Handle bare 'raise' statements

Previously, a non-satisfied except filter would cause the traceback
to be lost, since we were using the one-argument 'raise exc' form.

src/codegen/irgen/irgenerator.cpp

@@ -1730,15 +1730,21 @@ private:
     }
 
     void doRaise(AST_Raise* node, ExcInfo exc_info) {
-        RELEASE_ASSERT(node->arg0 != NULL, "");
+        std::vector<llvm::Value*> args;
+        llvm::Value* raise_func = g.funcs.raise0;
+
+        if (node->arg0) {
+            raise_func = g.funcs.raise1;
+
+            CompilerVariable* arg0 = evalExpr(node->arg0, exc_info);
+            ConcreteCompilerVariable* converted_arg0 = arg0->makeConverted(emitter, arg0->getBoxType());
+            arg0->decvref(emitter);
+            args.push_back(converted_arg0->getValue());
+        }
         RELEASE_ASSERT(node->arg1 == NULL, "");
         RELEASE_ASSERT(node->arg2 == NULL, "");
 
-        CompilerVariable* arg0 = evalExpr(node->arg0, exc_info);
-        ConcreteCompilerVariable* converted_arg0 = arg0->makeConverted(emitter, arg0->getBoxType());
-        arg0->decvref(emitter);
-
-        emitter.createCall(exc_info, g.funcs.raise1, { converted_arg0->getValue() });
+        emitter.createCall(exc_info, raise_func, args);
         emitter.getBuilder()->CreateUnreachable();
 
         endBlock(DEAD);

src/codegen/runtime_hooks.cpp

@@ -219,6 +219,7 @@ void initGlobalFuncs(GlobalState& g) {
 
     GET(__cxa_begin_catch);
     g.funcs.__cxa_end_catch = addFunc((void*)__cxa_end_catch, g.void_);
+    GET(raise0);
     GET(raise1);
 
     g.funcs.div_i64_i64 = getFunc((void*)div_i64_i64, "div_i64_i64");

src/codegen/runtime_hooks.h

@@ -44,7 +44,7 @@ struct GlobalFuncs {
     llvm::Value* reoptCompiledFunc, *compilePartialFunc;
 
     llvm::Value* __cxa_begin_catch, *__cxa_end_catch;
-    llvm::Value* raise1;
+    llvm::Value* raise0, *raise1;
 
     llvm::Value* div_i64_i64, *mod_i64_i64, *pow_i64_i64;
     llvm::Value* div_float_float, *mod_float_float, *pow_float_float;

src/core/cfg.cpp

@@ -1530,7 +1530,6 @@ public:
 
             if (!caught_all) {
                 AST_Raise* raise = new AST_Raise();
-                raise->arg0 = exc_obj;
                 push_back(raise);
                 curblock->push_back(new AST_Unreachable());
                 curblock = NULL;

src/gc/collector.cpp

@@ -42,6 +42,18 @@ void registerStaticRootObj(void* obj) {
     roots.push(obj);
 }
 
+static std::unordered_set<StaticRootHandle*>* getRootHandles() {
+    static std::unordered_set<StaticRootHandle*> root_handles;
+    return &root_handles;
+}
+
+StaticRootHandle::StaticRootHandle() {
+    getRootHandles()->insert(this);
+}
+StaticRootHandle::~StaticRootHandle() {
+    getRootHandles()->erase(this);
+}
+
 bool TraceStackGCVisitor::isValid(void* p) {
     return global_heap.getAllocationFromInteriorPointer(p);
 }
@@ -105,6 +117,10 @@ static void markPhase() {
 
     TraceStackGCVisitor visitor(&stack);
 
+    for (auto h : *getRootHandles()) {
+        visitor.visitPotential(h->value);
+    }
+
     // if (VERBOSITY()) printf("Found %d roots\n", stack.size());
     while (void* p = stack.pop()) {
         assert(((intptr_t)p) % 8 == 0);

src/gc/collector.h

@@ -83,6 +83,19 @@ public:
 // (that should be registerStaticRootPtr)
 void registerStaticRootObj(void* root_obj);
 void runCollection();
+
+// If you want to have a static root "location" where multiple values could be stored, use this:
+class StaticRootHandle {
+public:
+    Box* value;
+
+    StaticRootHandle();
+    ~StaticRootHandle();
+
+    void operator=(Box* b) { value = b; }
+
+    operator Box*() { return value; }
+};
 }
 }
 

src/runtime/builtin_modules/posix.cpp

+// Copyright (c) 2014 Dropbox, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <cmath>
+
+#include "core/types.h"
+#include "gc/collector.h"
+#include "runtime/gc_runtime.h"
+#include "runtime/inline/boxing.h"
+#include "runtime/types.h"
+#include "runtime/util.h"
+
+namespace pyston {
+
+BoxedModule* posix_module;
+
+void setupPosix() {
+    posix_module = createModule("posix", "__builtin__");
+}
+}

src/runtime/inline/link_forcer.cpp

@@ -90,6 +90,7 @@ void force() {
     FORCE(runtimeCall);
     FORCE(callattr);
 
+    FORCE(raise0);
     FORCE(raise1);
 
     FORCE(div_i64_i64);

src/runtime/objmodel.h

@@ -28,7 +28,8 @@ class BoxedInt;
 class BoxedList;
 class BoxedString;
 
-// user-level raise function that implements some python-level semantics
+// user-level raise functions that implement python-level semantics
+extern "C" void raise0() __attribute__((__noreturn__));
 extern "C" void raise1(Box*) __attribute__((__noreturn__));
 extern "C" void raise2(Box*, Box*) __attribute__((__noreturn__));
 extern "C" void raise3(Box*, Box*, Box*) __attribute__((__noreturn__));

src/runtime/stacktrace.cpp

@@ -20,6 +20,7 @@
 #include "codegen/codegen.h"
 #include "codegen/llvm_interpreter.h"
 #include "core/options.h"
+#include "gc/collector.h"
 #include "runtime/objmodel.h"
 #include "runtime/types.h"
 #include "runtime/util.h"
@@ -100,21 +101,25 @@ void unwindExc(Box* exc_obj) {
 }
 
 static std::vector<const LineInfo*> getTracebackEntries();
+static gc::StaticRootHandle last_exc;
 static std::vector<const LineInfo*> last_tb;
 
-void raiseExc(Box* exc_obj) __attribute__((__noreturn__));
-void raiseExc(Box* exc_obj) {
-    auto entries = getTracebackEntries();
-    last_tb = std::move(entries);
-
-
+void raiseRaw(Box* exc_obj) __attribute__((__noreturn__));
+void raiseRaw(Box* exc_obj) {
     // Using libgcc:
     throw exc_obj;
 
     // Using libunwind
     // unwindExc(exc_obj);
+}
 
-    abort();
+void raiseExc(Box* exc_obj) __attribute__((__noreturn__));
+void raiseExc(Box* exc_obj) {
+    auto entries = getTracebackEntries();
+    last_tb = std::move(entries);
+    last_exc = exc_obj;
+
+    raiseRaw(exc_obj);
 }
 
 void printLastTraceback() {
@@ -190,6 +195,10 @@ static std::vector<const LineInfo*> getTracebackEntries() {
     return entries;
 }
 
+void raise0() {
+    raiseRaw(last_exc);
+}
+
 void raise1(Box* b) {
     if (b->cls == type_cls) {
         BoxedClass* c = static_cast<BoxedClass*>(b);

src/runtime/types.cpp

@@ -599,9 +599,10 @@ void setupRuntime() {
 
     setupBuiltins();
     setupMath();
-    setupErrno();
     setupTime();
     setupThread();
+    setupErrno();
+    setupPosix();
 
     setupCAPI();
 

src/runtime/types.h

@@ -58,6 +58,7 @@ void setupMath();
 void setupTime();
 void setupThread();
 void setupErrno();
+void setupPosix();
 void setupSysEnd();
 
 BoxedDict* getSysModulesDict();