Construct new strings through upcalls.

Author: graydon

Diff for: src/rt/rust_upcall.cpp

@@ -291,6 +291,27 @@ upcall_shared_realloc(void *ptr, size_t size) {
 
 /**********************************************************************/
 
+struct s_str_new_args {
+    const char *cstr;
+    size_t len;
+    rust_str *retval;
+};
+
+extern "C" CDECL void
+upcall_s_str_new(s_str_new_args *args) {
+    rust_task *task = rust_get_current_task();
+    LOG_UPCALL_ENTRY(task);
+    args->retval = make_str(task->kernel, args->cstr, args->len, "str_new");
+}
+
+extern "C" CDECL rust_str*
+upcall_str_new(const char *cstr, size_t len) {
+    s_str_new_args args = { cstr, len, 0 };
+    UPCALL_SWITCH_STACK(&args, upcall_s_str_new);
+    return args.retval;
+}
+
+
 struct s_vec_grow_args {
     rust_vec** vp;
     size_t new_sz;

Diff for: src/rt/rustrt.def.in

@@ -69,6 +69,7 @@ upcall_shared_malloc
 upcall_shared_free
 upcall_shared_realloc
 upcall_vec_grow
+upcall_str_new
 upcall_str_concat
 upcall_call_shim_on_c_stack
 upcall_call_shim_on_rust_stack

Diff for: src/rustc/back/upcall.rs

@@ -17,6 +17,7 @@ type upcalls =
      shared_realloc: ValueRef,
      mark: ValueRef,
      vec_grow: ValueRef,
+     str_new: ValueRef,
      str_concat: ValueRef,
      cmp_type: ValueRef,
      log_type: ValueRef,
@@ -64,6 +65,8 @@ fn declare_upcalls(targ_cfg: @session::config,
               d("mark", [T_ptr(T_i8())], int_t),
           vec_grow:
               dv("vec_grow", [T_ptr(T_ptr(opaque_vec_t)), int_t]),
+          str_new:
+              d("str_new", [T_ptr(T_i8()), int_t], T_ptr(opaque_vec_t)),
           str_concat:
               d("str_concat", [T_ptr(opaque_vec_t), T_ptr(opaque_vec_t)],
                 T_ptr(opaque_vec_t)),

Diff for: src/rustc/middle/trans/tvec.rs

@@ -131,15 +131,11 @@ fn trans_vec(bcx: block, args: [@ast::expr], id: ast::node_id,
 
 fn trans_str(bcx: block, s: str, dest: dest) -> block {
     let _icx = bcx.insn_ctxt("tvec::trans_str");
-    let veclen = str::len(s) + 1u; // +1 for \0
-    let {bcx: bcx, val: sptr, _} =
-        alloc(bcx, ty::mk_str(bcx.tcx()), veclen);
-
     let ccx = bcx.ccx();
-    let llcstr = C_cstr(ccx, s);
-    call_memmove(bcx, get_dataptr(bcx, sptr, T_i8()), llcstr,
-                 C_uint(ccx, veclen));
-    ret base::store_in_dest(bcx, sptr, dest);
+    let cs = PointerCast(bcx, C_cstr(ccx, s), T_ptr(T_i8()));
+    let len = C_uint(ccx, str::len(s));
+    let n = Call(bcx, ccx.upcalls.str_new, [cs, len]);
+    ret base::store_in_dest(bcx, n, dest);
 }
 
 fn trans_append(bcx: block, vec_ty: ty::t, lhsptr: ValueRef,