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

runtime/vm/raw_object.h

 // 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.
 
 #ifndef VM_RAW_OBJECT_H_
 #define VM_RAW_OBJECT_H_
 
 #include "platform/assert.h"
 #include "vm/atomic.h"
 #include "vm/globals.h"
@@ skipping 1003 matching lines @@
     kUnoptStaticCall = kOptStaticCall << 1,  // Call to a known target via stub.
     kClosureCall     = kUnoptStaticCall << 1,  // Closure call.
     kRuntimeCall     = kClosureCall << 1,  // Runtime call.
     kOsrEntry        = kRuntimeCall << 1,  // OSR entry point in unopt. code.
     kOther           = kOsrEntry << 1,
     kAnyKind         = 0xFF
   };
 
   // Compressed version assumes try_index is always -1 and does not store it.
   struct PcDescriptorRec {
-    uword pc() const { return pc_; }
-    void set_pc(uword value) { pc_ = value; }
+    uword pc_offset() const { return pc_offset_; }
+    void set_pc_offset(uword value) {
+      ASSERT((sizeof(value) == 4) || Utils::IsUint(32, value));
+      pc_offset_ = value;
+    }
 
     Kind kind() const {
       return static_cast<Kind>(deopt_id_and_kind_ & kAnyKind);
     }
     void set_kind(Kind kind) {
       deopt_id_and_kind_ = (deopt_id_and_kind_ & 0xFFFFFF00) | kind;
     }
 
     int16_t try_index() const { return is_compressed() ? -1 : try_index_; }
     void set_try_index(int16_t value) {
@@ skipping 14 matching lines @@
     void set_deopt_id(int32_t value) {
       ASSERT(Utils::IsInt(24, value));
       deopt_id_and_kind_ = (deopt_id_and_kind_ & 0xFF) | (value << 8);
     }
 
    private:
     bool is_compressed() const {
       return (token_pos_ & 0x1) == 1;
     }
 
-    uword pc_;
+    uint32_t pc_offset_;
     int32_t deopt_id_and_kind_;  // Bits 31..8 -> deopt_id, bits 7..0 kind.
     int32_t token_pos_;  // Bits 31..1 -> token_pos, bit 1 -> compressed flag;
     int16_t try_index_;
   };
 
   // This structure is only used to compute what the size of PcDescriptorRec
   // should be when the try_index_ field is omitted.
   struct CompressedPcDescriptorRec {
-    uword pc_;
+    uint32_t pc_offset_;
     int32_t deopt_id_and_kind_;
     int32_t token_pos_;
   };
 
   static intptr_t RecordSize(bool has_try_index);
 
  private:
   RAW_HEAP_OBJECT_IMPLEMENTATION(PcDescriptors);
 
   static const intptr_t kFullRecSize;
@@ skipping 1073 matching lines @@
   COMPILE_ASSERT(kExternalTypedDataInt8ArrayCid ==
                  kTypedDataInt8ArrayViewCid + 15);
   COMPILE_ASSERT(kByteBufferCid == kExternalTypedDataInt8ArrayCid + 14);
   COMPILE_ASSERT(kNullCid == kByteBufferCid + 1);
   return (kNullCid - kTypedDataInt8ArrayCid);
 }
 
 }  // namespace dart
 
 #endif  // VM_RAW_OBJECT_H_