Adapt source position recording and fix ScopeIterator.

src/arm/full-codegen-arm.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 337 matching lines @@
 #ifdef DEBUG
     // Add a label for checking the size of the code used for returning.
     Label check_exit_codesize;
     masm_->bind(&check_exit_codesize);
 #endif
     // Make sure that the constant pool is not emitted inside of the return
     // sequence.
     { Assembler::BlockConstPoolScope block_const_pool(masm_);
       // Here we use masm_-> instead of the __ macro to avoid the code coverage
       // tool from instrumenting as we rely on the code size here.
-      int32_t sp_delta = (info_->scope()->num_parameters() + 1) * kPointerSize;
-      CodeGenerator::RecordPositions(masm_, function()->end_position() - 1);
+      Scope* scope = function()->scope();
+      int32_t sp_delta = (scope->num_parameters() + 1) * kPointerSize;
+      if (scope->is_function_scope()) {
+        // Set the source position of the return sequence to the position
+        // of the closing brace '}'.
+        CodeGenerator::RecordPositions(masm_, function()->end_position() - 1);

[Lasse Reichstein, 2011/11/21 10:16:40]

What if the function source doesn't have a closing brace, e.g., Function("return
42;") ?
Will this still work?

[Steven, 2011/11/24 13:23:31]

Søren and I came up with a different scheme when debug breaking in the return
sequence. In this case we don't use the source position anymore to learn about
the scopes. We simply return only the function scope but not any of the inner
catch/with/block scopes.

So for the ScopeIterator this hunk is not important anymore. I left it as it was
before and added test cases.
On 2011/11/21 10:16:40, Lasse Reichstein wrote:

+      } else {
+        ASSERT(scope->is_global_scope() || scope->is_eval_scope());
+        // Set the source position to one character past the source code, such
+        // that it definitely is not in the source code range of an immediate
+        // inner scope. For example in
+        //   eval('with ({x:1}) x = 1');
+        // the end position of the function generated for executing the eval code
+        // coincides with the end of the with scope which is the position of '1'.
+        CodeGenerator::RecordPositions(masm_, function()->end_position());
+      }
       __ RecordJSReturn();
       masm_->mov(sp, fp);
       masm_->ldm(ia_w, sp, fp.bit() | lr.bit());
       masm_->add(sp, sp, Operand(sp_delta));
       masm_->Jump(lr);
     }
 
 #ifdef DEBUG
     // Check that the size of the code used for returning is large enough
     // for the debugger's requirements.
@@ skipping 3987 matching lines @@
   *context_length = 0;
   return previous_;
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM