---

yaml
---
r: 138415
b: refs/heads/try2
c: 423843e
h: refs/heads/master
i:
  138413: a13de82
  138411: 9e2f3e7
  138407: e37c816
  138399: 0086df1
v: v3

Author: brson

[refs]

@@ -5,7 +5,7 @@ refs/heads/snap-stage3: 78a7676898d9f80ab540c6df5d4c9ce35bb50463
 refs/heads/try: 519addf6277dbafccbb4159db4b710c37eaa2ec5
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b
-refs/heads/try2: 62f2b4943a223ff7dc168d8fed5ebc50f34150db
+refs/heads/try2: 423843e54bdbd6e32a0a75b7502904458e20c480
 refs/heads/dist-snap: ba4081a5a8573875fed17545846f6f6902c8ba8d
 refs/tags/release-0.2: c870d2dffb391e14efb05aa27898f1f6333a9596
 refs/tags/release-0.3: b5f0d0f648d9a6153664837026ba1be43d3e2503

branches/try2/src/librustc/middle/trans/expr.rs

@@ -491,11 +491,29 @@ fn trans_rvalue_stmt_unadjusted(bcx: block, expr: @ast::expr) -> block {
         ast::expr_swap(dst, src) => {
             let dst_datum = unpack_datum!(bcx, trans_lvalue(bcx, dst));
             let src_datum = unpack_datum!(bcx, trans_lvalue(bcx, src));
-            let scratch = scratch_datum(bcx, dst_datum.ty, false);
 
-            let bcx = dst_datum.move_to_datum(bcx, INIT, scratch);
-            let bcx = src_datum.move_to_datum(bcx, INIT, dst_datum);
-            return scratch.move_to_datum(bcx, INIT, src_datum);
+            // If the source and destination are the same, then don't swap.
+            // Avoids performing an overlapping memcpy
+            let dst_datum_ref = dst_datum.to_ref_llval(bcx);
+            let src_datum_ref = src_datum.to_ref_llval(bcx);
+            let cmp = ICmp(bcx, lib::llvm::IntEQ,
+                           src_datum_ref,
+                           dst_datum_ref);
+
+            let swap_cx = base::sub_block(bcx, ~"swap");
+            let next_cx = base::sub_block(bcx, ~"next");
+
+            CondBr(bcx, cmp, next_cx.llbb, swap_cx.llbb);
+
+            let scratch = scratch_datum(swap_cx, dst_datum.ty, false);
+
+            let swap_cx = dst_datum.move_to_datum(swap_cx, INIT, scratch);
+            let swap_cx = src_datum.move_to_datum(swap_cx, INIT, dst_datum);
+            let swap_cx = scratch.move_to_datum(swap_cx, INIT, src_datum);
+
+            Br(swap_cx, next_cx.llbb);
+
+            return next_cx;
         }
         ast::expr_assign_op(op, dst, src) => {
             return trans_assign_op(bcx, expr, op, dst, src);

branches/try2/src/librustc/middle/ty.rs

@@ -2823,7 +2823,7 @@ pub pure fn ty_fn_ret(fty: t) -> t {
     }
 }
 
-pub fn is_fn_ty(fty: t) -> bool {
+fn is_fn_ty(fty: t) -> bool {
     match get(fty).sty {
         ty_bare_fn(_) => true,
         ty_closure(_) => true,

branches/try2/src/librustc/middle/typeck/check/_match.rs

@@ -92,7 +92,7 @@ pub fn check_pat_variant(pcx: pat_ctxt, pat: @ast::pat, path: @ast::path,
     match structure_of(pcx.fcx, pat.span, expected) {
         ty::ty_enum(_, ref expected_substs) => {
             // Lookup the enum and variant def ids:
-            let v_def = lookup_def(pcx.fcx, pat.span, pat.id);
+            let v_def = lookup_def(pcx.fcx, path.span, pat.id);
             let v_def_ids = ast_util::variant_def_ids(v_def);
 
             // Assign the pattern the type of the *enum*, not the variant.
@@ -125,17 +125,8 @@ pub fn check_pat_variant(pcx: pat_ctxt, pat: @ast::pat, path: @ast::path,
             kind_name = "variant";
         }
         ty::ty_struct(struct_def_id, ref expected_substs) => {
-            // Lookup the struct ctor def id
-            let s_def = lookup_def(pcx.fcx, pat.span, pat.id);
-            let s_def_id = ast_util::def_id_of_def(s_def);
-
             // Assign the pattern the type of the struct.
-            let ctor_tpt = ty::lookup_item_type(tcx, s_def_id);
-            let struct_tpt = if ty::is_fn_ty(ctor_tpt.ty) {
-                {ty: ty::ty_fn_ret(ctor_tpt.ty), ..ctor_tpt}
-            } else {
-                ctor_tpt
-            };
+            let struct_tpt = ty::lookup_item_type(tcx, struct_def_id);
             instantiate_path(pcx.fcx, path, struct_tpt, pat.span, pat.id,
                              pcx.block_region);
 

branches/try2/src/test/compile-fail/match-struct.rs

@@ -0,0 +1,45 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Issue #5041 - avoid overlapping memcpy when src and dest of a swap are the same
+
+pub fn main() {
+    let mut test = TestDescAndFn {
+        desc: TestDesc {
+            name: DynTestName(~"test"),
+            should_fail: false
+        },
+        testfn: DynTestFn(|| ()),
+    };
+    do_swap(&mut test);
+}
+
+fn do_swap(test: &mut TestDescAndFn) {
+    *test <-> *test;
+}
+
+pub enum TestName {
+    DynTestName(~str)
+}
+
+pub enum TestFn {
+    DynTestFn(~fn()),
+    DynBenchFn(~fn(&mut int))
+}
+
+pub struct TestDesc {
+    name: TestName,
+    should_fail: bool
+}
+
+pub struct TestDescAndFn {
+    desc: TestDesc,
+    testfn: TestFn,
+}