One more iteration of PcDescriptor iterator improvement: do not copy record but access individual …

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 345 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);
     while (iter.HasNext()) {
-      RawPcDescriptors::PcDescriptorRec rec;
-      iter.NextRec(&rec);
-      if (rec.pc() == pc_) {
-        try_index_ = rec.try_index();
-        token_pos_ = rec.token_pos();
+      const uword pc = iter.NextPc();
+      if (pc == pc_) {
+        try_index_ = iter.current_try_index();
+        token_pos_ = iter.current_token_pos();
         break;
       }
     }
   }
   return token_pos_;
 }
 
 
 intptr_t ActivationFrame::TryIndex() {
   if (!token_pos_initialized_) {
@@ skipping 543 matching lines @@
   }
 }
 
 
 const uint8_t kSafepointKind =
     RawPcDescriptors::kIcCall |  RawPcDescriptors::kOptStaticCall |
     RawPcDescriptors::kUnoptStaticCall | RawPcDescriptors::kClosureCall |
     RawPcDescriptors::kRuntimeCall;
 
 
-static bool HasTokenPos(const RawPcDescriptors::PcDescriptorRec& rec) {
-  return rec.token_pos() != Scanner::kNoSourcePos;
-}
-
-
 CodeBreakpoint::CodeBreakpoint(const Code& code,
-                               const RawPcDescriptors::PcDescriptorRec& rec)
+                               intptr_t token_pos,
+                               uword pc,
+                               RawPcDescriptors::Kind kind)
     : code_(code.raw()),
-      token_pos_(rec.token_pos()),
-      pc_(rec.pc()),
+      token_pos_(token_pos),
+      pc_(pc),
       line_number_(-1),
       is_enabled_(false),
       src_bpt_(NULL),
       next_(NULL),
-      breakpoint_kind_(rec.kind()),
+      breakpoint_kind_(kind),
       saved_value_(0) {
   ASSERT(!code.IsNull());
   ASSERT(token_pos_ > 0);
   ASSERT(pc_ != 0);
   ASSERT((breakpoint_kind_ & kSafepointKind) != 0);
 }
 
 
 CodeBreakpoint::~CodeBreakpoint() {
   // Make sure we don't leave patched code behind.
@@ skipping 239 matching lines @@
   }
   // Hang on to the code object before deoptimizing, in case deoptimization
   // might cause the GC to run.
   Code& code = Code::Handle(isolate, target_function.unoptimized_code());
   ASSERT(!code.IsNull());
   DeoptimizeWorld();
   ASSERT(!target_function.HasOptimizedCode());
   PcDescriptors& desc = PcDescriptors::Handle(isolate, code.pc_descriptors());
   PcDescriptors::Iterator iter(desc, kSafepointKind);
   while (iter.HasNext()) {
-    RawPcDescriptors::PcDescriptorRec rec;
-    iter.NextRec(&rec);
-    if (HasTokenPos(rec)) {
-      CodeBreakpoint* bpt = GetCodeBreakpoint(rec.pc());
+    const intptr_t token_pos = iter.NextTokenPos();
+    if (token_pos != Scanner::kNoSourcePos) {
+      CodeBreakpoint* bpt = GetCodeBreakpoint(iter.current_pc());
       if (bpt != NULL) {
         // There is already a breakpoint for this address. Make sure
         // it is enabled.
         bpt->Enable();
         continue;
       }
-      bpt = new CodeBreakpoint(code, rec);
+      bpt = new CodeBreakpoint(code, iter.current_token_pos(),
+                               iter.current_pc(), iter.current_kind());
       RegisterCodeBreakpoint(bpt);
       bpt->Enable();
     }
   }
 }
 
 
 void Debugger::SignalBpResolved(SourceBreakpoint* bpt) {
   if (HasEventHandler()) {
     DebuggerEvent event(isolate_, DebuggerEvent::kBreakpointResolved);
@@ skipping 317 matching lines @@
   }
 
   Code& code = Code::Handle(func.unoptimized_code());
   ASSERT(!code.IsNull());
   PcDescriptors& desc = PcDescriptors::Handle(code.pc_descriptors());
   intptr_t best_fit_pos = INT_MAX;
   uword lowest_pc = kUwordMax;
   intptr_t lowest_pc_token_pos = INT_MAX;
   PcDescriptors::Iterator iter(desc, kSafepointKind);
   while (iter.HasNext()) {
-    RawPcDescriptors::PcDescriptorRec rec;
-    iter.NextRec(&rec);
-    intptr_t desc_token_pos = rec.token_pos();
+    const intptr_t desc_token_pos = iter.NextTokenPos();
     ASSERT(desc_token_pos >= 0);
-    if (HasTokenPos(rec)) {
+    if (desc_token_pos != Scanner::kNoSourcePos) {
       if ((desc_token_pos < requested_token_pos) ||
           (desc_token_pos > last_token_pos)) {
         // This descriptor is outside the desired token range.
         continue;
       }
       if (desc_token_pos < best_fit_pos) {
         // So far, this descriptor has the lowest token position after
         // the first acceptable token position.
         best_fit_pos = desc_token_pos;
       }
-      if (rec.pc() < lowest_pc) {
+      if (iter.current_pc() < lowest_pc) {
         // This descriptor so far has the lowest code address.
-        lowest_pc = rec.pc();
+        lowest_pc = iter.current_pc();
         lowest_pc_token_pos = desc_token_pos;
       }
     }
   }
   if (lowest_pc_token_pos != INT_MAX) {
     // We found the pc descriptor that has the lowest execution address.
     // This is the first possible breakpoint after the requested token
     // position. We use this instead of the nearest PC descriptor
     // measured in token index distance.
     return lowest_pc_token_pos;
   }
   if (best_fit_pos != INT_MAX) {
     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;
+  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);
-  RawPcDescriptors::PcDescriptorRec lowest_rec;
   while (iter.HasNext()) {
-    RawPcDescriptors::PcDescriptorRec rec;
-    iter.NextRec(&rec);
-    intptr_t desc_token_pos = rec.token_pos();
-    if ((desc_token_pos == bpt->token_pos_) && HasTokenPos(rec)) {
-      if (rec.pc() < lowest_pc) {
-        lowest_pc = rec.pc();
-        lowest_rec = rec;
+    intptr_t desc_token_pos = iter.NextTokenPos();
+    if (desc_token_pos == bpt->token_pos_) {
+      if (iter.current_pc() < lowest_pc) {
+        lowest_pc = iter.current_pc();
+        lowest_kind = iter.current_kind();
       }
     }
   }
   if (lowest_pc == kUwordMax) {
     return;
   }
-  CodeBreakpoint* code_bpt = GetCodeBreakpoint(lowest_rec.pc());
+  CodeBreakpoint* code_bpt = GetCodeBreakpoint(lowest_pc);
   if (code_bpt == NULL) {
     // No code breakpoint for this code exists; create one.
-    code_bpt = new CodeBreakpoint(code, lowest_rec);
+    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();
   }
 }
 
 
 void Debugger::FindCompiledFunctions(const Script& script,
@@ skipping 941 matching lines @@
 }
 
 
 void Debugger::RegisterCodeBreakpoint(CodeBreakpoint* bpt) {
   ASSERT(bpt->next() == NULL);
   bpt->set_next(code_breakpoints_);
   code_breakpoints_ = bpt;
 }
 
 }  // namespace dart