Port and integrate the irregexp engine from V8

runtime/vm/intrinsifier_mips.cc

Index: runtime/vm/intrinsifier_mips.cc
diff --git a/runtime/vm/intrinsifier_mips.cc b/runtime/vm/intrinsifier_mips.cc
index 736621b24d64185d1dac70232c9fe9f56c8e9b8b..835cb04bbfd780e15fd2d8b2b62b8dac068cdea5 100644
--- a/runtime/vm/intrinsifier_mips.cc
+++ b/runtime/vm/intrinsifier_mips.cc
@@ -1640,6 +1640,92 @@ void Intrinsifier::TwoByteString_equality(Assembler* assembler) {
   StringEquality(assembler, kTwoByteStringCid);
 }
 
+
+static void GenerateRegexpSpecializationFor(
+    Assembler* assembler,
+    intptr_t cid,
+    Label* entry,
+    Label* exit) {
+  ASSERT(cid == kOneByteStringCid || cid == kExternalOneByteStringCid ||
+         cid == kTwoByteStringCid || cid == kExternalTwoByteStringCid);
+
+  __ Bind(entry);
+
+  // The passed string is of class cid.
+
+  __ lw(T0, FieldAddress(T1, JSRegExp::function_offset(cid)));
+
+  // Set the subject if it is currently unset.
+
+  __ LoadObject(T2, Object::null_object());
+  __ lw(T4, FieldAddress(T1, JSRegExp::subject_offset(cid)));
+  __ bnel(T2, T4, exit);
+
+  __ StoreIntoObject(T1,
+                     FieldAddress(T1, JSRegExp::subject_offset(cid)),
+                     T3,
+                     false);
+
+  __ b(exit);
+}
+
+
+void Intrinsifier::JSRegExp_ExecuteMatch(Assembler* assembler) {
+  Label is_one_byte_string;
+  Label is_two_byte_string;
+  Label is_external_one_byte_string;
+  Label is_external_two_byte_string;
+  Label fallthrough;
+
+  static const intptr_t kRegExpParamOffset = + 2 * kWordSize;
+  static const intptr_t kStringParamOffset = + 1 * kWordSize;
+  // const Smi& start_index is located at   (+ 0 * kWordSize).
+
+  // Register assignments are as follows:
+  // T0: The appropriate specialized matcher function.
+  // T1: The regexp object.
+  // T2: Temp.
+  // T4: Temp.
+  // T3: Temp, Pointer to the function's code which we then tail-call.
+
+  __ lw(T1, Address(SP, kRegExpParamOffset));
+  __ lw(T3, Address(SP, kStringParamOffset));
+
+  // Check which string class we have been passed.
+
+  __ LoadClassId(T2, T3);
+
+  __ BranchEqual(T2, kOneByteStringCid, &is_one_byte_string);
+  __ BranchEqual(T2, kTwoByteStringCid, &is_two_byte_string);
+  __ BranchEqual(T2, kExternalOneByteStringCid, &is_external_one_byte_string);
+  __ BranchEqual(T2, kExternalTwoByteStringCid, &is_external_two_byte_string);
+
+  __ Stop("Unexpected class id");
+
+  GenerateRegexpSpecializationFor(assembler, kExternalTwoByteStringCid,
+                                  &is_external_two_byte_string, &fallthrough);
+  GenerateRegexpSpecializationFor(assembler, kExternalOneByteStringCid,
+                                  &is_external_one_byte_string, &fallthrough);
+  GenerateRegexpSpecializationFor(assembler, kTwoByteStringCid,
+                                  &is_two_byte_string, &fallthrough);
+  GenerateRegexpSpecializationFor(assembler, kOneByteStringCid,
+                                  &is_one_byte_string, &fallthrough);
+
+  // T0 contains the appropriate specialized function.
+
+  __ Bind(&fallthrough);
+
+  // Registers have been set up for the lazy compile stub at this point.
+  // It expects the function in T0, the argument descriptor in S4, and
+  // IC-Data in S5. Irregexp generated functions do not use either the
+  // arguments descriptor or IC-Data, and hence these are not set here.
+
+  // Tail-call the function.
+  __ lw(T3, FieldAddress(T0, Function::instructions_offset()));
+  __ AddImmediate(T3, Instructions::HeaderSize() - kHeapObjectTag);
+  __ jr(T3);
+}
+
 // On stack: user tag (+0).
 void Intrinsifier::UserTag_makeCurrent(Assembler* assembler) {
   // T1: Isolate.