Add fast Smi op version of switchable instance calls.

runtime/vm/stub_code_mips.cc

Index: runtime/vm/stub_code_mips.cc
diff --git a/runtime/vm/stub_code_mips.cc b/runtime/vm/stub_code_mips.cc
index 58af41870b02afefe49bd1debde0f3f5e68ae828..abd4ba2d78f778cbac962db5c93d646978001384 100644
--- a/runtime/vm/stub_code_mips.cc
+++ b/runtime/vm/stub_code_mips.cc
@@ -2211,6 +2211,13 @@ void StubCode::GenerateOptimizedIdenticalWithNumberCheckStub(
 }
 
 
+// Called from megamorphic calls.
+//  T0: receiver
+//  S5: MegamorphicCache (preserved)
+// Result:
+//  T1: target entry point
+//  CODE_REG: target Code
+//  S4: arguments descriptor
 void StubCode::EmitMegamorphicLookup(Assembler* assembler) {
   __ LoadTaggedClassIdMayBeSmi(T0, T0);
   // T0: class ID of the receiver (smi).
@@ -2253,13 +2260,6 @@ void StubCode::EmitMegamorphicLookup(Assembler* assembler) {
 }
 
 
-// Called from megamorphic calls.
-//  T0: receiver
-//  S5: MegamorphicCache (preserved)
-// Result:
-//  T1: target entry point
-//  CODE_REG: target Code
-//  S4: arguments descriptor
 void StubCode::GenerateMegamorphicLookupStub(Assembler* assembler) {
   EmitMegamorphicLookup(assembler);
   __ Ret();
@@ -2273,7 +2273,50 @@ void StubCode::GenerateMegamorphicLookupStub(Assembler* assembler) {
 //  T1: target entry point
 //  CODE_REG: target Code object
 //  S4: arguments descriptor
-void StubCode::GenerateICLookupStub(Assembler* assembler) {
+static void EmitICLookup(Assembler* assembler,
+                         intptr_t args_checked,
+                         Token::Kind kind) {
+  if (kind != Token::kILLEGAL) {
+    __ Comment("Fast Smi op");
+    Label not_smi_or_overflow;
+
+    // T0: Receiver.
+    __ lw(T1, Address(SP, 0 * kWordSize));
+    // T1: Argument.
+    __ or_(CMPRES1, T0, T1);
+    __ andi(CMPRES1, CMPRES1, Immediate(kSmiTagMask));
+    __ bne(CMPRES1, ZR, &not_smi_or_overflow);
+
+    switch (kind) {
+      case Token::kADD: {
+        __ AdduDetectOverflow(V0, T1, T0, CMPRES1);  // Add.
+        __ bltz(CMPRES1, &not_smi_or_overflow);  // Fall through on overflow.
+        break;
+      }
+      case Token::kSUB: {
+        __ SubuDetectOverflow(V0, T1, T0, CMPRES1);  // Subtract.
+        __ bltz(CMPRES1, &not_smi_or_overflow);  // Fall through on overflow.
+        break;
+      }
+      case Token::kEQ: {
+        Label true_label, done;
+        __ beq(T1, T0, &true_label);
+        __ LoadObject(V0, Bool::False());
+        __ b(&done);
+        __ Bind(&true_label);
+        __ LoadObject(V0, Bool::True());
+        __ Bind(&done);
+        break;
+      }
+      default: UNIMPLEMENTED();
+    }
+    // Return past the call to lookup result and delay slot.
+    __ addiu(RA, RA, Immediate(2 * Instr::kInstrSize));
+    __ Ret();
+
+    __ Bind(&not_smi_or_overflow);
+  }
+
   Label loop, found, miss;
   __ lw(T6, FieldAddress(S5, ICData::ic_data_offset()));
   __ lw(S4, FieldAddress(S5, ICData::arguments_descriptor_offset()));
@@ -2288,12 +2331,14 @@ void StubCode::GenerateICLookupStub(Assembler* assembler) {
   ASSERT(Smi::RawValue(kIllegalCid) == 0);
   __ beq(T2, ZR, &miss);
 
-  const intptr_t entry_length = ICData::TestEntryLengthFor(1) * kWordSize;
+  const intptr_t entry_length =
+      ICData::TestEntryLengthFor(args_checked) * kWordSize;
   __ AddImmediate(T6, entry_length);  // Next entry.
   __ b(&loop);
 
   __ Bind(&found);
-  const intptr_t target_offset = ICData::TargetIndexFor(1) * kWordSize;
+  const intptr_t target_offset =
+      ICData::TargetIndexFor(args_checked) * kWordSize;
   __ lw(T0, Address(T6, target_offset));
   __ lw(T1, FieldAddress(T0, Function::entry_point_offset()));
   __ lw(CODE_REG, FieldAddress(T0, Function::code_offset()));
@@ -2306,6 +2351,26 @@ void StubCode::GenerateICLookupStub(Assembler* assembler) {
   __ Ret();
 }
 
+
+void StubCode::GenerateICLookupStub(Assembler* assembler) {
+  EmitICLookup(assembler, 1, Token::kILLEGAL);
+}
+
+
+void StubCode::GenerateICSmiAddLookupStub(Assembler* assembler) {
+  EmitICLookup(assembler, 2, Token::kADD);
+}
+
+
+void StubCode::GenerateICSmiSubLookupStub(Assembler* assembler) {
+  EmitICLookup(assembler, 2, Token::kSUB);
+}
+
+
+void StubCode::GenerateICSmiEqualLookupStub(Assembler* assembler) {
+  EmitICLookup(assembler, 2, Token::kEQ);
+}
+
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS