8206075: On x86, assert on unbound assembler Labels used as branch targets

8208480: Test failure: assert(is_bound() || is_unused()) after JDK-8206075 in C1
Summary: Combine unbound Label assertion checking backports
Reviewed-by: andrew, coffeys

src/cpu/x86/vm/interp_masm_x86_32.cpp

 /*
- * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -1445,5 +1445,7 @@ void InterpreterMacroAssembler::increment_mask_and_jump(Address counter_addr,
   incrementl(scratch, increment);
   movl(counter_addr, scratch);
   andl(scratch, mask);
-  jcc(cond, *where);
+  if (where != NULL) {
+    jcc(cond, *where);
+  }
 }

src/cpu/x86/vm/interp_masm_x86_64.cpp

 /*
- * Copyright (c) 2003, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -1505,5 +1505,7 @@ void InterpreterMacroAssembler::increment_mask_and_jump(Address counter_addr,
   incrementl(scratch, increment);
   movl(counter_addr, scratch);
   andl(scratch, mask);
-  jcc(cond, *where);
+  if (where != NULL) {
+    jcc(cond, *where);
+  }
 }

src/cpu/x86/vm/templateTable_x86_32.cpp

 /*
- * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -1640,15 +1640,16 @@ void TemplateTable::branch(bool is_jsr, bool is_wide) {
         // Increment the MDO backedge counter
         const Address mdo_backedge_counter(rbx, in_bytes(MethodData::backedge_counter_offset()) +
                                                 in_bytes(InvocationCounter::counter_offset()));
-        __ increment_mask_and_jump(mdo_backedge_counter, increment, mask,
-                                   rax, false, Assembler::zero, &backedge_counter_overflow);
+        __ increment_mask_and_jump(mdo_backedge_counter, increment, mask, rax, false, Assembler::zero,
+                                   UseOnStackReplacement ? &backedge_counter_overflow : NULL);
         __ jmp(dispatch);
       }
       __ bind(no_mdo);
       // Increment backedge counter in MethodCounters*
       __ movptr(rcx, Address(rcx, Method::method_counters_offset()));
       __ increment_mask_and_jump(Address(rcx, be_offset), increment, mask,
-                                 rax, false, Assembler::zero, &backedge_counter_overflow);
+                                 rax, false, Assembler::zero,
+                                 UseOnStackReplacement ? &backedge_counter_overflow : NULL);
     } else {
       // increment counter
       __ movptr(rcx, Address(rcx, Method::method_counters_offset()));

src/cpu/x86/vm/templateTable_x86_64.cpp

 /*
- * Copyright (c) 2003, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -1665,15 +1665,16 @@ void TemplateTable::branch(bool is_jsr, bool is_wide) {
         // Increment the MDO backedge counter
         const Address mdo_backedge_counter(rbx, in_bytes(MethodData::backedge_counter_offset()) +
                                            in_bytes(InvocationCounter::counter_offset()));
-        __ increment_mask_and_jump(mdo_backedge_counter, increment, mask,
-                                   rax, false, Assembler::zero, &backedge_counter_overflow);
+        __ increment_mask_and_jump(mdo_backedge_counter, increment, mask, rax, false, Assembler::zero,
+                                   UseOnStackReplacement ? &backedge_counter_overflow : NULL);
         __ jmp(dispatch);
       }
       __ bind(no_mdo);
       // Increment backedge counter in MethodCounters*
       __ movptr(rcx, Address(rcx, Method::method_counters_offset()));
       __ increment_mask_and_jump(Address(rcx, be_offset), increment, mask,
-                                 rax, false, Assembler::zero, &backedge_counter_overflow);
+                                 rax, false, Assembler::zero,
+                                 UseOnStackReplacement ? &backedge_counter_overflow : NULL);
     } else {
       // increment counter
       __ movptr(rcx, Address(rcx, Method::method_counters_offset()));

src/share/vm/asm/assembler.hpp

 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -169,6 +169,14 @@ class Label VALUE_OBJ_CLASS_SPEC {
   Label() {
     init();
   }
+
+  ~Label() {
+    assert(is_bound() || is_unused(), "Label was never bound to a location, but it was used as a jmp target");
+  }
+
+  void reset() {
+    init(); //leave _patch_overflow because it points to CodeBuffer.
+  }
 };
 
 // A union type for code which has to assemble both constant and

src/share/vm/c1/c1_LIRAssembler.cpp

 /*
- * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -128,6 +128,9 @@ LIR_Assembler::LIR_Assembler(Compilation* c):
 
 
 LIR_Assembler::~LIR_Assembler() {
+  // The unwind handler label may be unbound if this destructor is invoked because of a bail-out.
+  // Reset it here to avoid an assertion.
+  _unwind_handler_entry.reset();
 }