Implement code patcher for x64

src/ia32/assembler-ia32.cc

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // 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.
 //
@@ skipping 139 matching lines @@
 const int RelocInfo::kApplyMask =
   RelocInfo::kCodeTargetMask | 1 << RelocInfo::RUNTIME_ENTRY |
     1 << RelocInfo::JS_RETURN | 1 << RelocInfo::INTERNAL_REFERENCE;
 
 
 void RelocInfo::PatchCode(byte* instructions, int instruction_count) {
   // Patch the code at the current address with the supplied instructions.
   for (int i = 0; i < instruction_count; i++) {
     *(pc_ + i) = *(instructions + i);
   }
+
+  // Indicate that code has changed.
+  CPU::FlushICache(pc_, instruction_count);
 }
 
 
 // Patch the code at the current PC with a call to the target address.
 // Additional guard int3 instructions can be added if required.
 void RelocInfo::PatchCodeWithCall(Address target, int guard_bytes) {
   // Call instruction takes up 5 bytes and int3 takes up one byte.
-  int code_size = 5 + guard_bytes;
+  static const int kCallCodeSize = 5;
+  int code_size = kCallCodeSize + guard_bytes;
+
+  // Create a code patcher.
+  CodePatcher patcher(pc_, code_size);
+
+  // Add a label for checking the size of the code used for returning.
+#ifdef DEBUG
+  Label check_codesize;
+  patcher.masm()->bind(&check_codesize);
+#endif
 
   // Patch the code.
-  CodePatcher patcher(pc_, code_size);
   patcher.masm()->call(target, RelocInfo::NONE);
 
+  // Check that the size of the code generated is as expected.
+  ASSERT_EQ(kCallCodeSize, patcher.masm()->SizeOfCodeGeneratedSince(&check_codesize));
+
   // Add the requested number of int3 instructions after the call.
   for (int i = 0; i < guard_bytes; i++) {
     patcher.masm()->int3();
   }
 }
 
 
 // -----------------------------------------------------------------------------
 // Implementation of Operand
 
@@ skipping 2046 matching lines @@
   push_insn[1] = 13;    // Skip over coverage insns.
   if (coverage_log != NULL) {
     fprintf(coverage_log, "%s\n", file_line);
     fflush(coverage_log);
   }
 }
 
 #endif
 
 } }  // namespace v8::internal