Store pc offset instead of absolute pc in the pc descriptors.

runtime/vm/debugger.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/debugger.h"
 
 #include "include/dart_api.h"
 
 #include "vm/code_generator.h"
 #include "vm/code_patcher.h"
@@ skipping 369 matching lines @@
 }
 
 
 // Compute token_pos_ and try_index_ and token_pos_initialized_.
 intptr_t ActivationFrame::TokenPos() {
   if (!token_pos_initialized_) {
     token_pos_initialized_ = true;
     token_pos_ = Scanner::kNoSourcePos;
     GetPcDescriptors();
     PcDescriptors::Iterator iter(pc_desc_, RawPcDescriptors::kAnyKind);
+    uword pc_offset = pc_ - code().EntryPoint();
     while (iter.MoveNext()) {
-      if (iter.Pc() == pc_) {
+      if (iter.PcOffset() == pc_offset) {
         try_index_ = iter.TryIndex();
         token_pos_ = iter.TokenPos();
         break;
       }
     }
   }
   return token_pos_;
 }
 
 
@@ skipping 1061 matching lines @@
   // For all token positions on the same line, select the one
   // with the lowest compiled code address. E.g., in a line with
   // the nested function calls f(g(x)), the call g() will have a lower
   // compiled code address but is not the lowest token position in the
   // line.
   if (best_fit_pos != INT_MAX) {
     const Script& script = Script::Handle(func.script());
     const TokenStream& tokens = TokenStream::Handle(script.tokens());
     const intptr_t begin_pos = best_fit_pos;
     const intptr_t end_of_line_pos = LastTokenOnLine(tokens, begin_pos);
-    uword lowest_pc = kUwordMax;
+    uword lowest_pc_offset = kUwordMax;
     PcDescriptors::Iterator iter(desc, kSafepointKind);
     while (iter.MoveNext()) {
       const intptr_t pos = iter.TokenPos();
       if ((pos != Scanner::kNoSourcePos) &&
           (begin_pos <= pos) && (pos <= end_of_line_pos) &&
-          (iter.Pc() < lowest_pc)) {
-        lowest_pc = iter.Pc();
+          (iter.PcOffset() < lowest_pc_offset)) {
+        lowest_pc_offset = iter.PcOffset();
         best_fit_pos = pos;
       }
     }
     return best_fit_pos;
   }
 
   // We didn't find a safe point in the given token range. Try and find
   // a safe point in the remaining source code of the function.
   if (last_token_pos < func.end_token_pos()) {
     return ResolveBreakpointPos(func, last_token_pos, func.end_token_pos());
   }
   return -1;
 }
 
 
 void Debugger::MakeCodeBreakpointAt(const Function& func,
                                     SourceBreakpoint* bpt) {
   ASSERT(bpt->token_pos_ != Scanner::kNoSourcePos);
   ASSERT((bpt != NULL) && bpt->IsResolved());
   ASSERT(!func.HasOptimizedCode());
   Code& code = Code::Handle(func.unoptimized_code());
   ASSERT(!code.IsNull());
   PcDescriptors& desc = PcDescriptors::Handle(code.pc_descriptors());
-  uword lowest_pc = kUwordMax;
+  uword lowest_pc_offset = kUwordMax;
   RawPcDescriptors::Kind lowest_kind = RawPcDescriptors::kAnyKind;
   // Find the safe point with the lowest compiled code address
   // that maps to the token position of the source breakpoint.
   PcDescriptors::Iterator iter(desc, kSafepointKind);
   while (iter.MoveNext()) {
     if (iter.TokenPos() == bpt->token_pos_) {
-      if (iter.Pc() < lowest_pc) {
-        lowest_pc = iter.Pc();
+      if (iter.PcOffset() < lowest_pc_offset) {
+        lowest_pc_offset = iter.PcOffset();
         lowest_kind = iter.Kind();
       }
     }
   }
-  if (lowest_pc == kUwordMax) {
+  if (lowest_pc_offset == kUwordMax) {
     return;
   }
+  uword lowest_pc = code.EntryPoint() + lowest_pc_offset;
   CodeBreakpoint* code_bpt = GetCodeBreakpoint(lowest_pc);
   if (code_bpt == NULL) {
     // No code breakpoint for this code exists; create one.
     code_bpt = new CodeBreakpoint(code, bpt->token_pos_,
                                   lowest_pc, lowest_kind);
     RegisterCodeBreakpoint(code_bpt);
   }
   code_bpt->set_src_bpt(bpt);
   if (bpt->IsEnabled()) {
     code_bpt->Enable();
@@ skipping 1092 matching lines @@
 }
 
 
 void Debugger::RegisterCodeBreakpoint(CodeBreakpoint* bpt) {
   ASSERT(bpt->next() == NULL);
   bpt->set_next(code_breakpoints_);
   code_breakpoints_ = bpt;
 }
 
 }  // namespace dart