---

yaml
---
r: 64286
b: refs/heads/snap-stage3
c: dcd5d14
h: refs/heads/master
v: v3

Author: dotdash

[refs]

@@ -1,7 +1,7 @@
 ---
 refs/heads/master: 2d28d645422c1617be58c8ca7ad9a457264ca850
 refs/heads/snap-stage1: e33de59e47c5076a89eadeb38f4934f58a3618a6
-refs/heads/snap-stage3: a9eb86823049c2eff98e74fcac8ae75cc8760f33
+refs/heads/snap-stage3: dcd5d14e6cbb32aeccae3d12951181c525070ee7
 refs/heads/try: 7b78b52e602bb3ea8174f9b2006bff3315f03ef9
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b

branches/snap-stage3/src/librustc/middle/trans/base.rs

@@ -1102,11 +1102,6 @@ pub fn trans_trace(bcx: block, sp_opt: Option<span>, trace_str: @str) {
     Call(bcx, ccx.upcalls.trace, args);
 }
 
-pub fn build_return(bcx: block) {
-    let _icx = push_ctxt("build_return");
-    Br(bcx, bcx.fcx.llreturn);
-}
-
 pub fn ignore_lhs(_bcx: block, local: &ast::local) -> bool {
     match local.node.pat.node {
         ast::pat_wild => true, _ => false
@@ -1364,6 +1359,42 @@ pub fn cleanup_and_leave(bcx: block,
     }
 }
 
+pub fn cleanup_block(bcx: block, upto: Option<BasicBlockRef>) -> block{
+    let _icx = push_ctxt("cleanup_block");
+    let mut cur = bcx;
+    let mut bcx = bcx;
+    loop {
+        debug!("cleanup_block: %s", cur.to_str());
+
+        if bcx.sess().trace() {
+            trans_trace(
+                bcx, None,
+                (fmt!("cleanup_block(%s)", cur.to_str())).to_managed());
+        }
+
+        let mut cur_scope = cur.scope;
+        loop {
+            cur_scope = match cur_scope {
+                Some (inf) => {
+                    bcx = trans_block_cleanups_(bcx, inf.cleanups.to_owned(), false);
+                    inf.parent
+                }
+                None => break
+            }
+        }
+
+        match upto {
+          Some(bb) => { if cur.llbb == bb { break; } }
+          _ => ()
+        }
+        cur = match cur.parent {
+          Some(next) => next,
+          None => { assert!(upto.is_none()); break; }
+        };
+    }
+    bcx
+}
+
 pub fn cleanup_and_Br(bcx: block, upto: block, target: BasicBlockRef) {
     let _icx = push_ctxt("cleanup_and_Br");
     cleanup_and_leave(bcx, Some(upto.llbb), Some(target));
@@ -1544,7 +1575,6 @@ pub fn arrayalloca(cx: block, ty: Type, v: ValueRef) -> ValueRef {
 
 pub struct BasicBlocks {
     sa: BasicBlockRef,
-    rt: BasicBlockRef
 }
 
 // Creates the standard set of basic blocks for a function
@@ -1554,12 +1584,18 @@ pub fn mk_standard_basic_blocks(llfn: ValueRef) -> BasicBlocks {
         BasicBlocks {
             sa: str::as_c_str("static_allocas",
                            |buf| llvm::LLVMAppendBasicBlockInContext(cx, llfn, buf)),
-            rt: str::as_c_str("return",
-                           |buf| llvm::LLVMAppendBasicBlockInContext(cx, llfn, buf))
         }
     }
 }
 
+pub fn mk_return_basic_block(llfn: ValueRef) -> BasicBlockRef {
+    unsafe {
+        let cx = task_llcx();
+        str::as_c_str("return",
+                      |buf| llvm::LLVMAppendBasicBlockInContext(cx, llfn, buf))
+    }
+}
+
 // Creates and returns space for, or returns the argument representing, the
 // slot where the return value of the function must go.
 pub fn make_return_pointer(fcx: fn_ctxt, output_type: ty::t) -> ValueRef {
@@ -1613,7 +1649,7 @@ pub fn new_fn_ctxt_w_id(ccx: @mut CrateContext,
           llretptr: None,
           llstaticallocas: llbbs.sa,
           llloadenv: None,
-          llreturn: llbbs.rt,
+          llreturn: None,
           llself: None,
           personality: None,
           loop_ret: None,
@@ -1757,16 +1793,24 @@ pub fn copy_args_to_allocas(fcx: fn_ctxt,
 
 // Ties up the llstaticallocas -> llloadenv -> lltop edges,
 // and builds the return block.
-pub fn finish_fn(fcx: fn_ctxt, lltop: BasicBlockRef) {
+pub fn finish_fn(fcx: fn_ctxt, lltop: BasicBlockRef, last_bcx: block) {
     let _icx = push_ctxt("finish_fn");
     tie_up_header_blocks(fcx, lltop);
-    build_return_block(fcx);
+
+    let ret_cx = match fcx.llreturn {
+        Some(llreturn) => {
+            if !last_bcx.terminated {
+                Br(last_bcx, llreturn);
+            }
+            raw_block(fcx, false, llreturn)
+        }
+        None => last_bcx
+    };
+    build_return_block(fcx, ret_cx);
 }
 
 // Builds the return block for a function.
-pub fn build_return_block(fcx: fn_ctxt) {
-    let ret_cx = raw_block(fcx, false, fcx.llreturn);
-
+pub fn build_return_block(fcx: fn_ctxt, ret_cx: block) {
     // Return the value if this function immediate; otherwise, return void.
     if fcx.llretptr.is_some() && fcx.has_immediate_return_value {
         Ret(ret_cx, Load(ret_cx, fcx.llretptr.get()))
@@ -1854,16 +1898,21 @@ pub fn trans_closure(ccx: @mut CrateContext,
     }
 
     finish(bcx);
-    cleanup_and_Br(bcx, bcx_top, fcx.llreturn);
+    match fcx.llreturn {
+        Some(llreturn) => cleanup_and_Br(bcx, bcx_top, llreturn),
+        None => bcx = cleanup_block(bcx, Some(bcx_top.llbb))
+    };
 
     // Put return block after all other blocks.
     // This somewhat improves single-stepping experience in debugger.
     unsafe {
-        llvm::LLVMMoveBasicBlockAfter(fcx.llreturn, bcx.llbb);
+        for fcx.llreturn.iter().advance |&llreturn| {
+            llvm::LLVMMoveBasicBlockAfter(llreturn, bcx.llbb);
+        }
     }
 
     // Insert the mandatory first few basic blocks before lltop.
-    finish_fn(fcx, lltop);
+    finish_fn(fcx, lltop, bcx);
 }
 
 // trans_fn: creates an LLVM function corresponding to a source language
@@ -2046,8 +2095,7 @@ pub fn trans_enum_variant_or_tuple_like_struct<A:IdAndTy>(
         let arg_ty = arg_tys[i];
         memcpy_ty(bcx, lldestptr, llarg, arg_ty);
     }
-    build_return(bcx);
-    finish_fn(fcx, lltop);
+    finish_fn(fcx, lltop, bcx);
 }
 
 pub fn trans_enum_def(ccx: @mut CrateContext, enum_definition: &ast::enum_def,
@@ -2288,8 +2336,7 @@ pub fn create_entry_wrapper(ccx: @mut CrateContext,
         let args = ~[llenvarg];
         Call(bcx, main_llfn, args);
 
-        build_return(bcx);
-        finish_fn(fcx, lltop);
+        finish_fn(fcx, lltop, bcx);
         return llfdecl;
     }
 

branches/snap-stage3/src/librustc/middle/trans/callee.rs

@@ -704,7 +704,7 @@ pub fn trans_call_inner(in_cx: block,
                         Store(bcx, C_bool(false), bcx.fcx.llretptr.get());
                     }
                 }
-                base::cleanup_and_leave(bcx, None, Some(bcx.fcx.llreturn));
+                base::cleanup_and_leave(bcx, None, Some(bcx.fcx.get_llreturn()));
                 Unreachable(bcx);
                 bcx
             }

branches/snap-stage3/src/librustc/middle/trans/common.rs

@@ -184,7 +184,7 @@ pub struct fn_ctxt_ {
     // (LLVM requires that arguments be copied to local allocas before
     // allowing most any operation to be performed on them.)
     llloadenv: Option<BasicBlockRef>,
-    llreturn: BasicBlockRef,
+    llreturn: Option<BasicBlockRef>,
     // The 'self' value currently in use in this function, if there
     // is one.
     //
@@ -251,6 +251,13 @@ impl fn_ctxt_ {
         }
     }
 
+    pub fn get_llreturn(&mut self) -> BasicBlockRef {
+        if self.llreturn.is_none() {
+            self.llreturn = Some(base::mk_return_basic_block(self.llfn));
+        }
+
+        self.llreturn.get()
+    }
 }
 
 pub type fn_ctxt = @mut fn_ctxt_;

branches/snap-stage3/src/librustc/middle/trans/controlflow.rs

@@ -279,7 +279,7 @@ pub fn trans_break_cont(bcx: block,
                         // This is a return from a loop body block
                         None => {
                             Store(bcx, C_bool(!to_end), bcx.fcx.llretptr.get());
-                            cleanup_and_leave(bcx, None, Some(bcx.fcx.llreturn));
+                            cleanup_and_leave(bcx, None, Some(bcx.fcx.get_llreturn()));
                             Unreachable(bcx);
                             return bcx;
                         }
@@ -328,7 +328,7 @@ pub fn trans_ret(bcx: block, e: Option<@ast::expr>) -> block {
       }
       _ => ()
     }
-    cleanup_and_leave(bcx, None, Some(bcx.fcx.llreturn));
+    cleanup_and_leave(bcx, None, Some(bcx.fcx.get_llreturn()));
     Unreachable(bcx);
     return bcx;
 }

branches/snap-stage3/src/librustc/middle/trans/foreign.rs

@@ -164,7 +164,10 @@ fn build_shim_fn_(ccx: @mut CrateContext,
     // follow the normal Rust calling conventions.
     tie_up_header_blocks(fcx, lltop);
 
-    let ret_cx = raw_block(fcx, false, fcx.llreturn);
+    let ret_cx = match fcx.llreturn {
+        Some(llreturn) => raw_block(fcx, false, llreturn),
+        None => bcx
+    };
     RetVoid(ret_cx);
 
     return llshimfn;
@@ -217,7 +220,10 @@ fn build_wrap_fn_(ccx: @mut CrateContext,
     tie_up_header_blocks(fcx, lltop);
 
     // Then return according to the C ABI.
-    let return_context = raw_block(fcx, false, fcx.llreturn);
+    let return_context = match fcx.llreturn {
+        Some(llreturn) => raw_block(fcx, false, llreturn),
+        None => bcx
+    };
 
     let llfunctiontype = val_ty(llwrapfn);
     let llfunctiontype = llfunctiontype.element_type();
@@ -388,7 +394,6 @@ pub fn trans_foreign_mod(ccx: @mut CrateContext,
                                      tys.ret_def,
                                      llargbundle,
                                      llretval);
-            build_return(bcx);
         }
 
         let lname = link_name(ccx, foreign_item);
@@ -438,8 +443,7 @@ pub fn trans_foreign_mod(ccx: @mut CrateContext,
         if !ty::type_is_nil(ret_ty) && !ty::type_is_bot(ret_ty) {
             Store(bcx, retval, fcx.llretptr.get());
         }
-        build_return(bcx);
-        finish_fn(fcx, lltop);
+        finish_fn(fcx, lltop, bcx);
     }
 
     // FIXME (#2535): this is very shaky and probably gets ABIs wrong all
@@ -467,8 +471,7 @@ pub fn trans_foreign_mod(ccx: @mut CrateContext,
         if !ty::type_is_nil(ret_ty) && !ty::type_is_bot(ret_ty) {
             Store(bcx, retval, fcx.llretptr.get());
         }
-        build_return(bcx);
-        finish_fn(fcx, lltop);
+        finish_fn(fcx, lltop, bcx);
     }
 
     fn build_wrap_fn(ccx: @mut CrateContext,
@@ -534,7 +537,6 @@ pub fn trans_foreign_mod(ccx: @mut CrateContext,
                 let llretptr = load_inbounds(bcx, llargbundle, [0, arg_count]);
                 Store(bcx, Load(bcx, llretptr), retptr);
             }
-            build_return(bcx);
         }
     }
 }
@@ -629,8 +631,7 @@ pub fn trans_intrinsic(ccx: @mut CrateContext,
             }
         }
 
-        build_return(bcx);
-        finish_fn(fcx, lltop);
+        finish_fn(fcx, lltop, bcx);
 
         return;
     }
@@ -1124,8 +1125,7 @@ pub fn trans_intrinsic(ccx: @mut CrateContext,
             ccx.sess.span_bug(item.span, "unknown intrinsic");
         }
     }
-    build_return(bcx);
-    finish_fn(fcx, lltop);
+    finish_fn(fcx, lltop, bcx);
 }
 
 /**
@@ -1257,8 +1257,6 @@ pub fn trans_foreign_fn(ccx: @mut CrateContext,
                 // NB: The return pointer in the Rust ABI function is wired
                 // directly into the return slot in the shim struct.
             }
-
-            build_return(bcx);
         }
 
         let shim_name = link::mangle_internal_name_by_path(
@@ -1314,7 +1312,6 @@ pub fn trans_foreign_fn(ccx: @mut CrateContext,
         fn build_ret(bcx: block, tys: &ShimTypes, llargbundle: ValueRef) {
             let _icx = push_ctxt("foreign::foreign::wrap::build_ret");
             tys.fn_ty.build_wrap_ret(bcx, tys.llsig.llarg_tys, llargbundle);
-            build_return(bcx);
         }
     }