1 files changed, 106 insertions, 0 deletions
diff --git a/src/comp/middle/metadata.rs b/src/comp/middle/metadata.rs
index 433d7147..bff0ac94 100644
--- a/src/comp/middle/metadata.rs
+++ b/src/comp/middle/metadata.rs
@@ -1,12 +1,118 @@
 import std._str;
+import std._vec;
+import std.option;
+
 import front.ast;
 import middle.trans;
+import middle.ty;
 import back.x86;
+import util.common;
 
 import lib.llvm.llvm;
 import lib.llvm.llvm.ValueRef;
 import lib.llvm.False;
 
+// Type encoding
+
+// Compact string representation for ty.t values. API ty_str & parse_from_str.
+// (The second has to be authed pure.) Extra parameters are for converting
+// to/from def_ids in the string rep. Whatever format you choose should not
+// contain pipe characters.
+
+// Callback to translate defs to strs or back.
+type def_str = fn(ast.def_id) -> str;
+
+fn ty_str(@ty.t t, def_str ds) -> str {
+    ret sty_str(t.struct, ds);
+}
+
+fn sty_str(ty.sty st, def_str ds) -> str {
+    alt (st) {
+        case (ty.ty_nil) {ret "n";}
+        case (ty.ty_bool) {ret "b";}
+        case (ty.ty_int) {ret "i";}
+        case (ty.ty_uint) {ret "u";}
+        case (ty.ty_machine(?mach)) {
+            alt (mach) {
+                case (common.ty_u8) {ret "Mb";}
+                case (common.ty_u16) {ret "Mw";}
+                case (common.ty_u32) {ret "Ml";}
+                case (common.ty_u64) {ret "Md";}
+                case (common.ty_i8) {ret "MB";}
+                case (common.ty_i16) {ret "MW";}
+                case (common.ty_i32) {ret "ML";}
+                case (common.ty_i64) {ret "MD";}
+                case (common.ty_f32) {ret "Mf";}
+                case (common.ty_f64) {ret "MF";}
+            }
+        }
+        case (ty.ty_char) {ret "c";}
+        case (ty.ty_str) {ret "s";}
+        case (ty.ty_tag(?def,?tys)) { // TODO restore def_id
+            auto acc = "t[" + ds(def) + "|";
+            for (@ty.t t in tys) {acc += ty_str(t, ds);}
+            ret acc + "]";
+        }
+        case (ty.ty_box(?t)) {ret "@" + ty_str(t, ds);}
+        case (ty.ty_vec(?t)) {ret "V" + ty_str(t, ds);}
+        case (ty.ty_port(?t)) {ret "P" + ty_str(t, ds);}
+        case (ty.ty_chan(?t)) {ret "C" + ty_str(t, ds);}
+        case (ty.ty_tup(?tys)) {
+            auto acc = "T[";
+            for (@ty.t t in tys) {acc += ty_str(t, ds);}
+            ret acc + "]";
+        }
+        case (ty.ty_rec(?fields)) {
+            auto acc = "R[";
+            for (ty.field field in fields) {
+                acc += field.ident + "=";
+                acc += ty_str(field.ty, ds);
+            }
+            ret acc + "]";
+        }
+        case (ty.ty_fn(?proto,?args,?out)) {
+            ret proto_str(proto) + ty_fn_str(args, out, ds);
+        }
+        case (ty.ty_native_fn(?abi,?args,?out)) {
+            auto abistr;
+            alt (abi) {
+                case (ast.native_abi_rust) {abistr = "r";}
+                case (ast.native_abi_cdecl) {abistr = "c";}
+            }
+            ret "N" + abistr + ty_fn_str(args, out, ds);
+        }
+        case (ty.ty_obj(?methods)) {
+            auto acc = "O[";
+            for (ty.method m in methods) {
+                acc += proto_str(m.proto);
+                acc += m.ident;
+                acc += ty_fn_str(m.inputs, m.output, ds);
+            }
+            ret acc + "]";
+        }
+        case (ty.ty_var(?id)) {ret "X" + common.istr(id);}
+        case (ty.ty_native) {ret "E";}
+        // TODO (maybe?)   ty_param(ast.def_id), ty_type;
+    }
+}
+
+fn proto_str(ast.proto proto) -> str {
+    alt (proto) {
+        case (ast.proto_iter) {ret "W";}
+        case (ast.proto_fn) {ret "F";}
+    }
+}
+
+fn ty_fn_str(vec[ty.arg] args, @ty.t out, def_str ds) -> str {
+    auto acc = "[";
+    for (ty.arg arg in args) {
+        if (arg.mode == ast.alias) {acc += "&";}
+        acc += ty_str(arg.ty, ds);
+    }
+    ret acc + "]" + ty_str(out, ds);
+}
+
+
 // Returns a Plain Old LLVM String.
 fn C_postr(str s) -> ValueRef {
     ret llvm.LLVMConstString(_str.buf(s), _str.byte_len(s), False);