Reproduce a JIT bug that virtualenv triggers

The issue is a difference between how PhiAnalysis and TypeAnalysis
handle OSR compilations: type analysis is osr-aware but phi analysis
isn't.  I think the right solution to this is to make phi and
definedness analysis also osr aware, but I want to get these other changes
in.

src/codegen/irgen/hooks.cpp

@@ -210,8 +210,8 @@ CompiledFunction* compileFunction(CLFunction* f, FunctionSpecialization* spec, E
             ss << ") -> ";
             ss << spec->rtn_type->debugName();
         } else {
-            ss << "\033[34;1mDoing OSR-entry partial compile of " << source->parent_module->fn << ":" << name << ", starting with backedge to block "
-               << entry_descriptor->backedge->target->idx;
+            ss << "\033[34;1mDoing OSR-entry partial compile of " << source->parent_module->fn << ":" << name
+               << ", starting with backedge to block " << entry_descriptor->backedge->target->idx;
         }
         ss << " at effort level " << (int)effort;
         ss << "\033[0m";

src/core/options.cpp

@@ -40,6 +40,7 @@ bool USE_STRIPPED_STDLIB = true; // always true
 bool ENABLE_INTERPRETER = true;
 bool ENABLE_PYPA_PARSER = true;
 bool USE_REGALLOC_BASIC = true;
+bool PAUSE_AT_ABORT = false;
 
 int OSR_THRESHOLD_INTERPRETER = 200;
 int REOPT_THRESHOLD_INTERPRETER = 100;

src/core/options.h

@@ -37,7 +37,7 @@ extern int OSR_THRESHOLD_T2, REOPT_THRESHOLD_T2;
 extern int SPECULATION_THRESHOLD;
 
 extern bool SHOW_DISASM, FORCE_INTERPRETER, FORCE_OPTIMIZE, PROFILE, DUMPJIT, TRAP, USE_STRIPPED_STDLIB,
-    CONTINUE_AFTER_FATAL, ENABLE_INTERPRETER, ENABLE_PYPA_PARSER, USE_REGALLOC_BASIC;
+    CONTINUE_AFTER_FATAL, ENABLE_INTERPRETER, ENABLE_PYPA_PARSER, USE_REGALLOC_BASIC, PAUSE_AT_ABORT;
 
 extern bool ENABLE_ICS, ENABLE_ICGENERICS, ENABLE_ICGETITEMS, ENABLE_ICSETITEMS, ENABLE_ICDELITEMS, ENABLE_ICBINEXPS,
     ENABLE_ICNONZEROS, ENABLE_ICCALLSITES, ENABLE_ICSETATTRS, ENABLE_ICGETATTRS, ENALBE_ICDELATTRS, ENABLE_ICGETGLOBALS,

src/jit.cpp

@@ -80,7 +80,7 @@ static int main(int argc, char** argv) {
     bool stats = false;
     bool unbuffered = false;
     const char* command = NULL;
-    while ((code = getopt(argc, argv, "+OqdIibpjtrsSvnxc:Fu")) != -1) {
+    while ((code = getopt(argc, argv, "+OqdIibpjtrsSvnxc:FuP")) != -1) {
         if (code == 'O')
             FORCE_OPTIMIZE = true;
         else if (code == 't')
@@ -113,6 +113,8 @@ static int main(int argc, char** argv) {
             USE_REGALLOC_BASIC = false;
         } else if (code == 'x') {
             ENABLE_PYPA_PARSER = false;
+        } else if (code == 'P') {
+            PAUSE_AT_ABORT = true;
         } else if (code == 'F') {
             CONTINUE_AFTER_FATAL = true;
         } else if (code == 'c') {

src/runtime/stacktrace.cpp

@@ -182,6 +182,12 @@ extern "C" void abort() {
         alarm(0);
     }
 
+    if (PAUSE_AT_ABORT) {
+        printf("PID %d about to call libc abort; pausing for a debugger...\n", getpid());
+        while (true) {
+            sleep(1);
+        }
+    }
     libc_abort();
     __builtin_unreachable();
 }

test/tests/osr_maybe_undefined3.py

+# expected: fail
+# - wip
+
+# Regression test: make sure we can handle variables that are only defined
+# on excluded parts of an osr compilation
+def f():
+    if True:
+        for i in xrange(20000):
+            pass
+    else:
+        a = 1
+f()
+
+def f2():
+    if True:
+        for i in xrange(20000):
+            pass
+    else:
+        a = 1
+
+    if False:
+        print a
+f2()