
+    if (current.next) |next| {
+        try hard_link_right_recursion(block, next);
+    }
+}