Accept main(args: [str]) as main signature

src/comp/middle/trans.rs

@@ -6345,28 +6345,153 @@ fn decl_fn_and_pair_full(ccx: &@crate_ctxt, sp: &span, path: &[str],
       }
       _ { ccx.sess.bug("decl_fn_and_pair(): fn item doesn't have fn type!"); }
     }
-    let is_main: bool = is_main_name(path) && !ccx.sess.get_opts().library;
-    // Declare the function itself.
 
-    let s: str =
-        if is_main {
-            "_rust_main"
-        } else { mangle_internal_name_by_path(ccx, path) };
+    let s: str =  mangle_internal_name_by_path(ccx, path);
     let llfn: ValueRef = decl_internal_fastcall_fn(ccx.llmod, s, llfty);
     // Declare the global constant pair that points to it.
 
     let ps: str = mangle_exported_name(ccx, path, node_type);
     register_fn_pair(ccx, ps, llfty, llfn, node_id);
+
+    let is_main: bool = is_main_name(path) && !ccx.sess.get_opts().library;
     if is_main {
-        if ccx.main_fn != none[ValueRef] {
-            ccx.sess.span_fatal(sp, "multiple 'main' functions");
-        }
-        llvm::LLVMSetLinkage(llfn,
-                             lib::llvm::LLVMExternalLinkage as llvm::Linkage);
-        ccx.main_fn = some(llfn);
+        create_main_wrapper(ccx, sp, llfn, node_type);
     }
 }
 
+fn create_main_wrapper(ccx: &@crate_ctxt, sp: &span,
+                       main_llfn: ValueRef, main_node_type: ty::t) {
+
+    if ccx.main_fn != none[ValueRef] {
+        ccx.sess.span_fatal(sp, "multiple 'main' functions");
+    }
+
+    tag main_mode {
+        mm_nil;
+        mm_vec;
+        mm_ivec;
+    };
+
+    let main_mode = alt ty::struct(ccx.tcx, main_node_type) {
+      ty::ty_fn(_, args, _ ,_ ,_) {
+        if std::ivec::len(args) == 0u {
+            mm_nil
+        } else {
+            alt ty::struct(ccx.tcx, args.(0).ty) {
+              ty::ty_ivec(_) { mm_ivec }
+              ty::ty_vec(_) { mm_vec }
+            }
+        }
+      }
+    };
+
+    // Have to create two different main functions depending on whether
+    // main was declared to take vec or ivec
+    let llfn_vec = create_main_wrapper_vec(ccx, sp, main_llfn, main_mode);
+    let llfn_ivec = create_main_wrapper_ivec(ccx, sp, main_llfn, main_mode);
+    let takes_ivec = main_mode == mm_ivec;
+    // Create a global to tell main.ll which main we want to use
+    create_main_type_indicator(ccx, takes_ivec);
+    ccx.main_fn = takes_ivec ? some(llfn_ivec) : some(llfn_vec);
+
+    fn create_main_wrapper_vec(ccx: &@crate_ctxt,
+                               sp: &span,
+                               main_llfn: ValueRef,
+                               main_mode: main_mode) -> ValueRef {
+
+        let vecarg = {
+            mode: ty::mo_val,
+            ty: ty::mk_vec(ccx.tcx, {
+                ty: ty::mk_str(ccx.tcx),
+                mut: ast::imm
+            })
+        };
+        let llfty = type_of_fn(ccx, sp,
+                               ast::proto_fn,
+                               ~[vecarg],
+                               ty::mk_nil(ccx.tcx),
+                               0u);
+        let llfdecl = decl_fastcall_fn(ccx.llmod, "_rust_main", llfty);
+
+        let fcx = new_fn_ctxt(new_local_ctxt(ccx), sp, llfdecl);
+        let bcx = new_top_block_ctxt(fcx);
+
+        if main_mode != mm_ivec {
+            let lloutputarg = llvm::LLVMGetParam(llfdecl, 0u);
+            let lltaskarg = llvm::LLVMGetParam(llfdecl, 1u);
+            let llenvarg = llvm::LLVMGetParam(llfdecl, 2u);
+            let llargvarg = llvm::LLVMGetParam(llfdecl, 3u);
+            let args = alt main_mode {
+              mm_nil. { ~[lloutputarg,
+                          lltaskarg,
+                          llenvarg] }
+              mm_vec. { ~[lloutputarg,
+                          lltaskarg,
+                          llenvarg,
+                          llargvarg] }
+            };
+            bcx.build.FastCall(main_llfn, args);
+        }
+        bcx.build.RetVoid();
+
+        let lltop = bcx.llbb;
+        finish_fn(fcx, lltop);
+
+        ret llfdecl;
+    }
+
+    fn create_main_wrapper_ivec(ccx: &@crate_ctxt,
+                                sp: &span,
+                                main_llfn: ValueRef,
+                                main_mode: main_mode) -> ValueRef {
+        let ivecarg = {
+            mode: ty::mo_val,
+            ty: ty::mk_ivec(ccx.tcx, {
+                ty: ty::mk_str(ccx.tcx),
+                mut: ast::imm
+            })
+        };
+        let llfty = type_of_fn(ccx, sp,
+                               ast::proto_fn,
+                               ~[ivecarg],
+                               ty::mk_nil(ccx.tcx),
+                               0u);
+        let llfdecl = decl_fastcall_fn(ccx.llmod, "_rust_main_ivec", llfty);
+
+        let fcx = new_fn_ctxt(new_local_ctxt(ccx), sp, llfdecl);
+        let bcx = new_top_block_ctxt(fcx);
+
+        if main_mode == mm_ivec {
+            let lloutputarg = llvm::LLVMGetParam(llfdecl, 0u);
+            let lltaskarg = llvm::LLVMGetParam(llfdecl, 1u);
+            let llenvarg = llvm::LLVMGetParam(llfdecl, 2u);
+            let llargvarg = llvm::LLVMGetParam(llfdecl, 3u);
+            let args = ~[lloutputarg,
+                         lltaskarg,
+                         llenvarg,
+                         llargvarg];
+            bcx.build.FastCall(main_llfn, args);
+        }
+        bcx.build.RetVoid();
+
+        let lltop = bcx.llbb;
+        finish_fn(fcx, lltop);
+
+        ret llfdecl;
+    }
+
+    // FIXME: Remove after main takes only ivec
+    // Sets a global value hinting to the runtime whether main takes
+    // a vec or an ivec
+    fn create_main_type_indicator(ccx: &@crate_ctxt, takes_ivec: bool) {
+        let i = llvm::LLVMAddGlobal(ccx.llmod, T_int(),
+                                    str::buf("_rust_main_is_ivec"));
+        llvm::LLVMSetInitializer(i, C_int(takes_ivec as int));
+        llvm::LLVMSetGlobalConstant(i, True);
+    }
+}
+
+
 // Create a closure: a pair containing (1) a ValueRef, pointing to where the
 // fn's definition is in the executable we're creating, and (2) a pointer to
 // space for the function's environment.

src/comp/middle/typeck.rs

@@ -2715,6 +2715,7 @@ fn check_item(ccx: @crate_ctxt, it: &@ast::item) {
 
 fn arg_is_argv_ty(tcx: &ty::ctxt, a: &ty::arg) -> bool {
     alt ty::struct(tcx, a.ty) {
+      // FIXME: Remove after main takes only ivec
       ty::ty_vec(mt) {
         if mt.mut != ast::imm { ret false; }
         alt ty::struct(tcx, mt.ty) {
@@ -2722,6 +2723,13 @@ fn arg_is_argv_ty(tcx: &ty::ctxt, a: &ty::arg) -> bool {
           _ { ret false; }
         }
       }
+      ty::ty_ivec(mt) {
+        if mt.mut != ast::imm { ret false; }
+        alt ty::struct(tcx, mt.ty) {
+          ty::ty_str. { ret true; }
+          _ { ret false; }
+        }
+      }
       _ { ret false; }
     }
 }

src/rt/main.ll.in

@@ -6,23 +6,48 @@
 %5 = type { i32, i32, i32, i32, [0 x %6*] }
 %6 = type { i32, i32, i32, i32, [0 x i8] }
 
-
-@_rust_crate_map_toplevel = external global %0
-
-declare fastcc void @_rust_main(i1* nocapture, %task*, %2* nocapture, %5*);
-declare i32 @rust_start(i32, i32, i32, i32)
-
 %tydesc = type { %tydesc**, i32, i32, void (i1*, %task*, i1*, %tydesc**, i8*)*, void (i1*, %task*, i1*, %tydesc**, i8*)*, void (i1*, %task*, i1*, %tydesc**, i8*)*, void (i1*, %task*, i1*, %tydesc**, i8*)*, void (i1*, %task*, i1*, %tydesc**, i8*)*, void (i1*, %task*, i1*, %tydesc**, i8*)*, void (i1*, %task*, i1*, %tydesc**, i8*)*, void (i1*, %task*, i1*, %tydesc**, i8*, i8*, i8)* }
 
 %task = type { i32, i32, i32, i32, i32, i32, i32, i32 }
 
+%ivec = type { i32, i32, [4 x { i32, i32, i32, i32, [0 x i8] }*] }
+
+@_rust_crate_map_toplevel = external global %0
+
+; FIXME: Remove after main takes only ivec
+@_rust_main_is_ivec = external global i32
+
+declare i32 @rust_start(i32, i32, i32, i32)
+
+declare external fastcc void @_rust_main(i1* nocapture, %task*, %2* nocapture, %5*);
+
 define void @_rust_main_wrap(i1* nocapture, %task *, %2* nocapture, %5 *)
 {
   tail call fastcc void @_rust_main(i1* %0, %task *%1, %2* nocapture %2, %5 *%3)
   ret void
 }
 
+declare i32 @rust_start_ivec(i32, i32, i32, i32, i32)
+
+declare external fastcc void @_rust_main_ivec(i1* nocapture, %task*, %2* nocapture, %ivec)
+
+define void @_rust_main_wrap_ivec(i1* nocapture, %task *, %2* nocapture, %ivec *)
+{
+  %ivec = load %ivec *%3
+  tail call fastcc void @_rust_main_ivec(i1* %0, %task *%1, %2* nocapture %2, %ivec %ivec)
+  ret void
+}
+
 define i32 @"MAIN"(i32, i32) {
+  %is_ivec = load i32 *@_rust_main_is_ivec
+  %is_ivec1 = trunc i32 %is_ivec to i1
+  br i1 %is_ivec1, label %ivec, label %evec
+
+evec:
   %3 = tail call i32 @rust_start(i32 ptrtoint (void (i1*, %task*, %2*, %5*)* @_rust_main_wrap to i32), i32 %0, i32 %1, i32 ptrtoint (%0* @_rust_crate_map_toplevel to i32))
   ret i32 %3
+
+ivec:
+  %4 = tail call i32 @rust_start_ivec(i32 ptrtoint (void (i1*, %task*, %2*, %ivec*)* @_rust_main_wrap_ivec to i32), i32 %0, i32 %1, i32 ptrtoint (%0* @_rust_crate_map_toplevel to i32), i32 %is_ivec)
+  ret i32 %4
 }

src/rt/rust.cpp

@@ -10,10 +10,12 @@ command_line_args : public kernel_owned<command_line_args>
 
     // vec[str] passed to rust_task::start.
     rust_vec *args;
+    rust_ivec *args_ivec;
 
     command_line_args(rust_task *task,
                       int sys_argc,
-                      char **sys_argv)
+                      char **sys_argv,
+                      bool main_is_ivec)
         : kernel(task->kernel),
           task(task),
           argc(sys_argc),
@@ -49,15 +51,39 @@ command_line_args : public kernel_owned<command_line_args>
             mem = kernel->malloc(str_alloc, "command line arg");
             strs[i] = new (mem) rust_str(str_alloc, str_fill,
                                          (uint8_t const *)argv[i]);
+            strs[i]->ref_count++;
         }
         args->fill = vec_fill;
         // If the caller has a declared args array, they may drop; but
         // we don't know if they have such an array. So we pin the args
         // array here to ensure it survives to program-shutdown.
         args->ref();
+
+        if (main_is_ivec) {
+            size_t ivec_interior_sz =
+                sizeof(size_t) * 2 + sizeof(rust_str *) * 4;
+            args_ivec = (rust_ivec *)
+                kernel->malloc(ivec_interior_sz,
+                               "command line arg interior");
+            args_ivec->fill = 0;
+            size_t ivec_exterior_sz = sizeof(rust_str *) * argc;
+            args_ivec->alloc = ivec_exterior_sz;
+            // NB: This is freed by some ivec machinery, probably the drop
+            // glue in main, so we don't free it ourselves
+            args_ivec->payload.ptr = (rust_ivec_heap *)
+                kernel->malloc(ivec_exterior_sz + sizeof(size_t),
+                               "command line arg exterior");
+            args_ivec->payload.ptr->fill = ivec_exterior_sz;
+            memcpy(&args_ivec->payload.ptr->data, strs, ivec_exterior_sz);
+        } else {
+            args_ivec = NULL;
+        }
     }
 
     ~command_line_args() {
+        if (args_ivec) {
+            kernel->free(args_ivec);
+        }
         if (args) {
             // Drop the args we've had pinned here.
             rust_str **strs = (rust_str**) &args->data[0];
@@ -84,7 +110,8 @@ command_line_args : public kernel_owned<command_line_args>
 int check_claims = 0;
 
 extern "C" CDECL int
-rust_start(uintptr_t main_fn, int argc, char **argv, void* crate_map) {
+rust_start_ivec(uintptr_t main_fn, int argc, char **argv,
+                void* crate_map, int main_is_ivec) {
 
     rust_env *env = load_env();
 
@@ -99,7 +126,7 @@ rust_start(uintptr_t main_fn, int argc, char **argv, void* crate_map) {
     rust_scheduler *sched = root_task->sched;
     command_line_args *args
         = new (kernel, "main command line args")
-        command_line_args(root_task, argc, argv);
+        command_line_args(root_task, argc, argv, main_is_ivec);
 
     DLOG(sched, dom, "startup: %d args in 0x%" PRIxPTR,
              args->argc, (uintptr_t)args->args);
@@ -107,7 +134,13 @@ rust_start(uintptr_t main_fn, int argc, char **argv, void* crate_map) {
         DLOG(sched, dom, "startup: arg[%d] = '%s'", i, args->argv[i]);
     }
 
-    root_task->start(main_fn, (uintptr_t)args->args);
+    if (main_is_ivec) {
+        DLOG(sched, dom, "main takes ivec");
+        root_task->start(main_fn, (uintptr_t)args->args_ivec);
+    } else {
+        DLOG(sched, dom, "main takes vec");
+        root_task->start(main_fn, (uintptr_t)args->args);
+    }
     root_task->deref();
     root_task = NULL;
 
@@ -127,6 +160,13 @@ rust_start(uintptr_t main_fn, int argc, char **argv, void* crate_map) {
     return ret;
 }
 
+extern "C" CDECL int
+rust_start(uintptr_t main_fn, int argc, char **argv,
+           void* crate_map) {
+    return rust_start_ivec(main_fn, argc, argv, crate_map, 0);
+}
+
+
 //
 // Local Variables:
 // mode: C++

src/rt/rustrt.def.in

@@ -62,6 +62,7 @@ rust_process_wait
 rust_ptr_eq
 rust_run_program
 rust_start
+rust_start_ivec
 rust_getcwd
 set_min_stack
 sched_threads

src/test/run-pass/main-ivec.rs

@@ -0,0 +1,3 @@
+fn main(args: [str]) {
+    for s in args { log s }
+}