Port and integrate the irregexp engine from V8

runtime/vm/intrinsifier_x64.cc

Index: runtime/vm/intrinsifier_x64.cc
diff --git a/runtime/vm/intrinsifier_x64.cc b/runtime/vm/intrinsifier_x64.cc
index e816a8ba93d3ec6d88c64baef4fdb1b469bc5877..892681d18b241b103f161b2d3e25f060a724d720 100644
--- a/runtime/vm/intrinsifier_x64.cc
+++ b/runtime/vm/intrinsifier_x64.cc
@@ -8,9 +8,11 @@
 #include "vm/intrinsifier.h"
 
 #include "vm/assembler.h"
+#include "vm/dart_entry.h"
 #include "vm/flow_graph_compiler.h"
 #include "vm/instructions.h"
 #include "vm/object_store.h"
+#include "vm/regexp_assembler.h"
 #include "vm/symbols.h"
 
 namespace dart {
@@ -1535,6 +1537,44 @@ void Intrinsifier::TwoByteString_equality(Assembler* assembler) {
 }
 
 
+#ifndef USE_JSCRE
+void Intrinsifier::JSRegExp_ExecuteMatch(Assembler* assembler) {
+  static const intptr_t kRegExpParamOffset = + 3 * kWordSize;
+  static const intptr_t kStringParamOffset = + 2 * kWordSize;
+  // const Smi& start_index is located at   (+ 1 * kWordSize).
+
+  // Register assignments are as follows:
+  // RAX: The appropriate specialized matcher function.
+  // RBX: The regexp object.
+  // RDI: Temp, Pointer to the function's code which we then tail-call.
+
+  __ movq(RBX, Address(RSP, kRegExpParamOffset));
+  __ movq(RDI, Address(RSP, kStringParamOffset));
+
+  // Load the specialized function pointer into RAX. Leverage the fact the
+  // string CIDs as well as stored function pointers are in sequence.
+
+  __ LoadClassId(RDI, RDI);
+  __ SubImmediate(RDI, Immediate(kOneByteStringCid), PP);
+  __ movq(RAX, FieldAddress(RBX, RDI, TIMES_8,
+                            JSRegExp::function_offset(kOneByteStringCid)));
+
+  // Registers have been set up for the lazy compile stub at this point.
+  // It expects the function in RAX, the argument descriptor in R10, and
+  // IC-Data in RCX. Explicitly null out IC-Data to ensure its validity.
+
+  static const intptr_t arg_count = RegExpMacroAssembler::kParamCount;
+  __ LoadObject(R10, Array::Handle(ArgumentsDescriptor::New(arg_count)), PP);
+  __ xorq(RCX, RCX);
+
+  // Tail-call the function.
+  __ movq(RDI, FieldAddress(RAX, Function::instructions_offset()));
+  __ addq(RDI, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
+  __ jmp(RDI);
+}
+#endif
+
+
 // On stack: user tag (+1), return-address (+0).
 void Intrinsifier::UserTag_makeCurrent(Assembler* assembler) {
   // RBX: Isolate.