1 // Copyright 2010 the V8 project authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef V8_DIAGNOSTICS_GDB_JIT_H_ 6 #define V8_DIAGNOSTICS_GDB_JIT_H_ 7 8 #include "src/base/address-region.h" 9 10 // 11 // GDB has two ways of interacting with JIT code. With the "JIT compilation 12 // interface", V8 can tell GDB when it emits JIT code. Unfortunately to do so, 13 // it has to create platform-native object files, possibly with platform-native 14 // debugging information. Currently only ELF and Mach-O are supported, which 15 // limits this interface to Linux and Mac OS. This JIT compilation interface 16 // was introduced in GDB 7.0. V8 support can be enabled with the --gdbjit flag. 17 // 18 // The other way that GDB can know about V8 code is via the "custom JIT reader" 19 // interface, in which a GDB extension parses V8's private data to determine the 20 // function, file, and line of a JIT frame, and how to unwind those frames. 21 // This interface was introduced in GDB 7.6. This interface still relies on V8 22 // to register its code via the JIT compilation interface, but doesn't require 23 // that V8 create ELF images. Support will be added for this interface in the 24 // future. 25 // 26 27 namespace v8 { 28 29 struct JitCodeEvent; 30 31 namespace internal { 32 namespace GDBJITInterface { 33 #ifdef ENABLE_GDB_JIT_INTERFACE 34 35 // JitCodeEventHandler that creates ELF/Mach-O objects and registers them with 36 // GDB. 37 void EventHandler(const v8::JitCodeEvent* event); 38 39 // Expose some functions for unittests. These only exercise the logic to add 40 // AddressRegion to CodeMap, and checking for overlap. It does not touch the 41 // actual JITCodeEntry at all. 42 V8_EXPORT_PRIVATE void AddRegionForTesting(const base::AddressRegion region); 43 V8_EXPORT_PRIVATE void ClearCodeMapForTesting(); 44 V8_EXPORT_PRIVATE size_t 45 NumOverlapEntriesForTesting(const base::AddressRegion region); 46 47 #endif 48 } // namespace GDBJITInterface 49 } // namespace internal 50 } // namespace v8 51 52 #endif // V8_DIAGNOSTICS_GDB_JIT_H_ 53